Can I do perspective correction on just part?

Canon 12x IS USM (S3 IS built-in Lens) -- 36-432mm (35mm EQ)

05/20/2012 12:43:25 PM · #1

Can I do perspective correction on just part of the photo? In other words, can I correct the perspective on a building but leave the surrounding as is?

(advanced editing)

GeneralE

Canon PowerShot S3 IS

05/20/2012 12:46:59 PM · #2

You are allowed if you are capable ... :-)

AllenP

Canon EOS-1D X Mark II

Canon EF 85mm f/1.2L II USM

05/20/2012 01:00:59 PM · #3

Are you asking if you are allowed to do it in a challenge or how to do it? I believe a minor perspective correction is definitely allowed in advanced even if it is applied to parts of the photograph.

Message edited by author 2012-05-20 13:35:16.

05/20/2012 02:00:02 PM · #4

Originally posted by AllenP:

Are you asking if you are allowed to do it in a challenge or how to do it? I believe a minor perspective correction is definitely allowed in advanced even if it is applied to parts of the photograph.

For a challenge.

When I correct the perspective on the whole thing, it does funky things to other parts of the photo. So I want to do a perspective correction only on the center part of the photo, and leave the outer 3rd untouched. For some reason I'm thinking this is illegal, but I'm not sure.

Fujifilm XF 18-55mm f/2.8-4 OIS

05/20/2012 02:00:45 PM · #5

Originally posted by GeneralE:

You are allowed if you are capable ... :-)

that's definitely part of the question. :)

The other part is "may I"?

mariuca

Fujifilm X-T30

05/20/2012 02:09:13 PM · #6

I always thout that it's not allowed in advanced ed'g as part of "do not use distortions to create new effects or radically alter objects." Which is not your case. But I never did it for challenges. It seems to be legal.
For non challenges, I often use "skew" to correct architecture.

Bear_Music

Samsung Galaxy S24, S24+, S24 Ultra

Sony 24-70mm F4 Vario-Tessar T* FE OSS

05/20/2012 02:18:20 PM · #7

It is allowed to use Perspective and Skew adjustments to square up verticals/horizontals and correct for converging lines in buildings, piers, and the like, for sure. In advanced editing, anyway... Not basic...

But I'm not sure I'm understanding Wendy's question correctly. I'm not aware of any way to selectively apply those controls to just a portion of a layer. It sounds to me like she's saying she wants to square up the building (or whatever it is) and leave all the trees and shrubbery and stuff alone. And as far as I know the only way to do THAT is to copy the layer, adjust the whole copy, then mask out the parts you don't want to be included, letting the unaltered underlayer show through. Basically the same thing as cutting out the building, squaring it up, and pasting it in the picture.

Is THAT legal? I don't know...

R.

Canon 12x IS USM (S3 IS built-in Lens) -- 36-432mm (35mm EQ)

05/20/2012 02:42:41 PM · #8

Originally posted by Bear_Music:

yes -- that's exactly what I'm asking, Bear.

GeneralE

Canon PowerShot S3 IS

05/20/2012 02:51:51 PM · #9

I did say before that I (personally) thought it was legal, if used to "correct" an optical distortion, not to "create an effect" ... but as Bear has pointed out, it may be harder to accomplish than to imagine.

However, it's almost impossible to give any kind of reliable opinion on (necessarily) vaguely-described hypotheticals ... as always, you are advised to submit a ticket with your editing steps and attach "before and after" versions so that at least a couple of people can see exactly what you're trying to do.

yanko

Canon EOS-5D Mark II

Carl Zeiss 50mm ZE f/1.4 Planar T for Canon

05/20/2012 04:01:35 PM · #10

Originally posted by Bear_Music:

Or make a selection of the area first and then do the transforming. However, that tends to cause gaps or overlaps to form in the image, which you'll then have to fix. That said, I'm a little puzzled as to why she would be needing to do this at all. You should be able to fix perspective problems without having to resort to this. Perhaps the problem is the particular tool being used? I almost always use the Distort transform at some point in the process since that gives you more flexibility than Skew or Perspective transform. However, without being able to see and work on the image it's hard to tell what the right tool is for the job or how it should be used.

Message edited by author 2012-05-20 16:02:53.

Mike

Canon EOS-5D Mark II

Tamron SP 24-70mm f/2.8 Di VC USD Canon Mount

05/20/2012 08:59:46 PM · #11

im curious as to why you even need to, is perspective correction you want or are you trying to fix lens distortion?

Tamron SP 24-70mm f/2.8 Di VC USD Canon Mount

05/20/2012 09:27:26 PM · #12

Ok -- so since people were wondering, since the question is no longer pertinent for tonight, but since it's an interesting discussion:

When I was looking at Ansel Adams photos, he used longer lenses for structures, etc, so there wasn't the perspective problem with short lenses.

I had this shot:

But I didn't want the building leaning back. So I tried to fix it. (poorly, I know, but you get the idea)

But I didn't like what it did to the tree and the path on the left -- they both seemed to be falling out of the picture.

So I was wondering if I could leave the background, and change the perspective on the building alone.

But it puts things in different places, yet we're allowed to select and we're allowed to play with perspective, etc, are we allowed to do both?

Message edited by author 2012-05-20 21:27:55.

Mike

Canon EOS-5D Mark II

05/20/2012 09:46:49 PM · #13

did you try taking the second picture and remove the distortion created to the tree with a wide angle lens correction.