Idiot's guide to CornerFix

[sandymc]

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Phil,

 

I'd recommend leaving the lens detection and UV/IR off at all times when you're using a CV15 - there is the possibility of false detection of a coded lens.

 

Sandy

[footnoteblog]

Is it possible someone could just upload CV 15 profiles to start as a baseline, preferably in better controlled (even, metered studio lighting) conditions for people to work with? To start with?

 

Does anyone _not_ use corner fix? If not, how are you shooting? (with filter, lens on+UV/IR?)

 

I'm down one PW, and even then my lights aren't evenly balanced for color… so I would if could, but I can't so I won't…

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[fotoism]

Sandy:

 

Thanks for being so patient with me.

 

The sun has finally come out and I made yet two new profiles using sunlight. Once again I used white stock in front of the lens hood pointing into the sun using maximum aperture and infinity focus. Two sets of profiles and pictures were taken with lens detection ON+UV/IR and OFF, and matching pictures processed accordingly.

 

Using the filter-off profile to process the no filter picture yielded the best result. Correction was nice and did not require any further adjustment.

 

Using the filter-on profile to process the filter-on picture produced better result than before using the overcast profiles, there is still slight over-correction into magenta but less adjustment was needed to bring it to good color.

 

I tried using the profile created with lens detection OFF to process picture taken with the UV/IR filter on the lens. This combination produced a mostly good result over the vast majority of the picture area leaving four very small corners with cyan cast. Once again those are easy to fix, just a few more clicks.

 

By the way, the lens mount on my CV15 is a CV mount which has the cut-out below the lens and it was not coded, so coding may not have played a part in this whole thing. But your recommendation is most like what I will do: set the menu to OFF and leave the filter OFF the lens! That way the CornerFix will become a truly one-click application!

[fotoism]

footnoteblog:

 

I was wondering the same thing: there must be quite a few people using CV15 on their M8s. I would love to hear other peoples' experience, whether it's using CornerFix or coding the lens as WATE ( I suppose ), or nothing at all.

[carlmuck]

Sandy:

...

Using the filter-off profile to process the no filter picture yielded the best result. Correction was nice and did not require any further adjustment.

...

By the way, the lens mount on my CV15 is a CV mount which has the cut-out below the lens and it was not coded, so coding may not have played a part in this whole thing. But your recommendation is most like what I will do: set the menu to OFF and leave the filter OFF the lens! That way the CornerFix will become a truly one-click application!

 

Phil,

 

I think you misunderstand the purpose of CornerFix. CornerFix was built to repair the cyan shift caused by use of IR cut filters on wide-angle lenses on the M8. If you take the filter off the lens, you don't need CornerFix (you certainly can use it to fix vignetting, but that can also be done in PS). Which is what you are doing with the "filter off" profile.

 

You should have the filter on the lens for both creating profiles and taking images you are going to "un-cyan."

 

Your M8 should be set to not do any processing of the images captured (set Lens Detection to OFF guarantees this, but ON should work as well, just DON'T USE "ON + UV/IR")

 

c.

Edited March 18, 2009 by carlmuck

[fotoism]

carlmuck:

 

Your are correct in that I have confused cyan correction and de-vignetting, because they seem to appear at the same time in the picture. Anyways I just ran out and quickly did what you said: menu OFF, filter on the lens, and created another profile. Unfortunately it is beginning to get dark and the sun has gone. In any case, with whatever I created just now I am able to process pictures taken with the filter on the lens with good results. Even the small cyan corners are gone!

 

Thank you so much to all of you. Now you understand why I used the "I" word in the title.

[footnoteblog]

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I couldn't find any CV15 profiles anywhere. Here are mine; hopefully they're of use to someone.

 

The CV15 profiles.

 

Disclaimer: I shot these on a white background under tungsten lights, with a slow shutter speed, handheld @ISO 320. I found (as mentioned) that the "Lens Detection On" setting (not UV+IR) works best. They seem to work though.

[taketwo]

sorry to bring this old thread up but would cornerfix correct my cyan problem?

 

 

[jerrybro]

For CornerFix and those cyan corners on your CV15 pics: Find a lens profile online, open your images in CornerFix, apply the profile, save your pics.