Correcting Camera Distortion

[ShaunDon]

I'm sure everyone here has had to do this in there work, so you're all probably the best bunch to ask. I'm working on a project where the background image had to include two intersecting streets taken from the intersection. Because I cannot afford an $1800 wide-angle lens for my $1500 camera, I had to shoot dozens of images from which to choose the best and composite one shot.

 

The issue is the distortion of the 45mm equivalent lens, which obviously makes it pretty difficult to align objects in Photoshop. I used to use a cheap panorama-stitching program called PhotoVista, and in it's process it would first warp the image based on the lens size you input... I'm trying to find a Photoshop plugin that will perform this same function, however most of the plugins I've found so far have you dial-your-own settings. I need a common adjustment according to the lens, if that's possible, so I can uniformly correct then patch together the images.

 

Thanks!

 

Shaun

[Crazy Homeless Guy]

just as a side note, there are special tripods to shoot panorama shots that have exact degree markings. if the quality of the stitch is a huge issue, you might want to try one. i think they can be picked up for around $150.

[Ernest Burden III]

I wrote about this (again) just this week, I think...

 

LensDoc filter from Andromeda

 

I use this filter to tame barrel distortion and correct perspectives. It does what it says it does.

 

However, if you correct all the pictures and then try to join them all, you may find its even harder than doing so with them as-shot.

 

Photoshop CS comes with a new function to join pano pictures. I have been meaning to try it out, and a few days ago came across some pictures two or three at a time, that I had meant to 'pano' so I tried it. The Photoshop function not only joined the two group perfectly, it did it automaticly--I just told it which two pictures to do, it went wild, and the result was as good as I could have done with an hour of layer work. I gave it zero instructions, it figured it all out. You can also use it manually, but I haven't tried that yet, didn't need to.

 

Once it has joined the pictures, you can use several projection types to change the curvature.

 

I did find that since one of the pictures was brighter than the other it blended them but it was too obvious, so I went back and gamma-balanced the pictures, re-did the process and the result was much better.

 

Give that a try, but it needs CS, the newest Photoshop. If you want to post two of your pictures I or perhapes someone else can try it, if you don't have CS available. You could see what it can do.

[ShaunDon]

No way! I had NO idea that Photoshop CS had that ability. Crikey. It did a pretty sweet job of it too... I'm gonna keep playing with it.

 

I had taken a look at LensDoc as the best plugin option, but I'd had the same fears about their corrected images not aligning either. I'm gonna keep playing with Photoshop -- I'm really encouraged now! Thanks!

 

Shaun

[Videha]

Have a look at this "Panotools" its free very good but a bit complex

http://www.path.unimelb.edu.au/~dersch/barrel/barrel.html