Tuesday, November 29, 2011

New Scanner/Big Sky Drive-in Theater

Wisconsin Dells, Wisconsin

For almost six years I've been using a Microtek 9800XL tabloid-size scanner for my large format negatives. It has good dynamic range, adequate to deal with my pyro-developed negatives though it had some trouble with crushed highlights from negatives developed in ordinary HQ formulas with enough contrast for Pt/Pd printing. It didn't really have the claimed top resolution of 1600, but had a valid 1200 ppi which is ample if you're scanning 8x10 and 7x17 inch negatives. Not so much if you want to scan medium format film.

A few weeks ago, I found that the horrid weather we've been having had gotten to the scanner—it had a mold attack. A technician at an office supply dealer about an hour from here wasted my time and money making the scanner clean but useless. He screwed up the lenses or mirrors so the scans are all striped with uneven density. Might be OK for scanning documents on white paper, but for scanning large format negatives to make exhibition prints? Toast. I have no confidence that he can improve the situation.

Tabloid size scanners have always been rare, and at this point the only one out there (other than $20K production models) is an Epson with 2400 claimed ppi, at $2500 from B&H. After careful study, I realized that the Epson 700/750 scanners are built in a way that, from a purely physical standpoint, will let you insert a 7x17" negative into the 8x10" transmission scan live area without crimping the neg when you lower the lid. The 750 "Pro" model has better, coated, lenses than the 700, comes with a kit to do "wet scanning," and includes Xrite calibration software with IT8 targets. The claimed resolution is 6400 ppi which could make sense of fluid immersion scanning for 35mm or medium format negatives.

So, it's here. My preliminary use of it exceeds all expectations. First, this is the first scanner I've had (beginning this adventure in 1992) that I don't have to lie to in order to scan B&W negatives. Every scanner I've had before, even if it could do quite well with color transparencies or negatives, was a disaster if you tried to scan a B&W negative as indicated. My impression was that the software people had never seen an actual B&W negative (this is Epson, Polaroid, Minolta, Microtek—I've had scanners by all of them, and SilverFast software had the same problem as it was supplied with the big Mirotek) and thought it was sort of like a color neg with the color stripped away. Of course it's nothing of the sort. A good B&W negative, not to mention one meant for platinum printing, has vastly more dynamic range than a color neg. If the software doesn't understand this, it will clip the hell out of the highlights and shadows. And they all did. So with all these scanners I had to scan as positive, which easily held the negative's dynamic range (color transparencies have even more dynamic range than B&W negatives, so telling the scanner you're scanning a slide lets it handle the density range of the neg), then manipulate the files afterwards in Photoshop.

But not this one. Using the Epson scanning program, I let the software do a prescan as negative with auto-adjust, from the first negative I tested. I nearly fell out of my chair. The prescan looked great! I called up a histogram, and it was nearly a perfect acquisition. No clipping of data at top or bottom, a little bit on the soft and pale side, which is just what you want from a scan. You put a little punch on that with a simple S-curve in Photoshop after you've got the scan. The key thing with a scan is to get everything the machine can pull out of the negative, without bothering to make it "ready to print." This is clearly a vast improvement in the software over my last Epson scanner and its drivers, so I don't know whether it's just the Epson driver that has come up to speed on B&W or whether the included SilverFast software is on board as well. Actually, I don't care because the Epson software appears totally competent to scan b&w negs and I can't stand the SF interface, so I'll just use the Epson software. When I need to scan color I'll have to go full tilt with calibration and testing SilverFast because I found it was wildly superior to the manufacturer's software—for scanning color transparencies—on the big Microtek. This might or might not be true with the 750 Pro.

So, I tried a 7x17 negative from my recent midwest drive-in theater expedition, scanning in two sections. The scanner has a "film guide" that lets you align a negative by contact, rather than visually (and asks whether it should scan at the glass or at the raised film holder level, thank you) and I find that I can run the whole procedure of scanning in two halves, secured by good ol' tape, and then use PSCS5 Photomerge in the mode that leaves the geometry alone but does Align and Blend, in about 15 minutes or so. I hate scanning. But since a large file scan takes at least fifteen minutes, more likely longer, simply to  clean up, this isn't a terrible come-down from the the old 9800, which took about ten minutes to do a scan at similar resolution, and only got 16 inches of my 17-inch negative.

6400 ppi. Not really. It's a hardware supported, rather than interpolated, resolution, but the hardware isn't up to it. Big jaggies and multiple stripes and strong dark light transitions in the 1974 strip of Tri-X negatives I asked it to scan. I almost fell out of my chair again though, when the prescan of the film holder with the strip of 35mm film returned four thumbnails that looked just wonderful, and, when I hit the Scan button, worked away for a quarter of an hour or so and delivered four scans to the hard drive. 

Then there were the jaggies at alledged 6400, so I just threw that stuff out and told it to scan again, no new prescan, at 4800 ppi. These four files are incredibly clean. And 4800 ppi, even with a film holder that cuts off the edges of the negative, delivers a file that's 22 inches wide, larger than any traditional darkroom print I ever made from 35mm. If I want to make the master file from my most significant 35mm work, I just have to learn how to use the fluid-mount gadgets, retaining the black edge if wanted.

4 comments:

Dennis said...

Color transparences have more dynamic range than bw film? Did I read that right? Isn't the standard wisdom, slides are the least dynamic? I'm am simply curious.

Carl said...

Dennis, two different kinds of dynamic range. Slide film has limited ability to hold subject brightness range. Digital capture now does better, and negative film does much better.

But the transparency itself consists of a greater range of density than a good b&w negative. The shadow areas of a well-exposed slide are much darker than the highlight areas of a well exposed negative. That means a scanner has to work harder to encompass the range of the transparency. A b&w negative with a density range of 1.90 or 2.00 has enough contrast to make a palladium print, and too much contrast for normal silver paper. But a transparency can benefit from a scanner with a range of 4.0 as my new Epson claims to have.

As an interesting aside, back in the 1980s when scanning replaced process camera separations for reproduction (magazines, advertising, brochures) film "got slower." The early high end drum scanners could image thin (highlight) areas of a slide better than the process camera had been able to do, but couldn't dig into the shadows as well, so we had to begin to expose Kodachrome or Fujichrome 1/3 to 1/2 of a stop more than we used to. I'm going to be interested to see if the new scanner can dig out lots of range from some of my Kodachrome work from the 70s and 80s that's been carefully kept in dark storage all these years.

My pyro negatives look really thin to the scanner. They have plenty of range for Pt/Pd because the pyro stain is a great UV-blocker, but the scanner only sees visible light, and so the pre-scan histogram uses less than half of the potential 255 levels. Of course the 16-bit grayscale acquire is loaded with information and opens into a lovely full-scale scan when brought into Photoshop. The scanner software actually does an automatic equivalent of a Curves adjustment that's a little too good. Scanning 30 8x10 negatives yesterday (my recent drive-in theater work) I routinely softened the auto-adjusted pre-scan by spreading the endpoints a little. I want a bit of headroom and footroom and will then put a mild S-curve on the file in PS to strengthen the tonality. Trying to get the scan perfect, ready to print, is a mistake. Leaves you no room for corrections, while a 16-bit scan that's a little soft and a little pale is almost infinitely malleable.

Richard Alan Fox said...

I am so glad you bought that scanner, I have much to learn, thank you for sharing.

Dennis said...

Thanks for the explanation! (sp?)