Scanner profiles don't assure accuracy of colour rendition for colour negatives because the film can't really be profiled with icc profiles in the same way positive transparency film/scanner combinations can be.
Mark is correct...E-6 chrome processing tended to be very, very consistent (unless the lab screwed up) so an Ektachrome Q60 was a really good way of profiling the E-6 rendering. C-41 color neg processing tended to be all over the map and stuff varied greatly by film type. Even with the same film type, film processed in one lab would not be at all the same colorimetrically as another lab. That's why you can't really create an ICC profile for scanning negs.
I just wonder if the orange masks vary as well
If I'd process a negative the way Mark describes by subtracting the orange mask of that specific roll of film - would an ICC profile make sense after this step?
maybe a lil crazy...
but couldnt you take a picture of an reflective it8 target with a certain film (shade outdoor whatever you wanna set up) and then have it developed..
scan it.. use a standard negafix curve for the orange mask so you get a positive.. save it without ICC..
THEN create an ICC profile from the target... !
and there goes your ICC workflow...?
scan.. use standard negfix.. assign new ICC profile.. ??
this way you wouldnt have to fine tune the negfix but just use it for the standard mask
maybe a lil crazy...
..............
scan it.. use a standard negafix curve for the orange mask so you get a positive.. save it without ICC..
THEN create an ICC profile from the target... !
As Jeff and I have been trying to explain, there is no such thing as a "standard negafix curve" because "orange masks" are all over the place, varying in hue, saturation and lightness depending on the vendor, type, ISO, batch, processor and processing date. But to begin with don't confuse orange mask detection with colour inversion; these are separate issues; orange mask detection is one part of the operation, then the colours need to be inverted - properly. Also, on the mechanical side of it, your photograph of the IT8 target would need to produce a result dimensioned exactly to what a profile creation application could read correctly. Let's see what Christoph comes up with, but I'd be surprised if it turned out to be a more practical workflow than simply using a (perhaps customized) NegaFix profile in SilverFast.
And the funny thing is:
Totally controlled and calibrated colors aren't necessarily beautiful, maybe not even THE prerequisite to get beautiful color rendition.
Postprocessing skills, a good calibrated monitor and a good eye are most likely much more important ....
Yes, from the artistic perspective this is really true; that said, good artistry still requires control over one's medium and that control starts with reliable methods and techniques, and so much the better if they are also efficient. Not to say that "good art" isn't also created by random walks, but that's not the main point.
well... for what it's worth some of us have been experimenting with various ways to tame color neg results with color management processes, on a film batch basis. I came up with a convoluted approach that results in some of the best color I have ever produced, for one project, from Ektar 120 scans. However it's not anything really workable, and was simply one idea that will be abandoned on the way to better ideas, hopefully.
If we get something workable for humans.. it'll get posted.
In the meantime, I guess dinking with negafix (I too use Silverfast with my Howtek) and a lot of PS work is the way to go...
Tyler
Yup - sounds right. ProPhoto produces saturated reds from both Nikon scanners (5000 and 9000). It also did the same from the Minolta 5400 back in those days. Selecting the scanner profile at the scan stage when you are using Negafix is neither here nor there - doesn't do anything. It's the assignment and conversion you did in Photoshop that counts. Good, glad you got a usable workflow. Do you find the Holmes colour space much better for these scans than just using ARGB(98)?
Adobe RGB drops/clips a lot of colors my scanner can reproduce, so switching to a wider gamut than AdobeRGB for scanning is a no-brainer for me.
My impression is, that the conversion from the scanner input space into the working space in SF8 is simply bugged.
To me it looks as if Prophoto just was assigned and not converted and that the conversion did not work when using Prophoto as working colorspace in SF8.
I don't think the Holmes space is necessarily better than Prophoto.
The advantage of it is the chroma variants.
My impression is, that the conversion from the scanner input space into the working space in SF8 is simply bugged.
To me it looks as if Prophoto just was assigned and not converted and that the conversion did not work when using Prophoto as working colorspace in SF8.
ASSIGNING the scanner colorspace in PS and then CONVERTING to the larger gamut in PS did the trick.
This should also work with Prophoto.
I will call Lasersoft next week and ask them about it.
I mean:
What happens when we profile the scanner?
We put in a target with known XYZ/LAB values and scan it.
We get a profile which connects the numbers coming out of the scanner with the real world colors.
When suddenly after changing the colorspace a number which represents a real world red tone shows an out of bound extreme red something has gone wrong.
Since Prophoto is a wide gamut colorspace which allows these extreme reds, I believe the number which represents a sane red in the measured scanner profile/colorspace and which suddenly represents an extreme color has been wrongly converted or just been assigned.
So - basically I believe its a bug.
A conversion from a colorspace/profile which gives good color to a larger colorspace which contains the original colorspace should never lead to these extreme colors.
I tried all rendering intents, and the reds were always out of bounds - so I believe its a bug.
If it is a bad idea to piggyback on this thread, I will start a new one but I've been struggling with something similar. Came across an old slide copier and have been playing with shooting my negs with my DSLR. It works pretty well but have had no success with making a decent positive image. Is there any way to get something workable from a raw DSLR image of a negative? Can I feed an image into Silverfast without a scanner (seems unlikely, but have never used Silverfast) and then do as you all are doing?
Just a wild guess but:
Maybe the heavy orange tone of the negatives somehow exceeds the gamut your DSLR can capture and you'll get some clipping and thus no good colors.
ColorNeg/ColorPerfect is a PS plugin that may help. I tried a demo version a while ago for scanning negatives as positives, then removing the orange mask and inverting. I didn't work with it much and didn't get good results immediately. Maybe with a little more learning I could have achieved better results. http://www.c-f-systems.com/Plug-ins.html#plugdesc
If it is a bad idea to piggyback on this thread, I will start a new one but I've been struggling with something similar. Came across an old slide copier and have been playing with shooting my negs with my DSLR. It works pretty well but have had no success with making a decent positive image. Is there any way to get something workable from a raw DSLR image of a negative? Can I feed an image into Silverfast without a scanner (seems unlikely, but have never used Silverfast) and then do as you all are doing?
ColorNeg/ColorPerfect is a PS plugin that may help. I tried a demo version a while ago for scanning negatives as positives, then removing the orange mask and inverting. I didn't work with it much and didn't get good results immediately. Maybe with a little more learning I could have achieved better results. http://www.c-f-systems.com/Plug-ins.html#plugdesc
regarding my post.. yes i know there are def. different orange masks (i developed some GDR orwo color negs myself).. and again.. i wont try this method as i totally agree with you that silverfast negfix is prob. all we need.. but im still pretty sure this process will work!
if i want to scan an orwo film.. of course i have to use orwo for the profile!..
but another aspect you guys talk about is the prophoto "thing" with negafix.. actually i have the feeling the whole colormanagement in silverfast doesnt work for negatives!!
i get different colors weather i use adobe s or prophoto.. although i dont assign it but use it in silverfast ist working space!.. thats a bug right?
it should always keep the konstant colors and use the scanners profile or gamut as ICC and then convert to my workin space and not asign..
thats typical to get redish reds.. if you just assign prophoto!
This may be true, but I think I'm not even getting to that point. From this discussion I'm getting that somehow the orange cast be compensated for and then the colors inverted, you all are relying on the Silverfast scanning software to do these steps. I guess my question is can this be done without silverfast. What if you had a simple scanner and software and ended up with just a scan of your negative just as it is, negative and orange, in a tiff (or whatever, in my case it would be a NEF). Is there any way to get from that to a half decent positive image?
Has to be some of the most dense, convoluted and unreadable material on the internet. Why should people subject themselves to this punishment when there are simple and effective alternatives?
Reminds me of what a lot of people say about Silverfast. ;D
Yes, the web site is pretty dense, but actually using ColorNeg/ColorPerfect isn't any more difficult than using Silverfast. It's probably a little easier. As far as I remember, ColorNeg/ColorPerfect uses negative film profiles in a manner similar to Silverfast.
I just had a call to Lasersoft and the guy I was talking to admitted that there is a problem and they are working on fixing it.
He basically said that in the moment it seems so, that the numbers of the file are being kept in AdobeRGB and Prophoto (or sRGB) is just assigned and that the conversion seems not to happen.
This sounds like AdobeRGB would be always the internal colorspace, no matter what you do.
But they are still examining it and he promised to send me a beta version with the fix if they find the bug.
I am not sure what happens when not using an internal colorspace at all in SF8 - if the numbers of the file represent the scanners native RGB (in my case "SF_T(Nikon LS9000)") or AdobeRGB.
I'll check against a target visually as soon as possible to see whats the best solution.
The simple fix in the moment is:
Any positive file created from a neative scan using Negafix requires AdobeRGB as first assigned colorspace. Be it in Silverfast or in PS later.
This is mandatory for now until they have fixed it.
Assigning my scanner colorspace just worked because it doesn't differ too much from AdobeRGB.
It appears applying a high gamma as I did comes close to what happens if the white point has been set properly. .