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View Full Version : Advice sought on Epson V 750 vs Capturing image with my 5D and lightbox



Serge S
25-Jul-2012, 09:46
Hi,

My old Linotype-Hell Saphir Ultra 2 scanner is malfunctioning (banding) and I'm looking to replace it. I am considering the V 750 Epson as a replacement so that I can do 6x7 & 4x5 scans. Just for the heck of it I tried shooting the negatives (HP5 & Portra 160) on a lightbox with my 5D (original version) and a 50 macro. The results were better than the scanner at least at first blush. The scanner looks like it may pull more detail after an unsharp mask as been applied and the 5D lightbox combo are sharper strait out of the camera.

I am intrigued by the speed and the quickness of the lightbox and camera set up. My old scanner is glacial. Do you think it's worth persuing? ( I would need to invest in a copy stand & better lightbox) or am I better off just getting the Epson flatbed? One thing I like about the flatbed set up is that it can convert color negs via software, I had a hard time doing that in curves in Photoshop with my lightbox shot.

I think I'll try a couple of prints today to see how the different approaches result in a finished product.

Thanks,

Serge

PS I've attached the scanner & 5D sample for reference

Kirk Gittings
25-Jul-2012, 10:36
Serge, We have looooooong threads on this in the DIY section. Many members have been exploring this idea for awhile. There are many issues involved. The threads all start with the title DSLR Scanner:....

Serge S
25-Jul-2012, 10:41
Serge, We have looooooong threads on this in the DIY section. Many members have been exploring this idea for awhile. There are many issues involved.

Thanks Kirk. I'll take a look. It sounds like there's no right answer:)

chuck94022
4-Aug-2012, 02:59
While there are long threads on it, I'll comment... When my Epson went into the shop, I did quick proofing scans exactly as you describe - hand held, film on the light table, Nikon D200 as my "scanner". Worked just fine for proofing, was quick, and was mostly good enough for web posting of images.

I've also weighed in on discussions on this. But here is my bottom line on a DSLR as an image maker: First, the sensor in the DSLR has a bayer filter. So you are inherently losing some color resolution due to that. There will be interpolation. The Epson reads all color channels at each pixel position. No interpolation.

Also, the DSLR is either going to record 12 or 14 bits. The Epson, 16. 16 bits provides four times the number of discreet values for at each channel than you will get from a 14 bit DSLR (in theory, of course both devices would need to discriminate color differences at their theoretical maximum - that is probably at least a lens issue, if not a lens/electronics issue). Older DSLRs only do 12 bits per channel in raw - the Epson provides 16 times the discrimination in this case, per channel. In theory, this means your Epson will interpret far more subtle tonal differences. In theory. (I have done absolutely no testing to determine whether any of this theory holds in actual practice.)

So, if you are fine with those limits on your scan (assuming they actually manifest in practice), a DSLR is fine. I think the issues would appear when you try to print large, but I've not tried it. If you are only scanning for the web, a DSLR based scan should be much more than adequate for your needs.

Kirk Gittings
4-Aug-2012, 07:43
Older drum and pro flat bed scanners also capture in 12 and 14 bit (Like the 14 bit Creo Eversmart Pro II) yet they can faaaar exceed an Epson in resolution, color, noise etc.

Leigh
4-Aug-2012, 07:53
Scanning a 4x5 @ 2400 dpi yields 115.2 Mp.

Can your 5D do that?

- Leigh

Kirk Gittings
4-Aug-2012, 08:19
Yes-Stitching.

Peter De Smidt
4-Aug-2012, 10:30
Serge, you might try neutralizing the orange mask of your negative with a filter on your light source, perhaps a Rosco "gel" or similar.

chuck94022
6-Aug-2012, 20:56
Yes-Stitching.

But you'll still have a Bayer interpolated result. Perhaps that won't matter if you zoom in deep to the image, and capture that zoomed in image with a DSLR, and stitch. At that point you've just created another scanner, with perhaps a better sensor.

But I think the sense of the conversation was for the more simple document copy model of using a DSLR. At that level, without sophisticated camera movement and stitching, I think things like Bayer interpolation and bit depth matter.

I agree that pro scanners (drum and pro flatbed) will get better color resolution out of their far better sensors, probably even with reduced bit depth. They are getting far better point by point information out of the image. Such is the tradeoff of getting a v750 for home scanning. (In my case, if I feel an image deserves a better scan I get it professionally done. So far my Epson has exceeded my DSLR (D200), but then I just bought a D800, so I might try this again in the future just for grins.)

To the OP: If your only measure of scan quality is sharpness, you might be perfectly happy with the DSLR "scan". But you can get better resolution, and a richer tonal scale, by using the Epson. You do of course need to be sure the film is in the sharpest plane of focus on the Epson, by the way - it does not autofocus, so you have to shim your holder as necessary to correct for focus issues. Once you do this you should be seeing pretty good scans of 4x5.

(Edit: I guess I have one more point: If a DSLR photo of your 4x5 slide is "good enough", why did you bother to take the 4x5 into the field in the first place? Might as well take the DSLR, and save your back...)

Peter De Smidt
6-Aug-2012, 22:44
I've heard a lot of a priori arguments as to why dslr scanning will be worse than other methods. So far, though, the results have been very encouraging. Using something like a three frame stitch of a 4x5 negative should be easy to shoot and combine. As long as that gets you the resolution you need for the size prints that you want to make, it should be a fast and high quality method. When you start to get more frames, resolvable detail does go up, and it's still pretty fast to shoot, but you'll start spending a fair amount of time in stitching software.

chuck94022
6-Aug-2012, 23:12
I've heard a lot of a priori arguments as to why dslr scanning will be worse than other methods. So far, though, the results have been very encouraging. Using something like a three frame stitch of a 4x5 negative should be easy to shoot and combine. As long as that gets you the resolution you need for the size prints that you want to make, it should be a fast and high quality method. When you start to get more frames, resolvable detail does go up, and it's still pretty fast to shoot, but you'll start spending a fair amount of time in stitching software.

I the the fundamental argument against it is that a DSLR does not measure every pixel position with all color channels. It must interpolate. At your chosen output resolution that may be just fine. For web use it will certainly be more than fine. (4x5 is wasted on the web, there, an iPhone is more than enough...)

But if we are talking ultimate resolution, a Bayer interpolated sensor is a compromise.

rdenney
7-Aug-2012, 05:21
I the the fundamental argument against it is that a DSLR does not measure every pixel position with all color channels. It must interpolate. At your chosen output resolution that may be just fine. For web use it will certainly be more than fine. (4x5 is wasted on the web, there, an iPhone is more than enough...)

But if we are talking ultimate resolution, a Bayer interpolated sensor is a compromise.

Well, there really is no such thing as "ultimate" resolution, until the scanner can sharply delineate each grain. That is beyond any current scanner.

It is tempting to focus on one single aspect of any given system, such as the Bayer array, or the anti-aliasing filter, or the dynamic range, or the mechanical imprecision, or the plastic molded lenses in the strip sensor, or the reflections of the platen glass, or the flare caused by the diffusion light source, and on and on.

Really, though, whether something works or not is a system question as much as a technology question. When applying any technology to a particular use case, some aspects of it will be overdesigned for that application, and others will be marginal or inadequate.

Considering the system as a whole, it is possible using a 5D to get better resolution than using an Epson V750. I have proved that. But it is not easy! And it requires working at 1:1 or even 2:1 and then stitching, with excellent glass. The challenge is not to find a camera with sufficient resolution, Bayer array or AA filter notwithstanding. The challenge is an even light source (or even a light source corrected for the lens's falloff), and a stitching capability that is reasonably efficient, particularly for images with large expanses of smooth tones.

And with negative materials, my 5D had more than enough dynamic range to capture the entire range of densities in a black-and-white negative that I processed for optical printing (read: It was on the dense end of what scanners prefer). I'm quite sure it would be more than sufficient for color negatives, too. Color slides should present the greatest challenge there. I have not yet had time to play with my new-to-me Bowens Illumitran, but in the old days I could control contrast reasonably well duping regular color slides onto Ektachrome (using the contrast unit), and even my 5D has several stops more dynamic range than old 35mm Ektachrome.

Making a single photo of a 4x5 film does indeed beg the question of why the digital camera wasn't used in the first place. One reason is that the intended application does not need more resolution, and another is that the films were made before using a digital camera was an option. But I still use 6x7 and 4x5 because it gives me more detail than I can get from my original 5D, and I don't make enough images for film-based costs to exceed what a better digital camera would cost, even if I had the money.

Several years ago, my wife gave me the task of duplicating a photo album that belonged to her father. I started removing the photos one at a time and scanning them in a flatbed. I was spending about a half hour on each picture. The scanner is designed to record all that can be recorded more than it is designed to make a result that looks like a photo. When that little fact occurred to me, I set up my copy stand and made the photos with my Canon 10D and the 50mm macro lens. Since the camera is already configured to make images that look like photographs instead of images that look like scans, I didn't have to make any corrections at all. I finished the album averaging about 60 seconds for each image. The scanner still provided better resolution, but the camera was still good enough to print those dupes out at their original size and be nearly indistinguishable (from an image standpoint) from the originals. In that use case, the scanner was inefficient overkill.

I'm not sure I understood the OP's point clearly enough to know whether he needed something quick and easy where it was not necessary to extract as much detail from the negative as possible, or whether he really believed a 5D dupe of a 4x5 film on a light table was sufficient to get all the detail that is available in a 4x5 film. Generally, a scanner does better at extracting detail because that's what it was designed to do, and a dupe does better at getting the image onto the web (or into a photo album at snapshot size) because that's what it was designed to do. It's possible, as we have proved, to use the digital camera as a scanner, but it is not easy. The purpose of that effort has not been to make it easy, but to have an alternative when scanners are no longer available.

Rick "who really needs a few hours with that Illumitran" Denney

Peter De Smidt
7-Aug-2012, 08:13
Here a dslr scan of a 6x7 Acros negative:
http://i955.photobucket.com/albums/ae37/peterdesmidt/Light_House_2nd_Manual.jpg

Here's a detail from the image:
http://i955.photobucket.com/albums/ae37/peterdesmidt/sc_100.jpg

That looks like pretty good resolution to me.

Here's a detail from a Screen Cezanne scan at 4000 spi:
http://i955.photobucket.com/albums/ae37/peterdesmidt/Lighthouse_Cezanne.jpg

Here's a detail from a scan using a dslr and a 40 year old 55mm nikkor lens:
http://i955.photobucket.com/albums/ae37/peterdesmidt/LightHousePTGui.jpg

Serge S
10-Sep-2012, 14:03
Can someone recommend a good quality lightbox for digital capturing of transparent originals?