CornerFix -- help please

[JHenry]

Hi all,

Been having problems getting adequate results with CornerFix, and now it's time to ask the experts here...

I'm getting extremely grainy results when I run M9 DNGs through CornerFix. While most of the magenta cast is gone, the edges are very grainy, and the de-vignetting is not smooth.

I've created various profiles over the past few weeks, but can't get one that works well. Given what I'm seeing, I think I must be doing something wrong...I doubt many people would consider the results I'm getting as acceptable, and yet I know many speak very highly of CornerFix.

I've attached an example from my most recent attempt, using the VC 15mm f/4.5 Super Wide Heliar:

Original DNG straight from M9:

After running CornerFix:

And, a crop from the middle-left side edge of the above photo:

What I'm seeing is a very light left edge to the post-CF photo, plus the grain I've mentioned. It's near impossible to see in the photos above, but the center of both the pre- and post-CF files is the normal beautiful M9 look; but the post-CF edges are more grainy than Tri-X.

I've created many different profiles: lens detection on/off, different f-stops, overexposing (as recommended by CF) and exposing as metered, subdued and non-direct light, etc. Still can't get anything that I would consider decent enough.

Is there another way to make profiles, or anybody have lessons learned on making good profiles? Anybody have a profile for a VC 15mm they are "proud" of and willing to share? I know the benefit of CF is that the profile is unique to the lens, but I'm willing to try anything at this point.

I love the look, size and perspective of the VC 15mm lens (except the magenta cast), but am starting to think I should switch it out for the ZM 18mm. Not much point in have the 15mm if I can't get files out of it that I'd like to work on. Again, I'm pretty sure I'm the one doing something wrong, as many people have posted great photos from the 15mm using CornerFix.

Thanks for your help.

Jeff

 

[sandymc]

Jeff,

A big part of what CornerFix does is to amplify the corners. For a CV15, that's usually 2-3 stops in the corners. Inevitably, that amplifies noise as well. If the shot was at high ISO, and a bit underexposed, that noise can become noticeable.

So what you're seeing is probably normal, but I can't be completely sure from the JPEGs whether or not anything unusual going. But if you want to send me the original, and your profile, I can take a closer look. Contact details are here: http://sites.google.com/site/cornerfix/contact-us

Sandy

 

[Gabriel M.A.]

I'm guessing you've coded this lens and had the M9 recognize it as a WATE lens, which would in turn apply not only light falloff on the corners but so-called cyan correction. If that is the case, turn off the lens coding reading option in your M9, and then perhaps applying the only correction steps via CornerFix may get rid of this issue.

 

[JHenry]

Thanks for your responses.

Sandy, I'll send you the files. Appreciate your help.

Tom, thanks for the aperture idea; I'll give that a try.

Gabriel, yes, the photos were coded as 16mm WATE. But, I did try both coded and un-coded profiles to see what the difference would be. Actually think the coded profiles were better.

Thanks again. Love the lens, and want to be able to use it for landscapes. I'm confident the problem is user-error.

Jeff

 

[Ronald M]

Photoshop has some nice paint brushes. I have used them to paint in blown areas and the results were wonderful.

Try the median filter with the center masked off using radial gradient. Or a noise filter with same gradient.