Destorting a picture

[paulot...@gmail.com]

Hi I am still using Photoshop 7 but I am looking into CS5.5 or 6

I want to be able to distort a picture to rectify a distortion. What I mean is that in York (UK) we have a cathedral York Minster. To get a proper photograph to have to get close because of surrounding trees. Problem is it is a huge building so the camera has to be pointed up at an angle. This will cause the picture to be distorted. If I could rectify the pictur in Photoshop I could get the picture I want.

Any ideas on this please.

I do know that you can buy expensive cameras that can slide the lens upwards or downward to take the potograph but these are very rare and expensive.

TIA

Desmond.

[o...@two.three]

On Fri, 22 Feb 2013 16:39:58 +0000, paulot...@gmail.com wrote
(in article <ba835476-5236-407a...@googlegroups.com>):

> I want to be able to distort a picture to rectify a distortion. What I mean
> is that in York (UK) we have a cathedral York Minster. To get a proper
> photograph to have to get close because of surrounding trees. Problem is it
> is a huge building so the camera has to be pointed up at an angle. This will
> cause the picture to be distorted. If I could rectify the pictur in Photoshop

> I could get the picture I want.
>
> Any ideas on this please.

I assume the distortion you're referring to is converging verticals. If so,
here's a simple tutorial (not mine) for Photoshop 7 which may help:

http://www.crhfoto.co.uk/crh/convergingverticals.htm

[Savageduck]

What camera/lens combination are you using?

First there is no CS5.5, that was part of the creative suite for
specifically for creating graphics for use on mobile devices.

So if you have access to CS4, CS5, or CS6 they have the "Lens
Correction" filter which will allow you to correct using a camera/lens
profile, or manually correct for vertical or horizontal distortion. If
you shoot RAW the same corrections are available in Adobe Camera RAW or
ACR which is integral to the CS software.

Typical for shots of tall buildings is a base wider than the top, and
if you are taking the shot with the intent to fix it in software, make
sure that you leave yourself a reasonable amount of room around your
subject building (or any other subject) as there will be some cropping
to the original.

The first thing to do in the "Lens Correction" filter is to straighten
or level the building. Typically with a tall building use the
straighten tool by taking a line from the bottom center to the top
center of the structure. This should straighten it in the frame.

If you have grid lines active you should now be able to see any
"barrel" or "pin cushion" distortion imparted by the lens you are using
and you should correct for that approximately by checking against the
grid lines.

Next, go to "custom" and adjust the vertical distortion appropriately.
Don't over do this, remember your eye/camera position is just that, and
if you were viewing from that level you would experience some
"vanishing point" perspective effect. Your camera is not at some
phantom point midway between the top and bottom of the building. Even
with a "tilt-shift" lens you would not be able to full compensate for
camera position.

Once you have made that vertical distortion adjustment, if you wer not
square to the building when you shot check the horizontal distortion.

Finally, recheck the "pincushion" and "barrel" distortion correction,
and apply the filter.

--
Regards,

Savageduck

[paulot...@gmail.com]

I have a basic Sony Alpha and I have a 16-70mm lens (Lager lenses also) I can only go down to 18 as the picture starts to distort I would have to get 25 feet (ish) from it so would have to point the camera upwards. Can't afford fish eye but that distorts anyway.. Would Photoshop 7 work or not?

[paulot...@gmail.com]

I have access to CS5.5 but can't understand why this does not have Lens Correction but CS4,5 and 6 does. Crazy :(

[paulot...@gmail.com]

On Saturday, 23 February 2013 11:52:44 UTC, paulot...@gmail.com wrote:

Sorry Sony Alpha 200. Must get this info right. Too early in the morning.

[Savageduck]

PS-7 does not have the "Lens Correction" filter.

OK. I got that you are using a Sony Alpha 200 with a 16-70mm lens, 16mm
being the widest focal length you have available. Shooting a tall
building from approximately 25 feet seems way too close to me. You
would definitely be aiming at an acute upward angle. As I am not
familiar with the location and the building you are trying to shoot,
all I can suggest is to select an optimal vantage point further away,
but I realize that might not be possible. So shooting as wide as
possible, and correction any distortion with CS4/5/6 might be your only
option.
You can refer to my prior response for the workflow I might use with
the "Lens Correction" filter. As always your mileage might vary.

> I have access to CS5.5 but can't understand why this does not have Lens Cor
> rection but CS4,5 and 6 does. Crazy :(

CS5.5 is not Photoshop, or even part of Photoshop. It is part of the
Creative Suite and is intended as an update for Adobe "Indesign CS5"
specifically for graphics design for mobile devices.

There is no Photoshop CS5.5.

It would also help if we had a visual idea of you problem, so that
those of us familiar with making distortion corrections with PS could
see if that would be a workable solution.
So if you use Dropbox or any other method of sharing your images you
could post a link to one of your problematic image captures like this.
< https://dl.dropbox.com/u/1295663/FileChute/screenshot_132.jpg >


--
Regards,

Savageduck

[Savageduck]

Never mind. I checked on your seeing exactly what you are dealing with,
and Google was able to provide a batch of images:
<
http://www.google.com/search?q=york+minster+abbey&hl=en&client=safari&rls=en&source=lnms&tbm=isch&sa=X&ei=P88oUZWcIMKdiQKci4DQDQ&ved=0CAoQ_AUoAQ&biw=1845&bih=951
>
or
< http://tinyurl.com/ac5safb >

...and from what I can see, your problem is a case of, location,
location, location.


--
Regards,

Savageduck

[Savageduck]

...and even the best of those needed some straightening and vertical
distortion tweaks.
< https://dl.dropbox.com/u/1295663/FileChute/screenshot_133.jpg >


--
Regards,

Savageduck

[Savageduck]

I also checked with Google Earth, Street View, and there is a decent
vantage point further away, up Duncombe Place.
< https://dl.dropbox.com/u/1295663/FileChute/screenshot_134.jpg >


--
Regards,

Savageduck

[o...@two.three]

On Sat, 23 Feb 2013 14:41:28 +0000, Savageduck wrote
(in article <2013022306412816708-savageduck1@REMOVESPAMmecom>):

>> ...and from what I can see, your problem is a case of, location,
>> location, location.
>
> ...and even the best of those needed some straightening and vertical
> distortion tweaks.
> < https://dl.dropbox.com/u/1295663/FileChute/screenshot_133.jpg >
>

Savageduck quacks much sense and I would only add that how fussy you have to
be depends on what your photograph is for. If it will end up as a relatively
small jpeg on a web site then tweaking should be adequate; if it's going to
be published in a glossy magazine then hiring an architectural camera/lens
and reshooting might be necessary.

Here's my take on more or less eliminating the converging verticals on a
screen grab from Street View. It only took two minutes to do and is by no
means perfect but I'd be happy to put it on a web site.

https://www.dropbox.com/s/gfo07har1yf0paz/yorkminster.jpg

And, finally, it's some years since I visited York Minster but it is a very
impressive building - more than 20 storeys high. It's scarcely believable
that it was built in the 14th/15th centuries (no hard hats then).

[Wilfried]

Hello!

I have a different suggestion (which I already applied several times).

Make a panorama photo:

Set the camera at medium focal length and shoot a series of pictures
overlapping each other so that the entire building and enough space
around is captured. Pay attention to only _turn_ the camera from one
picture to the next, _do_not_move_ the camera horizontally or
vertically.

Install a panorama photo software - I use http://hugin.sourceforge.net
which is open source and free.

hugin can automagically detect horizontal and vertical lines and make a
decent "distortion" to get them right.

hope that helps
--
Wilfried Hennings
please reply in the newsgroup, the e-mail address is invalid

[Savageduck]

On 2013-02-25 04:37:33 -0800, Wilfried <Wilf...@invalid.invalid> said:

> paulot...@gmail.com wrote:
>
>> Hi I am still using Photoshop 7 but I am looking into CS5.5 or 6
>>
>> I want to be able to distort a picture to rectify a distortion. What I
>> mean is that in York (UK) we have a cathedral York Minster. To get a
>> proper photograph to have to get close because of surrounding trees.
>> Problem is it is a huge building so the camera has to be pointed up at
>> an angle. This will cause the picture to be distorted. If I could
>> rectify the pictur in Photoshop I could get the picture I want.
>>
>> Any ideas on this please.
>>
>> I do know that you can buy expensive cameras that can slide the lens
>> upwards or downward to take the potograph but these are very rare and
>> expensive.
>
> Hello!
>
> I have a different suggestion (which I already applied several times).
>
> Make a panorama photo:
>
> Set the camera at medium focal length and shoot a series of pictures
> overlapping each other so that the entire building and enough space
> around is captured. Pay attention to only _turn_ the camera from one
> picture to the next, _do_not_move_ the camera horizontally or
> vertically.

...and how are you going to achieve turning the camera without moving
it horizontally or vertically?

Keeping the camera on an even plain, either horizontally or vertically,
is a different issue. Consider having the camera tripod mounted
(preferably on a pano-head) now the camera can be rotated around a
fixed point, either horizontally or vertically.

> Install a panorama photo software - I use http://hugin.sourceforge.net
> which is open source and free.
>
> hugin can automagically detect horizontal and vertical lines and make a
> decent "distortion" to get them right.

Only if the overlaid mosaic images are a match for one of the stitching
algorithms provided by the software.

> hope that helps

Even with decent software a pano of a tall structure would be tough to
produce without stepped distortion using the technique you outlined.
Consider, your camera would be at eye, or tripod level above ground.
Your capture of each shot for your panorama would be from top to
bottom, or bottom to top. This gives you a displaced point of rotation.
To create a good "vertical" pano your ideal shooting vantage point
would need to be at a point midway between ground level and the top of
the building. In the case of the structure at York Minster, the Western
front is 196ft/60M tall, so find a position about 98ft/30M above the
ground to shoot your vertical pano. Then you should be able to stitch
the pano with Hugin, or Photoshop, or any other pano software, and get
a decent distortion correction.

The real solution here is to use a "tilt-shift" lens, or a wide angle
and fix any lens distortion in post.

--
Regards,

Savageduck

[Wilfried]

You don't beleave me?
Here http://www.awh-ew.de/images/static/IMGP0562.JPG is a picture I made
standing on the ground level at the side of the church. From there I
made a series of 6 pictures (free-hand) and stitched them with hugin.

[Savageduck]

You sure did a questionable job of fixing the distortion generated by
your pano for the top of the tower and the clock face.
This is not what is needed when shooting tall buildings. Squashing the
tower and introducing a very obvious kink, twist, and lean is not in my
opinion acceptable.

BTW: What happened to the top of the tower? This is supposed to be
trying to find a solution to capture a tall building, minimizing
distortion, not capturing the side of a building and distorting the
tall structures of that building, including decapitating it.

--
Regards,

Savageduck

[Wilfried]

I accidently missed to take another row of pictures high enough to
capture the top.

[paulot...@aol.com]

On Saturday, 23 February 2013 14:08:57 UTC, Savageduck wrote:

Hi been a long time sinc I got back to this. There have been some interesting links one from two.three

York Minster facts
Length - 525 feet (160 meters)
Width - 249 feet (76 meters)
Height to vault - 88.5 feet (27 meters)
West towers - Nearly 184 feet each (56 meters)
Lantern tower - 233 feet (71 meters)
Pictue of church
http://www.photographers-resource.co.uk/A_heritage/Abbeys/LG/York_Minster.htm

As you can see not an easy one to take in a built up city.

[paulot...@aol.com]

Yes Duncan place is good if someone will chop all the trees down. I have to get past the trees which will make it a close shot or wait untill winter when there are no leaves on the trees. PS7 does have it. I folowed the tutorial o.. gave and it worked

Wilfried

Can't see how taking muli pictures woluld work. I have to use a spirit level to make sure the angle is the same moving the camera around would also cause a horizontal distortion also I think.

[paulot...@aol.com]

Wanted to put up 3 images of my fist attempt. Only options [Post] [Discard] Image upload not available. Strange :(

[Savageduck]

On 2013-03-21 10:39:45 -0700, paulot...@aol.com said:
>
> Wanted to put up 3 images of my fist attempt. Only options [Post]
> [Discard] Image upload not available. Strange :(

How are you attempting to post images?
Are you using an image hosting site such as Flickr, or are you using a
"Cloud" service such as Dropbox or G-Drive?

If you are trying to upload a binary image file to this NG, understand
that comp.graphics.apps.photoshop is not a binaries group.


--
Regards,

Savageduck

[paulot...@aol.com]

On Friday, 22 February 2013 16:39:58 UTC, paulot...@gmail.com wrote:

No I simply click on reply. I have a text box to type my reply. I have above and below GREEN Post and GREY Discard.
When I first posted there was a section underneth Manage atachments. Even as I am typing this now there is no manage atachments button showing.
:(