Pink vignetting

[BlackPaint]

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This photo has been dramatically edited to show that there is a pink vignetting on the edges of the photos when I edit them.  The pink color isn't there before I increase the saturation, but afterwards it appears in one section.  What causes this?  I can still return the camera if it's a problem.  Thanks 

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Edited July 22, 2020 by BlackPaint

[Ecar]

I don't think it's the camera. Some wide angle lenses may produce purple edges depending on the angle at which light hits the sensor. What lens did you use here?

[Guest]

At Leica, pink (magenta) is often completely normal.

That's why so many SW shoot. 😉

Edited July 22, 2020 by Guest

[Guest]

vor 13 Minuten schrieb Ecar:

What lens did you use here?

show the EXIF:

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[tom.w.bn]

vor 14 Minuten schrieb LEYVA:

show the EXIF:

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This image does not look like a 50mm image. When you manually set the 50mm profile in the camera, that does not change, even when you change the lens.

Edited July 22, 2020 by tom.w.bn

[jaapv]

Use an IR cut filter. All M cameras are IR sensitive. And one can even see it on 50 mm lenses.

[BlackPaint]

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It's a 21mm  super Elmar.  I changed the lens manually for another screw mount 50mm with an adapter that the camera didn't recognize and I didn't know I had to change it back.  

Edited July 22, 2020 by BlackPaint

[Ecar]

As long as it's recognized properly by the camera, the 21 SEM should be fine on the edges, except perhaps in particular lighting conditions. In which case you can either use an IR cut filter, as suggested by Jaap, or get rid of the color cast through flat-field correction (or sometimes even just the gradient tool) in LR.

[BlackPaint]

So the color cast could have come because the camera didn't recognize the lens?   It would be good to be able to use it to an advantage if this is the case.  

[Ecar]

1 hour ago, BlackPaint said:

So the color cast could have come because the camera didn't recognize the lens? 

Well, it didn't "come" - rather, it was not removed... But essentially yes, to some extent. Bear in mind that the camera has no way of knowing what aperture was actually used, so it applies an "average" correction. Also, the effect of the correction provided by the 6-bit coding is very subtle for lenses which focal length is 50mm and above, but quite significant for wider ones.

1 hour ago, BlackPaint said:

It would be good to be able to use it to an advantage if this is the case.  

How so?

[adan]

It amazes me that 11 years after the introduction of the M9, there is still so much confusion about why compact wide-angle rangefinder lenses produce magenta vignetting on digital Leica Ms.

It has nothing to do with infrared light or infrared filters. It also has little to do with the exact aperture used, although a reasonable estimate of the aperture used (which all Leica M digitals can achieve) helps fine-tune the correction of these effects.

This magenta stain is caused by a physical/optical interaction between the microstructure of digital sensors, and such compact wides and superwides that sit close to the image sensor.

The light from the lens, at the extremes of view (the edges) hits the sensor at a shallow angle. This produces leakage and cross-talk between, for example, a green-filtered pixel and a red-recording pixel next to it. Too much light gets recorded as "red" even if it is not red, adding red to the picture edge.

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The Leica M digitals are programmed to fix this inherent physics problem with a localized color correction - if the camera "knows" exactly which lens is mounted (optical design as well as focal length). This is the primary reason for Leica adding 6-bit coding to lenses since 2006 (getting EXIF data is just a nice by-product).

Leica has also improved (but not perfected) their sensors, over the 11 years of the M9/M(240)/M10, to reduce - but not eliminate - the problem. The wider the lens, the more the camera still must know which exact lens is in use, to add software corrections in addition. And there are a few older legacy film-era lenses (e.g. 21mm Super-Angulon f/3.4 from before 1980, or some Voigtlander 21mm (or wider) lenses) which cause such extreme color vignetting problems that they are simply not supported at all for use on color digital Ms (but work fairly well on the B&W Monochrom cameras).

A key point here - every different 21mm lens type, from Leica or other maker, will produce a different magenta stain. A 21 Super-Elmar does not equal a 21 Super-Angulon, does not equal a 21 Summilux, does not equal a 21 Elmarit-M, does not equal a 21mm Zeiss Biogon ZM, does not equal a 21mm Voigtlander Color-Skopar. The optics are all different, and thus the magenta staining patterns and amount will be different. One size does not fit all.

The real question here is why a 21 Super-Elmar was identified incorrectly, since all 21 Super-Elmars come with factory-installed coding.

Which could be that 1) the camera's lens detection was switched off, or 2) the lens's 6-bit coding marks are dirty or damaged, or 3) the camera's 6-bit detector (dark glass window on the lens mount) is dirty of damaged.

 

[evikne]

7 hours ago, BlackPaint said:

This photo has been dramatically edited to show that there is a pink vignetting on the edges of the photos when I edit them.  The pink color isn't there before I increase the saturation, but afterwards it appears in one section.  What causes this?  I can still return the camera if it's a problem.  Thanks 

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Anyway – I love the colors in the picture!

[Casey Jefferson]

7 hours ago, jaapv said:

Use an IR cut filter. All M cameras are IR sensitive. And one can even see it on 50 mm lenses.

Ah, looks like this explain why I've been noticing some of my sunny sky images have some kind of purple/pink tint at the edges, and seemingly only in bright sunny sky. They're a lot more subtle than the OP's image but they appear sometimes. 🤔 Not a big deal though.

[Guest]

vor 10 Minuten schrieb Casey Jefferson:

Not a big deal though.

but unnecessary, who loves magenta or pink

[Herr Barnack]

It doesn't sound like there's something wrong with your camera.  Here are some suggestions -

1:  When shooting with your 21 Super Elmar, make certain that Lens Detection is set to auto on your camera body.  If you are using a non-coded lens, you have to set lens detection to manual and manually scroll through the menu, then select the lens you are using.  When you switch back to a coded lens, be sure to reset lens detection to auto.  According to Leica NJ tech, lens detection's main function is to accurately add the lens info. to your EXIF data but having lens detection set correctly can't hurt.

2:  Make certain you have the white balance set correctly on your camera.

3:  If you are processing using Lightroom, make sure that you are using the Lens Corrections tools found in the right sidebar.  Check remove chromatic aberration and enable profile corrections. 

4:  In Lightroom, you can change the white balance; try different white balance settings to see if a setting other than "as shot" produces a more accurate color balance.

5:  You can also desaturate the red and purple color bands a bit if need be.

Hope this will help.

 

Edited July 22, 2020 by Herr Barnack

[jaapv]

2 hours ago, adan said:

It amazes me that 11 years after the introduction of the M9, there is still so much confusion about why compact wide-angle rangefinder lenses produce magenta vignetting on digital Leica Ms.

It has nothing to do with infrared light or infrared filters. It also has little to do with the exact aperture used, although a reasonable estimate of the aperture used (which all Leica M digitals can achieve) helps fine-tune the correction of these effects.

This magenta stain is caused by a physical/optical interaction between the microstructure of digital sensors, and such compact wides and superwides that sit close to the image sensor.

The light from the lens, at the extremes of view (the edges) hits the sensor at a shallow angle. This produces leakage and cross-talk between, for example, a green-filtered pixel and a red-recording pixel next to it. Too much light gets recorded as "red" even if it is not red, adding red to the picture edge.

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

The Leica M digitals are programmed to fix this inherent physics problem with a localized color correction - if the camera "knows" exactly which lens is mounted (optical design as well as focal length). This is the primary reason for Leica adding 6-bit coding to lenses since 2006 (getting EXIF data is just a nice by-product).

Leica has also improved (but not perfected) their sensors, over the 11 years of the M9/M(240)/M10, to reduce - but not eliminate - the problem. The wider the lens, the more the camera still must know which exact lens is in use, to add software corrections in addition. And there are a few older legacy film-era lenses (e.g. 21mm Super-Angulon f/3.4 from before 1980, or some Voigtlander 21mm (or wider) lenses) which cause such extreme color vignetting problems that they are simply not supported at all for use on color digital Ms (but work fairly well on the B&W Monochrom cameras).

A key point here - every different 21mm lens type, from Leica or other maker, will produce a different magenta stain. A 21 Super-Elmar does not equal a 21 Super-Angulon, does not equal a 21 Summilux, does not equal a 21 Elmarit-M, does not equal a 21mm Zeiss Biogon ZM, does not equal a 21mm Voigtlander Color-Skopar. The optics are all different, and thus the magenta staining patterns and amount will be different. One size does not fit all.

The real question here is why a 21 Super-Elmar was identified incorrectly, since all 21 Super-Elmars come with factory-installed coding.

Which could be that 1) the camera's lens detection was switched off, or 2) the lens's 6-bit coding marks are dirty or damaged, or 3) the camera's 6-bit detector (dark glass window on the lens mount) is dirty of damaged.

 

On second look, I must agree that this is probably Italian Flag, which is indeed caused by crosstalk on pixel (sensel) level. That does not take away that the IR sensitivity of all M cameras is a given and causes colour vignetting and colour shift effects. Try shooting the M240 in noonday tropical sun: you'll get a near-uncorrectable yellow/orange cast.

[BlackPaint]

1 hour ago, Herr Barnack said:

3:  If you are processing using Lightroom, make sure that you are using the Lens Corrections tools found in the right sidebar.  Check remove chromatic aberration and enable profile corrections. 

 

My LR doesn't have any Leica lenses.  Im using the latest version of CC,

[BlackPaint]

2 hours ago, evikne said:

Anyway – I love the colors in the picture!

Thank you, if you're serious.  I know someone thought this was funny, but I happen to like it too.   It's not far off from my original edit.  Just getting used to using these new tools. The ISO is the weak point of the M240, so I'm tying to figure out if it will work for me.

Edited July 22, 2020 by BlackPaint

[evikne]

1 hour ago, BlackPaint said:

Thank you, if you're serious.  I know someone thought this was funny, but I happen to like it to.   It's not far off from my original edit.  Just getting used to using these new tools. The ISO is the weak point of the M240, so I'm tying to figure out if it will work for me.

I am serious. But I didn't mean that I liked the pink vignetting in particular (although it isn't very bad either, and in some way it even adds something to the picture).

But I also meant that it didn't prevent me from seeing the very nice colors in the rest of the picture – especially the neon lights, the sky and the road. 

Edited July 22, 2020 by evikne

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Hallo,

Look here: Leica M

[BlackPaint]

9 hours ago, Ecar said:

How so?

Thinking I could use it to add some cool tones to a sunset or maybe enhance a vignette.