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-   -   Lens Correction (https://www.worldphotographyforum.com/showthread.php?t=3411)

andy153 05-06-08 16:01

Lens Correction Help Please
 
Hi there -
as some may have noticed I am playing around with a Sigma 12-24 mm DG lens - this is the full frame version and it's on a Full Frame camera - so 12-24 IS 12-24. Previously I have been using similar lenses but in DX frame versions so a 12-24 is really an 18-36 where distortion is barely noticeable. I notice that people in the shots so far are quite badly distorted -

Can I ask at what stage of post processing do others correct lens distortion - is it the first thing you do? Also is there any recommended Mac software for this or does the lens correction in Photoshop do the job satisfactorily? Thanks - Andy

Adey Baker 05-06-08 20:05

Is it distortion, though?? As the focal length is about 1/4 of a 'standard' lens you need to view it at a 1/4 your 'normal' distance. Stick your face close to the screen and, hey presto, the distortion should disappear!

miketoll 05-06-08 21:19

A couple of beers might help too! No experience but I would have thought correct the distortion first otherwise you can't even crop to fit your desired size.

jamieZ740 06-06-08 08:47

aah, just leave it, its one of the joys of a wide angle!

http://www.worldphotographyforum.com...00&ppuser=1465

yelvertoft 06-06-08 09:29

Am I missing something here? Having played a bit with the lens correction tool, the "corrected" image has some serious warping applied. To end up with a square/rectangular image, the very curved sides have to be removed. The resulting image is then so cut down that you may as well have used a longer lens that didn't require correction in the first place.

I'm with Jamie on this one.

andy153 06-06-08 11:07

Thanks Duncan - I agree with Jamie and will take his advice - I'm having difficulty adjusting between DX and FX format - if you like - on the D3 the lenses behave as they should - same lens in DX doesn't - you have the magnification factor to take into account. I've now tried a couple of DX lenses on the D3 and get an automatic greyed out part of the viewfinder which crops the sensor to DX format and reduces to 5.1mp. I've got to learn to treat the D3 as I used to treat full frame film cameras.

jamieZ740 06-06-08 11:17

nice one! as Dunc says, may aswell use different lens if distortion is not wanted. and the world was made for a wide angle view
J


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