[Dabhand16]

Leading on from a discussion in the sharing forum, has anyone found that after making lens corrections, particularly big corrections, if the perspective of the shot has been compressed?

I've been using two ways of correcting verticals in PS. First is the 'proper' lens correction filter, and this was the way I did the corrections at first. It keeps everything true and as the frame tilts, the subject tends to go out of shot at the top unless you stop the correction early and keep some convergence. I've made a mental note to leave plenty of space at the top in future!

Here is an example



You will see that the top of the image has been lost. The original shot is here



The second way is to use the free transform tool. This will correct the verticals but will also leave the height unchanged, and you then have to stretch the image vertically to put back the proportions.

This is one using this method



here is the original - warts and all!



It may well be that both of these methods will remove some perspective in the process, and it might be that the middle gound is the way forward. That is not using the fully wide angle and then not having to apply so much correction.

Looking at the before and after images, I'm not sure that there is any difference in the perspective caused by the manipulation, but I'm also wondering if WA lenses also compress perspective like telephoto lenses do, that is, the more you get away from the 'normal' human view, the more the perspective changes. Anyone else found this, or have a view?

[Markulous]

Wouldn't a wide zoom expand the perspective (the reverse of a telephoto zoom)? Since I don't own one, I can't experiment!

I've used PTLens to successfully correct perspective/convergance/distortion - especially as I could write the configuration for my Zenitar 16mm on a Sigma!

[Dabhand16]

Originally Posted by Markulous

Wouldn't a wide zoom expand the perspective (the reverse of a telephoto zoom)?

Good question - don't know!

When you look at landscapes shot with WA lenses that have large FG interest, such as a rock, is the impression of depth in the image distorted? I'm going to look at these images with this in mind in future.

It is commonly known that tele lenses do compress perspective, and the images perhaps make it more obvious, but I've not really consciously looked at this aspect of WA images.