eliminating cyan corners

[gtmerideth]

snowing again in denver, so to entertain myself i shot my 21 at the wonderful white
landscape. wonderful because if the cyan is going to show up it's now. shot without an IR filter.

as you can see there is quite a bit of cyan. so i embarked on how to eliminate it in post.
after a good amount of entertainment i found the the replace color command worked effectively and without much effort. i'm not the greatest ps wiz but this gives me a way to fix stuff until the solms folks arrive at a solution. the cyan was present witha and without an IR filter. worse with the filter. when you get to the replace command, select the cyan color and desaturate until it's removed. with my CV 15, i had to runthe command twice to get the range on cyans removed. now i'm sure that if the subject is cyan it may suffer. neither lens is coded.
g.

[MP3]

Dear Gary

Great wide angle snow shot. So you mean there are cyan corners even you don't put on 486 IR Cut filters?

Best Matthew

[scott kirkpatrick]

I assume you've got an Elmarit 21/2.8. Code it with a sharpie marker following the instructions on this site and see if that doesn't remove the corners as long as you don't put a filter in front. The 1.06 and 1.09 firmware have a correction for red vignetting coming from the IR filtration at the cover glass over the imager.

scott

[woodyspedden]

Originally Posted by gtmerideth

snowing again in denver, so to entertain myself i shot my 21 at the wonderful white
landscape. wonderful because if the cyan is going to show up it's now. shot without an IR filter.

as you can see there is quite a bit of cyan. so i embarked on how to eliminate it in post.
after a good amount of entertainment i found the the replace color command worked effectively and without much effort. i'm not the greatest ps wiz but this gives me a way to fix stuff until the solms folks arrive at a solution. the cyan was present witha and without an IR filter. worse with the filter. when you get to the replace command, select the cyan color and desaturate until it's removed. with my CV 15, i had to runthe command twice to get the range on cyans removed. now i'm sure that if the subject is cyan it may suffer. neither lens is coded.
g.

Gary

You and I are only 50 miles apart as I live in Fort Collins. I would love to meet with you and share Leica experiences. Give me a call and lets meet and talk and get to know one another. Call my cell at (970) 231-8110).

Best

Woody Spedden

[johnkuo]

I'm also confused why there would be cyan corners when no IR filter is used. Could you elaborate on that?

[scott kirkpatrick]

Originally Posted by johnkuo

I'm also confused why there would be cyan corners when no IR filter is used. Could you elaborate on that?

Simple. There is already an IR filter over the CCD. It's too thin to do the whole job, but it is thick enough that the extra optical path that light sees going through it in the corners at, say, 30 degrees from vertical, causes some loss of reds. Losing red when you start out with a neutral grey or white leaves you with cyan. If you have your lens coded, the existing firmware will remove at least some of this.

scott

[magyarman]

What you got I do not see is cyan corners. What is looks like you did it, take away all blue from skye, make it white. Cyan corners which come after IR filter cant to be fix up in Replace Colour. Why? Becaus is strong in corners and got wicker to central. This I now only one softaware make it easy fix up cyan corners calls Panorama Tools. Inside have Radial Luminance which make fix up more corners oba less to central. I use one time on other foto here who got it real cyan corners, is works very nice. Except 6bit is best one how to fix up.