Vignette trouble - DPChallenge Forums

Canon EF 24-105mm f/4.0L IS

02/27/2012 09:44:05 PM · #1

I have had this problem before and it somehow went away... but it is back and I can not find the thread.

My vignettes look like the rings at the end of the "looney toon" cartoons where porky pig pops out and says "th-th-that's all folks.

Well maybe not that bad, but there are very annoying rings instead of a nice smooth gradient.

I have tried a circular gradient, disort>lens correction, marquee>refine edge>smooth>blur

But it all looks the same. I just calibrated my monitor... Can that be it?

Granted this is heavy, it is just to show you what I mean, and it looks worse with other colors.

Any thoughts? thanks!!

scalvert

Canon EOS-5D Mark III

02/27/2012 10:09:50 PM · #2

Looks OK here. Is your monitor set to 24 bit?

Sony 24-70mm F4 Vario-Tessar T* FE OSS

02/27/2012 10:19:16 PM · #3

This just started happening today.
I did notice that if I apply the same vignette to an existing shot the rings are not there. It only seems to be on BG's that I filled with a solid color. Does that make sense?

Bear_Music

Samsung Galaxy S24 Ultra

02/27/2012 10:20:53 PM · #4

Looks fine here. The problem's on your end, we're not seeing it.

R.

scalvert

Canon EOS-5D Mark III

Canon EF 24-105mm f/4.0L IS

02/27/2012 10:22:38 PM · #5

A gradation on a solid color will often show rings, particularly if the transition is high contrast. That's just the way the pixels work. The best way to solve that is to add noise (2 or 3% should do it).

bhuge

Canon EOS-550D Rebel T2i

Canon EF 50mm f/1.8 II

02/27/2012 10:23:08 PM · #6

It usually depends on the color you pick. Some have a lot more increments then others. I think it's usually the yellow/red/violet areas that have this problem. I think it has something to do with the human eye picking up these color differences better then the other hues.

I don't notice it much with this particular image, but when I do notice it I just add a very very light noise filter (1-2%) and the rings go away.

ETA: looks like I'm too slow :)

Message edited by author 2012-02-27 22:23:56.

02/27/2012 10:24:59 PM · #7

Cool, thanks guys...
Now what the heck happened to my monitor. Maybe I should recalibrate it...again?

02/27/2012 10:26:49 PM · #8

Originally posted by scalvert:

Looks OK here. Is your monitor set to 24 bit?

it is at 32bit. I don't have a 24 bit option only 16 and 32.

bhuge

Canon EOS-550D Rebel T2i

Canon EF 50mm f/1.8 II

02/27/2012 10:42:50 PM · #9

Originally posted by sinistral_leo:

Originally posted by scalvert:
Looks OK here. Is your monitor set to 24 bit?

it is at 32bit. I don't have a 24 bit option only 16 and 32.

In windows 24bit and 32bit are effectively the same thing. Both are 8 bits per channel, but with 32bit they include an alpha channel. It doesn't make any sense why they label it that way.

Unless you have a high end workstation graphics card (such as a Quadro) and a very high end monitor, you can never see anything over 24bit. Even then only a few applications support pushing around images with that color range.