Shooting and stitching to make Giclee prints
124 views
Skip to first unread message
Terry Duell
Nov 4, 2015, 6:56:47 PM11/4/15
to hugi...@googlegroups.com
Hello All,
I have become involved in a project to help an artist friend prepare an
image of a painting to be used to make giclee prints, and I'm looking for
any thoughts on what I should do to get it right and what to avoid.
To date, my friend has had his paintings photographed commercially, with a
medium to large format film camera, the transparency then scanned on a
drum scanner to produce an image that would print at original size at 300
ppi.
I'll be shooting with a Pentax K-3 II (aps-c sensor), and aim to shoot a
2x2 pattern with about 30% overlap vertically and about 50% overlap
horizontally...that's roughly how it works out from the painting and
sensor proportions.
I'll shoot from a weighted tripod, using pixel shift mode, and at this
stage thinking about using a 150-450 lens at about 300mm.
The intention is to set the painting vertical on a stand, with lighting
each side at about 45 deg.
It is a simple matter to set the camera at the correct height shooting
horizontally, but not quite as simple to ensure we are normal to the
painting in the horizontal plane. I would like to try to minimise any
perspective effects as much as possible. The thinking at the moment is to
move the painting vertically and horizontally on a fixed easel to align
for each shot, rather than move the camera. I think we can better keep the
shots normal to the painting by this method.
That's probably enough to be going on with...any thoughts?
Cheers,
--
Regards,
Terry Duell
I have become involved in a project to help an artist friend prepare an
image of a painting to be used to make giclee prints, and I'm looking for
any thoughts on what I should do to get it right and what to avoid.
To date, my friend has had his paintings photographed commercially, with a
medium to large format film camera, the transparency then scanned on a
drum scanner to produce an image that would print at original size at 300
ppi.
I'll be shooting with a Pentax K-3 II (aps-c sensor), and aim to shoot a
2x2 pattern with about 30% overlap vertically and about 50% overlap
horizontally...that's roughly how it works out from the painting and
sensor proportions.
I'll shoot from a weighted tripod, using pixel shift mode, and at this
stage thinking about using a 150-450 lens at about 300mm.
The intention is to set the painting vertical on a stand, with lighting
each side at about 45 deg.
It is a simple matter to set the camera at the correct height shooting
horizontally, but not quite as simple to ensure we are normal to the
painting in the horizontal plane. I would like to try to minimise any
perspective effects as much as possible. The thinking at the moment is to
move the painting vertically and horizontally on a fixed easel to align
for each shot, rather than move the camera. I think we can better keep the
shots normal to the painting by this method.
That's probably enough to be going on with...any thoughts?
Cheers,
--
Regards,
Terry Duell
David W. Jones
Nov 5, 2015, 12:40:15 AM11/5/15
to hugi...@googlegroups.com
Hmm, I'd think that moving the camera on a tripod would be easier than
moving the painting, when it comes to keeping the camera the same
distance from the painting.
Once you position the camera, you might drop a plumb line from bottom
center of tripod, let it hang straight, mark the distance of that point
from the painting, then mark that point. Then measure and mark another
other point the same distance from the painting but out from the other
half of the painting. Then draw a line between the two points and you
have a line to center the tripod on when you move it left/right.
You can minimize the number of tripod moves by shooting top left, bottom
left, bottom right, top right. Then you only have to raise or lower the
camera on the tripod. But you knew that already.
Don't forget vignetting.
David W. Jones
gnome...@gmail.com
wandering the landscape of god
http://dancingtreefrog.com
moving the painting, when it comes to keeping the camera the same
distance from the painting.
Once you position the camera, you might drop a plumb line from bottom
center of tripod, let it hang straight, mark the distance of that point
from the painting, then mark that point. Then measure and mark another
other point the same distance from the painting but out from the other
half of the painting. Then draw a line between the two points and you
have a line to center the tripod on when you move it left/right.
You can minimize the number of tripod moves by shooting top left, bottom
left, bottom right, top right. Then you only have to raise or lower the
camera on the tripod. But you knew that already.
Don't forget vignetting.
gnome...@gmail.com
wandering the landscape of god
http://dancingtreefrog.com
Terry Duell
Nov 5, 2015, 3:42:02 AM11/5/15
to hugi...@googlegroups.com
Hello David,
On Thu, 05 Nov 2015 16:40:07 +1100, David W. Jones <gnome...@gmail.com>
wrote:
> Hmm, I'd think that moving the camera on a tripod would be easier than
> moving the painting, when it comes to keeping the camera the same
> distance from the painting.
>
I did talk a bit more about my thoughts on how the painting might be moved
in a later post, although I didn't go into detail.
The thought is that the easel is fixed in place, and the painting moved
sideways on a support on the easel, and that support raised and lowered
using the easel adjustment mechanism. I'll need to test this to be sure it
will work, and if not then resort to moving the tripod along the lines you
have suggested.
> You can minimize the number of tripod moves by shooting top left, bottom
> left, bottom right, top right. Then you only have to raise or lower the
> camera on the tripod. But you knew that already.
Yes :-)
>
> Don't forget vignetting.
>
That's a stitching/post processing issue...isn't it?
Thanks for your thoughts.
On Thu, 05 Nov 2015 16:40:07 +1100, David W. Jones <gnome...@gmail.com>
wrote:
> Hmm, I'd think that moving the camera on a tripod would be easier than
> moving the painting, when it comes to keeping the camera the same
> distance from the painting.
>
in a later post, although I didn't go into detail.
The thought is that the easel is fixed in place, and the painting moved
sideways on a support on the easel, and that support raised and lowered
using the easel adjustment mechanism. I'll need to test this to be sure it
will work, and if not then resort to moving the tripod along the lines you
have suggested.
> You can minimize the number of tripod moves by shooting top left, bottom
> left, bottom right, top right. Then you only have to raise or lower the
> camera on the tripod. But you knew that already.
>
> Don't forget vignetting.
>
That's a stitching/post processing issue...isn't it?
Thanks for your thoughts.
Markku Kolkka
Nov 5, 2015, 4:41:58 AM11/5/15
to hugi...@googlegroups.com
5.11.2015, 1:56, Terry Duell kirjoitti:
> I'll shoot from a weighted tripod, using pixel shift mode, and at this
> stage thinking about using a 150-450 lens at about 300mm.
I'd suggest a macro lens for best edge to edge sharpness, for example
> I'll shoot from a weighted tripod, using pixel shift mode, and at this
> stage thinking about using a 150-450 lens at about 300mm.
Pentax 100mm F2.8.
> The intention is to set the painting vertical on a stand, with lighting
> each side at about 45 deg.
> It is a simple matter to set the camera at the correct height shooting
> horizontally, but not quite as simple to ensure we are normal to the
> painting in the horizontal plane.
align the reflection of the lens to the center of the image in the
viewfinder/LCD. See: http://www.dpreview.com/forums/thread/3389571
--
Markku Kolkka
markku...@iki.fi
ved...@gmail.com
Nov 5, 2015, 12:55:53 PM11/5/15
to hugin and other free panoramic software
Terry,
I assume that the original image is a true rectangle and you want to produce an exact reproduction at whatever scale your resolution provides. That is, you want your stitched end-result also to be an exact rectangle: there should be no, as you put it, "perspective effects"
Isn’t the simplest way to achieve that within Hugin not to rely so much on precise camera or image positioning and/or direction but rather on the use of horizontal and vertical control points (and of course a rectangular projection). I’ve found it remarkably successful to place h and v control points on each individual constituent image, using any suitable rectangular bounding frame that might be included in the original image. Failing that one can use the edges of the original image, making sure that enough of the surrounding background is included to guarantee that they show. But you’d want to do that anyway to be sure that all the original image is included. I rely on the translation parameters X and Y; others may prefer to rely on varying d and e per image.
Provided the images are tied together with enough internal control points you don’t even need to have h or v points that connect different images. Rather, you can have the same image in both frames of the control-point window.
I’ve found this approach to work well with, for instance, a museum painting photographed from several positions along its length, but from below the level of the painting to avoid tiresome reflections and pointing upwards at it.
I’m not saying you shouldn’t be as normal to the image as is reasonably achievable for each shot, because that helps avoid focussing and resolution inconsistencies across each image. I just don’t believe it is critical in order to achieve an exact reproduction of the shape of the original.
I have a suspicion, though I’ve not tried any systematic comparisons, that it is better to have enough images to ensure that the edges of the original image don’t end up too close to the edges of the constituent images. But maybe your camera gives an image of sufficient quality throughout for you not to have to worry.
Roger Broadie
I assume that the original image is a true rectangle and you want to produce an exact reproduction at whatever scale your resolution provides. That is, you want your stitched end-result also to be an exact rectangle: there should be no, as you put it, "perspective effects"
Isn’t the simplest way to achieve that within Hugin not to rely so much on precise camera or image positioning and/or direction but rather on the use of horizontal and vertical control points (and of course a rectangular projection). I’ve found it remarkably successful to place h and v control points on each individual constituent image, using any suitable rectangular bounding frame that might be included in the original image. Failing that one can use the edges of the original image, making sure that enough of the surrounding background is included to guarantee that they show. But you’d want to do that anyway to be sure that all the original image is included. I rely on the translation parameters X and Y; others may prefer to rely on varying d and e per image.
Provided the images are tied together with enough internal control points you don’t even need to have h or v points that connect different images. Rather, you can have the same image in both frames of the control-point window.
I’ve found this approach to work well with, for instance, a museum painting photographed from several positions along its length, but from below the level of the painting to avoid tiresome reflections and pointing upwards at it.
I’m not saying you shouldn’t be as normal to the image as is reasonably achievable for each shot, because that helps avoid focussing and resolution inconsistencies across each image. I just don’t believe it is critical in order to achieve an exact reproduction of the shape of the original.
I have a suspicion, though I’ve not tried any systematic comparisons, that it is better to have enough images to ensure that the edges of the original image don’t end up too close to the edges of the constituent images. But maybe your camera gives an image of sufficient quality throughout for you not to have to worry.
Roger Broadie
Terry Duell
Nov 5, 2015, 4:39:44 PM11/5/15
to hugi...@googlegroups.com
Hello Roger,
On Fri, 06 Nov 2015 04:32:37 +1100, <ved...@gmail.com> wrote:
> Terry,
>
> I assume that the original image is a true rectangle and you want to
> produce an exact reproduction at whatever scale your resolution provides.
> That is, you want your stitched end-result also to be an exact rectangle:
> there should be no, as you put it, "perspective effects"
>
> Isn’t the simplest way to achieve that within Hugin not to rely so much
> on
> precise camera or image positioning and/or direction but rather on the
> use of horizontal and vertical control points (and of course a
> rectangular
> projection). I’ve found it remarkably successful to place h and v control
> points on each individual constituent image, using any suitable
> rectangular bounding frame that might be included in the original image.
> Failing that
> one can use the edges of the original image, making sure that enough of
> the surrounding background is included to guarantee that they show. But
> you’d
> want to do that anyway to be sure that all the original image is
> included.
> I rely on the translation parameters X and Y; others may prefer to rely
> on varying d and e per image.
You are quite right, and what you describe is what I plan to do, but given
that the whole business of shooting the painting isn't something that can
easily repeated at a later date I prefer to minimise these effects.
> I have a suspicion, though I’ve not tried any systematic comparisons,
> that it is better to have enough images to ensure that the edges of the
> original image don’t end up too close to the edges of the constituent
> images. But
> maybe your camera gives an image of sufficient quality throughout for you
> not to have to worry.
I really don't know if this will be an issue. My initial thoughts on the
shooting pattern do have edges of my images close to the edge of the
painting. I'll have a look at another pattern to avoid this, and maybe we
can shoot both patterns and compare the results.
Thanks for your thoughts
--
Regards,
Terry Duell
On Fri, 06 Nov 2015 04:32:37 +1100, <ved...@gmail.com> wrote:
> Terry,
>
> I assume that the original image is a true rectangle and you want to
> produce an exact reproduction at whatever scale your resolution provides.
> That is, you want your stitched end-result also to be an exact rectangle:
> there should be no, as you put it, "perspective effects"
>
> Isn’t the simplest way to achieve that within Hugin not to rely so much
> on
> precise camera or image positioning and/or direction but rather on the
> use of horizontal and vertical control points (and of course a
> rectangular
> projection). I’ve found it remarkably successful to place h and v control
> points on each individual constituent image, using any suitable
> rectangular bounding frame that might be included in the original image.
> Failing that
> one can use the edges of the original image, making sure that enough of
> the surrounding background is included to guarantee that they show. But
> you’d
> want to do that anyway to be sure that all the original image is
> included.
> I rely on the translation parameters X and Y; others may prefer to rely
> on varying d and e per image.
that the whole business of shooting the painting isn't something that can
easily repeated at a later date I prefer to minimise these effects.
> I have a suspicion, though I’ve not tried any systematic comparisons,
> that it is better to have enough images to ensure that the edges of the
> original image don’t end up too close to the edges of the constituent
> images. But
> maybe your camera gives an image of sufficient quality throughout for you
> not to have to worry.
shooting pattern do have edges of my images close to the edge of the
painting. I'll have a look at another pattern to avoid this, and maybe we
can shoot both patterns and compare the results.
Thanks for your thoughts
--
Regards,
Terry Duell
Terry Duell
Nov 5, 2015, 4:43:21 PM11/5/15
to hugi...@googlegroups.com
Hello Markku,
On Thu, 05 Nov 2015 20:41:57 +1100, Markku Kolkka <markku...@iki.fi>
wrote:
> 5.11.2015, 1:56, Terry Duell kirjoitti:
>> I'll shoot from a weighted tripod, using pixel shift mode, and at this
>> stage thinking about using a 150-450 lens at about 300mm.
>
> I'd suggest a macro lens for best edge to edge sharpness, for example
> Pentax 100mm F2.8.
>
OK, thanks. I'll see if I can find some lens tests to compare.
>> The intention is to set the painting vertical on a stand, with lighting
>> each side at about 45 deg.
>> It is a simple matter to set the camera at the correct height shooting
>> horizontally, but not quite as simple to ensure we are normal to the
>> painting in the horizontal plane.
>
> The traditional method is to place a mirror in place of the painting and
> align the reflection of the lens to the center of the image in the
> viewfinder/LCD. See: http://www.dpreview.com/forums/thread/3389571
>
That's a good idea.
Thanks for your thoughts.
On Thu, 05 Nov 2015 20:41:57 +1100, Markku Kolkka <markku...@iki.fi>
wrote:
> 5.11.2015, 1:56, Terry Duell kirjoitti:
>> I'll shoot from a weighted tripod, using pixel shift mode, and at this
>> stage thinking about using a 150-450 lens at about 300mm.
>
> I'd suggest a macro lens for best edge to edge sharpness, for example
> Pentax 100mm F2.8.
>
>> The intention is to set the painting vertical on a stand, with lighting
>> each side at about 45 deg.
>> It is a simple matter to set the camera at the correct height shooting
>> horizontally, but not quite as simple to ensure we are normal to the
>> painting in the horizontal plane.
>
> The traditional method is to place a mirror in place of the painting and
> align the reflection of the lens to the center of the image in the
> viewfinder/LCD. See: http://www.dpreview.com/forums/thread/3389571
>
Thanks for your thoughts.
Markku Kolkka
Nov 5, 2015, 6:20:32 PM11/5/15
to hugi...@googlegroups.com
5.11.2015, 23:43, Terry Duell kirjoitti:
> Hello Markku,
http://www.pentaxforums.com/reviews/smc-pentax-d-fa-100mm-f28-macro-wr/introduction.html
All the different autofocusing versions of Pentax 100/F2.8 Macro (F, FA,
D-FA and D-FA WR) have basically the same optical design and should have
similar performance.
--
Markku Kolkka
markku...@iki.fi
> Hello Markku,
>> I'd suggest a macro lens for best edge to edge sharpness, for example
>> Pentax 100mm F2.8.
>>
>
> OK, thanks. I'll see if I can find some lens tests to compare.
http://slrgear.com/reviews/showproduct.php/product/310/cat/45
>> Pentax 100mm F2.8.
>>
>
> OK, thanks. I'll see if I can find some lens tests to compare.
http://www.pentaxforums.com/reviews/smc-pentax-d-fa-100mm-f28-macro-wr/introduction.html
All the different autofocusing versions of Pentax 100/F2.8 Macro (F, FA,
D-FA and D-FA WR) have basically the same optical design and should have
similar performance.
--
Markku Kolkka
markku...@iki.fi
Terry Duell
Nov 5, 2015, 6:52:32 PM11/5/15
to hugi...@googlegroups.com
Hello Markku,
On Fri, 06 Nov 2015 10:20:31 +1100, Markku Kolkka <markku...@iki.fi>
wrote:
...to compare with the performance of my 150-450.
On Fri, 06 Nov 2015 10:20:31 +1100, Markku Kolkka <markku...@iki.fi>
wrote:
Marius Loots
Nov 6, 2015, 1:08:32 AM11/6/15
to hugi...@googlegroups.com
Hallo All,
Don't know if this could assist, but thought I would put it out there.
Some many years ago, I was also attempting to photograph and stitch
a difficult subject. Unfortunately I can't remember the detail, but
what I do remember is that the subject was such that it was difficult
to place control points.
What I ended up doing was to place physical markers on the object,
which could then be used as control points and remove using masks.
This could perhaps be used in your case as well to control for
distortions?
Groetnis
Marius
mailto:marius...@up.ac.za
--
add some chaos to your life and put the world in order
http://www.mapungubwe.co.za/
http://www.chaos.co.za/
skype: marius_loots
Hierdie boodskap en aanhangsels is aan 'n vrywaringsklousule
onderhewig. Volledige besonderhede is by
www.it.up.ac.za/documentation/governance/disclaimer/
beskikbaar.
Don't know if this could assist, but thought I would put it out there.
Some many years ago, I was also attempting to photograph and stitch
a difficult subject. Unfortunately I can't remember the detail, but
what I do remember is that the subject was such that it was difficult
to place control points.
What I ended up doing was to place physical markers on the object,
which could then be used as control points and remove using masks.
This could perhaps be used in your case as well to control for
distortions?
Groetnis
Marius
mailto:marius...@up.ac.za
--
add some chaos to your life and put the world in order
http://www.mapungubwe.co.za/
http://www.chaos.co.za/
skype: marius_loots
Hierdie boodskap en aanhangsels is aan 'n vrywaringsklousule
onderhewig. Volledige besonderhede is by
www.it.up.ac.za/documentation/governance/disclaimer/
beskikbaar.
Terry Duell
Nov 6, 2015, 1:25:41 AM11/6/15
to hugi...@googlegroups.com
Hello Marius,
On Fri, 06 Nov 2015 17:08:18 +1100, Marius Loots <mlo...@medic.up.ac.za>
wrote:
> Hallo All,
>
> Don't know if this could assist, but thought I would put it out there.
> Some many years ago, I was also attempting to photograph and stitch
> a difficult subject. Unfortunately I can't remember the detail, but
> what I do remember is that the subject was such that it was difficult
> to place control points.
>
> What I ended up doing was to place physical markers on the object,
> which could then be used as control points and remove using masks.
> This could perhaps be used in your case as well to control for
> distortions?
>
I think the edges of the painting should provide good references which can
be used to set horizontal and vertical lines which should control any
perspective distortion.
Thanks for your advice, worth keeping in mind.
On Fri, 06 Nov 2015 17:08:18 +1100, Marius Loots <mlo...@medic.up.ac.za>
wrote:
> Hallo All,
>
> Don't know if this could assist, but thought I would put it out there.
> Some many years ago, I was also attempting to photograph and stitch
> a difficult subject. Unfortunately I can't remember the detail, but
> what I do remember is that the subject was such that it was difficult
> to place control points.
>
> What I ended up doing was to place physical markers on the object,
> which could then be used as control points and remove using masks.
> This could perhaps be used in your case as well to control for
> distortions?
>
be used to set horizontal and vertical lines which should control any
perspective distortion.
Thanks for your advice, worth keeping in mind.
Markku Kolkka
Nov 6, 2015, 7:29:01 AM11/6/15
to hugi...@googlegroups.com
6.11.2015, 1:52, Terry Duell kirjoitti:
>
>>> OK, thanks. I'll see if I can find some lens tests to compare.
>
>
>>> OK, thanks. I'll see if I can find some lens tests to compare.
>
> ...to compare with the performance of my 150-450.
Ephotozine has tested both lenses, but on different bodies (K-5 IIs vs.
K-3) so the measurements aren't necessarily directly comparable.
https://www.ephotozine.com/article/pentax-hd-pentax-d-fa-150-450mm-f-4-5-5-6-ed-dc-aw-review-27359#Performance
https://www.ephotozine.com/article/pentax-d-fa-100mm-f-2-8-macro-wr-lens-review-24103#Performance
--
Markku Kolkka
markku...@iki.fi
Bill Brody
Nov 6, 2015, 10:27:33 AM11/6/15
to hugin and other free panoramic software
I suggest a prime lens rather than any kind of zoom. They are much sharper. Many lens are sharpest at f8. Check the literature for your lens.
Assuming a size of six feet for the largest dimension of the canvas, then at 300 ppi you will need your output to be 300 x 12 X 6 or 21,600 pixels along that side. This comes out to 466,560,000 or about 450 megapixels. You do not want to use the entire frame of each source image since the peripheral pixels are always less sharp than the ones closer to the center. Even though I use the free hugin for stitching, I use a commercial product, DXO, for preprocessing my images.
Assuming a size of six feet for the largest dimension of the canvas, then at 300 ppi you will need your output to be 300 x 12 X 6 or 21,600 pixels along that side. This comes out to 466,560,000 or about 450 megapixels. You do not want to use the entire frame of each source image since the peripheral pixels are always less sharp than the ones closer to the center. Even though I use the free hugin for stitching, I use a commercial product, DXO, for preprocessing my images.
One way to ensure that your images are all taken with the lens pointing directly at the portion of the canvas you want is to mark that point with masking tape or using two crossed segments of mason twine. Both artwork and camera should be absolutely level, something you can accomplish ith a carpenter's level. Attach a laser pointer alng one leg of a large 45 degree right triangle. Place the other leg of triangle at the intersection point and swing it back and forth to see if the laser points at the center of the lens. If it does with the triangle oriented along the two perpendicular lines define by the mason twin, then your camera is in exactly the right spot. The laser pointer method is from watching James Barker, a professional photographer, take professional medium format slides. You will have probably do better if you hire him to do the photography for you.
dgjohnston
Nov 6, 2015, 2:15:57 PM11/6/15
to Hugin Pano
I also use DxO. And hugin of course. The nice thing about DxO is that correction modules are available for most cameras and lens combinations. It corrects for distortion, vignetting etc. Then hugin can do its magic without having to also correct all that stuff.
Sent from my Samsung device
--
A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ
---
You received this message because you are subscribed to the Google Groups "hugin and other free panoramic software" group.
To unsubscribe from this group and stop receiving emails from it, send an email to hugin-ptx+...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/hugin-ptx/b1615f67-a327-4b37-a325-db8b2d3e382c%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ
---
You received this message because you are subscribed to the Google Groups "hugin and other free panoramic software" group.
To unsubscribe from this group and stop receiving emails from it, send an email to hugin-ptx+...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/hugin-ptx/b1615f67-a327-4b37-a325-db8b2d3e382c%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
Terry Duell
Nov 6, 2015, 5:14:57 PM11/6/15
to hugi...@googlegroups.com
Hello Bill,
On Sat, 07 Nov 2015 02:27:33 +1100, Bill Brody <awb...@gmail.com> wrote:
> I suggest a prime lens rather than any kind of zoom. They are much
> sharper. Many lens are sharpest at f8. Check the literature for your
> lens.
My choice of the Pentax 150-450 is because it's what I have.
The reports for this lens are good, particularly at about 300 and f8.
We aren't going to get another lens just for this experiment, but that
maybe what is done later if it all works out OK.
> Even though I use the free hugin for stitching, I use a commercial
> product, DXO, for preprocessing my images.
It'll be Hugin...from what I can find DxO is not available for Linux.
Thanks for your advice.
On Sat, 07 Nov 2015 02:27:33 +1100, Bill Brody <awb...@gmail.com> wrote:
> I suggest a prime lens rather than any kind of zoom. They are much
> sharper. Many lens are sharpest at f8. Check the literature for your
> lens.
The reports for this lens are good, particularly at about 300 and f8.
We aren't going to get another lens just for this experiment, but that
maybe what is done later if it all works out OK.
> Even though I use the free hugin for stitching, I use a commercial
> product, DXO, for preprocessing my images.
Thanks for your advice.
Paul Womack
Nov 7, 2015, 8:05:12 AM11/7/15
to hugi...@googlegroups.com
Pardon my dumbness; it's seems (from the thread) you're talking about
shooting a mosaic style set; in this context what is a "2x2 pattern"
--
Regards,
Terry Duell
--
A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ
---You received this message because you are subscribed to the Google Groups "hugin and other free panoramic software" group.
To unsubscribe from this group and stop receiving emails from it, send an email to hugin-ptx+...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/hugin-ptx/op.x7lortbwrs0ygh%40localhost.
Terry Duell
Nov 7, 2015, 5:38:21 PM11/7/15
to hugi...@googlegroups.com
Hello Paul,
On Sun, 08 Nov 2015 00:05:09 +1100, Paul Womack <pwo...@papermule.com>
wrote:
> Pardon my dumbness; it's seems (from the thread) you're talking about
> shooting a mosaic style set; in this context what is a "2x2 pattern"
> (since I suspect the full matrix will be more 8x13 images or whatever).
>
Yes, it will be shot in mosaic mode.
The 2x2 pattern is simply 2 rows, 2 columns, 4 shots in total.
> Second - how big is the physical painting?
The painting is 760x560mm.
On Sun, 08 Nov 2015 00:05:09 +1100, Paul Womack <pwo...@papermule.com>
wrote:
> Pardon my dumbness; it's seems (from the thread) you're talking about
> shooting a mosaic style set; in this context what is a "2x2 pattern"
> (since I suspect the full matrix will be more 8x13 images or whatever).
>
The 2x2 pattern is simply 2 rows, 2 columns, 4 shots in total.
> Second - how big is the physical painting?
panostar
Nov 8, 2015, 8:06:31 AM11/8/15
to hugin and other free panoramic software
Terry, Your camera with a 300mm lens will be quite a long way from the canvas. If you have a spherical panorama head, I would use that and stitch as a conventional panorama rather than use mosaic mode.
John
Paul Womack
Nov 8, 2015, 10:17:36 AM11/8/15
to hugi...@googlegroups.com
That's why I asked about the shooting pattern and physical size.
I concur with using a pano head and "normal" stitching.--
A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ
---
You received this message because you are subscribed to the Google Groups "hugin and other free panoramic software" group.
To unsubscribe from this group and stop receiving emails from it, send an email to hugin-ptx+...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/hugin-ptx/f380e2ad-b667-4081-b925-77ec0c131ef8%40googlegroups.com.
Terry Duell
Nov 8, 2015, 4:21:01 PM11/8/15
to hugi...@googlegroups.com
Hello John,
On Mon, 09 Nov 2015 00:06:31 +1100, panostar <houghto...@gmail.com>
wrote:
> Terry, Your camera with a 300mm lens will be quite a long way from the
> canvas. If you have a spherical panorama head, I would use that and
> stitch as a conventional panorama rather than use mosaic mode.
>
I think the camera will be about 6.5m from the painting, but I don't have
a pano head, hence the current obsession with mosaic mode.
There will be quite a lot of experimental stuff going on at the time, and
one is to shoot a conventional pano, but I have been thinking that mosaic
mode would be my best approach.
Thanks for your thoughts on this.
On Mon, 09 Nov 2015 00:06:31 +1100, panostar <houghto...@gmail.com>
wrote:
> Terry, Your camera with a 300mm lens will be quite a long way from the
> canvas. If you have a spherical panorama head, I would use that and
> stitch as a conventional panorama rather than use mosaic mode.
>
a pano head, hence the current obsession with mosaic mode.
There will be quite a lot of experimental stuff going on at the time, and
one is to shoot a conventional pano, but I have been thinking that mosaic
mode would be my best approach.
Thanks for your thoughts on this.
Paul Womack
Nov 8, 2015, 4:29:44 PM11/8/15
to hugi...@googlegroups.com
Moving the painting would, unless your lighting is perfectly uniform, involve moving the painting w.r.t. the lights, which might make a perfect stitch impossible.
I would (quite strongly) recommend a pano head, home made if need be. Given the lack of major 3d
features on a painting it needn't be perfect.
A home made one is probably only going to work for a fixed focal length though, which might be an issue with a zoom lens.
A home made one is probably only going to work for a fixed focal length though, which might be an issue with a zoom lens.
In any case (speaking from experience) mosaic shooting brings is own quite nasty parallax issues.
I experience much of this when doing my maps-in-an-archive shoot, recently.
I would certainly do test shoots with a cheap poster, or something.
--
A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ
---You received this message because you are subscribed to the Google Groups "hugin and other free panoramic software" group.
To unsubscribe from this group and stop receiving emails from it, send an email to hugin-ptx+...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/hugin-ptx/op.x7sv87sers0ygh%40localhost.
Terry Duell
Nov 8, 2015, 4:46:52 PM11/8/15
to hugi...@googlegroups.com
Hello Paul,
On Mon, 09 Nov 2015 08:29:39 +1100, Paul Womack <pwo...@papermule.com>
wrote:
> Moving the painting would, unless your lighting is perfectly uniform,
> involve moving the painting w.r.t. the lights, which might make a perfect
> stitch impossible.
Yes that is an issue, and we have more or less decided that keeping the
painting in a fixed position is probably the better method.
> I would (quite strongly) recommend a pano head, home made if need be.
> Given the lack of major 3d features on a painting it needn't be perfect.
It would be nice to have one, but won't be tackling the home made solution.
> I would certainly do test shoots with a cheap poster, or something.
This is a test shoot.
Thanks for your advice.
On Mon, 09 Nov 2015 08:29:39 +1100, Paul Womack <pwo...@papermule.com>
wrote:
> Moving the painting would, unless your lighting is perfectly uniform,
> involve moving the painting w.r.t. the lights, which might make a perfect
> stitch impossible.
painting in a fixed position is probably the better method.
> I would (quite strongly) recommend a pano head, home made if need be.
> Given the lack of major 3d features on a painting it needn't be perfect.
> I would certainly do test shoots with a cheap poster, or something.
Thanks for your advice.
dgjohnston
Nov 8, 2015, 5:26:50 PM11/8/15
to Hugin Pano
Terry, at 6.5m and with a relatively flat painting I can't see there being anything to produce parallax errors. Or am I showing my naivety here? Feel free to let me know if I'm out to lunch on this! ;o)
I'd try experimenting with just rotating the camera and doing a normal piano stitch.
Sent from my Samsung device
-------- Original message --------
From: Terry Duell <tdu...@iinet.net.au>
Date: 2015-11-08 3:20 PM (GMT-06:00)
To: hugi...@googlegroups.com
Subject: Re: [hugin-ptx] Shooting and stitching to make Giclee prints
Hello John,
On Mon, 09 Nov 2015 00:06:31 +1100, panostar <houghto...@gmail.com>
wrote:
> Terry, Your camera with a 300mm lens will be quite a long way from the
> canvas. If you have a spherical panorama head, I would use that and
> stitch as a conventional panorama rather than use mosaic mode.
>
I think the camera will be about 6.5m from the painting, but I don't have
a pano head, hence the current obsession with mosaic mode.
There will be quite a lot of experimental stuff going on at the time, and
one is to shoot a conventional pano, but I have been thinking that mosaic
mode would be my best approach.
Thanks for your thoughts on this.
Date: 2015-11-08 3:20 PM (GMT-06:00)
To: hugi...@googlegroups.com
Subject: Re: [hugin-ptx] Shooting and stitching to make Giclee prints
Hello John,
On Mon, 09 Nov 2015 00:06:31 +1100, panostar <houghto...@gmail.com>
wrote:
> Terry, Your camera with a 300mm lens will be quite a long way from the
> canvas. If you have a spherical panorama head, I would use that and
> stitch as a conventional panorama rather than use mosaic mode.
>
I think the camera will be about 6.5m from the painting, but I don't have
a pano head, hence the current obsession with mosaic mode.
There will be quite a lot of experimental stuff going on at the time, and
one is to shoot a conventional pano, but I have been thinking that mosaic
mode would be my best approach.
Thanks for your thoughts on this.
Cheers,
--
Regards,
Terry Duell
--
Regards,
Terry Duell
Terry Duell
Nov 8, 2015, 5:51:18 PM11/8/15
to hugi...@googlegroups.com
Hello dg,
Sorry, I forget if you are a David,
On Mon, 09 Nov 2015 09:26:45 +1100, dgjohnston <dgjoh...@accesscomm.ca>
wrote:
>
> Terry, at 6.5m and with a relatively flat painting I can't see there
> being anything to produce parallax errors. Or am I showing my naivety
> here? Feel free to let me know if I'm out to lunch on this! ;o)
I think you are quite correct, the parallax should be minimal.
No I don't think you are showing any more naivety than myself on this.
The reason I have become a bit obsessed with mosaic mode for this project
is the Giclee (should be an accent on the c...can't see how to easily do
that at the moment ) prints should be an exact, or as near as dammit, copy
of the original, and that means a true rectangle i.e no perspective
distortion which is what I will get with a normal pano.
Now I know that it should be possible to correct that in Hugin, and
normally that works OK but I have had projects where that has proved to be
a bit of a pain...so all the emphasis on mosaic and how to ensure camera
square to subject etc.
> I'd try experimenting with just rotating the camera and doing a normal
> piano stitch.
I can't play piano, so will resort to simple pano :-)
Yes, the dance card now includes mosaic mode pano shots, normal pano
shots, with pixel shift, without pixel shift, automatic white balance,
manual white balance. It's getting bigger than Ben Hur!
Thanks for your help.
Sorry, I forget if you are a David,
On Mon, 09 Nov 2015 09:26:45 +1100, dgjohnston <dgjoh...@accesscomm.ca>
wrote:
>
> Terry, at 6.5m and with a relatively flat painting I can't see there
> being anything to produce parallax errors. Or am I showing my naivety
> here? Feel free to let me know if I'm out to lunch on this! ;o)
No I don't think you are showing any more naivety than myself on this.
The reason I have become a bit obsessed with mosaic mode for this project
is the Giclee (should be an accent on the c...can't see how to easily do
that at the moment ) prints should be an exact, or as near as dammit, copy
of the original, and that means a true rectangle i.e no perspective
distortion which is what I will get with a normal pano.
Now I know that it should be possible to correct that in Hugin, and
normally that works OK but I have had projects where that has proved to be
a bit of a pain...so all the emphasis on mosaic and how to ensure camera
square to subject etc.
> I'd try experimenting with just rotating the camera and doing a normal
> piano stitch.
Yes, the dance card now includes mosaic mode pano shots, normal pano
shots, with pixel shift, without pixel shift, automatic white balance,
manual white balance. It's getting bigger than Ben Hur!
Thanks for your help.
dgjohnston
Nov 8, 2015, 7:02:14 PM11/8/15
to Hugin Pano
I'm a Donald and I don't play the piano either. As they say "Spell check is my new wrost enema!"
Sent from my Samsung device
-------- Original message --------
From: Terry Duell <tdu...@iinet.net.au>
Date: 2015-11-08 4:50 PM (GMT-06:00)
To: hugi...@googlegroups.com
Subject: Re: [hugin-ptx] Shooting and stitching to make Giclee prints
--
A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ
---
You received this message because you are subscribed to the Google Groups "hugin and other free panoramic software" group.
To unsubscribe from this group and stop receiving emails from it, send an email to hugin-ptx+...@googlegroups.com.
A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ
---
You received this message because you are subscribed to the Google Groups "hugin and other free panoramic software" group.
To unsubscribe from this group and stop receiving emails from it, send an email to hugin-ptx+...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/hugin-ptx/op.x7s0e0lgrs0ygh%40localhost.
Terry Duell
Nov 8, 2015, 9:34:57 PM11/8/15
to hugi...@googlegroups.com
Hello Donald,
On Mon, 09 Nov 2015 11:02:07 +1100, dgjohnston <dgjoh...@accesscomm.ca>
wrote:
>
> I'm a Donald and I don't play the piano either. As they say "Spell check
> is my new wrost enema!"
>
Ha ha. The dreaded spill chucker, I should have known.
On Mon, 09 Nov 2015 11:02:07 +1100, dgjohnston <dgjoh...@accesscomm.ca>
wrote:
>
> I'm a Donald and I don't play the piano either. As they say "Spell check
> is my new wrost enema!"
>
Paul Womack
Nov 9, 2015, 4:05:31 AM11/9/15
to hugi...@googlegroups.com
A pano head merely reduces parallax errors (ideally, but never, to zero).
As I have discovered, mosaicing generates very large parallax errors.This may not be ideal, but it may be better than mosaicing.
(and a pano head that is far from perfect, but far better
than a normal 3 way head could be knocked up in a shed!)
BugBear
--
A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ
---You received this message because you are subscribed to the Google Groups "hugin and other free panoramic software" group.
To unsubscribe from this group and stop receiving emails from it, send an email to hugin-ptx+...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/hugin-ptx/op.x7sxgav7rs0ygh%40localhost.
Paul Womack
Nov 9, 2015, 4:08:24 AM11/9/15
to hugi...@googlegroups.com
On 8 November 2015 at 22:50, Terry Duell <tdu...@iinet.net.au> wrote:
Now I know that it should be possible to correct that in Hugin, and normally that works OK but I have had projects where that has proved to be a bit of a pain...so all the emphasis on mosaic and how to ensure camera square to subject etc.
Hmm. I will bet good money that you can measure out of square more accurately in post production than can during shooting.
Further, if you measure the painting, you can also ensure that the final stitch is both rectilinear and of the perfect aspect ratio.
BugBear
panostar
Nov 9, 2015, 7:57:15 AM11/9/15
to hugin and other free panoramic software
On Monday, November 9, 2015 at 9:05:31 AM UTC, bugbear wrote:
(and a pano head that is far from perfect, but far betterthan a normal 3 way head could be knocked up in a shed!)
All that is required in this case is a simple plate or bar adapter to shift the camera back (or possibly forwards) to align the entrance pupil of the lens with the axis of rotation. That would virtually eliminate horizontal parallax. Any minor shift of the entrance pupil in the vertical direction can be can be compensated for by a small adjustment in the height of the centre column. Should cost next to nothing and take no more than an hour or two to make.
My first panorama head was just such a design and consisted of a strip of wood to shift the camera back, and an L-bracket ( an old flash bracket) to hold the camera in portrait orientation, but the latter would not be needed for the painting panorama. The wooden bar fitted into the QR of the pan&tilt head of the cheap Velbon tripod.
Panohead: http://www.johnhpanos.com/panhead.jpg
First panorama shot with it 10 years ago: http://www.johnhpanos.com/spherical/zane5000/zane5000.html
John
Terry Duell
Nov 9, 2015, 5:59:56 PM11/9/15
to hugi...@googlegroups.com
Hello Paul,
On Mon, 09 Nov 2015 20:08:18 +1100, Paul Womack <pwo...@papermule.com>
wrote:
> On 8 November 2015 at 22:50, Terry Duell <tdu...@iinet.net.au> wrote:
>
>> Now I know that it should be possible to correct that in Hugin, and
>> normally that works OK but I have had projects where that has proved to
>> be
>> a bit of a pain...so all the emphasis on mosaic and how to ensure camera
>> square to subject etc.
>>
>
> Hmm. I will bet good money that you can measure out of square more
> accurately in post production than can during shooting.
Probably.
>
> Further, if you measure the painting, you can also ensure that the final
> stitch is both rectilinear and of the perfect aspect ratio.
Yes.
On Mon, 09 Nov 2015 20:08:18 +1100, Paul Womack <pwo...@papermule.com>
wrote:
> On 8 November 2015 at 22:50, Terry Duell <tdu...@iinet.net.au> wrote:
>
>> Now I know that it should be possible to correct that in Hugin, and
>> normally that works OK but I have had projects where that has proved to
>> be
>> a bit of a pain...so all the emphasis on mosaic and how to ensure camera
>> square to subject etc.
>>
>
> Hmm. I will bet good money that you can measure out of square more
> accurately in post production than can during shooting.
>
> Further, if you measure the painting, you can also ensure that the final
> stitch is both rectilinear and of the perfect aspect ratio.
bugbear
Nov 10, 2015, 4:31:07 AM11/10/15
to hugi...@googlegroups.com
panostar wrote:
>
> All that is required in this case is a simple plate or bar adapter to shift the camera back (or possibly forwards) to align the entrance pupil of the lens with the axis of rotation. That would virtually eliminate horizontal parallax. Any minor shift of the entrance pupil in the vertical direction can be can be compensated for by a small adjustment in the height of the centre column. Should cost next to nothing and take no more than an hour or two to make.
>
> My first panorama head was just such a design and consisted of a strip of wood to shift the camera back, and an L-bracket ( an old flash bracket) to hold the camera in portrait orientation, but the latter would not be needed for the painting panorama. The wooden bar fitted into the QR of the pan&tilt head of the cheap Velbon tripod.
>
> Panohead: http://www.johnhpanos.com/panhead.jpg
> First panorama shot with it 10 years ago: http://www.johnhpanos.com/spherical/zane5000/zane5000.html
I love that you bothered to paint it black!
>
> All that is required in this case is a simple plate or bar adapter to shift the camera back (or possibly forwards) to align the entrance pupil of the lens with the axis of rotation. That would virtually eliminate horizontal parallax. Any minor shift of the entrance pupil in the vertical direction can be can be compensated for by a small adjustment in the height of the centre column. Should cost next to nothing and take no more than an hour or two to make.
>
> My first panorama head was just such a design and consisted of a strip of wood to shift the camera back, and an L-bracket ( an old flash bracket) to hold the camera in portrait orientation, but the latter would not be needed for the painting panorama. The wooden bar fitted into the QR of the pan&tilt head of the cheap Velbon tripod.
>
> Panohead: http://www.johnhpanos.com/panhead.jpg
> First panorama shot with it 10 years ago: http://www.johnhpanos.com/spherical/zane5000/zane5000.html
BugBear
Terry Duell
Nov 10, 2015, 4:15:48 PM11/10/15
to hugi...@googlegroups.com
On Tue, 10 Nov 2015 10:03:46 +1100, wrote:
> Hello John,
[snip]
> You're probably right, if you did it.
> For me it would take a day, or so, to sort out where the entrance pupil
> is, then another day, or so, to make the gadget, then another day, or
> so, to test it and...
> Why is that blokes who can knock up an 8 speed auto transmission out of
> jam tins before lunch, always reckon it's easy for everyone else :-)
>
Thinking about this, I feel a bit bad that it might have come across as a
bit nasty, even with the smiley.
I hope it wasn't received that way, it wasn't meant to be anything but an
attempt at humour.
I can tend to write my emails as if I'm in conversation, face to face, and
can be misunderstood.
I know your advice is well meant, and it is appreciated.
> Hello John,
[snip]
> You're probably right, if you did it.
> For me it would take a day, or so, to sort out where the entrance pupil
> is, then another day, or so, to make the gadget, then another day, or
> so, to test it and...
> Why is that blokes who can knock up an 8 speed auto transmission out of
> jam tins before lunch, always reckon it's easy for everyone else :-)
>
Thinking about this, I feel a bit bad that it might have come across as a
bit nasty, even with the smiley.
I hope it wasn't received that way, it wasn't meant to be anything but an
attempt at humour.
I can tend to write my emails as if I'm in conversation, face to face, and
can be misunderstood.
I know your advice is well meant, and it is appreciated.
panostar
Nov 10, 2015, 6:17:27 PM11/10/15
to hugin and other free panoramic software
On Tuesday, November 10, 2015 at 9:15:48 PM UTC, Tduell wrote:
On Tue, 10 Nov 2015 10:03:46 +1100, wrote:
> Hello John,
[snip]
> You're probably right, if you did it.
> For me it would take a day, or so, to sort out where the entrance pupil
> is, then another day, or so, to make the gadget, then another day, or
> so, to test it and...
> Why is that blokes who can knock up an 8 speed auto transmission out of
> jam tins before lunch, always reckon it's easy for everyone else :-)
>
Thinking about this, I feel a bit bad that it might have come across as a
bit nasty, even with the smiley.
I hope it wasn't received that way, it wasn't meant to be anything but an
attempt at humour.
Terry,I haven't seen where the snipped text came from so I didn't receive it any way, and I'm certainly not offended. I appreciate that many people have difficulty in finding the no parallax point and spend days over it. Yet I do find this surprising, given that all you have to do is to look into the lens with the aperture stopped down and view the entrance pupil directly. You can easily estimate its position to within a couple of mm just by using your two eyes. That's more than adequate in the present context.
John
Terry Duell
Nov 10, 2015, 9:09:11 PM11/10/15
to hugi...@googlegroups.com
Hello John,
On Wed, 11 Nov 2015 10:17:27 +1100, panostar <houghto...@gmail.com>
wrote:
>
> Terry,I haven't seen where the snipped text came from so I didn't receive
> it any way, and I'm certainly not offended.
Good.
> I appreciate that many people
> have difficulty in finding the no parallax point and spend days over it.
> Yet I do find this surprising, given that all you have to do is to look
> into the lens with the aperture stopped down and view the entrance pupil
> directly. You can easily estimate its position to within a couple of mm
> just by using your two eyes. That's more than adequate in the present
> context.
I just tried that with my 150-450 lens and the image of the diaphragm is
in quite different positions at 150mm FL, depending on which end of the
lens I'm viewing. My guess is a difference of about 75mm.
The locations come much closer together and move towards the camera as the
FL is increased.
Does that sound sensible, or am I on the wrong track with this?
On Wed, 11 Nov 2015 10:17:27 +1100, panostar <houghto...@gmail.com>
wrote:
>
> Terry,I haven't seen where the snipped text came from so I didn't receive
> it any way, and I'm certainly not offended.
> I appreciate that many people
> have difficulty in finding the no parallax point and spend days over it.
> Yet I do find this surprising, given that all you have to do is to look
> into the lens with the aperture stopped down and view the entrance pupil
> directly. You can easily estimate its position to within a couple of mm
> just by using your two eyes. That's more than adequate in the present
> context.
in quite different positions at 150mm FL, depending on which end of the
lens I'm viewing. My guess is a difference of about 75mm.
The locations come much closer together and move towards the camera as the
FL is increased.
Does that sound sensible, or am I on the wrong track with this?
panostar
Nov 11, 2015, 3:03:21 AM11/11/15
to hugin and other free panoramic software
On Wednesday, November 11, 2015 at 2:09:11 AM UTC, Tduell wrote:
> I appreciate that many people
> have difficulty in finding the no parallax point and spend days over it.
> Yet I do find this surprising, given that all you have to do is to look
> into the lens with the aperture stopped down and view the entrance pupil
> directly. You can easily estimate its position to within a couple of mm
> just by using your two eyes. That's more than adequate in the present
> context.
I just tried that with my 150-450 lens and the image of the diaphragm is
in quite different positions at 150mm FL, depending on which end of the
lens I'm viewing. My guess is a difference of about 75mm.
The locations come much closer together and move towards the camera as the
FL is increased.
Does that sound sensible, or am I on the wrong track with this?
Terry, Yes, you are on the right track. If you look into the front of the lens you see the entrance pupil. If you look into the rear of the lens you see the exit pupil. It's the entrance pupil that is located at the no parallax point. For some telephoto lenses at the longest focal length setting, the entrance pupil can even be behind the camera.
John
Markku Kolkka
Nov 11, 2015, 3:03:23 AM11/11/15
to hugi...@googlegroups.com
11.11.2015, 4:09, Terry Duell kirjoitti:
> I just tried that with my 150-450 lens and the image of the diaphragm is
> in quite different positions at 150mm FL, depending on which end of the
> lens I'm viewing.
The entrance pupil is the image of the aperture viewed from the _front_
> I just tried that with my 150-450 lens and the image of the diaphragm is
> in quite different positions at 150mm FL, depending on which end of the
> lens I'm viewing.
of the lens. https://en.wikipedia.org/wiki/Entrance_pupil
The location changes when zooming or focusing, so the position should be
calibrated with the focal length and focus distance you intend to use
for the actual photo shoot.
The position of the exit pupil (the image from back end) isn't relevant
for panorama photography.
--
Markku Kolkka
markku...@iki.fi
Terry Duell
Nov 11, 2015, 3:42:56 AM11/11/15
to hugi...@googlegroups.com
Hello John,
On Wed, 11 Nov 2015 19:03:21 +1100, panostar <houghto...@gmail.com>
wrote:
>
> Terry, Yes, you are on the right track. If you look into the front of
> the lens you see the entrance pupil. If you look into the rear of the
> lens you see the exit pupil. It's the entrance pupil that is located at
> the no
> parallax point. For some telephoto lenses at the longest focal length
> setting, the entrance pupil can even be behind the camera.
>
Thanks John.
On Wed, 11 Nov 2015 19:03:21 +1100, panostar <houghto...@gmail.com>
wrote:
>
> Terry, Yes, you are on the right track. If you look into the front of
> the lens you see the entrance pupil. If you look into the rear of the
> lens you see the exit pupil. It's the entrance pupil that is located at
> the no
> parallax point. For some telephoto lenses at the longest focal length
> setting, the entrance pupil can even be behind the camera.
>
bugbear
Nov 11, 2015, 4:07:16 AM11/11/15
to hugi...@googlegroups.com
Terry Duell wrote:
>
> I just tried that with my 150-450 lens and the image of the diaphragm is in quite different positions at 150mm FL, depending on which end of the lens I'm viewing. My guess is a difference of about 75mm.
> The locations come much closer together and move towards the camera as the FL is increased.
> Does that sound sensible, or am I on the wrong track with this?
I found my NPP empirically.
>
> I just tried that with my 150-450 lens and the image of the diaphragm is in quite different positions at 150mm FL, depending on which end of the lens I'm viewing. My guess is a difference of about 75mm.
> The locations come much closer together and move towards the camera as the FL is increased.
> Does that sound sensible, or am I on the wrong track with this?
I had already made the baseboard of my pano head (which is just a piece of wood
with a hole for a 1/4" bolt, which is what the camera fixes to).
http://s48.photobucket.com/user/bugbear33/media/pano_head.jpg.html
I'd pencilled the line of the axis of the lens (which is physically obvious)
onto the board.
(see attached diagram)
I put a panel pin into a piece of scrap, leaving just the head sticking out,
and put two AA batteries roughly in line, a couple of feet from
the camera, and 6 inches different in distance.
In other words, a subject with worst case parallax.
I then placed the board+camera onto the pin head,
somewhere on the line, and twisted the camera right-left.
There was, of course, lots of parallax movement of the two batteries,
visible in the viewfinder.
I simply moved the camera+board backward and forward
on the line, doing test pivots, until parallax was at a minimum.
Admittedly, a fully adjustable pano head would
allow you to find the NPP with more accuracy, but this
was easy and cheap.
BugBear
panostar
Nov 11, 2015, 6:12:28 AM11/11/15
to hugin and other free panoramic software
On Wednesday, November 11, 2015 at 9:07:16 AM UTC, bugbear wrote:
I put a panel pin into a piece of scrap, leaving just the head sticking out,
and put two AA batteries roughly in line, a couple of feet from
the camera, and 6 inches different in distance.
In other words, a subject with worst case parallax.
Snap! I did the same in 2002: http://www.johnhpanos.com/nodal.jpg . It's a good method for non-SLR cameras.
Except, your two batteries only 6 inches apart is far from being the worse case parallax. Both batteries will exhibit parallax shift and what you are seeing is the difference between these two shifts. It's better to compare the near battery with something as far away as possible. I use a window frame in the house across the road as the far reference point.
John
Reply all
Reply to author
Forward
0 new messages