Wideangles magenta shift

[satureyes]

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Me again..

 

So I've JUST got my M - and set it all up with the Voigtlander 12mm 5.6 (latest version) and manually set the camera as a 21 2.8 non asph which is accepted as the one to use for this lens.

 

Worked beautifully on the M-E and M9 with these settings but on the M240 it's hell with purple edges left and right of frame. Even with not setting it as the Leica 21mm it gives bad purple fringing.. the lens setting doesn't seem to make a difference.

 

I am really disappointed now.. I took some killer shots on the other M's with it - and wondering what I can do to improve the purpleness.

 

I'm wondering if a different lens profile is needed now the sensor is different.

 

I also noticed that I can see the purple fringing on Live View - as well as the end photos obviously...

[CaptZoom]

Use the software "Cornerfix".

[satureyes]

I know- but this is an added step and just lifts the corners - however I don't know whether the widely accepted 'code' for the 12mm of 000001 is now no longer the right lens. It's been suggested that the one to use is he Tri-elmar so tomorrow ill try the Tri :-)

[BerndReini]

Maybe someone else can chime in on this, but when I put the M240 through its paces side by side with the M9, I found that there was a lot more fall off at the edges than with the M9 when I left the lenses and settings as uncoded. I wonder if the microlenses on the new sensor are not as effective as the old and stronger in camera correction is required.

[CaptZoom]

I know- but this is an added step and just lifts the corners - however I don't know whether the widely accepted 'code' for the 12mm of 000001 is now no longer the right lens. It's been suggested that the one to use is he Tri-elmar so tomorrow ill try the Tri :-)

 

On another forum, some one's getting better results with using the tri Elmar coding.

[satureyes]

Yeah- I have tried a few different codes manually. They don't seem to make a huge difference than 'uncoded'. This is strange.

 

I got way better results with the M9 and the 12. It could be just the room I'm taking the test shots in- and the mix of lighting but its very obvious even just looking at live view.

[Lindolfi]

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I know- but this is an added step and just lifts the corners

 

No, it also removes discoloration gradients such as italian flag phenomena.

[jaapv]

It is logical. With M8 and M9 Leica used shifted microlenses to correct extreme incidence angles . With the M it uses the shape of the microlenses adn small sensor depth to combat this situation. So it can be expected that the sensor reacts differently to lenses like this one. I think you will just have to deal with it in post processing. If you don't want to use Cornerfix use LCC profiles in C1 or the flat field correction Lightroom and others contain.

[satureyes]

It is logical. With M8 and M9 Leica used shifted microlenses to correct extreme incidence angles . With the M it uses the shape of the microlenses adn small sensor depth to combat this situation. So it can be expected that the sensor reacts differently to lenses like this one. I think you will just have to deal with it in post processing. If you don't want to use Cornerfix use LCC profiles in C1 or the flat field correction Lightroom and others contain.

 

Thanks for that explanation- really helped. I've had people tell me my camera is faulty. Clearly not true.

 

 

So looks like cornerfix will be needed. Just being lazy and looking for something that I can integrate into my Aperture workflow. I wonder if there are plugins?

[Hannes Lummes]

Inferring from my test with several lenses and trying different profiles it seems that the new sensor is pretty much fine to quite wide angle lenses, but after a certain point the color issues get wild. And since Leica's own lenses have ray angles not as steep as some other M-mount lenses we don't have even nearly fitting profiles as with M9 which seemed to require more correction with medium wides. Correct me if this is wrong. I don't have M9 or M8.

[Lindolfi]

Just did some tests with the 12/5.6 CV at various settings (anything shorter than 35 mm) and it mainly influences the vignetting which is the least in the tri-elmar 16 mm setting. But in all cases you get a magenta gradient band at right hand border of the image. So since you have to do postprocessing anyway, you can stick to the 21/2.8 setting if that is what you have applied as a code on the lens.

 

Cornerfix would be an option.

 

To remove the effect, it is also possible to do it in a workflow in PhotoShop by creating an action that uses a white image taken with the lens, placing it in a layer and selecting "divide". This wil take care of the vignetting and the discoloration.

[satureyes]

Inferring from my test with several lenses and trying different profiles it seems that the new sensor is pretty much fine to quite wide angle lenses, but after a certain point the color issues get wild. And since Leica's own lenses have ray angles not as steep as some other M-mount lenses we don't have even nearly fitting profiles as with M9 which seemed to require more correction with medium wides. Correct me if this is wrong. I don't have M9 or M8.

 

Perhaps there is a reason there's no lens wider than 16mm made by Leica ;-)

[Lindolfi]

Perhaps there is a reason there's no lens wider than 16mm made by Leica ;-)

 

In this case it may have been the other way around: They may have designed the M (typ 240) with the 16 mm as the extreme end to correct well.

[viramati]

I too find the 12mm works better on the M9 though I have made a preset in Lr4 to deal with the edge problems for the M9 so will try to modify it for the M. maybe more experimentation with the manual lens code settings is needed. My WATE behaves very well on the 240

[AlanJW]

I too have the CV12. It is not 6 bit coded but I have manually entered it as 21 /f2.8 on my M9, which still requires some post processing. Now with the M(240) I will try the TriElmar setting as suggested above. I expect that will also require more adjustments. This has always been a challenging lens to use.

 

My request is that those who have figured out Photoshop and/or Lightroom ways to address this please post - and maybe the mods can add those to the FAQ sticky.

 

Thanks

[jaapv]

Iirc LR5 has a flat field correction facility.

Caspture One is dead simple. Shoot a frame through a sheet of white paper, upload as an LCC profile and then each correction is one mouse click.

[StephenPatterson]

You can also just batch process all your 12mm images in Cornerfix. As Jaap pointed out there are several solutions, none of which are overly complicated or time consuming, and the results from this outstanding lens are definitely worth the effort.

[satureyes]

Thanks for all this- I really want to have something that integrates tightly with my aperture workflow.

Cornerfix seems the solution for now. I guess I'll have to import my images to Aperture, then mark the ones I need to fix.

I could set cornerfix as the external editor which I have now as photoshop but don't use that much as a stand alone.

 

I wonder if cornerfix can be opened from within Aperture somehow.

[geoff]

I wonder if cornerfix can be opened from within Aperture somehow.

 

A Cornerfix Aperture plug-in would be very helpful.

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[adan]

So I've JUST got my M - and set it all up with the Voigtlander 12mm 5.6 (latest version) and manually set the camera as a 21 2.8 non asph which is accepted as the one to use for this lens.

 

I believe I saw a post earlier this Spring that the M240 corrections supplied for the 21 f/2.8 pre ASPH don't even work all that well with the intended 21 (more purple edge than with the M9).

 

Since the 21 pre-ASPH is my main go-to lens, this is just another reason to happily forego the M240 for the time being. (Even if they were available ).

 

We must hope Leica eventually improves the 21 pre-ASPH corrections through new firmware (as they did for the M9 - after several attempts over 18 months).