Scanning 4x5s

[nathbdp]

Hello,

 

I'm planning to upgrade to a 4x5 View Camera system. My current

(35mm) system utilizes a digital workflow where the film is scanned

(with Nikon Coolscan), edited in Photoshop, and then printed with an

Epson.

 

My question is, what are the various methods of scanning 4x5 negs and

transparencies for a digital output?

 

Thanks

[leonard_evens]

I have an Epson 3200 which I use for scanning medium format and 4 x 5. The 3200 is only slightly better than the Epson 2450, and I've posted some examples, including one 4 x 5 example, for the 2450 at

 

math.northwestern.edu/~len/photos/pages/e2450.html

 

I estimate that the 3200 can resolve about 30 lp/mm (which is about half of its theoretical maximum based on a scanning resolution of 3200 ppi.) That means it ought to suffice for up to 5-6 X enlargement if viewers are going to get close to the print, and more if they stay a normal viewing distance away. You can also improve the results by careful modest sharpening, probably not nearly what you would use for 35 mmm.

 

The Epson doesn't allow for elimination of dust and scratches during scanning, but I manage just by normal dust control measures.

 

You will need a fast CPU and a lot of memory to handle the large files you will get. I have a 1.4 GHz Athlon and 1.5 Gb of ram.

 

I use Vuescan to scan my negatives. I prefer to scan negatives because one has more exposure latitude in the first place and the resulting dynamic range can be handled by a reasonable scanner. If you insist on scanning slides and you are not careful about exposure, you could have some problems with the Epson's dmax of 3.4. But I have managed to scan slides with it and get acceptable results.

 

There are higher priced flatbed scanners in the range $1,000-2,000, but you mainly pay for being able to scan larger transparencies than 4 x 5. They may have better optics but they tend to scan at lower scanning resolutions like 1600ppi.

 

If you want to definitely do better than the Epson with 4 x 5, I think you may have to go to the Imacon, which costs more than $11,000.

 

I've been pleased with the results I get from my Epson. If you want further details, let me know.

[mark_messerly1]

The HP Scanjet 7400C is what I use. I did not check others extensively, so here are some annoyances with this pup that may steer you toward more research. 1. No specific 4x5 neg carrier, you'll have to make one or suffer the (fig) Newton rings. 2. The interface is wretched. 3. The auto exposure values are frequently wretched. Sometimes I select a small area to get the exposure close, then reselect area and work with it in Photoshop. The reason I got it at the time was price... the ones I wanted were much more costly. Now I know why! Good luck!

[nathbdp]

Thanks for the replies. Very informative and helpful link Leonard. They look very good.

 

I will probably scan a lot of slides.

 

Leonard posted:

>>If you insist on scanning slides and you are not careful about >>exposure, you could have some problems with the Epson's dmax of >>3.4. But I have managed to scan slides with it and get acceptable >>results.

 

I have heard the term "exposure" used for the scanning process when using flat-beds. In this context do you mean exposure of the slide or the settings on the scanner? What does the dmax control/mean?

 

Thanks

[david_f._stein]

The old, slow, noisy, SCSI based Linocolor Saphir 2 and UMax Powerlook III are still

excellent choices for 4x5 and larger negs, not to mention that you can set up on the

8x10 transparency bed for more than one neg at a time. Although these are fixed

foxus scanners, the optics are excellent and they are clearly professional quality

machines. In favor of the Epson design, the exposure is similar to a diffused or cold

light source and it is much easier to avoid Newton's rings. When we printed directly by

enlarger from neg to photo paper, we gave up many choices/possibilities; with

scanning and digital printing, you also "loose" some information, possibilities but you

gain many. There is no right or wrong-any print is an interpretation of the world.

GODO LUCK...

[leonard_evens]

About exposure:

 

I am referring to exposure in the camera when you take the picture. Generally with slides, you have very little latitude in exposure anyway, so you try to get it dead on.

 

There are several reasons for that.

 

One is that you won't separate high values as well because they may appear on the shoulder of the characteristic curve of the film. Another is that the slide will tend to look washed out if viewed by normally by transmitted light if overexposed. You can adjust for that in a photoeditor if you scan, but the total range of densities from deepest shadow to lightest highlight could end up being greater than what the scanner can handle. That is because, since, unlike negative film, reversal film is designed for direct viewing, so it inherently has a large density range, which overexposure can increase further. With a high range scanner like an Imacon, that is not likely to be a problem, but with the Epson 3200---dmax 3.4---it could be.

 

Ansel Adams, in The Negative, advises slight underexposure for slide film as preferable to slight overexposure. 35 mm photographers usually bracket extensively in order to deal with such issues, but with 4 x 5 one may not want to do that. First there is the cost of the film, but more important I find I am often right at the limits of what I want to do in terms of f-stop and shutter speed. In order to get adequate depth of field, large format photographers often stop fairly far down, so they tend to use relatively long exposures. For natural scenes and most architecture you seldom will be shooting faster than 1/30, and you may have to go below that. Rather than wasting film and taking three or four shots half a stop apart, it makes sense to get the exposure right to start with so that one or two shots will suffice. The best way to do this is to use a spot meter and a modified version of Ansel Adams Zone System to determine exposure. When using that system with negative film, one usually chooses the exposure based on the important shadows, which may lead to overexposure of the highlights for a contrasty scene. One deals with that either by under development of the negative for b/w or if you scan by contrast control in the photoeditor. On the other hand, with reversal films, one should choose the exposure based on the important highlights, and so for a contrasty scene one may have to sacrifice the shadows. Before scanning, you were usually limited with reveral film to scenes of relatively low contrast for that reason. If you scan, you can handle high contrast scenes by adjustments in the photoeditor, but you may run into problems if you exceed the dmax of the scanner.

 

Negative film need not have a large density range because it is not meant to be viewed directly, so any decent scanner will be able to handle it. There are of course other arguments for using slide film, but I think on analysis they are not that convincing.

[mark_messerly1]

The July/August issue of 'View Camera' has an article about this topic. George DeWolfe (The Senior Editor) examines some scanners in the $700 - $1500 dollar range with some great examples and advice.

[leonard_evens]

DeWolfe article:

 

He includes the Epson 3200 which is $400. You can buy the "Pro" version for a higher price if you want the additional software it includes, but it is not absolutely necessary.

 

He also has a section on 8 bit vs 16 bit, and its relation to color depth, which I found confusing. This prompted a long discussion in comp.periphs.scanners which I started. It doesn't really matter because all the scanners one is likely to consider do 16 bits per channel. In any event, this is a side issue, and the real issue is the largest range of densities in the source that the scanner can handle. For negative film, this is not really an issue, but it can be for slide film as I've explained elsewhere.

 

DeWolfe says he relies almost entirely on Silverfast software for scanning, but many of us prefer Vuescan.