Rokinon 12mm 2.8 ED AS NCS Fisheye
105 views
Skip to first unread message
Pablo Betancourt
Aug 19, 2023, 12:20:46 PM8/19/23
to PTGui Support
Hello friends, I'm having trouble trying to stitch the images of this lens, which I'm using it with a sigma adaptader in a Sony A7rIII and a nodal ninja 5, properly calibrated.
%2021.15.59.jpg?part=0.1&view=1)
I use to work with a sigma 15mm ex and the results were pretty good on the first try and the optical quality was superb. Unfortunately I dropped it and scratched the glass. As I cannot get a new one yet, I bought this rokinon as an alternative but it seems as if PTGUI does not recognize the distortion of this lens pretty well. I'm getting a lot of stitching errors even after masking, deletting worst points, optimizing, etc. Any help appreciated
Here are jpgs of the photos in case anyone can want to try it:
Erik Krause
Aug 19, 2023, 12:58:33 PM8/19/23
to pt...@googlegroups.com
Am 19.08.2023 um 03:57 schrieb Pablo Betancourt:
> Here are jpgs of the photos in case anyone can want to try it:
> https://www.dropbox.com/scl/fo/fve5nznyhny6takvocl5h/h?rlkey=38kuhrtmi9dyw397icgp39oz9&dl=0
I dropped the images on PTGui 12. It asked me to set the focal length. I
> Here are jpgs of the photos in case anyone can want to try it:
> https://www.dropbox.com/scl/fo/fve5nznyhny6takvocl5h/h?rlkey=38kuhrtmi9dyw397icgp39oz9&dl=0
entered 12mm and chose Samyang/Rokinon/Bower 12mm /2.8 under Lens Type.
After "Align Images" I got a perfect stitch. Find the project file attached.
BTW.: You should remove chromatic aberration (best during raw
conversion) to improve your result.
--
Erik Krause
http://www.erik-krause.de
Pablo Betancourt
Aug 19, 2023, 6:24:23 PM8/19/23
to PTGui Support
Wow, that's great! so the issue is that I haven't that lens in my database. Where did you get that data from?
John Houghton
Aug 20, 2023, 8:35:39 AM8/20/23
to PTGui Support
Pablo, Erik explained how he got the lens data (after loading the images, enter focal length as 12mm and select the 12mm Bower lens from the pull down menu). You can save the settings in your lens database on the Lens Settings tab so you can load them in for future runs. Do this after getting a satisfactory alignment.
Just one observation: one of the nadir images is upside down:
As you rotate the head around through 180 degrees, the vertical arm should remain in the same position in the images. Here, it switches over from the left to the right. The usual reason for this is that the camera's orientation sensor fails to deliver reliable data when the camera is pointing directly down (or up), since gravity is acting at right angles to the image sensor. As a result, there can be problems in the optimization of the lens distortion correction parameters. The lens shift parameters correct for the optical axis of the lens not being exactly aligned with the centre point of the image frame. For the upside down image, the position of the optical centre is inconsistent with the other images, so it should not share the same global shift parameters in the optimization. To handle this: on the Lens Settings tab, select Individual Lens Shift parameters for the inconsistent image. Not knowing which image was upside down, I selected individual lens shift parameters for both nadir images and saw the optimization figures improve from 4 average, 93 maximum to 2 average and 7.5 maximum. Clearly a worthwhile change, but consider turning off the auto rotate feature in the camera to avoid the problem.
John
Pablo Betancourt
Aug 20, 2023, 11:08:01 AM8/20/23
to PTGui Support
Many thanks John,
%2012.06.17.jpg?part=0.1&view=1)
the reason I asked Erik is becasue I cannot find the 12mm Bower lens in any pull down menu. It was till now, that I have his project , that I could save those values in my lens database.
But again my question is where does PTGUI this database from? I don't have any, just my old sigma 8mm that I don't remember wher I get from
Pablo Betancourt
Aug 20, 2023, 11:18:23 AM8/20/23
to PTGui Support
"As you rotate the head around through 180 degrees, the vertical arm should remain in the same position in the images. Here, it switches over from the left to the right. The usual reason for this is that the camera's orientation sensor fails to deliver reliable data when the camera is pointing directly down (or up), since gravity is acting at right angles to the image sensor. As a result, there can be problems in the optimization of the lens distortion correction parameters. The lens shift parameters correct for the optical axis of the lens not being exactly aligned with the centre point of the image frame. For the upside down image, the position of the optical centre is inconsistent with the other images, so it should not share the same global shift parameters in the optimization. To handle this: on the Lens Settings tab, select Individual Lens Shift parameters for the inconsistent image. Not knowing which image was upside down, I selected individual lens shift parameters for both nadir images and saw the optimization figures improve from 4 average, 93 maximum to 2 average and 7.5 maximum. Clearly a worthwhile change, but consider turning off the auto rotate feature in the camera to avoid the problem."
I'm not sure if I understand this completely. I turn 180° my panohead and take two photos so I can get part of the ground that it's hidden from the vertical arm of the nodal ninja.I understand that this may conduct to some issues but to my experience I'm always having perfect results with this method. I even take a couple of hand held photos without the tripod, an then Ptgui algin that perfectly with proper masking, even if the parallax is huge. I don't know if this affects the rest of the image and that is what you are trying to explain me... I'm sorry for my poor knowledge.
PTGui Support
Aug 20, 2023, 5:03:04 PM8/20/23
to pt...@googlegroups.com
Hi Pablo,
On almost every camera (but in particular with interchangable lenses)
the lens is not mounted exactly centered in front of the image sensor.
PTGui applies a correction for this lens shift; by default the same
correction is applied to all images. However for your nadir image PTGui
wasn't able to figure out if the image was rotated 90 degrees clockwise
or counterclockwise from the other images. If it gets this wrong, the
lens shift correction is applied in the wrong direction, causing higher
control point errors. It's not related to parallax.
You can overcome this by applying individual shift correction to the
affected images as John explains.
Kind regards,
Joost Nieuwenhuijse
www.ptgui.com
On 20-08-2023 17:18, Pablo Betancourt wrote:
> /"As you rotate the head around through 180 degrees, the vertical arm
> /
> /
> https://www.dropbox.com/scl/fo/fve5nznyhny6takvocl5h/h?rlkey=38kuhrtmi9dyw397icgp39oz9&dl=0 <https://www.dropbox.com/scl/fo/fve5nznyhny6takvocl5h/h?rlkey=38kuhrtmi9dyw397icgp39oz9&dl=0>
>
> --
> You received this message because you are subscribed to the Google
> Groups "PTGui Support" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to ptgui+un...@googlegroups.com
> <mailto:ptgui+un...@googlegroups.com>.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/ptgui/28abcc6d-7d24-4a98-a7f5-514a59d780bfn%40googlegroups.com <https://groups.google.com/d/msgid/ptgui/28abcc6d-7d24-4a98-a7f5-514a59d780bfn%40googlegroups.com?utm_medium=email&utm_source=footer>.
On almost every camera (but in particular with interchangable lenses)
the lens is not mounted exactly centered in front of the image sensor.
PTGui applies a correction for this lens shift; by default the same
correction is applied to all images. However for your nadir image PTGui
wasn't able to figure out if the image was rotated 90 degrees clockwise
or counterclockwise from the other images. If it gets this wrong, the
lens shift correction is applied in the wrong direction, causing higher
control point errors. It's not related to parallax.
You can overcome this by applying individual shift correction to the
affected images as John explains.
Kind regards,
Joost Nieuwenhuijse
www.ptgui.com
On 20-08-2023 17:18, Pablo Betancourt wrote:
> /"As you rotate the head around through 180 degrees, the vertical arm
> should remain in the same position in the images. Here, it switches
> over from the left to the right. The usual reason for this is that the
> camera's orientation sensor fails to deliver reliable data when the
> camera is pointing directly down (or up), since gravity is acting at
> right angles to the image sensor. As a result, there can be problems in
> the optimization of the lens distortion correction parameters. The lens
> shift parameters correct for the optical axis of the lens not being
> exactly aligned with the centre point of the image frame. For the
> upside down image, the position of the optical centre is inconsistent
> with the other images, so it should not share the same global shift
> parameters in the optimization. To handle this: on the Lens Settings
> tab, select Individual Lens Shift parameters for the inconsistent
> image. Not knowing which image was upside down, I selected individual
> lens shift parameters for both nadir images and saw the optimization
> figures improve from 4 average, 93 maximum to 2 average and 7.5
> maximum. Clearly a worthwhile change, but consider turning off the auto
> rotate feature in the camera to avoid the problem."/
> over from the left to the right. The usual reason for this is that the
> camera's orientation sensor fails to deliver reliable data when the
> camera is pointing directly down (or up), since gravity is acting at
> right angles to the image sensor. As a result, there can be problems in
> the optimization of the lens distortion correction parameters. The lens
> shift parameters correct for the optical axis of the lens not being
> exactly aligned with the centre point of the image frame. For the
> upside down image, the position of the optical centre is inconsistent
> with the other images, so it should not share the same global shift
> parameters in the optimization. To handle this: on the Lens Settings
> tab, select Individual Lens Shift parameters for the inconsistent
> image. Not knowing which image was upside down, I selected individual
> lens shift parameters for both nadir images and saw the optimization
> figures improve from 4 average, 93 maximum to 2 average and 7.5
> maximum. Clearly a worthwhile change, but consider turning off the auto
> /
> /
> I'm not sure if I understand this completely. I turn 180° my panohead
> and take two photos so I can get part of the ground that it's hidden
> from the vertical arm of the nodal ninja.I understand that this may
> conduct to some issues but to my experience I'm always having perfect
> results with this method. I even take a couple of hand held photos
> without the tripod, an then Ptgui algin that perfectly with proper
> masking, even if the parallax is huge. I don't know if this affects the
> rest of the image and that is what you are trying to explain me... I'm
> sorry for my poor knowledge.
>
> El domingo, 20 de agosto de 2023 a la(s) 12:08:01 UTC-3, Pablo
> Betancourt escribió:
>
> Many thanks John,
>
> the reason I asked Erik is becasue I cannot find the 12mm Bower lens
> in any pull down menu. It was till now, that I have his project ,
> that I could save those values in my lens database.
> But again my question is where does PTGUI this database from? I
> don't have any, just my old sigma 8mm that I don't remember wher I
> get from
> and take two photos so I can get part of the ground that it's hidden
> from the vertical arm of the nodal ninja.I understand that this may
> conduct to some issues but to my experience I'm always having perfect
> results with this method. I even take a couple of hand held photos
> without the tripod, an then Ptgui algin that perfectly with proper
> masking, even if the parallax is huge. I don't know if this affects the
> rest of the image and that is what you are trying to explain me... I'm
> sorry for my poor knowledge.
>
> El domingo, 20 de agosto de 2023 a la(s) 12:08:01 UTC-3, Pablo
> Betancourt escribió:
>
> Many thanks John,
>
> the reason I asked Erik is becasue I cannot find the 12mm Bower lens
> in any pull down menu. It was till now, that I have his project ,
> that I could save those values in my lens database.
> But again my question is where does PTGUI this database from? I
> don't have any, just my old sigma 8mm that I don't remember wher I
> get from
> Captura de pantalla 2023-08-20 a la(s) 12.06.17.jpg
>
>
> El domingo, 20 de agosto de 2023 a la(s) 09:35:39 UTC-3, John
> Houghton escribió:
>
> Pablo, Erik explained how he got the lens data (after loading
> the images, enter focal length as 12mm and select the 12mm Bower
> lens from the pull down menu). You can save the settings in
> your lens database on the Lens Settings tab so you can load them
> in for future runs. Do this after getting a satisfactory alignment.
>
> Just one observation: one of the nadir images is upside down:
>
>
>
> El domingo, 20 de agosto de 2023 a la(s) 09:35:39 UTC-3, John
> Houghton escribió:
>
> Pablo, Erik explained how he got the lens data (after loading
> the images, enter focal length as 12mm and select the 12mm Bower
> lens from the pull down menu). You can save the settings in
> your lens database on the Lens Settings tab so you can load them
> in for future runs. Do this after getting a satisfactory alignment.
>
> Just one observation: one of the nadir images is upside down:
>
>
> I dropped the images on PTGui 12. It asked me to set the
> focal length. I
> entered 12mm and chose Samyang/Rokinon/Bower 12mm /2.8
> under Lens Type.
> After "Align Images" I got a perfect stitch. Find the
> project file attached.
>
> BTW.: You should remove chromatic aberration (best
> during raw
> conversion) to improve your result.
>
> --
> Erik Krause
> http://www.erik-krause.de <http://www.erik-krause.de>
> I dropped the images on PTGui 12. It asked me to set the
> focal length. I
> entered 12mm and chose Samyang/Rokinon/Bower 12mm /2.8
> under Lens Type.
> After "Align Images" I got a perfect stitch. Find the
> project file attached.
>
> BTW.: You should remove chromatic aberration (best
> during raw
> conversion) to improve your result.
>
> --
> Erik Krause
>
> --
> You received this message because you are subscribed to the Google
> Groups "PTGui Support" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to ptgui+un...@googlegroups.com
> <mailto:ptgui+un...@googlegroups.com>.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/ptgui/28abcc6d-7d24-4a98-a7f5-514a59d780bfn%40googlegroups.com <https://groups.google.com/d/msgid/ptgui/28abcc6d-7d24-4a98-a7f5-514a59d780bfn%40googlegroups.com?utm_medium=email&utm_source=footer>.
Pablo Betancourt
Aug 20, 2023, 6:23:00 PM8/20/23
to PTGui Support
Understood ! many thanks for the explanation.
%2019.16.18.jpg?part=0.1&view=1)
So the only question I still have is how do you get the data from a lens like mine.
I mean, these parameters were the ones that Erik gave me in his project file:
But, where does he get that data from?
PTGui Support
Aug 21, 2023, 6:37:41 AM8/21/23
to pt...@googlegroups.com
The values were calculated by PTGui. Just run the optimizer.
> https://www.dropbox.com/scl/fo/fve5nznyhny6takvocl5h/h?rlkey=38kuhrtmi9dyw397icgp39oz9&dl=0 <https://www.dropbox.com/scl/fo/fve5nznyhny6takvocl5h/h?rlkey=38kuhrtmi9dyw397icgp39oz9&dl=0> <https://www.dropbox.com/scl/fo/fve5nznyhny6takvocl5h/h?rlkey=38kuhrtmi9dyw397icgp39oz9&dl=0 <https://www.dropbox.com/scl/fo/fve5nznyhny6takvocl5h/h?rlkey=38kuhrtmi9dyw397icgp39oz9&dl=0>>
On 21-08-2023 00:23, Pablo Betancourt wrote:
> Understood ! many thanks for the explanation.
>
> So the only question I still have is how do you get the data from a lens
> like mine.
> I mean, these parameters were the ones that Erik gave me in his project
> file:
>
>
> Understood ! many thanks for the explanation.
>
> So the only question I still have is how do you get the data from a lens
> like mine.
> I mean, these parameters were the ones that Erik gave me in his project
> file:
>
>
> Captura de pantalla 2023-08-20 a la(s) 19.16.18.jpg
> But, where does he get that data from?
>
> El domingo, 20 de agosto de 2023 a la(s) 18:03:04 UTC-3, PTGui Support
> escribió:
>
> Hi Pablo,
>
> On almost every camera (but in particular with interchangable lenses)
> the lens is not mounted exactly centered in front of the image sensor.
>
> PTGui applies a correction for this lens shift; by default the same
> correction is applied to all images. However for your nadir image PTGui
> wasn't able to figure out if the image was rotated 90 degrees clockwise
> or counterclockwise from the other images. If it gets this wrong, the
> lens shift correction is applied in the wrong direction, causing higher
> control point errors. It's not related to parallax.
>
> You can overcome this by applying individual shift correction to the
> affected images as John explains.
> Kind regards,
>
> Joost Nieuwenhuijse
> www.ptgui.com <http://www.ptgui.com>
> But, where does he get that data from?
>
> El domingo, 20 de agosto de 2023 a la(s) 18:03:04 UTC-3, PTGui Support
> escribió:
>
> Hi Pablo,
>
> On almost every camera (but in particular with interchangable lenses)
> the lens is not mounted exactly centered in front of the image sensor.
>
> PTGui applies a correction for this lens shift; by default the same
> correction is applied to all images. However for your nadir image PTGui
> wasn't able to figure out if the image was rotated 90 degrees clockwise
> or counterclockwise from the other images. If it gets this wrong, the
> lens shift correction is applied in the wrong direction, causing higher
> control point errors. It's not related to parallax.
>
> You can overcome this by applying individual shift correction to the
> affected images as John explains.
> Kind regards,
>
> Joost Nieuwenhuijse
> >
> > I dropped the images on PTGui 12. It asked me to set the
> > focal length. I
> > entered 12mm and chose Samyang/Rokinon/Bower 12mm /2.8
> > under Lens Type.
> > After "Align Images" I got a perfect stitch. Find the
> > project file attached.
> >
> > BTW.: You should remove chromatic aberration (best
> > during raw
> > conversion) to improve your result.
> >
> > --
> > Erik Krause
> > http://www.erik-krause.de <http://www.erik-krause.de>
> <http://www.erik-krause.de <http://www.erik-krause.de>>
> >
> > --
> > You received this message because you are subscribed to the Google
> > Groups "PTGui Support" group.
> > To unsubscribe from this group and stop receiving emails from it,
> send
> > an email to ptgui+un...@googlegroups.com
> > <mailto:ptgui+un...@googlegroups.com>.
> > To view this discussion on the web visit
> >
> https://groups.google.com/d/msgid/ptgui/28abcc6d-7d24-4a98-a7f5-514a59d780bfn%40googlegroups.com <https://groups.google.com/d/msgid/ptgui/28abcc6d-7d24-4a98-a7f5-514a59d780bfn%40googlegroups.com> <https://groups.google.com/d/msgid/ptgui/28abcc6d-7d24-4a98-a7f5-514a59d780bfn%40googlegroups.com?utm_medium=email&utm_source=footer <https://groups.google.com/d/msgid/ptgui/28abcc6d-7d24-4a98-a7f5-514a59d780bfn%40googlegroups.com?utm_medium=email&utm_source=footer>>.
> > I dropped the images on PTGui 12. It asked me to set the
> > focal length. I
> > entered 12mm and chose Samyang/Rokinon/Bower 12mm /2.8
> > under Lens Type.
> > After "Align Images" I got a perfect stitch. Find the
> > project file attached.
> >
> > BTW.: You should remove chromatic aberration (best
> > during raw
> > conversion) to improve your result.
> >
> > --
> > Erik Krause
> > http://www.erik-krause.de <http://www.erik-krause.de>
> <http://www.erik-krause.de <http://www.erik-krause.de>>
> >
> > --
> > You received this message because you are subscribed to the Google
> > Groups "PTGui Support" group.
> > To unsubscribe from this group and stop receiving emails from it,
> send
> > an email to ptgui+un...@googlegroups.com
> > <mailto:ptgui+un...@googlegroups.com>.
> > To view this discussion on the web visit
> >
>
> --
> You received this message because you are subscribed to the Google
> Groups "PTGui Support" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to ptgui+un...@googlegroups.com
> <mailto:ptgui+un...@googlegroups.com>.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/ptgui/3ae70210-240e-4891-bcbf-020182e15062n%40googlegroups.com <https://groups.google.com/d/msgid/ptgui/3ae70210-240e-4891-bcbf-020182e15062n%40googlegroups.com?utm_medium=email&utm_source=footer>.
> --
> You received this message because you are subscribed to the Google
> Groups "PTGui Support" group.
> To unsubscribe from this group and stop receiving emails from it, send
> an email to ptgui+un...@googlegroups.com
> <mailto:ptgui+un...@googlegroups.com>.
> To view this discussion on the web visit
Erik Krause
Aug 22, 2023, 5:25:45 AM8/22/23
to pt...@googlegroups.com
Am 20.08.23 um 17:08 schrieb Pablo Betancourt:
> But again my question is where does PTGUI this database from?
From your screenshot I can deduce, that you use PTGui 12 pro. Correct
me if I'm wrong.
PTGui 12 has two lens databases, a built-in one with fisheye lenses only
and a user defined one.
Usually, if you drop images on PTGui without focal length in exif data,
you get a dialog asking for the focal length. If you enter 12 in this
dialog, you get a dropdown list (just below) with fisheye lenses that
fit more or less. The Rokinon (which can also be labelled Samyang, Bower
etc.) should be in this list.
--
Erik Krause
> But again my question is where does PTGUI this database from?
me if I'm wrong.
PTGui 12 has two lens databases, a built-in one with fisheye lenses only
and a user defined one.
Usually, if you drop images on PTGui without focal length in exif data,
you get a dialog asking for the focal length. If you enter 12 in this
dialog, you get a dropdown list (just below) with fisheye lenses that
fit more or less. The Rokinon (which can also be labelled Samyang, Bower
etc.) should be in this list.
--
Erik Krause
Pablo Betancourt
Aug 23, 2023, 1:49:02 PM8/23/23
to PTGui Support
Yes Erik, I use PTGui Pro. I finally found that database! Thank you very much!
Reply all
Reply to author
Forward
0 new messages