On drum scanners and flatbeds

[Ben Syverson]

Recently I was mulling the possibility of getting drum scanner. I've seen a few really great working machines go for $1000 - $1500 with mounting station, drums and Mac G3/G4...

So I decided to revisit the scanner comparison page on this site. I selected my scanner, an Epson 4990, and the Howtek 4500.

The sharpened versions of the scans on the site have not been sharpened enough (or properly) for me, so I grabbed the unsharpened images and had my way with them. There's a lot of detail "hiding" in the 4990. Here's what I came up with.




I've done two passes of simple USM on each image.* To me, the Epson images arrive in the same ballpark as the Howtek scans...

Keep in mind that these images are 100% views of 2400 DPI 4x5 scans. If you were to print the entire scan at 40x30 inches (300 DPI, 8X enlargement), these detail crops would only be 1.666 inches wide. To put it in perspective, here is the fabric detail reduced to 72 DPI (life-size section of 40x30" print, if your monitor is 72 DPI):


I would have to see the actual prints in front of me, but I don't think I would be able to tell the difference between the Epson scan and the Howtek at 300 DPI at a reasonable viewing distance (say more than 12"). Then I started to think: I shoot mostly 8x10, and an 8X print yields an 80 x 60 inch image.

In other words, with a $200 discontinued scanner, I can make an 80 x 60 print from 8x10 that I can't distinguish from a drum scan, even up close. Cut, print, it's a wrap.

Any thoughts?

- ben

* On the first comparison, it's Epson: {300, 1.7, 0.0} then {200, 0.7, 0.0}, and on the Howtek: {84, 1.7, 3.0} then {112, 0.7, 0.0}.
On the second comparison, it's Epson: {200, 1.5, 0.0} then {164, 0.7, 0.0}, and on the Howtek: {67, 1.7, 3.0} then {91, 0.7, 0.0}.

[Ron Marshall]

[QUOTE=bensyverson;448591]In other words, with a $200 discontinued scanner, I can make an 80 x 60 print from 8x10 that I can't distinguish from a drum scan. Cut, print, it's a wrap.

QUOTE]

As long as you are satisfied, there is no point spending extra money.

Have you had a drumscan made of one of your negs or positives?

[aphexafx]

Perhaps the level of sharpness can be made to appear in the ballpark of the Howtek scans, but the (huge) tradeoff is, of course, noise...

But would this affect your output at 300dpi? I hope you will do some print tests and let us know!

The rope image is going to be better at hiding the noise increase because of the complex, higher frequency textures, but the smooth paper really tells the story, imo.

I hate color-noise personally, it is my enemy, and I think it robs prints of definition even at 300+ dpi, even on matte paper, which goes back to the lack of definition in the file in the first place. Even in the scaled version of your comparison, I can see this effect as a loss of smoothness due to the color-noise related aliasing, and this is exactly what I see on noisy prints to paper. But this is nit-picking. Still...

Having just knocked it, I must reiterate that I am wholly impressed with the level of film scanning that we are now seeing from cheap desktop machines - compared to the last time I worked with desktop scanners for film, we are entering a revolution.

[Peter De Smidt]

Someone better wake Lenny

[Don Hutton]

The operator of those scanners needs to know exactly what he's doing to extract the best out of both of them. I've made a couple of hundred scans with the Epson 4990, with Doug Fisher's mounting station (IMO, an essential accessory with that scanner) and with the Howtek 4500 (the same images - rescanned after I purchased the Howtek). In every single case the Howtek scans are a long way ahead of the scans from the Epson in detail, native sharpness and microcontrast. And it's not only in huge prints that you see the differences - I was working on the attached image yesterday, scanned on the 4500 (shot on 4x5) and had previously scanned it with the 4990 and made a number of prints at different sizes. Even on prints as small as 11x14, there are substantial differences - mostly because the Howtek 4500 extracts all the tiny tonal differences which the Epson 4990 cannot, resulting in increased microcontrast and apparent "texture detail"... On color positive, the drum scan has another huge advantages because Dmax is much, much better than the 4990.

If you want to make a decision on scanners based on a single sample point from an unknown operator, do for it, but I'd strongly suggest that you may well end up with something you don't want or didn't need. I believe that the Howtek 4500 example on that collaboration has been discussed many times with the conclusion being that it was a poor example.

I don't think anyone needs to see another drum scanner/EPson flatbed wankathon - if you think they are remotely comparable, get a sample done of the same image by a reputable professional and make up your own mind.

[Bruce Watson]

There is more to a scan that just simple sharpness. Come on, lets see a show of hands -- how many of you have ever made a photograph that's just about sharpness? Anyone? No? I'd like to have one to put up with the one I have that's only about saturation.

Even if sharpness is all you care about, if you start with better sharpness, you don't have to work so hard to get to the end point. IOW, you are sharpening your consumer flatbed scan a good deal more than you are the drum scan. In addition to the scene detail, you are also sharpening any noise (grain clumps). I can see this "coarsening" in the non-print portion of your newspaper example.

If you are scanning negatives in particular, most drum scanners give you some inherent advantages in image quality. Most of them can apply their entire digital range to the exact density range you specify for the film when you set your black and white points in the scanning software. I've never seen this in a consumer flatbed. What this means is smoother tones and tonal transitions in the scan file and of course in the print (which is what counts).

Just due to the way drum scanners light the film they have certain inherent advantages. All the flatbeds I've seen light the entire film at once. This means that light scatter is a problem, particularly in the less dense areas of the film. I'm always impressed at how well a drum scanner scans the shadow detail in B&W, where the flatbeds I've used left a "veil" over the shadow details.

To get the most out of any scanner however, you have to spend some time and climb the learning curves. A good operator can make a good scan from a consumer flatbed, while a bad operator can make a bad scan from a drum scanner.

The bottom line here is always the prints. If you are happy with your prints, no matter how you get there, then good on ya.

[Ben Syverson]

Perhaps the level of sharpness can be made to appear in the ballpark of the Howtek scans, but the (huge) tradeoff is, of course, noise...

There is more noise in the Epson scans after sharpening, but keep in mind that I'm applying the sharpening to 8-bit JPEGs that were compressed for the web.

The odds are that a nice 16-bit scan from the Epson would clean up the majority of that noise. Even if it didn't, there is a lot of really good noise reduction software out there now.

But even with the noise level as it is, I think I'd be hard pressed to tell the difference once it was printed at 300 DPI. The slight dithering of the inkjet spray would probably mask that difference. And the lower resolution of a Lambda / C-print would obscure some noise and fine detail as well.

[Ben Syverson]

I will indeed get a drum scan of one of my images done soon, so I can make a better comparison. Maybe I'll post again after I do.

[Lenny Eiger]

Someone better wake Lenny

Thanks, Peter, I'm here. And I am truly glad the message is delivered with humor. We all need a little these days.

When it comes down to it, I would echo what Don and Bruce said...

I have been testing film for the past three weeks. I don't have full conclusions yet. Many things look good in N light, out in the sun... However, I will say that the 4x5 looks very good. But it isn't an 8x10. The 8x10 has a quality that feels 3-dimensional. I'd rather carry the 4x5... but the 8x10 is clearly superior...

The same is true of drum scanners vs flatbeds (or at least consumer-prosumer level flatbeds, I haven't done my own testing of the top models). The flatbeds leave me flat...

On occasion, things can come together and produce a good result with just about anything. I strive to be able to do it time after time, and to do that I need good equipment, cameras, lenses, scanners, printers and good ink. And I have to know what I am doing with it all... and it keeps changing. A drum scanner takes one variable out of the puzzle of it all, not unlike a great lens... and that's comforting to me.

Lenny

[Ben Syverson]

Lenny, that makes plenty of sense!