M9 color shift for ultrawides

[Alfonso]

Hi! I'm pretty new to rangefinder photography, so far i'm liking it a lot, and i got a zeiss 25mm that has a slight red shift that is almost fixed by choosing the 28mm asph from the menu.

The thing is, i just got a 15mm voigtländer and i was expecting the red shift to be there as with the 25mm, so i choose the WATE @16mm for it, the problem is, the red shift is there but it's on the bottom of the frame, not in the left as i've seen while searching on the forum.

Seeing this i shot a short test with the 25mm uncoded and the red shift is also present on the bottom of the frame. As far as i have read, the color shift should be red in the left of the frame and cyan on the right, but it seems in mine only shows red on the bottom. I'll prepare some sample pics to illustrate this when i get home, but meanwhile, i would really appreciate some help, does anyone have the same behavior? I tried a summicron-c 40mm and in this focal length doesn't seem to show the problem anymore (i don't have anything longer than 40mm yet )

I tried using CornerFix that seems to do wonders for many users but my night samples were not good and it kept suggesting really weird corrections. What's the typical test shot to pass to CornerFix to create a profile for the lenses?

Anyway, any insight on how to deal with this problem would be greatly appreciated. I was thinking to contact leica, but then, i'm not sure what could i tell them if i'm using 3rd party lenses on it, guess they'll just say it's the lenses

Thanks in advance!

 

[jonoslack]

HI There Alphonso
I have had both of those lenses with the M9, your reports sound about right. The right / left colour shift isn't that simple, and varies with different lenses, often spreading over the bottom of the frame as well.

I'm afraid I simply bought some leica lenses, but I'm sure you can get the 15 right using cornerfix (can't help with explanation I'm afraid).

Leica won't be able to help you, but you should be able to get help with cornerfix for the 15.

Sorry not to be more helpful, but what I'm saying is that:
1. what you're seeing is normal
2. cornerfix is your answer with the 15

all the best

 

[D&A]

Hi Alphonso,

One of the things that helped me greatly to reduce or eliminate "red edge" in some lenses I was using at the time (focal lengths ranging from 15 to 21mm in my case) was to manual set the coding for these lenses in the M9 menu for the 21mm f2.8 Pre asph. Its just a theory but the reason this setting worked better at reducing red edge than say the 21mm f2.8 asph setting or possibly other ultra wide angle lens setting (like the actual setting for the lens in use), may be the strength of corner edge correction Leica programed for the 21mm f2.8 pre asph. For some lenses like the cv 15mm, it didn't get rid of red edge but reduced it to the lowest levels I could achieve outside of using cornerfix. In others such as my Zeiss 18mm, it eliminated completely.

Some have also suggested that in a given lens, sample to sample variation may show some differences in regards to red edge as well as slight differences between different M9 bodies, although less variation with regards to M9's vs. individual lens samples. I guess its psosible if one happens to get a lens sample thats more susceptable to red edge combined with a M9 body that does the same (slightly), the problem is accentuated. Conversly, a lens sample that shows less red edge (due to good optical centering of elements?) combined with a M9 that has less propensity to show it, leaves one with less to deal with. Again this is what some have suggested and why some with the exact same lens may have more or less or the issue to begin with (with their M9).

Hope by manually setting the M9 menu for the 21mm f2.8 pre asph lens setting helps to some degree.

Dave (D&A)

 

[jonoslack]

Hope by manually setting the M9 menu for the 21mm f2.8 pre asph lens setting helps to some degree.

Dave (D&A)

You could also try the 28 f2.8 elmarit asph -- which has very powerful correction.

 

[sandymc]

What's the typical test shot to pass to CornerFix to create a profile for the lenses?

You need a shot of a white wall, or a gray test card - something that's uniformly lit.

Sandy

 

[Alfonso]

Thank you for all the suggestions, i'll try them slowly once i get a day with enough light :-( Days are too short here this time of the year...
Cheers!

 

[wilsonlaidlaw]

Alphonso,

Have a look at this thread;
www.l-camera-forum.com/leica-forum/leica-m9-forum/153831-m9-red-edge-redux-part-ii.html

There is a lot of information on it. We are hoping for a firmware upgrade but this probably and sadly, not forthcoming until next year spring. I have virtually given up using the Wide Angle Tri-Elmar on my M9 because of red edges and asymmetric vignetting.

Wilson