Imacon Flextight : odi et amo
Odi et amo. Quare id faciam fortasse requiris — nescio, sed fieri sentio et excrucior!
The Imacon/Hasselblad Flextight series of scanners is a testament to the power of patents. Each is devilishly simple: negatives get sandwiched between a 400-series stainless sheet and a flexible magnetic sheet, bent around two big wheels, and run between a fluorescent tube at the bottom and a lens assembly and 3-line sensor CCD pointing down from the top. This is true of the cheapest Photo all the way up to the 949.
The variations in Flextights come in the larger models (not the Photo or 343). These have a zoom assembly on the lens that redeploys the CCD pixels to a smaller film width to give 5,700 dpi or more on 35mm film. Almost all Flextights, though, max out at 3200 dpi for 60mm-wide 120 and 220 film, as well as double strips of 35mm.
This article will address the operational differences between a model 343 and a Nikon Coolscan medium-format scanner. The 343 is the only reasonably affordable model that interfaces to FireWire and modern computer operating systems. Some aspects of the 343’s operation are the same as on the X5, the $25,000 champion.
Negative holders. The first fundamental difference between a Flextight and a Nikon is the design of the negative holders. Nikon’s FH-869 carrier uses clamp-down strips to grab the edges of the film and then uses a thumb-operated tightener to tension the film flat. This works most of the time, though it can be tricky to load. The Nikon carriers physically max out at a 6×18 strip, meaning that unless you want a crease in the middle of a frame, you can have a maximum of 3 6×6 frame, 2 6×9 frames, or 4 6×4.5 frames. The alternative (and extremely expensive) FH-869G glass holder sandwiches film between two sheets of glass. Because it does not need to grip the edges of the film, you can scan the entire width of the film. It is not as rough with the 6×18 limit, but it’s still a little risky.
The Flextight holders, by contrast, use magnetic pressure to hold the edges and then bend the entire assembly around a curve to totally flatten the negative at the one spot it is being scanned by the line CCD. Flextight holders generally do not have issues with super-long filmstrips because the ends don’t crunch up against anything (they do hang out of the carrier and/or scanner). Flextight holders, though, because they work best with support on all four sides of the film, are much more format-specific than Nikon holders are. Flextight holders don’t use glass, which also eliminates a dust surface. That said, you cannot get the full width of the film (with all the edge printing) on a Flextight because there would be nothing holding the film.
For most purposes, the Flextight is an easier choice for loading, though not cheap when you have more than the stock holders. The Nikon, though, excels for randomly sized bits of film and anything that is not a traditional 35mm or 120 frame.
Illumination. This is a big difference. The Nikon uses an IR-capable LED light source that can be used by Digital ICE to compute away most dust and scratches. This light source can be adjusted in intensity as necessary to penetrate dense negatives. The Flextight uses a cold-cathode tube (in the 343, it’s basically an off-the-shelf 6w daylight tube) whose intensity is not variable (scanning speed, however, is). The lack of Digital ICE is partially offset by the fact that the Flextight’s tube is a more diffuse light source that tends to cut down on the effects of dust and scratches.
Speed. The Nikon is much faster as a “proofing” machine, particularly with programs like Silverfast and Vuescan, which can preview and scan frames at many times the speed that a Flextight can. The Nikon (and similar scanners) use a positioning motor that addresses a an 18cm area and a stepper motor to advance the film across the scanning head over a 9cm area. Programs like Silverfast highjack the positioning motor to do a quick scan of the whole 6×18 preview area.The Flextight, for its part, moves so slowly that its operation is barely detectable until it hits the end of a scan and ejects the negative holder.
Negative size. There is a huge convenience factor in scanning a 6×12 or 6×17 negative in one pass without stitching multiple scans together (the Nikon has a positioning motor that can address 6×18, but the stepper can only do 6×9). You can set the scanner and pay attention when it kicks the negative holder out at the end. That said, the 343 only handles a maximum of 5 frames of 35mm film in a strip, though with an aftermarket holder, you can do two at a time. The biggest holder available is 58×184, which normally does 3 6×4.5, 3 6×6, or 2 6×9. The 6×4.5 capacity is a bit diminished compared to the Nikon where cameras space more widely (like the Fuji GS and GA cameras).
Focusing. The big difference between a Nikon and a Flextight comes in the focusing. Because negatives can be all over the place on the Nikon, it needs to focus – and you have to arbitrarily pick your focus point. The 343 avoids this by having focusing fixed at the factory (the grown-up Flextights can focus to a degree). As long has your holders have the right thickness of metal, focusing works great and without the clack-clack-clack of Nikon focusing.
Optical Path. The Flextight – like the Pakon 235 and 335 – has the CCD pointing down, through a lens, at the film. This has the effect of eliminating a dust surface and also helps keep things clean. The Nikon (and most negative scanners) turn light 45 degrees via a mirror that, depending on its care and feeding, might get dusty. Might.
Software. This is perhaps one of the weirdest comparisons imaginable. The Flexcolor software that comes with the 343 is about as basic an application as you can imagine. There are very few controls aside from original media type, curves, brightness/contrast, sharpening, and frame size. The most complicated thing about Flexcolor is understanding how to tell the scanner what holder you are using (picking the wrong one can lead to some strange noises).
For the Nikon, since Nikon Scan is deprecated, your choices are Silverfast (which is really powerful but really special in its user interface “innovation”) and Vuescan (virtually free but difficult to control and prone to blown-out, yet somehow specked, highlights). You can, of course, use Nikon Scan with Windows XP (and possibly 7). And speaking of XP, Silverfast 6.5 has wonderful medium-format frame detection with a Nikon scanner and Windows, not so much with Silverfast 8.
Equipped with the ability to recall multiple profiles and settings combinations, Silverfast seems to have much better capability to produce a usable scan without user intervention; Flexcolor seems to anticipate post-processing by the user, not in the least to correct the sharper-than-average dust and scratches. Oddly, Flexcolor defaults to unsharp masking at 250% – is this why the Flextight has such a reputation for crazy sharpness? Not really. The Flextight is no slouch set at 0, and the zero setting will give you a lot less film “grain.” More on this later.
Durability. There are three major aspects to durability. First, are the negative holders going to fall apart? I am fairly convinced at this point that Imacon, Nikon, and Polaroid designed their negative holders to be the weak link in what is otherwise bulletproof hardware. The Nikon FH-869 has little locking barbs that eventually wear out, and the Sprintscan 120 had a medium-format carrier with little locking pins that seemed destined for failure. Luckily, if that happens with the Nikon or Polaroid, you can just get a 3mm AN glass from Focal Point in Florida and use that instead of the top cover. Actually holds film flatter anyway. The Flextights, likewise, seem to have consumable carriers in the sense that the magnetic material will eventually experience fatigue and crack, particularly if handled roughly. Fortunately, there are Chinese replacements on Ebay that work perfectly for 1/3 the price of a Hasselblad replacement.
Second, is there a likely mechanical failure in the future? The CoolScan series of scanners has a phenomenally long service life. The Flextight looks almost too simple to fail.
Finally, what about bulbs? The LED light source in the LS-8000 has a lifespan measured in years of continuous use. The fluorescent tube(s) in a Flextight, provided that you can live with less color correction, cost a couple of bucks apiece and are easily installed by the user.
Relative performance. Over the next few weeks, I plan to run some hard comparative tests, but I’ll share some preliminaries. First, 2000dpi and up is where it becomes clear that your zone-focusing a 58mm on a 6×12 camera leads to some things being in focus and other things not. It remains to be seen how much more useful detail is actually generated going to 3200dpi (Flextight) or 4000dpi (Nikon). As someone who scans primarily TMY in 120, I can observe that the Flextight does not interact with grain quite as obviously as the LS-8000 and that the Flextight is a little more graceful when it comes to dealing with thick highlights. The Nikon in general creates more “grain” (or whatever) there with Silverfast, and Vuescan is very difficult to control in that area – and often ends up being worse. I plan to do some more testing with overexposed TMY and some older, denser negatives on things like Verichrome Pan. One thing that is clear on the Flextight is its ability to deal with not-so-flat negatives and equally resolve grain all the way across the frame.
One concrete comparison. Here is a comparison between a Flextight 343 and a Polaroid SprintScan 120 (this is an easy comparison because it does not require me to cut individual negatives to fit the Nikon carrier). The Polaroid here is being used with its AN glass carrier.
The test is a 320 pixel-high section of a Flextight scan and a 400 pixel-high section of a Polaroid scan (left side of the building). I equalized the visual contrast between the two originals (the Flextight was a bit contrastier out of the gate with its software’s default settings) and then scaled the Flextight image up to 400 and the Polaroid down to 320. N.B. that the Flexcolor software was set to zero sharpening, as was Silverfast for the Polaroid (well, inasmuch as you can really turn off sharpening in Silverfast).
You could make several observations here (yes, the negative is slightly rotated as between scanners, but straightening it would have messed up the resolution…)
First, at native resolution, the Flextight (upper right) is a tiny (and I mean tiny) bit sharper than the Polaroid (lower left).
Second, when scaled down (upper left), the Polaroid benefits from the automatic sharpening-on-resampling that Photoshop does. If you put an unsharp mask on the original Flextight image (upper right), you would get the same thing.
Third, when scaled up, it’s actually hard to see that the Flextight gives up anything to the higher-resolution scanner.
Finally, 4000dpi reacts really poorly with grain on Tri-X, almost as if the grain is at the Nyquist frequency for the scanner. Once the grain gets into the picture, scaling down makes it worse. By contrast, scaling up a 3200 dpi image does not result in even as much grain as a 4000dpi gets at its native resolution.
All of this is generally consistent with more casual comparisons between the 343 and the Nikon. Unlike the comparison between flatbeds with their “fake” bazillion dpi resolution versus real resolutions that are much lower, higher-end dedicated film scanners actually track very close to their nominal resolutions (a Nikon LS medium format scanner has hit 3,900dpi in German tests, for example). So one logical conclusion might be that as between a 3,200 and 4,000 dpi scanner on a relatively coarse-grained film, that last 20% is essentially empty magnification.
My takeaways. This observer would suggest that the Flextight story of superiority is true but not for the “sharpness” / film-flatness reasons that always seem to be bandied around.
First, as against a glass negative carrier, there is zero, zip, zilch to suggest that the Flextight is markedly superior to higher-end dedicated negative scanners. Film only needs to be flat enough that all of the grain is within the depth of field of the scanner lens and that it not be bucked so much that there be visible distortion. Where a scanner autofocuses, it focuses on the middle of the negative, not the edges that may sit lower or higher compared to the focus point. So when you get to the point that a scanner can focus on the center of the frame yet resolve film grain at the top and bottom edge as well as a Flextight does, you’re already where you need to be. Most glass carriers will achieve this, as will a standard carrier where the top latches have been replaced by a sheet of AN glass.
Second, scaling a Flextight scan up to 4000dpi tends to demonstrate that 4000dpi is not a quantum leap in resolution that bicubic interpolation cannot make up. Even 3200dpi on a negative will yield enormous prints (looking above, you will see that even the apparent size difference at 1:1 between 3200 and 4000dpi is tiny. No Flextight except the most recent X1 and X5 (both of which cost as much as cars) has better resolution for medium-format film than the 343 does.
Third, for situations where 3200dpi does not interact badly with film grain, the Flextight actually does better at original and upsized images than a 4000dpi scanner will. Grain aliasing is significantly reduced with T-Max 400. Progress.
Fourth, for oversized scans of 120 film, it is easier to get things flat in a Flextight carrier than a typical glass carrier for a dedicated negative scanner.
Finally, the Flextight is dead-quiet when running, which is a lot more than I can say for the rat-tat-tat-tat of stepper-motor driven units.
Scanners like the LS-8000 have their advantages too.
One, the Nikon scanners can scan negatives far faster, which means a big productivity increase when a big part of your scanning is previewing.
Two, the Nikon has Digital ICE, which can overcome film defects far more severe than the cold cathode light source of a Flextight can overcome. The flip side of this is that the LED light source in a Nikon is both permanent and harsher, which increases the contrast.
Third, glass carriers are far more flexible when it comes to scanning irregular, damaged, or strangely proportioned negatives. Flextight carriers have to be able to hold negatives on three sides to hold the negative flat – and that means that every deviant negative size requires a separate custom-made holder.
Finally, Flextights are not efficient scanners of mounted slides, and with an autofocus scanner, mounted 35mm slides are flat enough that the Flextight is not going to return a massive increase in flatness (more expensive Flextights can deliver far higher resolution, up to 8000dpi though – but for the cost of a higher-end Flextight, you could have a lot of actual drum scans done of your favorite work…).
Conclusion. It might be six one one, a half-dozen of the other. A Flextight is a great scanner for medium-format film, but it is not the most versatile (or in its most affordable forms, the most supported) dedicated film scanner. And if you have an LS-8000 or -9000, a Flextight will not necessarily rock your world.