Vignetting on CV 15/4.5 with Milich filter holder

[wmspa]

I purchased a Milich filter holder for my CV 15/4.5. For some reason, the filter holder causes vignetting in the outer corners. For illustration, see the attached pictures (taken of the rare German blue sky):

- The first is taken without the filter holder and without an IR filter. It illustrates that the lens - without the filter holder - shows no abnormal vignetting.

- The second picture is taken with the filter holder attached, but without an IR filter. It shows that the filter holder causes the vignetting, regardless of whether or not an IR filter is screwed on.

- The third picture is taken with the filter holder attached and an IR filter screwed on. Vignetting has been corrected with CornerFix, which weakens the vignetting effect, but does not eliminate it (which is natural, because this is not the normal vignetting caused by the lens).

- Picture no. 4 shows my M8 with the Milich filter holder attached.

I contacted John Milich on this problem and he confirmed (after looking at picture no. 4) that the filter holder sits right where it should be. He suspects that something is different with my lens and that I shoud check the filter holder with another lens. Unfortunately, I don't have another copy available and the CV 15 is only available on order here.

It is hard to image that my lens is so much wider than "normal" copies. On the other hand, the filter holder has been tested thoroughly, also by several members of this forum, and John confirmed that he has never been made aware of this problem by any other customer. All this looks very strange.

Does anyone have an explanation for this or has anyone experienced the same problem?

Just to help me for my own testing: What are the specifications of your CV 15 Milich filter holders (i.e. the length of the rear "barrel" and the depth of the "groove" where the Milich holder is pushed on the built-in lens shade, in mm)? Should (can?) I test how wide my CV 15 lens actually is and what is a sufficiently precise method for this?

Regards

Wolfgang

[sandymc]

Wolfgang,

Just picking up on the CornerFix correction, how was the profile generated? With the Filter holder and IR filter attached? Have you tried a profile generated with "Multiple Equations" enabled?

Sandy

[geoff]

Wolfgang

I ran into the same vignetting issue upon first using the Milich CV15 filter holder.

I had read that various prototypes of the filter holder were constructed and tested to find the best possible shading protection before introducing vignetting, resulting in very tight design tolerances.

My main need was to have a more effective lens hood that would help reduce the amount of flare I was experiencing in conjunction with the use of my handheld flash. Therefore, my initial use was without a filter attached. As such, I noticed that the filter holder does not sit without some give and wobble as the contact with the lens is at the tip of lens’ own shade petals.

With a filter attached, the Milich holder makes a much more rock-steady connection since it is now the base of the attached filter that touches the lens. No more wobble and, for me at least, no more vignetting and of most significance no more lens flare.


Geoff
myspace.com/geoffotos

[wmspa]

Originally Posted by sandymc

Wolfgang,

Just picking up on the CornerFix correction, how was the profile generated? With the Filter holder and IR filter attached? Have you tried a profile generated with "Multiple Equations" enabled?

Sandy

The profile was generated using the default settings. It does not look perfect yet - there is some reddish cast in the corners. I'm not sure whether this is the result of the "hard" vignetting caused by the filter holder (causing the software to overcorrect) or of my own imperfection. I will try again with the "Multiple Equations" enabled, thanks for the comment. Could this setting further reduce the vignetting?

Wolfgang

[wmspa]

Originally Posted by geoff

Wolfgang

With a filter attached, the Milich holder makes a much more rock-steady connection since it is now the base of the attached filter that touches the lens. No more wobble and, for me at least, no more vignetting and of most significance no more lens flare.


Geoff
MySpace.com - *g e o f f* - 100 - Männlich - PHILADELPHIA, PENNSYLVANIA - www.myspace.com/geoffotos

Geoff, thanks for the tip, I will try again. So far, I couldn't screw the IR filter deeper into the holder to get better results. I tried, but with the IR filter, the holder sticks out even a bit more, although not enough to significantly to increase the vignetting. Any trick to get the filter deeper into the adapter?

Wolfgang

[sandymc]

Originally Posted by wmspa

The profile was generated using the default settings. It does not look perfect yet - there is some reddish cast in the corners. I'm not sure whether this is the result of the "hard" vignetting caused by the filter holder (causing the software to overcorrect) or of my own imperfection. I will try again with the "Multiple Equations" enabled, thanks for the comment. Could this setting further reduce the vignetting?

Wolfgang

Wolfgang,

Yes, the "multiple equations" mode allows CornerFix to deal with vignetting that has a more complex mathematical "shape". Normally not required, but it might help here. Although there's quite a lot of asymmetry in the mechanical vignetting that will be hard to correct, no matter how complex CornerFix's corrections become. The best solution will be to reduce the amount of mechanical vignetting....

Sandy

[woodyspedden]

Originally Posted by wmspa

I purchased a Milich filter holder for my CV 15/4.5. For some reason, the filter holder causes vignetting in the outer corners. For illustration, see the attached pictures (taken of the rare German blue sky):

- The first is taken without the filter holder and without an IR filter. It illustrates that the lens - without the filter holder - shows no abnormal vignetting.

- The second picture is taken with the filter holder attached, but without an IR filter. It shows that the filter holder causes the vignetting, regardless of whether or not an IR filter is screwed on.

- The third picture is taken with the filter holder attached and an IR filter screwed on. Vignetting has been corrected with CornerFix, which weakens the vignetting effect, but does not eliminate it (which is natural, because this is not the normal vignetting caused by the lens).

- Picture no. 4 shows my M8 with the Milich filter holder attached.

I contacted John Milich on this problem and he confirmed (after looking at picture no. 4) that the filter holder sits right where it should be. He suspects that something is different with my lens and that I shoud check the filter holder with another lens. Unfortunately, I don't have another copy available and the CV 15 is only available on order here.

It is hard to image that my lens is so much wider than "normal" copies. On the other hand, the filter holder has been tested thoroughly, also by several members of this forum, and John confirmed that he has never been made aware of this problem by any other customer. All this looks very strange.

Does anyone have an explanation for this or has anyone experienced the same problem?

Just to help me for my own testing: What are the specifications of your CV 15 Milich filter holders (i.e. the length of the rear "barrel" and the depth of the "groove" where the Milich holder is pushed on the built-in lens shade, in mm)? Should (can?) I test how wide my CV 15 lens actually is and what is a sufficiently precise method for this?

Regards

Wolfgang

Make sure you have threaded the filter into the rear of the adapter. If you screw it into the front you will definitely have vignetting.

[HetDraakje]

Originally Posted by woodyspedden

Make sure you have threaded the filter into the rear of the adapter. If you screw it into the front you will definitely have vignetting.

Picture 2 was without any filter....

Boen

[Etruscello]

The red-ish corner(s) in picture #3 can be eliminated by setting the WATE menu for CV15 to 21mm rather than 16mm. For some reason, 16mm overcorrects. 21mm is near perfect outdoors, 18mm is better indoors under tungsten light. Tom

[wmspa]

Originally Posted by Etruscello

The red-ish corner(s) in picture #3 can be eliminated by setting the WATE menu for CV15 to 21mm rather than 16mm. For some reason, 16mm overcorrects. 21mm is near perfect outdoors, 18mm is better indoors under tungsten light. Tom

The correction indeed needs to be improved. However, I correct the cyan vignetting the software application CornerFix, rather than using a coded lens/adapter and the built-in camera correction. I guess the over-correction was the result of the strong corner vignetting caused by the filter holder.

Wolfgang

[wmspa]

I tried again, having in mind Geoff's comment, both with a Leica filter and a Heliopan filter. With the Heliopan filter, the adapter cannot be fully pushed onto the lens shade, because this filter is a bit larger than the Leica filter. The vignetting was about the same as when I used the adapter without any IR filter - although logically it should be stronger. With the Leica filter, the position of the adapter was identical to that when the adapter is used without filter - and the vignetting was almost gone. There was just some tiny vignetting left in the corners, which an improved CornerFix profile should be able to deal with.

So the essence seems to be that the Milich adapter works fine as long as a Leica IR filter (or another IR filter of the same size) is used, but may cause vignetting if used "stand alone" (strange!) or with Heliopan filters. Maybe also some slight variations in the CV 15's focal length may cause a difference.

If someone has an explanation why there is less (or no vignetting) when an IR filter is used ... should be interesting news. Unlike Geoff thought, it's not the wobbling when no IR filter is mounted, because the vignetting was apparent in all four corners, not just in one or two corners as one would expect when the holder is not sitting straight on the lens.

Thanks for your help!

Wolfgang

[photolandscape]

I have the Milich filter holder and have used it extensively over the past 6-8 weeks.

I too have had problems with vignetting. I have a B+W IR filter tightly screwed into place in the holder. Still, the filter holder/lenshade has a tendency to get knocked around as I am shooting. The nylon set screw is ok, but really doesn't hold it firmly in position. So, I check my images often on my LCD and make sure that the filter holder is snugly pushed back as far as possible at all times. I wish Jim Milich could come up with a fix for the problem.

[Olof]

Could anybody post a picture from these Milich filter holder ? I really would like to see how it looks.

[eric_bowles]

I also have the CV15 filter adapter and see some slight vignetting when the adapter is attached (both with and without a Leica IR filter). I've screwed the filter in as deep as I think is possible from the rear end of the adapter. Vignetting is most pronounced when shot wide open and decreases as you stop down, to the point where it's not a concern after f/11.

BTW, what does everybody use for a lens cap? I haven't had success yet finding a 68mm push on cap....

--eric

[sean_reid]

This is interesting to read. I've made many pictures with the Milich adapter on a CV 15 (with a Leica filter) and have seen no mechanical vignetting.

Cheers,

Sean

[sean_reid]

Originally Posted by eric_bowles

I also have the CV15 filter adapter and see some slight vignetting when the adapter is attached (both with and without a Leica IR filter). I've screwed the filter in as deep as I think is possible from the rear end of the adapter. Vignetting is most pronounced when shot wide open and decreases as you stop down, to the point where it's not a concern after f/11.

BTW, what does everybody use for a lens cap? I haven't had success yet finding a 68mm push on cap....

--eric

As I mentioned in my review, Schneider makes a 68 mm cap.

Cheers,

Sean

[etherfarm]

I just got back from a trip to Israel and the Dead Sea and many of the photos I took with the 15 w/ Milich adapter also have vignetting in the extreme corners. Not too big a deal; I wrote it off as me not pushing the hood down all the way or the filter holder getting bumped. I cropped the images but I'm interested to see whether it is, in fact, user error.

[wmspa]

Interesting to hear that others are experiencing this problem, as well.

In the meantime, I tried again - using a Leica filter (mount) and screwing it in as deep as I could. I created a CornerFix profile using the "multiple equations" method, which seems to be better at fixing this type of vignetting. Even after fixing the corners with CornerFix, the vignetting is still there.

Wolfgang

[jlm]

I'll re-evaluate, though prior to this thread there have been no problems reported to me.

[chris_tribble]

Same thing happened to me - some physical vignette on some frames - definitely related to moving the hood out of line... difficult to see how to fix without redesign a there's such a small surface to fix to on the CV... Main thing now is to know that it can be an issue and to pay attention...

Best