Converting color scans to black and white

[Stew]

I just looked at the West Coast Imaging web site. Their faq deals expressly with this issue and they are pretty categorical in their statements. See http://www.westcoastimaging.com/wci/page/info/FAQ/faqscan.html.

Does anyone know of a lab or service bureau that is in the business of making scans for professional use that takes a different view from West Coast?

Also, is there a qualitative equivalent to West Coast in New York?

[Bruce Watson]

Eric,

West Coast Imaging uses a Tango. What else would you expect them to say? To say anything else is to devalue their investment and make more work for themselves.

I have two problems with the Tango. First, its minimum aperture is 11 microns. This limits the maximum optical resolution (judged from reading a standard resolution test target, like the 1951 Air Force resolution target for example) you can get from the scanner, and this optical resolution is considerably less than what the film can record. That's because film grain averages in the 3 micron to 8 micron range (IIRC, it's been a while since I researched this last) depending on your film and processing. And of course for a given sheet of film, the average grain size (grain clump or dye cloud that is) is just that - an average over a range of sizes. But if your scanner spot size isn't near your film grain size, you are leaving information on the table. That's just physics. No one is going to argue that a Tango has better optical resolution than a 6 micron aperture scanner like a Howtek D4500 or an Optronics ColorGetter. Certainly the 3 micron scanners (the latest from Aztek and ICG) have considerably better optical resolution than the Tango, and match or exceed the capabilities of today's films.

Second, the NewColor/LinoColor software that drives the Tango apparently (I don't have first hand knowledge of this, never having had the opportunity to drive any of the Heidelberg scanners) drives operators to distraction when scanning negatives, since it's not designed for this service. Aztek's DPL software is, and seems to do an excellent job. So does the ColorRight software that drives my ColorGetter. ColorRight automatically detects and deletes the orange mask and inverts the image for me, and does an excellent job of it. There's nothing complicated about it; it's the default operation.

OTOH, the Tango is a tranny workhorse. It's fast and accurate and a good operator can process a lot of trannies during a shift.

As to the graininess issue. Graininess is effected in part by density. A dense area of a film will be more grainy than a less dense area. That puts the grain in the shadows for a tranny, and in the highlights for negatives. No way around that. But grain shouldn't be your primary concern if you are shooting LF film. I can't see any grain in my 10x enlargements from Tri-X (which is considerably more grainy than either Velvia or Reala), and that's a 1.25 x 1.0 meter print. And, more disturbing for me is the lack of grain one can get from blown out highlights of tranny film. It's like a neon pointer that says "I missed the exposure" but that's just how it effects me.

So, what's my reaction? I think WCI and Michael Reichmann are making generalizations, and I disagree with their conclusions. WCI would seem to have money at stake (they are scanning for pay, aren't they?) which is something to keep in mind when you evaluate what they are telling you.

An example of what I'm talking about might help. This is a passion flower. I made this photograph about this time last year in bright mid-day sun. I haven't seen anyone do anything like this with tranny film. I measured 11 stops with my Pentax digital (one degree) spotmeter, let my local lab develop it normally (no pull or push), scanned it to 11x enlargement (a little less than 4000 ppi). The film is 160PortraVC in readyloads.

I expected the film would shoulder off, and color shift the highlights. None of it. This was an easy scan that makes a beautiful print (UltraChromes on Photo Rag). The only things I did in Photoshop were to fine tune my levels, increase the contrast a bit with an over-all curve, and color correct a bit (I don't have a colorimeter, but I'd guess the color temperature was 9000K or higher - on the blue side).

I hope I didn't ramble too much here...

[Wilbur Wong]

Bruce,

In regard to the Passion Flower, which you measured at 11 stops, where did you place your exposure? Last week, when I shot a weathered branch against a granite rock in full sunlight, using Portra 160 VC, I had metered about 6 stops with my Minolta 1 degree digital. I failed to notice that individual flakes of the granite were apparently much higher in value, and even with a one degree spot at a few feet away I probably would have had a difficult time isolating the "specular highlights". I think I had place my exposure about 2 stops below my highest reading.

How much latitude do you expect from this film?

[Eric Leppanen]

Bruce,

Thanks for your explanation! If I understand you correctly, if Jeff wants the technically best solution for generating B&W prints from color film, he should shoot color neg and then scan using a latest generation, high resolution, "neg friendly" drum scanner (one of the brands you mention, and not a Tango). Is this correct? If so, can you recommend a scanning service(s) which uses such a beast?

Isn't it also true, though, that for lower contrast scenes where highlights/shadows fall within the capabilities of transparency film, one will record more image information with transparency film since the film density range better matches the scene? To date, I have been shooting transparency film for lower contrast scenes, and color neg for everything else. If one were shooting for the technical ideal, wouldn't this be the way to go?

Also, my understanding is that one of the key advantages of the Tango is its ability to extract shadow detail (high density range) from transparency film. Since we are shooting large format film, doesn't this characteristic start to become more important than minimum aperture size? These days I am shooting mostly 8x10 chromes (with state-of-the-art lenses: Sironar-S's, SSXL's, etc.) and digitally printing to no bigger than 40x50", so would I see any print resolution advantage using the latest-generation 3 micron scanner versus the Tango?

[Kirk Gittings]

"I expected the film would shoulder off, and color shift the highlights. None of it." I generally place important shadows on ZIV and let the highlights fall where they may even in the SW on a bright sunny day. I then do a slightly flat unclipped scan to give me plenty of detail for manipulation in PS.

I sometimes work with a service bureau for some of my larger injet prints. At the beginning of the relationship they went on and on about how negs don't scan well. So I only gave them trans. to scan. So for the past year I scanned my own negs and supplied the files to them. Last month I finally told them that the scans I supplied were from color negs on my 4990. They were dumbfounded and now want me to show them how to scan negs. They never suspected my scans were from negs.

[Bruce Watson]

Wilbur and Kirk,

I've come to the same conclusion as Kirk. I use a modified zone system, put my important shadow detail on zone III, and let the highlights fall where they will (including specular highlights, if any). All film gets normal development (no N+ or N- development needed). The reason is that the scanner will take the dynamic range of the negative, whatever it turns out to be, and fit it into the numerical range of the scanner. Assuming that I do a good job of setting up the scan, of course.

As to the passion flower image, I put the shadows I wanted to carry detail on zone III, and the white petals in the sun ended up on zone XI (IIRC). There are tones and colors on zone II, and some black (zone I) areas as well. Of the eleven total stops, nine stops carry detail.

Eric,

In the last few years (since I started scanning) I've used negatives (color and B&W) for scenes with wide and narrow SBRs. I studied this a bit a couple of years back trying to figure out if there was anything to gain from using zone system expansion and contraction development. My conclusion was that a scanning workflow doesn't benefit from this. In fact, a scanning work flow seems to benefit rather nicely from lower Dmax images (because graininess is linked to density for one thing). This scene for example, had an SBR of only a few stops. The resulting print almost certainly has a wider range of tones than the negative itself does.

The key is, with a scanning workflow, you can't tell that by looking at the print. With scanning, you don't have to try to match the density range of the film to the dynamic range of the paper which is what the zone system was designed to help us do. With scanning, whatever the density range of the film (assuming the scanner can read through it, of course), you get an exact match to the paper.

What I'm saying in my less-than-articulate way is that I couldn't come up with any reason to use trannies for anything I do. That doesn't mean that they don't have their uses, particularly in the studio and advertising worlds. But for landscape and exterior work in varying lighting conditions, in a scanning workflow, negative films win by virtue of being able to handle the full SBR of the scene.

As to the question of tranny film recording more information because the "film density range better matches the scene." I have to admit I'm not sure what that means. But it doesn't matter. You can find out for yourself for a few bucks. Find a scene that you think will work to tranny's favor, then shoot a sheet of tranny and a sheet of negative. Scan them both, make prints from both, and compare the prints (under the same lighting of course). See what you think. This way you can find out what works for you and not worry about what works for anyone else.

[Danny Burk]

Jeff,

I'll jump in with agreement on the comments re: negative film. Frustrated with the limited range of E6, I've been shooting 4x5 NPS on a regular basis since last year. The results continue to amaze me; I can obtain a full range of detail in situations that I'd simply have walked past with chrome film. I've done tests shooting a mixed scene including bright white painted wood in full sun next to foliage in shadow; NPS retains full detail at both ends of the scale. Like Bruce, I place important shadow detail on Zone III and let highlights fall where they may.

I concur with the thoughts that service bureau advice and general "knowledge" preferring chrome film is slanted toward the bias of art directors and scanner operators who aren't accustomed to handling neg film. Depending on the situation; I shoot both: it can't be argued that chrome is a bit less grainy, so I shoot it when conditions allow. NPS, however, gives me beautiful scans and prints with a full range of tonality when chrome use would be impossible. I drum scan color neg on a regular basis for my own use and for my scanning customers, and I think you'd be pleasantly surprised if you give it a try.

Regards,
Danny www.dannyburk.com

[bob carnie]

Not to be a smart ass here,
But why would one not capture digitally rather than scan neg or pos?
My test have shown me that phase capture to print is much sharper and better rendition of tones and contrast than any scan, Tango, Crossfield or Imagon.
I look at a scan much like the days of internegs , second generation with loss of quality, do not others find the same results?

[Kirk Gittings]

Bob,
There have been inumerable threads related to your question recently on this forum. For many of us digital capture is simply not what we need yet, because of expense, of speed (with scanner backs), archivability of files vs. film etc. the list goes on and on. We are shooting film and scanning it right now because it suits are needs now. Lets not clutter up yet another thread with this capture vs. film discussion when we are really sharing some important information that has not had alot of play here.

[Henry Ambrose]

Here's the real reason for all that old fashioned "can't scan color negs" talk:

In prior times when you took the transparency to the engraver/seperator/service bureau/printer/pre-press house. (pick what your's was called) they wanted a chrome because they could match their repro to your original. They could accomodate your needs and wishes within their closed loop system on a regular and reliable basis. The chrome was a reference point that everyone agreed on as the truth. There were still discussions and changes but the original film ruled. Negs don't work that way as they involve interpretation from the film to scan - an interpretation that was not bendable to a commercial process that included a contract between many parties for accurate reproduction in printing.

Color neg is perfect for a workflow where the photographer shoots the scene and translates that scene into a print with little or no assistance from others. Apple's Colorsync paved the way for the current situation allowing us to maintain color fidelity through the process. Before that it was a jumble of proprietary systems beyond most individual's pocketbooks. And its hard to imagine these days how amazingly difficult it would be to do this without workable color management.

The problem with a scanning back is mostly cost. Why would I buy a $25,000 back when I can buy a $60 box of film and a $400 scanner or some $30 scans? I'd have to shoot a LOT of film to make sense of a back - and while some folks do, most don't shoot near enough.