How do we convince Kodak to supply an Ektar 100 calibration target to LaserSoft?

<p>Apparently, LaserSoft relies upon an outside supplier for their calibration targets, which are used to create film profiles for SilverFast. But the supplier has no intention of providing a target for Ektar 100. I sent an e-mail to Kodak about this. Any other ideas?</p>

<p>There are no commercial standard targets for color negative film. Ektar is no exception. If you want one for a particular film and lighting situation, make one yourself with an IT8 reflectance standard or an X-Rite Color Checker chart.</p>

<p>Apparently there is something called a target negative. I think such targets are used in the film industry to calibrate the cine scanners. It is not the same as an IT8 target for producing an icc profile. I suspect it is used to provide information about the spectral response of the dyes in the film.</p>

It would be considerably more difficult to calibrate a scanner with an IT8 target for negative film, since the negative's properties such as minimum density and color balance are influenced both by the unexposed film's age and the freshness or capacity of the processing chemicals. Aged film shows an increase in minimum density, which might be aggravated by insufficient bleach-fixing. If fresh chemicals are used only once e. g. in a rotating drum processor, an IT8 target might help.

<p>Heinz....This is not an IT8 target. It is somekind of target used in the film industry to calibrate their scanners when scanning their negative film.</p>

<p>well then give us a link so we know what you're talking about. Are you sure they're not making their own targets by shooting a Macbeth Chart or whatever with each roll of film they put in the camera?</p>

<p>You can make a profile for a negative film for a particular lighting scheme. You'd have to do this every time you change the lighting, so you could conceivably end up with several targets on one roll of film.</p>

<p>One other unique characteristic of color negative film that I haven't seen mentioned much is that the contrast and density changes that occur with changed exposure and lighting scheme are not linear. The orange mask also enters into this; one of its purposes is to enhance contrast for some of the color layers, while also keeping something else in check -- it's pretty complicated and I don't remember all that I read about it.</p>

<p>It makes for a kind of "shifting sands" scenario which makes it pretty much impossible to profile once, then use the profile many times.</p>

<p>You're better off just messing around with the color until it looks right.</p>

<p>While SilverFast depends on an external vendor for the calibration process, I seriously doubt that the vendor has ever been the film suppliers.<br>

What the vendor would need to have is a photometrically well-known calibration target (grey scale and some set of color patches), along with absolutely standardized lighting and exposure. The vendor is basically providing a color sensitometry service.<br>

I do find it hard to believe that providing that is such rocket science that SilverFast can't take it in-house. The totally lackadasical attitude that SilverFast takes to maintaining their C-41 film profiles is a major crock in their NegaFix story. I still like the product, but I find this aspect absolute infuriating. They seem to be arrogant that they must depend on this external vendor.<br>

Also, SilverFast don't make clear what the aims of the NegaFix profile are. When Kodak was doing PhotoCD, they made it clear that the aim was for the scan to look like the scene photographed, to remove the "look" of the film. (There was an option to make the scan look like the film, at least for slides.) SiverFast doesn't make that clear for NegaFix. (Well, at least not in English, maybe in German.)<br>

Similarly, SilverFast doesn't give the customer enough information to generate their own film profiles. Sure, you can edit the curves and save a custom profile. But they don't say whether the axes are linear or logarithmic, they don't say how exposure compensation works, they don't say what the resulting gamma should be, etc. They only provide the "how", not the "why".<br>

Also, I don't think that the vendor provides that high-quality sensitometry, or the film processing isn't consistent, or they take the profiles on different scanners. They are all over the place. Also, since different scanners do respond differently to each film vendor's dye set, the profiles really can only be accurate for one scanner, for any other scanner they will need tuning. But, the lack of clear documentation makes tuning problematic!<br>

At times I feel NegaFix is "too clever by a factor of two".<br>

For 35mm C-41, I'm much happier with Nikon Scan 4.0 on my CoolScan IV. No NegaFix, but negatives just come out right-on in color balance, at least when exposed in daylight. I only use SilverFast Ai on my Epson V750, mostly on B&W medium and large format work.</p>

<p>Interesting points, John. When Googling on this topic, I came across some references to Kodak providing calibration targets for the movie film industry for calibration of their cine scanners. The targets comprise various grey patches, and I believe also some color patches. And yes, such calibration can only be good for one particular scanner, so there would certainly be a less than perfect result when using a profile on one's own Nikon 9000, for example, when the profile was generated on another Nikon 9000 at LaserSoft's headquarters. For now, I have given up on Ektar. I've been shooting Portra 160VC, and am happy with the results. But these sort of things are enough to drive one to digital!</p>

<p>uh, benny, as soon as you throw the scanner in the mix its digital... hate to break it to you, but i often spend a lot of time correcting digital images as well. Not as much per image, usually, but, its still work. If you want color accuracy and to be able to use targets, shoot slide film.</p>

<p>Dan...I meant....drive one to capture with a digital camera.</p>

<p>i know. im saying that a) you;re already in a digital workflow b) you often have the same headaches with digital - despite the fact that with film you sometimes spend a little more time per image, but not always.</p>

<p>Oh, as for how I scanned my Ektar 120, I think I used the Portra 400VC profile in SilverFast Ai. Experiment with all the Portra film profiless, since they all use the same dye set, which Ektar 100 also uses. So you've got that side of the equation consistent.</p><div></div>

<p>John: How do you know it uses the same dye set as the Portra films?</p>

<p>Maybe I'm complaining too much? The next two pics are Ektar, the first using the VC profile, and the second using the Kodak Gold profile. The first is much truer to the actual scene.</p><div></div>

<p>and the other one....</p><div></div>

<p>I have used Silverfast for scanning Ektar in 120, initially trying all the various NegaFix profiles with each image, and usually going with the Portra 160VC. However, I have found I get much better results now simply ignoring all the canned profiles and going to default/standard. Then I open up the Global Color Correction window and move the cursor around until the color balance looks right. It does vary somewhat for each image- you can't just set it and forget it. Nevertheless, I have found that it gives quite pleasing results. For some reason I don't understand, after the scan I find in PP I often wind up pulling the red curve down JUST a smidge (for entertainment I did the same thing on the first image you posted, and to my eye the balance improved noticeably). Next time I scan Ektar I will try doing that within Silverfast and see if that works as well.</p>