CFV100C on Technical Camera

[Alkibiades]

@Ben730
Are all center filters so highly reflective as the Schneider's one and unusable with lights on?
Sounds like a proper nightmare for interior, dusk and night photography when using SK lenses.

How about using third party filters matched to the f-stop reduction and size? Are there any CF brands better in that aspect?

no. the new rodenstock Filters made for the 23hr and 32 hr are different and very expensive. I did never get the fog where when I used schneider CF on the 28xl I got it even when the sky was too bright ( even on cloudy day)

 

[Ben730]

The article you linked contains this notice: "UPDATE: this turned out to be an issue with all mirrorless cameras that have a short flange distance. Please read this post to understand the issue in detail."

The article to which the update links says: "Basically, this has largely to do with the reflective nature of the sensor surface. As light rays enter the lens, they get squeezed into a very small aperture. At this point, each internal reflection in the form of flare is already part of the image. The light rays reach the sensor and immediately bounce back to the rear element of the lens. In essence, each pixel on the sensor that gets hit with the bright source of light reflects some of the light back to the rear element – that’s what creates the grid pattern."

It's a potential issue with any sensor and lens when the rear element of the lens is very close to the surface of the sensor. Bring a lens element close enough to a digital back (or mirrorless camera) of any make in a specific lighting situation and you could encounter this.

Red support writes:
"Note that this is not just a RED camera issue but happens any other digital cameras that have a Low-Pass Filter or other structure in front of the sensor."
Maybe the IQ3 100 and the IQ1 50 do not have those filters/structures in front of the sensor?

I am neither a camera builder nor a physicist.
I saw this color pattern with my Fuji GFX. With P1 backs never and I have often photographed into the sun or directly into an Arri M18 HMI light.

 

[Paul Spinnler]

I also never saw this pattern on a P1 back.

I've shot P1 / Leaf backs exclusively for the last 15 years and have many thousand raws with lenses that are VERY close to the sensor. Never saw this. In fact, the 28XL and 23 HR are quite close to the sensor and this is where I should have seen it if that internal reflection theory was true.

At least for P1 you are safe from this one, at least I'd have yet to see a specific scenario which re-creates this phenomenon.

If this can easily happen on a sunny day on the Fuji with the TS30 this is not ideal ...

 

[FloatingLens]

I think the theory with the PDAF points reflecting back on the lens might not be so wrong...

 

[Ben730]

Possibly, I don't know. Maybe it's also a coincidence that I've only seen this phenomenon with the Fuji GFX so far.
I've never seen it with my Nikon Z7 either, but I usually work with it under different conditions.

 

[f8orbust]

I've used all the main SK wides (28XL, 35XL, 43XL) with and without CFs on a variety of DBs over many years and they have performed superbly.

But, given a certain set of lighting conditions, with a certain DB, on a certain day, with the planets aligning in a certain way () ... could there be issues - almost certainly - but this would apply equally to virtually any lens/CF/DB combination that you can think of.

The danger with these sorts of 'observations' recounted endlessly online is that something that happens only very, very, very rarely, suddenly becomes an 'end of the world' problem ... when it all reality, it simply isn't.

 

[Ben730]

I've used all the main SK wides (28XL, 35XL, 43XL) with and without CFs on a variety of DBs over many years and they have performed superbly.

But, given a certain set of lighting conditions, with a certain DB, on a certain day, with the planets aligning in a certain way () ... could there be issues - almost certainly - but this would apply equally to virtually any lens/CF/DB combination that you can think of.

The danger with these sorts of 'observations' recounted endlessly online is that something that happens only very, very, very rarely, suddenly becomes an 'end of the world' problem ... when it all reality, it simply isn't.

The weakness of the Schneider center filter was a recurring problem for me (and for some other photographers, by the way), so it's not rare at all.
If it hasn't appeared for you, you either have other center filters or a different view of the images.
"Super performance" is, of course, purely a matter of opinion.
I find it absurd to suggest that this problem should not be taken seriously. It's not an observation, it has nothing to do with planets.

A young architectural photographer reading this thread should be aware of the weakness of Schneider CFs
just as he should be informed about all the good aspects of Schneider-Kreuznach lenses and there are many of them.
I would like to show you how I take 10 pictures in a row with the ghosting effect in a normal interior architecture photo assignment.
Fortunately I sold the necessary lenses years ago.
I posted sample pictures in this forum years ago. It was in the comparison thread between 28XL and 28 HR.
This thread no longer exists, unfortunately it was deleted from the forum.

The color pattern error in backlighting, on the other hand, actually occurs rather rarely. This is certainly not a problem that occurs several times a week for a professional photographer who uses technical cameras. This problem only occurs from F11 and smaller. If you use f8 or bust, you won't have this problem anyway.

 

[rdeloe]

I've used all the main SK wides (28XL, 35XL, 43XL) with and without CFs on a variety of DBs over many years and they have performed superbly.

But, given a certain set of lighting conditions, with a certain DB, on a certain day, with the planets aligning in a certain way () ... could there be issues - almost certainly - but this would apply equally to virtually any lens/CF/DB combination that you can think of.

The danger with these sorts of 'observations' recounted endlessly online is that something that happens only very, very, very rarely, suddenly becomes an 'end of the world' problem ... when it all reality, it simply isn't.

I looked at the light falloff chart for the 35 XL. It's quite steep, which explains why a centre filter is recommended. When you used the 35 XL with and without a CF, did you struggle to sort out the "without CF" images?

 

[Paul Spinnler]

- One should be able to control problems with CFs in specific, very difficult or tricky interior shot situations (e.g. flashes, Arri lights) with the use of shades and flags, like it is common also on film sets to optimize contrast and avoid reflections, no?
- I have never had problems with SK CFs outside, I think its overblown

Both the LCC on BSI for SK and SK CF ghosting issues are not really issues IMHO that impact real-world value and useability of SK. In fact, seeing what the Fuji sensor produces in terms of artifacts when shot in direct sunlight – that's concerning.

I just saw a nice set of samples of the 35 XL with even 20mm of shift I think from another member here via Wetransfer ... I think they might be shared at one point to further dive deep into the case of SK glass on BSI and to dispel the notion brought up here that its sooo difficult to work with - its not!

There are two things with SK glass on BSI, assuming you have CF:

1) Work the lenses within spec (e.g. no shift into tiling, just take a few steps back if you can't fill the frame within IC shit limits)
2) Proper exposure and LCC technique (expose to the right, frame average when there's dark areas, hgih DR in the image, shoot LCC smack in the middle with the histogram)

You can even use an Alpa with fixed shift detents and prepare LCC presets and then shooting SK glass is super easy,