Thoughts about the "cast" of colour negative films.

nukecoke

⚛Yashica
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In Chinese networks of film photographers, when someone posts some scanned images from negative films, people tend to comment about something called "cast", or it can be translated to "shifted colouration", literally.

A typical comment upon images from negative films can be:

"Oh look, your images have a cast (and it's bad): everything looks a bit purple-ish/blue-ish. " Chinese people are honestly mean and they really tell you if you images are craps.

An image with a greenish cast is something many people can tolerate, since it's quite common to get from Fuji Frontier series processing/scanner machine. The Fuji colour theme is the dominating theme and considered to be the "feeling of film". It's uncommon to see the "cast" comment except from the ones who really hate the colour theme from Fuji Frontier...

However there are rarely further comments discussing about what caused the "cast". Sometimes there are wild guesses like: "I think there is something wrong with your chemical/developing/camera or scanner." Well, that's pretty unscientific to say so since usually the OP doesn't give details to tell those variables.

I was thinking, if is there a situation that one can avoid to have the "cast" on one's scanned negatives?

Negatives are not like slides, thanks to the orange-mask we can't compare the film frame in your hand with the scanned ones on the screen to see if there is the "cast". Different scanners have variations of background lighting and settings for RGB channels. Different scanning softwares have different algorithm of orange-mask removal, and you can even define the RGB of the mask yourself. There are too many variables to affect how the images look like in the end.

Moreover, turning auto levels/auto white balance on/off can also give completely different results. They calculated the histograms, and make the gaps gone, make all 256 values fulfilled. Those amazing buttons can even save the images from the errors during developing!

In the end, it's all up to the viewers! Some people may think the colour theme is spot on but the others may think: this is off the target too much! I've learnt a lot from RFF since I picked up a Yashica MG-1 5,6 years ago, and I'd like to see your thoughts about this "cast" question of colour negatives.


If is there a situation that one can avoid to have the "cast" on one's scanned negatives?


If not, then what is a good cast, and what is a bad cast?

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This shot of mine was accused to be too purple-ish :(
 
What matters is if the shot is the way you want it to be.
The pic above is a bit cold (colour temp speaking) but it is also in the shade which does that. It depends on the feeling you are trying to project. A cool day? etc
You can try to make several edits and see which one YOU like best.

I have found that my C41 scans nearly always come out too green (Noritsu) but it is a really easy fix in LR.
 
It isn't Chinese sindrome only. It is colorshift, often due to wrong developing. This is why it is bad. For analog prints.
But most of color shifts are correctable in the LightRoom. I do it all the time :)

Good cast for me is in old Kodakchrome :)
 
I understand what you are saying,
but why would not correct the cast in a secondary program like Lr, or PS, or any other editing software before you show it of?

Personally, I do not use "Auto" scan settings.
I always adjust the RGB channels for color balancing in the scanning software.
And adjust exposure also.
Then into Lr for any other adjustments.

no cast is a good cast.... unless it was photo w/o flash, and artificial lighting (green, or orange mainly).
Even with artificial lighting, many times the correct WB can still achieved, eliminating the cast.

Some scanners allow for profiles for different films, there you can use a color test target to get the right WB. for a film type.
Then you can just open that profile when that film is used.
 
I believe this happens because the scanner software only neutralizes the shadows and highlights and assumes the midtones will fall in line if those are right, the problem is that the colors aren't straight for each color so there will be error in the midtones out of the scanner. I think using portra 400 will solve a lot of this. I have only experienced a red muddy cast with bad processing, I think weak developer. Superia 200 has a green cast, and most lenses have a cast.

I like to take pictures at twilight, so I get a lot of blue pictures, which sometimes I like, sometimes it's too much. Imo, your picture is a little too blue, but I used a grey (midtone) eyedropper in canon's DPP on the sidewalk to get this...just poked around until it looked ok.
 

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In my experience, it is rare to get two people to agree on cast, or intensity of cast with color film. Some people have their own personal bias, based on their own color preferences, the color of the light as filtered through clouds, trees, etc. Experience with using color film may give one a better ability to evaluate color, but those pesky biases will still have an influence.

As mentioned above, if you like a print, that is what is really important.

If you are really serious about getting colors in a print to match what was there (not necessarily what you think you saw) the solution is to use a gray card in a part of the scene you won't include in the final print, or do two exposures, one with the gray card. You will still need a way to measure 18% gray, or calibrated eyeballs, to make the final print.

And even then, there is no guarantee you or anyone else will like the result.
 
Auto color in photoshop will neutralize a color cast 90 percent of the time. The other times correct it in camera raw.
 
I agree you probably can improve the photo by warming it up a bit.

I also agree with the Portra recommendation.

Lastly if you can't make it a better photograph for your desires with the tools you have you may consider "Colorperfect" software. I've had good success with it and use it 100 % for my C41 color scans.


Jim
 
Most of the time it's just poor scanning or editing.

Usually in my experience it's caused when someone tries to compress all of the highlights into the image, which causes a bluish tint.

See attached for a quick fix in PS.
 

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In the prehistoric times, when I still shot colour, I used the Vuescan function of defining "pure gray", which was a sampling of a piece of film that was beyond the frame (not exposed). You then proceeded to scan the whole roll with this "white balance" dialled in.
Having said this, sometimes there is a hue given by the type of film or the lighting itself, and at this point you need to decide if you like it, or not - in which case you can correct it in PS.
On another note - some people love the look of ISO 400 colour negative film exposed at EI 100 or less - try it with the portraits.
 
Generally speaking white should be white in a scene. There should be no "cast". Same with black. It should be a rich, deep black. I remember the agony of trying to balance the colours when printing R4 prints. Dial in your magenta and cyan to a preset and make your first print. Look at the "cast" and see what needs to be adjusted. We had filter sets we could hold over the print to see how much more magenta or cyan to dial in or dial back to get the whites white. Thank god for PS and the easy of playing with sliders.
 
Before I comment on color renditions of others' photos, I always make sure my monitor is somewhat precisely adjusted.

Back to the topic, the easiest way to eliminate the "cast", assuming your scanner has evenly distributed light source, is to select the unexposed part of the roll, lock the film base color. Scan RAW, reverse it in Photoshop, or use the NegFix

Furthermore, use ColorPerfect to adjust different kinds/makes of film accordingly.

That's by far the most accurate way to my knowledge to scan negatives.
 
I agree you probably can improve the photo by warming it up a bit.

I also agree with the Portra recommendation.

Lastly if you can't make it a better photograph for your desires with the tools you have you may consider "Colorperfect" software. I've had good success with it and use it 100 % for my C41 color scans.


Jim

I use this program for all color RAW digital, E-6, C-41. If you hit a gray area with the mouse arrow it will correct 'cast.' I would use the concrete in the foreground for correction on your image.

I also use RAWtherapee (open source) for temperature control. RT also has more color correction tools than you or I could every learn, but I have used a few. One has been helpful with my toughest problem; skin tones.
 

If is there a situation that one can avoid to have the "cast" on one's scanned negatives?


If not, then what is a good cast, and what is a bad cast?

I don't think you can avoid some cast in the base scanned image, and it isn't worth the trouble of spending time eliminating it in the scanning software, just get close. But just hitting the 'Auto' color button in Photoshop improves your image a lot. If you have the Nik Suite of software you can even improve it further automatically by using the 'White Neutraliser' in Color Efex to take a color level from the white paper of the poster. You then have a punchy rich color image rather than one that looks like it has a fog over it. Obviously you can do these corrections longhand with skilled use of the software, I'm just saying it doesn't have to be difficult.

Second point, what is a good or bad color cast? A good color cast is one that reflects the scene accurately or in a way you want the scene rendered. A bad colour cast is one where you know its wrong and don't know what to do to correct it.


V
 

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This is not a new problem.

Negative film (B&W or colour) has always involved interpretation in order to arrive at the final output (scan or optical print). Optical printing involves selecting paper grades, developers, and in the case of colour printing, filtration settings. This is why we did test prints; to determine the optimal settings *for the intended result*.

Likewise, there is nothing at all wrong or abnormal about removing a "cast" in digital post-production.
 
I hear there are people who do not edit their negative scans to keep them untainted, analog (?!?) and vintage. To me this is like grinding green coffee and drinking it as is, to not modify original taste. Negative is a green coffee, one makes it looking and tasting up to his wish. Scanning/editing/printing is like roasting, grinding and brewing. Surprisingly few people brew green coffee, compared to roasted.
 
This is a complex topic as the reprensentation of a photograph derived from a film negative on a computer screen and its perception by the viewer is influenced by many factors, and not in the least by the monitor hardware and its adjustments and your personal color vision.
So indeed what might apper as a warm cast on your monitor might appear as a cold cast or neutral on a different monitor; or even with the same monitor two persons might perceive two different casts.
Development errors (even small ones) WILL cause color shifts, but as others have noted, most of the time this can be corrected at the scanning/post processing stage. When I see a picture posted on the web that was scanned from a film negative and has a pronounced, unintentional and unnatural color cast, than I would guess that in about 90% of the cases the problem is user error during the scan or post processing stage.
 
A precondition is a properly calibrated monitor. Before I began using ColorPerfect, I used the lock film base colour that Marek is describing above. However, that is unnecessary with CP which I find produces very accurate results (and is good because it saves 1-2 previews too). Of course, this can also be done (in various ways) in Photoshop but I like to do it in CP.

Ensuring that whites are actually white is a good baseline, which is why it's called white balance I guess.
 
If the color-cast adds to the image (convey mood, tame highlights, modify "the look") then keep it.
Otherwise try to remove it.

If someone offered "Hey, your picture is too purple" to the ones I like, I'd just say "Thanks for your support, I like it that way"
 
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