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Marco Frigerio
15-Feb-2006, 03:50
Hi everybody from a cold and rainy Italy! ;))))

I've been offered an Howtek 4000 by my lab to scan my 8x10" trannies, but I have some thouhgts/doubts...

Based on what I see on the web, expecially the "A collaborative scanner comparison" here in the LF website, I don't see such enormous differeces between the Howtek 4500 scans and the ones you can obtain with an high end CCD flatbed, while I see enormous differences and ostanding quality while looking at the ICG scans and Heidelberg Tango scans, and I know why, these drum scanners are much better than the Howtek ;)))))...

Now, my doubt is: is it worth to face all the difficulties and the steep learnig curve of drum scanning purchasing an Howtek 4000 if I can obtain very close results with a refurbished Creo at almost the same price?

Or maybe it's better to save money and find a refurbished ICG or Tango if one is seriously interested in drum scanning? (btw, I've been offered an ICG 350 too, but is mauch more expensive than the Howtek!!)...just to give you an idea of my printing needs: I usually don't enlarge more than 5x my 8x10 originals (40x50" prints) but I have a particular work in mind that "requires" enlargements in the 8x-9x range (72x90" prints )...

If somenone could give me some "real life" advices I'll really appreciate that...

Thank you.

Ciao

Marco

Bobby Sandstrom
15-Feb-2006, 07:35
Marco:

Call Aztek. I just had a conversation with one of the tech guys there (extremely knowledgable) and he wasn't thrilled with the scanner you mention. Give him a call or drop them a note. I can tell you I recently had some drum scans made with their scanner (8x10 black and white negs) and was blown away! I've seen that comparison article you refer too and agree with your assessment. I think you'll find your answers by talking to these people.

http://www.aztek.com/QUESTION.HTM

Good Luck!

Bob

Dominique Labrosse
15-Feb-2006, 08:55
Marco,

Like a camera, a scanner is only a tool. I've seen some awful scans made from some great equipment. Sure the equipment is important but the scanner operator is more important than the equipment.

CXC
15-Feb-2006, 10:39
Don't buy anything you have doubts about. Even if it seems cheap now, very likely it will turn out to be wasted money.

Eric Jones
15-Feb-2006, 10:48
Hi Marco,

Having owned a Howtek 4000 I could not have been more pleased with the results I was able to obtain from it. Technically it is a very capable scanner and has features such as 12 aperture settings for optimizing spot size to grain size (important with color and B&W negs), very true and respectable DMAX and resolution and decent bit depth (12 bits). In my own comparisons it beat out all of the consumer/prosumer flatbeds (including wet mounting) and the consumer/prosumer dedicated negative scanners. If the price is right (I put together my system for $1800 US including new Lasersoft Imaging software) and the scanner you are considering has been well maintained I think you'll be very happy with the results, especially coming from 8x10 originals.

Best,

Eric

bglick
15-Feb-2006, 13:46
Eric is right....the 4000 and more specifically the 4500 are excellent scanners if properly tuned and working up to par and using the right software and a knowledgeable operator. for the money most sell for you, you can't touch the quality. The 4500 / 8500 have consistently outperformed the Tango, which was an early version drum scanner, which was quickly superceded by others before the entire field went belly up. The biggest risk with the old drums is repairs....one good repair, and you pretty much lost the investment. Considering ICG's sell new for $50k, well, it shoudl be good! I still question the results on this web site regarding that scanner, anything could have happened, but I doubt it should outperform that much better, assuming all parameters were equal....

Bruce Watson
15-Feb-2006, 15:24
The web pages are useful tools. But you can't make definitive judgements about final print quality without looking at prints. It is in prints that you will see the real differences between different scanners, software, and operators.

Which scanner to pick depends largely on what you want to scan. If you are only scanning trannies, all the drum scanners do very well. Trannies was their primary mission. If you also want to scan negatives, including B&W, then you should look to the "table top" scanners like the Howteks, Optronics CologGetters, Screens, and ScanMates. Their mission was more as general purpose machines, and their software often handles negatives better. I'd include the ICGs in there as well, but IIRC their software is strictly 8 bit, which is insufficient for negative work IMHO, especially for B&W. I'd include the Tango, but it's minimum aperture is just 11 microns making it less sharp than the others, and it's software is supposed to make negative work difficult.

Then, part of it depends on what enlargement factor you want to scan to, and what the limitations are from the scanner hardware/software and computer OS. In other words, you aren't going to be scanning 10x8 color film at 360ppi output, at 10x enlargement. The resulting file size is considerably bigger than modern computers can handle. Anything over about 2GB is going to be nearly impossible to work with until PC/MAC OS software, and Photoshop, go fully 64 bit. Do the math and see how big a file you think you can live with.

Why is this important? It bears on whether or not you should go with a pro level flatbed or a drum scanner. If all you can do is a 5x enlargement, then the flatbeds should be sufficient. Drum scanners don't really begin to shine until you are in the 8x or more enlargement levels.

For context, I own and run a ColorGetter 3 Pro with ColorByte's ColorRight Pro 2.0 software. Like wg, I think my scans are better than Tango scans. But your getting the right scanner for you depends on your knowing what you actually need.

QT Luong
15-Feb-2006, 20:35
How come that several well-regarded labs such as Nancy Scans and WCI use the Tango and claim that it is the best thing since sliced bread (well, maybe not, but at least the best scanner) ? Calypso used to have an ICG that produced results that looked pretty good to me, but recently switched to a Tango, and also said that it was a big improvement. I am not questioning Bruce and WG's wisdom, just curious.

bglick
15-Feb-2006, 21:17
QT, this is my guess of what happened.....

When the Tango was released, I beleive 1997, it was a breakthrough scanner at a breakthrough price, only $60 - 80k vs. prior drums in the 150k + price range. However, its supremacy was quickly surpassed in 98 - 00, but Tangos marketing hype was never forgotten. When Sybold ran a comparative test around 00, the Tango performed from mid to poor against competing flatbeds and I beleive one or two drums (Howtek was not in the test, as they were not a pre press company) The only reason i quote the Seybold test.... it allowed each manufacturer to provide the scanner and their own operator to run a serious of tests on the same targets, then the results were numbered, not named, then judges compared the scans in several different aspects, so this test was as unbiased as you can get. I have seen no such tests since that point in time, as scanners in general began to fade.

As for Tango vs. Howteks, the Howtek has a much smaller aperture to record data, I think 2 or 3 microns smaller, which eqauted to about 30% in size, which enabled sharper scans at the same dpi. The same is true of the ICG scanners. But even with all this, the Screen Cezzane Elite flatbed out performed them all, within the Seybold test parameters.

But not all Howteks are created equal...I have owned 3 of them, and the image quality varied for different reasons. Howtek was always on a tight budget and had very poor quality control (if any at all) ....this is what Aztek added to the equation, they tweaked the scanners and required them to pass certain tests before they were sold as Aztek. This does not mean a Howtek can not equal the quality of a Aztek, its just hit-or-miss as the industry just could not fund itself, and Howtek bailed out of scanners as did Heidleberg. I think the Tangos life ended in 00 or maybe 01, short lived indeed.

I veiwed many Tango scans from WCI, and re scanned them on a howtek 4500 and 8000 and the howteks were noticeable better, but my Howtek was well tuned. Not knocking WCI in anyway, from what I hear, people are happy with their customer service. Anyway, thats my take on it!

Marco Frigerio
16-Feb-2006, 01:39
Thanks for all the useful answers, lots of stuff to think about, thank you!!

Ok, so the main "problem" with the Howtek is that I could buy a "poor" fine tuned unit due to the "poor" quality control (mmmhhh, it seems like a russian roulette ;)))))) )...but, having no experience with drum scanning, is there a way so that I can understand if the unit I'm purchasing is fine tuned or not?

Thank you

Ciao

Marco

Bruce Watson
16-Feb-2006, 09:31
QT,

To add to what wg said:

The laws of physics tell you that spot size is what determines sharpness. You can see this by scanning a reference target like the old 1951 USAF resolution test target. Scan at a bunch of scanner resolutions and you'll see that you get a maximum optical resolution that is consistent with the spot size. And spot size is aperture size.

So if you want the best in sharpness, you probably want the new Screen drum scanner. IIRC it's the only scanner on the market (that is, that's ever been on the market) that has a fully adjustable aperture size. This lets the scanner make an exact match of the spot size to the resolution you need, whatever that resolution may be. It should be very nice indeed.

Failing that, you should look for a scanner with at least a 6 micron aperture which will give you an optical resolution in the 4000 ppi range (depending on lots of other factors, like the quality of the optics). The high end ICGs and Azteks now have minimum apertures in the 3 micron range, giving an optical resolution that's something less than 8000 dpi. In comparison, the Tango has a minimum aperture of 11 microns IIRC.

The story I've been able to piece together from several operators and pre-press people is that the Tango was aimed squarely at the advertising and fashion market. It was a reaction to the Howteks, Screens, Optronics, ScanMates, and other scanners that were aimed at the smaller pre-press and short run press houses that couldn't afford the big Hell, DuPont/Crosfeld, and Heidelberg scanners. These new "table top" scanners were much cheaper, and more versatile - both were required by their target market. The Tango met the competition on price (sorta) and size, but was optimized for Heidleberg's traditional market of the advertising and magazine world. As such it was heavily optimized for chromes and for smaller enlargements (thus the 11 micron aperture). It's a marvelous machine for cranking out magazine pages, and the pre-press people just loved it, which is part of it's enduring reputation.

These days the vast majority of film scanning is by the the fine art crowd -- us. And we don't play to the Tango's strengths. Many of us choose to shoot on negative film, and I've heard that the software (currently called NewColor IIRC) was so optimized for chromes that doing negative work is a chore. Many of us want to make fairly big enlargements, and the larger minimum aperture of the Tango makes for large prints that aren't as sharp as they could be. What doesn't matter to a model's face on a magazine page matters a great deal to a landscape photographer who is after highly detailed and sharp prints.

The Tango is a fine machine when used as intended. All I'm saying is that it wasn't intended for the fine-art market.

Also, what would you expect WCI and NancyScans to say about their equipment? Maybe I'm a cynic, but I think you'll be waiting a while for any company to say that their equipment is anything other than the very best, no matter what that equipment is or what kind of a match it is to your needs. I'm just sayin'...

QT Luong
16-Feb-2006, 12:09
Bruce, let see if I am following your story well. I don't see why the "Howteks, Screens, Optronics, ScanMates, and other scanners that were aimed at the smaller pre-press and short run press houses" would be better suited for fine-art scanning than the Tango. So is it that subsequently, those companies introduced new scanners targetted for the fine art market ? Also, isn't the reproduction ratio often higher in pre-press than fine art because most of the film used in magazine publication is 35mm ?

Regarding aperture size, in practice, at what scanning resolution would you notice the difference between the Tango, and the scanners that you mention with smaller apertures ?

bglick
16-Feb-2006, 12:15
Bruce, excellent analysis....I would like to add a few notes.....

What confused many about Tango is their high end scan numbers, I think 11k dpi. Well, even an Epson 4990 can scan at some very high numbers, but not effectively, as you end up with a super large file of mush, this is what seperates better scanners from heap - sharpness at small file sizes is the goal of a fine art scanner, and when your in the fine art market making big prints, the difference between 500MB and 1 gig files is huge.... hence, why you pay so heavy for the better scanners, albeit, this is also what makes digital capture so damn appealing, the capture process is so much more efficient, even using the best film and best scanners of today. hence why I can't keep my fingers out of the digital capture world. I feel as if I understand this efficeincy process as well as anyone, which makes me a huge digital fan, yet in these forums, I get bashed for being pro-film, oh well....

Although micron size began to be the holy grail to resolution for fine art / large enlargement work, just like photographic lenses, there is points of diminishing returns. Your correct about the Screen and Azteks improved micron size, but I found this the following interesting...... with film, say color film, it will only hold a max. of 30 - 60 lp/mm of detail, based on the film being used. So the key for scanning color film is sharpness at these frequencies, which is under 4000 dpi. At these levels, I have spoke to operators who use both the Screen 8060's new drums and the Screens Cezzanne Elite flatbed. They have done a ton of comparisons, and their conclusion is, unless a scan has to be made over 5000 dpi, such as super detailed B&W shots which holds 2 - 3 x the detail vs. color film, it gets done on the flatbed. As for Dmax, they claimed the differences were in the 1 - 2 % range, not even detectable to the eye. So, my point is, there is more to the equation, just like other optical mechanical devices that have so much complexity from film to file. BTW, Screens software is optimized for color neg scanning, and whats neat is they have it profiled for the new color negs films using the new bases optimized for scanning, which started with Reala in the Fuji line.

bglick
16-Feb-2006, 13:00
QT, some cross posting, i will try to respond.....

You are correct that in magazine repros., a 35mm piece of film can be pushed to its limits for a full size two page display.... and the Tango certainly catered to that market, hell, that was their only market, mainly pre press companies, but the scanners were small potatoes to them, as they were after the presses and computer to plate systems.

There is a mathamatical relationship between micron size and point size on film. There is 25,400 microns to the inch, so an 11 micron sensor (Tango), is equal to a spot on the film of 1/25,400 * 11 = .00043.... now, in ppi world, this is, 1/.00043 = 2,309 dpi. So if one buys into the micron = spot size, in theory, the Tango sensor is only capable of seeing 2300 dpi, however, there is more to the equation then this and we all know, no optics is linear in its ability to resolve, the fall off is dramatic towards the higher frequencies.

In drum scanners, the ability to tighten the threads of the scan (drum scanner is nothing more then threads on a screw), is also a determining factor of resolution. The Tango probably did an excellent job in its ability to tighten the threads on the film, which is probably how they attain the 11k dpi claim. But the optics will need to interpolate this data a lot, as its not as precise as the hardware would have liked. But as with all optics, specially with LF lenses, we see the same fl, the same aperture, the same target, etc, and yet digitar lenses our resolve other LF lenses by a factor of 3. And there still is the MTF issue.... of course, none of these numbers are ever published, and its my guess, since the market came and went so fast, even the makers do not know them. hence why the easiest determining factor boils down to side by side tests with the actual film you plan to scan as well as the software for both machines. Then, we have the tuning issue, so the variables are a witches brew of possibilities.....

for resolution, sound testing invovles scanning targets, as real worls subjects are to subjective in the analysis process. As in the sybold tests, they took scanner targets, and made each scanner perform scans at a given dpi, then made an analysis of the digital file, and made conclusions of the scanning efficiency. Meaning if they scanned at 100 lp/mm, but could only resolve 95 lp/mm, the scanner is 95% efficient. Which, btw, is the best of the batch, many of the expensive models were in the 75% range, while many consumer models can be at the 30% range.

To me, as for resolution aspect of a scanner, this test is the culmination of all the factors involved in scanning. Plain and simple, this is the test that determines what the scanner is really resolving at a given scan resolution. My guess is, you would see Tango scans start degrading vs. their better competitors at around 1500 dpi, something less then its optical potential. But remember, most color film doesn't have more then 2500 dpi to begin with, so these numbers are not too rediculous, unless you are scanning Velvia for big enlargements, then the differences begin to surface. In my case, I saw noticeable differences in the 8x + enlargement range, i.e. Tango vs. howtek. Considering the market for film scanners have been reduced to ebay sales selling for pennies on the dollar, (other then a couple of makers that still exist on the high end) I doubt we will ever see any more analysis, life has moved on to digital capture :-) It's only us dinosaurs left !

Bruce Watson
17-Feb-2006, 08:35
So is it that subsequently, those companies introduced new scanners targetted for the fine art market? To the best of my knowledge, no company has ever sold a drum scanner aimed at the fine art market. My point is that the general purpose machines may do a better job with the demands of the fine art market than machines that are specifically aimed at the advertising market. This is particularly true when you get to negative films.

isn't the reproduction ratio often higher in pre-press than fine art because most of the film used in magazine publication is 35mm? It could be about the same. When people are trying to maximize image quality, they tend to stop at about 10x enlargement. If they need bigger, they go up in format. It's the advertising industry that gave rise to the 645 format after all.

More importantly, the advertising and magazine markets often will trade sharpness for smoothness. For example, if you are showing a model's face, would you choose sharp grain or smooth tones? Heidelberg knew the answer to that one which is why they picked that 11 micron minimum aperture. They optimized for smoothness over sharpness to meet the requirements of the target market. And that's not at all a bad thing. But if you want to use a Tango for fine art work, you should recognize that this trade off was made.

Regarding aperture size, in practice, at what scanning resolution would you notice the difference between the Tango, and the scanners that you mention with smaller apertures? Like most things, it's going to depend on the image, the scanner, the software, and the operator. As wg says, it's a complex system. All other things being equal (an impossibility, but still), I suspect that you would start to see differences in the 2000 ppi range, and will certainly see them by the time you hit 4000 ppi.

I suspect that the Tango's sharpness limitations are one reason that a number of "name" photographers say that "you can get all the detail off film by 2000 ppi." Because with a Tango, that's probably true. Unfortunately, this is the kind of half-truth that spreads easily. Before you know it, people are applying this litany to all scanners, true or not.

bglick
17-Feb-2006, 11:07
Bruce, actually, I think these half truths have some reality to them, BUT, under the right curcumstances. The confusion usually exist with the application of whats being scanned and how efficient the scanner is.

For example, if you shoot a test target with color chrome film, with the best LF lenses (NOT MF or 35mm lenses) you will record between 35 - 50 lp/mm throughout the different areas of a 4x5 (not 8x10) piece of film (non velvia, an exceptionaly high resolving color film). So if you shot a flat subject, this is what you can record throughout the film, so lets use 43 lp/mm as an average, which equates to 43 * 50.8 = 2,184 dpi. Assuming the scanner records at 90% efficeincy, you would need to scan at 2184/.90 = 2427 dpi. This would record approx. 80% of all the rez throughout the film, if you wanted to scan for the higher resolving center portion, so maybe 2800 dpi. This is where the mis understandings begin, very few of us shoot test targets in a lab.

Since very few shots are of flat sujbects, once you add DOF to the image, both the defocus principle and aperture difraction both severely degrade the recorded resolution. If you averaged near to far, the 43 lp/mm would be closer to 30 lp/mm, or 1700 dpi scan after efficeincy. At this scan rezolution, you would only loose a very tiny bit of resolution at the "point of exact focus", which usually represents less then 15% of the total scene, but regardless, the scan levels are relatively low.

Now, if you use Velvia, it will kick up the numbers up to 30%, if you add an inferior scanner in the mix, say 70% efficiency, you divide by .70, and the required scan resolution grows again, which will create a larger file, but not contain anymore useful information. (just more cumbersome to work with) If you use good MF, such as M7 lenses and Velvia, the numbers can jump another 30% just for arguments sake.... so there is a need for higher resolving scanners indeed, but, for LF scenes with no lens tilt, and shot at f32, the numbers are a bit less then most think. Of course, it never hurts to scan a bit higher then needed, assuming you are not exploiting the grain of the film, then, you can down-size the file and gain a bit of resolution with a slightly smaller file.


So, it's the application of several factors that dictate the optimum scan resolutions. (optimum = pulling all resolved data off the film without overscanning to the grain) In the color film world, to exploit everything in the film, a high / low scenario can be something like this....

High Scan scenario
35mm sharpest lenses, flat subject, Veliva, high contrast subject, low eff. scanner
65 lp/mm * 50.8 / 70% = 4,700 dpi scan required, quite high indeed.....

Low Scan scenario
8x10 format, ISO 200 film, avg sharpness lens, f45 for DOF, low contrast subject, high eff. scanner
20 lp/mm * 50.8 / 95% = 1,100 dpi scan required, quit low indeed.

As you can see, this is a 400% swing in required scan resolution, quite extreme. So, in general, the image capture details is what should drive the scanning requirements (other then scan eff. factor), not vica / versa. For those who pay for scans, this can save some big $$, and for those whow work on large files on undersized PC's, it is also helpful to keep file sizes at their smallest but most optimum levels.

Just my $.02 .... your mileage may vary

QT Luong
17-Feb-2006, 12:03
Do those numbers imply that for 35mm film, besides Dmax there is little point of scanning on the Tango rather than on a desktop film scanner ?

I understand that the labs have to say that their scanner is the best, but why would they choose the Tango to begin with, when they cater to the fine art market like WCI and Calypso does ? Calypso for instance makes huge prints from 35mm for the late Galen Rowell and Franz Lanting.

Bruce Watson
17-Feb-2006, 14:56
wg, I did say it's going to depend on the image, the scanner, the software, and the operator. IOW, I think we generally agree. Clearly smaller formats need higher scanner resolutions, and therefore smaller apertures. But my experiments with my own 5x4 Tri-X shows me (and the 10 other people I showed it to in a highly unscientific experiment) that there's a visible difference in sharpness of prints when the only difference was the 6.25 micron aperture vs. the 12.5 micron aperture that my scanner has available (I was scanning at 11x, output at 360ppi (overkill, but I wanted to take up-rezing software out of the equation). For sharper films in this size I would expect it to be even more visible. For smaller formats I can see a need for a 3 micron aperture, but I can't imagine that anything below 6 microns has any meaning for LF users ;-)

QT, scanning providers have somewhat different needs than individual artists. They are betting their business on the scanner, so they need service contracts and parts availability. They also need throughput, and a Tango runs significantly faster than my old ColorGetter 3 Pro. Also, as pre-press houses continue to shut down, used Tangos are available a significant savings over new ICGs and Azteks. But it's the first two things alone will drive them to stay with currently available scanners.

As parts and service become more of a problem, I imagine that they'll move on to scanners from the last manufacturers standing - ICG, Aztek, and Screen. And they will say that whichever one they bought is the best. But they'll still mean the best for them, not necessarily the best for the artist. But that's not necessarily a bad thing as long as there is still film that needs to be scanned and companies that are willing to scan it.

Bruce Watson
17-Mar-2010, 10:22
Mea culpa. Boy did I screw this thread over. Turns out I was factually wrong about the Tango's minimum aperture. The real answer is that Tangos have an aperture wheel with 25 apertures available. The smallest aperture is 10 microns, not 11 micons.

This doesn't much change my conclusions about the Tango, but it's still misinformation that needs to be corrected. So I'm correcting it now. Better late than never I hope.

My information comes from Karl Hudson of Hudson Grafik Services, Inc. (http://www.hudsongrafik.com), a guy who makes his living repairing and maintaining these (and other) machines. He should know is anyone does.

Lenny Eiger
17-Mar-2010, 11:56
is there a way so that I can understand if the unit I'm purchasing is fine tuned or not?
Marco

When I bought my last scanner, I had it sent directly to Aztek for tuning/maintenance. I also made a deal with the seller that if Aztek said it was a useless bucket of bolts that I wouldn't pay for it - I was only out the shipping costs.

Lenny

Lenny Eiger
17-Mar-2010, 13:10
I'll add my 2 cents here. First of all, a Tango is not a Premier. I hired someone to do a scan on a Tango, an experienced operator and got a scan that wasn't as good, quite visibly I might add, than the Howtek 4500. (The one I purchased right after I figured out how much it was going to cost me to do all the scans I wanted.) I will say there are likely a couple of people that can get quality out of a Tango that others can't. There is some hot-wiring they can do, apparently. Cramer sent me a test neg a while back and the Premier blew away the sharpness of his Tango.

I think the major difference isn't the aperture itself. The Premier can do 3 microns. However, there isn't any film (non-military) that can scan that low without showing grain anti-aliasing. That said, the mechanisms to support a 3 micron result require twice the "sharpness" required to do a 6 micron scan. The Premier moves over a 64,000 of an inch with each pass (turn around the circumference). Every part of the process, from the lead screw, to the components in the optics box have to be better made, have higher tolerance.

Given this, I entirely and totally reject all notions of there is only so much detail in a particular image based on film format, fstop, etc. It simply hasn't borne out in my testing. Every test that indicates that there is no more detail than 4K, for instance has been done with a scanner with limits at that level.

The other aspect is "how to scan" an image. Most folks in labs are going to give you a top and bottom that isn't clipped and let the scan run... WCI's and NancyScan's business model is one of volume, get the project out the door. In my opinion, setting white and black points isn't how to scan an image, certainly not in b&w. Other folks make the image look like they want the print to be. That isn't right either. If you want to be successful at scanning, you have to give the photographer the capacity to make the print they want. A lot of film compress the midtones, or a certain section of the midtones, lighting affects it, etc. Certainly it should give the ends a wide berth, but it should also separate with micro adjustments, each area of the midtones so that the printer can grab these sections with a mask and manipulate them to get the desired effect. The better a printer someone is, the more subtle their vision is, the better a scan you will get.

Further, I say screw resolution. It's too easy - for any drum scanner (and not consumer machines). Especially when printing with an inkjet. I can do a scan with any size film that will show the edge of a building sharp, at say 16x20. I don't bother opening up the lens to a wider aperture because the difference is so minimal it's silly, IMO. I'm building an iPhone app, as many of you know, and I didn't bother with a depth of field, or hyperfocal distance calculator, because I think its a waste of time. Close the lens down and get some depth of field! Use a loupe to see if things are in focus.

The real meat of a great scan is whether or not you can deliver all the tones of the original scene, and separated out so that you can print it. That's the hard part.

Lenny

zhengjdc
21-Apr-2011, 07:13
I think the major difference isn't the aperture itself. The Premier can do 3 microns. However, there isn't any film (non-military) that can scan that low without showing grain anti-aliasing. That said, the mechanisms to support a 3 micron result require twice the "sharpness" required to do a 6 micron scan. The Premier moves over a 64,000 of an inch with each pass (turn around the circumference). Every part of the process, from the lead screw, to the components in the optics box have to be better made, have higher tolerance.

Given this, I entirely and totally reject all notions of there is only so much detail in a particular image based on film format, fstop, etc. It simply hasn't borne out in my testing. Every test that indicates that there is no more detail than 4K, for instance has been done with a scanner with limits at that level.


Lenny

have to disagree with you over this.

I had captured a good contrast scene with Canon 24mm 1.4L lens with EOS 3 body, mirror locked, tripod mounted, Provia 100F and did a 4000dpi scan over my Howtek D4000 just yesterday.

The drum scanner did amazing jobs but however it still failed to capture a tiny piece of information on the film. As I examined the film under microscope, some parts of the film still hold slightly more details than the 4000dpi drum scanner can see, especially the part where it has really high contrast, such as small banners with white backgrounds, in which I can figure out the words under microscope but not so with drum scanning picture. I supposed for a good 35mm color film, with superb lens, you might need something at 5400~6000dpi range to capture EVERYTHING... but 4000dpi drum scanning is good enough to live with as it blows away any CCD scanners.

I supposed with the newest t-max B&W film, you might need a drum scanner at 8000dpi to capture 100% details, as t-max holds even more details than Provia 100F.

Noah A
21-Apr-2011, 08:19
...

Given this, I entirely and totally reject all notions of there is only so much detail in a particular image based on film format, fstop, etc. It simply hasn't borne out in my testing. Every test that indicates that there is no more detail than 4K, for instance has been done with a scanner with limits at that level. ...

This has been my finding as well after testing various scanners and after doing tests with my Howtek HR8000 at various resolutions.

My philosophy of scanning has always been to ignore how much resolution is actually on the film itself. My goal is to reproduce the piece of film as accurately as possible and translate that information into a print. So if I scan a crappy holga negative, I still want to faithfully reproduce the grain (or dye clumps) of the film onto a print.

In short, I want my lens or photographic technique to be the limiting factor in the resolution of my prints, not the scanning or printing. Really a drum scanner is the only way I've found to accomplish this (short of a darkroom contact print, of course, but this is a digital discussion).


...
Further, I say screw resolution. It's too easy - for any drum scanner (and not consumer machines). Especially when printing with an inkjet. I can do a scan with any size film that will show the edge of a building sharp, at say 16x20. I don't bother opening up the lens to a wider aperture because the difference is so minimal it's silly, IMO. I'm building an iPhone app, as many of you know, and I didn't bother with a depth of field, or hyperfocal distance calculator, because I think its a waste of time. Close the lens down and get some depth of field! Use a loupe to see if things are in focus.

The real meat of a great scan is whether or not you can deliver all the tones of the original scene, and separated out so that you can print it. That's the hard part.



How true, and well said!

In general though, and back to the OP's question, while I wouldn't say that drum scanning is particularly difficult, it does require skill and knowledge, not to mention equipment that's in good shape. A Howtek 4000 can do great scans in the right hands. Any online comparison is relatively useless if it was done by different people with different knowledge and techniques.

Lenny Eiger
21-Apr-2011, 12:10
have to disagree with you over this.
I supposed with the newest t-max B&W film, you might need a drum scanner at 8000dpi to capture 100% details, as t-max holds even more details than Provia 100F.

zhengjdc,
I am absolutely certain that I am not right about everything... disagreement is welcome.
I haven't used a 4000, I had a 4500 when I started this, but now have a 8,000 ppi Premier. Last month, I was blown away at a print from a 6x7 neg (Ilford Delta) where I could read a speed limit sign from about half a mile away. It was a test I did against an 8x10, they both read the letters equally, altho' at 40 inches, the 6x7 was starting to show a mild "grainy" look vs the 8x110 which had full texture....

I think that the reproduction of small details is controlled by a lot of factors. It's hard to beat a microscope... Someone earlier stated something about a well-tuned machined, working perfectly, etc. I've had to have a PMT replaced - what might be the effect of that, or two out of three of them, for example. There is also some skills required, or at least having one's own scanner and being able to scan something multiple times until the right approach is taken... for the image.

I think the issue here is that if one controls the process from end to end that the bottlenecks will begin to emerge. Mine seems to be at the printer. It is only so capable. The scans are sharp, and deliver more than the printer can handle. During the process, however, I have also discovered my own aesthetic. I am interested in light, how it layers, what it means, and reproducing an experience. I like depth of field, but care little about absolute sharpness. I'd rather have 95% sharp with everything in focus than let areas go unsharp to have that critically sharp area. This is a personal decision, or set of decisions, and there are lots of other folk who follow a different philosophy and do great work.

I have just started to print on lightweight Kozo, a translucent paper at 70 gms and I'm having a blast. The light appears to pass thru the paper and bounce back of the white mat and the print is delicate like a carbon print, and luminescent. I'm having a blast with it.

Lenny

sanking
21-Apr-2011, 20:43
zhengjdc,
I am absolutely certain that I am not right about everything... disagreement is welcome.
I haven't used a 4000, I had a 4500 when I started this, but now have a 8,000 ppi Premier. Last month, I was blown away at a print from a 6x7 neg (Ilford Delta) where I could read a speed limit sign from about half a mile away. It was a test I did against an 8x10, they both read the letters equally, altho' at 40 inches, the 6x7 was starting to show a mild "grainy" look vs the 8x110 which had full texture....

Lenny

If you compare 6X7 cm to 8X10 inches with the same film the print from the larger film will always look like it has more texture. Next time you do this test you might consider using a slower, finer grain film in 6X7 cm to compare to Ilford Delta. I believe Fuji Acros would be an improvement over Delta 100 for 6X7 cm, if not try Rollei Pan 25, or Rollei Ortho 25.

Yes, use of either of these films will call for special developers and some experimentation to get it right. But maybe worth the trouble considering how much you can save on weight and size of equipment. Perhaps this is not important if working from a car, but for travel it sure is important to me.

Sandy

onnect17
21-Apr-2011, 21:54
have to disagree with you over this.

I had captured a good contrast scene with Canon 24mm 1.4L lens with EOS 3 body, mirror locked, tripod mounted, Provia 100F and did a 4000dpi scan over my Howtek D4000 just yesterday.

The drum scanner did amazing jobs but however it still failed to capture a tiny piece of information on the film. As I examined the film under microscope, some parts of the film still hold slightly more details than the 4000dpi drum scanner can see, especially the part where it has really high contrast, such as small banners with white backgrounds, in which I can figure out the words under microscope but not so with drum scanning picture. I supposed for a good 35mm color film, with superb lens, you might need something at 5400~6000dpi range to capture EVERYTHING... but 4000dpi drum scanning is good enough to live with as it blows away any CCD scanners.

I supposed with the newest t-max B&W film, you might need a drum scanner at 8000dpi to capture 100% details, as t-max holds even more details than Provia 100F.

4000dpi should enough to start seeing some of the grain.

Could you clarify the following?
Mounting fluid used,
Auto or Manual focus,
Emulsion facing in or out,
Aperture (scanner),
and Software platform.

Noah A
22-Apr-2011, 05:34
have to disagree with you over this.

I had captured a good contrast scene with Canon 24mm 1.4L lens with EOS 3 body, mirror locked, tripod mounted, Provia 100F and did a 4000dpi scan over my Howtek D4000 just yesterday.

The drum scanner did amazing jobs but however it still failed to capture a tiny piece of information on the film. ...

Unless I misread his post, Lenny is saying that folks who say film is limited to 4000dpi or less are using scanners that are not capable of higher resolution. Therefore they can't really say for sure if a higher resolution scan would provide more real information.

So I think you and Lenny are both in agreement. You both are saying that, while 4000dpi is great, film actually has more information than can be captured at 4000dpi.

And if you have a scanner (Like Lenny's Aztek) that can scan at a true resolution of higher than 4000dpi, you will see an advantage.

At least I think that's what you are both saying...forgive me if I'm wrong.

dongadda
22-Apr-2011, 08:01
I have taken up wet scanning of 4 x 5 transparencies on an Epson flat bed and could not be more please with the results. The average file is a bit on the gigantic size (1.4 gigs) but the end result is very pleasing and I frankly can see no improvement when looking at prints made from drum scans that I paid too much $$$ for. Don

Noah A
22-Apr-2011, 08:50
Just curious Don if you don't mind--Which epson are you using? How large are the prints you're comparing? And who did the drum scans?

Brian C. Miller
22-Apr-2011, 12:16
The drum scanner did amazing jobs but however it still failed to capture a tiny piece of information on the film. ... ... . I supposed for a good 35mm color film, with superb lens, you might need something at 5400~6000dpi range to capture EVERYTHING... but 4000dpi drum scanning is good enough to live with as it blows away any CCD scanners.


Why My Gigabyte Film Scans Might Not Be Good Enough (http://theonlinephotographer.typepad.com/the_online_photographer/2011/03/gigabyte-film-scans.html), by Ctein.

It's an interesting blog post with comparative scans of the same image crop.

Lenny Eiger
22-Apr-2011, 15:48
It's an interesting blog post with comparative scans of the same image crop.

He doesn't mention what scanner it is..... The numbers would suggest a consumer flatbed, not a pro scanner, but I don't really know....

Lenny

Jon Shiu
22-Apr-2011, 15:53
ctein quote: "...Minolta Dimage Multi Pro scanner, and it resolves 4200 PPI in the center of the field and 3800 PPI at the edges. 80–90% of theoretical resolution at a scanner's upper limit is very good performance"

Lenny Eiger
22-Apr-2011, 16:21
ctein quote: "...Minolta Dimage Multi Pro scanner, and it resolves 4200 PPI in the center of the field and 3800 PPI at the edges. 80–90% of theoretical resolution at a scanner's upper limit is very good performance"

Not bloody likely. I would not imagine that the scanner could do 4200 resolution.... and the images prove it... It's a CCD, an extra lens - there's such a thing as Physics... It's not a bad scanner, but I wouldn't consider those results excellent...

I didn't read the article too thoroughly, but if its meant to be some kind of bar, where you make a statement about what is possible, and what isn't, it ought to be done on a drum...

Just my 2 cents....

Lenny