Out of Sight. Out of Mind.

Kind of strange, that I would forget a whole album filled to the brim with negatives. Especially the color negative films i had forgotten entirely. Probably because I had simply too much trouble to get good results with scanning - and knew that the smaller 24x36 negatives hold even less quality in combination with a flatbed scanner. So, along the road I forgot about them all.

Out of sight, out of mind kind of style.

It is those that now come to the fore. And that album is really thick with many negatives !!! The results are very lovely, and I have never enjoyed the work so much as I do now. But there is a new problem - which I am not entirely sure where it comes from.

 

Mysterious Inference patterns in color negatives

It is a "diagonal fence pattern" which emerges in my color negatives i scan with a digital camera. First I thought it might be some pattern coming from the back of my camera (Mamiya 6), but then i found this pattern even in other color films... My assumption is that it has something to do with either the electronic shutter of the Canon EOS R camera - or/and the LED light source (Kaiser LED Slimlite Plano 2453) That something affects each other.

I know this pattern is not part of the color negatives - and I have never encountered before (with the older Huion light panel, for example).

I could imagine that the LED's in the light panel create an inference pattern during the exposure. Here i show you an example in exaggerated form (in black & white)

 

 

Almost impossible to correct

This makes images which contain large areas of very even surfaces, like sky and clouds - show off a weird diagonal "fence" pattern - which I can't correct really.

Very annoying. It makes skies with ominous clouds almost impossible to deal with. Blue sky works, but only partially. If I for example change color balance in the blue sky, then this pattern becomes suddenly much more visible.

I will do experiments with the light source (Kaiser LED), with various light levels. As well with the camera shutter; electronic vs mechanical shutter - in order to see I can discern any differences.

I really hope that the new light panel is OK, because the LED's have high color purity (CRI). It would be a shame having to stop using it. Gosh, isn't it funny how new technology can really give you a lot of new headaches ? There is seem to be something more, the deeper you dig, the finer nuances you try chisel out in teh art of a hobby or profession...

There is always something". It is a whiny sentence.. but it often take a bite out of spirit and energy.

Can't say that I am a big fan having to solve this... I aim to fix this somehow, before I can continue with serious color work... *tralalala*

*rolling my eyes*

 

I FOUND THE ERROR

it was the new Kaiser LED panel with it's high (pure) CRI color index - but instead inducing diagonal-fence-or-grid-like patterns in the red and green channel of all digital images (Canon EOS R) made from color film negatives. This disqualifies the Kaiser Implantation LED panel directly for being utterly useless for reproductions.

I am now using my old Huion panel (with unknown CRI color index) - which uses colder light temperatures, but at the same time, I am skipping the physical Cokin Cyan filter, while setting the camera lower to 3300°K (instead of 5300°K). The results: Working perfectly with the Negative Lab Pro software. No more disturbing patterns in the reproduced color negatives !!!

In fact blue colored sky actually turns out better. So whatever the forum members and guy behind Negative Lab Pro wrote about the Kaiser LED light panel being so good - I disagree. The pattern fucks up any image you post-process in Photoshop due to the introduction of that diagonale-grid-like pattern - basically destroying images (in the worst cases).

My first intuition, the suspect cause of what could lie behind - was that it must be the light panel; it's LED's sending out a special pattern interfering. It proved to be exactly that.

Any changes between light levels in the Kaiser LED panel, or changing from electronic to mechanic shutter in the Canon EOS R - made no difference what so ever. The diagonale-fence pattern still remained.

Until i switched LED light panel. It stopped to appear. Notice that this wasn't immediately visible. It was mainly vaguely visible in deep blue skies. Especially when you examined the red and green channel - or when you increase contrast.

Also in large darker clouds, like thunderstorms, you can suddenly see a diffuse "diagonale grid" pattern in images. Very, very disturbing.


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