Re: Best tutorial for color negative scanning
Quote:
Originally Posted by
Peter De Smidt
Right. There's no IT8 calibration for negatives.
Yes. The problem is that the density range of positives falls in a sufficiently narrow range that a single test target can be used to give you more or less a satisfactory calibration. Tranny film has to work this way; its original design purpose was for the tranny to be projected (remember all those slide projectors with the round trays?). That's not going to work well unless the resulting film after processing has a convincing black and something close to a convincing white. No one wants to see gray mush projected on a screen.
Color negative film on the other hand typically gives you a huge range of densities. I've got a few sheets that show less than one stop between the most dense and the least dense. First time I scanned one I "stretched it out" without thinking about it too much and was shocked to see it in photoshop -- contrast city!
As you can imagine, something that can vary from a density range of, say, 0.3 all the way to, say, 3.6 is going to be impossible to calibrate. It makes you ask the question -- what exactly am I trying to calibrate?
And I'm not even getting into color. That just makes even more complex. So... no calibration for color negative scanning.
Re: Best tutorial for color negative scanning
Quote:
Originally Posted by
Bruce Watson
Color negative film is a different beast from B&W negative and color positive. The latter two respond well to setting the density range for the entire film (that is, finding the overall black and white points), and scanning for everything that's between them.
Color negative film doesn't really like that. It wants the three colors to be treated separately. That is, each "layer" gets a separate black and white point from the other layers. This is impossible to do with most non-drum scanners...
Not sure I fully get this. Apologies if I butcher this as it's been a while since I last played with it and I don't have SilverFast open at the moment - it won't boot unless it sees the scanner turned on - but my recollection is that in the NegaFix widget I can reset the clipping points for each channel separately and at both ends, outside the range of histogram "bins" that have non-zero counts, so as to retain full information. This works fine for B&W with its single channel, but leaves me with an unbalanced color scan that's difficult to correct without vastly time-consuming meandering around the huge space of possible combinations of adjustments on the three channels.
I suspect I'm missing, or misunderstanding, something important, either about what the scanner and software are doing, about how to systematically and efficiently find my way through the correction space, or both.
Re: Best tutorial for color negative scanning
I like Alex Burke's guide to scanning negatives on an Epson V700:
http://www.alexburkephoto.com/blog/2...-negative-film
Re: Best tutorial for color negative scanning
Oren,
I don't use Silverfast, but you might try the following: Do your normal setting of the end points for the channel with the widest range. Now adjust the other channels by the same amount instead of setting the end points of those channels to just before clipping.
Re: Best tutorial for color negative scanning
Quote:
Originally Posted by
Peter De Smidt
Oren,
I don't use Silverfast, but you might try the following: Do your normal setting of the end points for the channel with the widest range. Now adjust the other channels by the same amount instead of setting the end points of those channels to just before clipping.
Thanks, Peter. I've generally been leaving more room on both ends of all channels rather than setting any of them just before clipping - will try as you suggest and see what that does.
Re: Best tutorial for color negative scanning
Quote:
Originally Posted by
Peter De Smidt
Oren,
I don't use Silverfast, but you might try the following: Do your normal setting of the end points for the channel with the widest range. Now adjust the other channels by the same amount instead of setting the end points of those channels to just before clipping.
This is a good method to get close.
Re: Best tutorial for color negative scanning
Quote:
Originally Posted by
Bruce Watson
you need a scanner and software that's negative friendly. It's out there, but you have to look for it.
care to elaborate?
Re: Best tutorial for color negative scanning
Re: Best tutorial for color negative scanning
Quote:
Originally Posted by
devb
Wow, that actually answers the question the OP raised above. Thanks. I just had a quick skim read, but I will give his tutorial a try the next time I scan some negative film
Cheers
Re: Best tutorial for color negative scanning
Having scanned color negs with a variety of hardware and software combinations, I can say without hesitation that they both make a huge impact on your final scan quality. And if you're using inferior hardware AND crappy software, well, it's just a big waste of your time.
The absolute best color (and black and white) neg scanning software I've ever used is Trident for the Howtek drum scanners. There is nothing else I've found that comes close, but it's not an intuitive path until and unless you have a complete understanding the digital imaging principles, the most basic of which are how to properly set your highlight and shadow points.
The Alex Burke tutorial is filled with misinformation starting with his settings of using a non color managed gamma 1.8 choice and his final scan is just mediocre in quality. I'd say you'd be worse off following his advice that trying to figure it out on your own.
One of the dirty little secrets of neg scanning is that you actually can use pretty much any good color transparency scanner profile as a point of reference when scanning color negs, assuming, of course, your software will let you use one in neg scanning mode. Since you're always working visually anyway, it's very important to use a well calibrated and profiled monitor and that you scanning software actually uses the monitor profile to display (notice that Alex has this option unchecked). You generally start with an auto ranging command that finds and sets the white and black points to neutral automatically. There is often a clipping control available as well, and you need to be able to override the auto neutral results when you know you want a color cast in the highlights or the shadows.
When you're working on a color neg scan AND you have both a monitor profile and an input profile in the display path, you can then use that input profile as the source for your conversion to your working space and you will have a fully color managed color neg workflow. If your scanning software allows you to convert to working space on the fly you can use that feature. On Trident, that feature is broken, so I always just embed the scanner profile and convert in Photoshop, which is both faster and gives me the option to choose whatever is the most appropriate working space for a particular image.
It took me years to get really good at scanning color negs, and that was with the best hardware and software out there. You need to have patience and really understand all of the control options available in whatever software package you're using. Good luck.