Thursday January 11 2007 23:27
I've used the Canon TS-E 24mm L for a while and I came across a couple of things which google suggests others may not be aware of. Here they are..
1 chromatic aberration and lens shift
The 24mm TS-E is an "L" lens and it's not bad at all. It does have some CA however, like all the other wide Canon lenses I've ever seen.
At least it does if you're using a decent full-frame digital sensor and you look closely.
The problem
If you try to fix TS-E CA in the standard manner, which is with the raw convertor, you'll rapidly realize that whilst this works for un-shifted images, for it doesn't
for shifted ones. Specifically you can correct the CA in any one place quite effectively, but because the lens is shifted, the assumption that the CA varies radially
doesn't hold, so you have a variation across the image which Photoshop's raw converter doesn't know about and hence can't handle.
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