Testing film speeds for scanning

[menglert]

Hello,

Would testing my films true speed differ any in the process if I were only planning to scan the negatives?

-Martin

 

[Ted Harris]

No is the simple answer.

I think the question you mean to ask is whether or not you should expose your film the same for scanning as for other purposes. Some will tell you that it is easier to scan a slightly thin negative or slightlyoverexposed chrome but I don't necessarily go along with that. Expose as you normallywould and you should have no trouble with your scanning.

 

[menglert]

No is the simple answer.

I think the question you mean to ask is whether or not you should expose your film the same for scanning as for other purposes. Some will tell you that it is easier to scan a slightly thin negative or slightlyoverexposed chrome but I don't necessarily go along with that. Expose as you normallywould and you should have no trouble with your scanning.

Thanks for the prompt answer.

-Martin

 

[artonic]

For positive film, overexpose and pull-process by 1/3 to 1/2 stop - depending on the subject - produces a little less contrast, making it easier for my scanner (Nikon) to capture tones at the extremes.

 

[Bruce Watson]

Would testing my films true speed differ any in the process if I were only planning to scan the negatives?

Your film's speed? No. That is dependent only on the film and your processing of the film. You can (and probably should) test for this using any of the popular EI testing methods.

If your question is, as Ted suspects, whether you should alter your processing to optimize for scanning, I would offer this observation:

For just about any photographic process you can name, you'll get optimim results from film that has the least density that still gives you the results you seek.

Scanning isn't much different from platinum printing in this respect. Negatives optimized for these two processes would have very different Dmaxes, and therefore very different contrast indices, however.

 

[XRe]

In a related subject - how would one evaluate personal EI in a "scan only" environment - where you weren't going to print to traditional grade 2 paper?? Is it just hit or miss, or is there a reasonable process to follow?

I have to apologize for what might be an obvious question - I've been exclusively digital for four years, now, and didn't do a whole lot of B&W work before I went digital... In the past, I hadn't gotten to the point where I actually evaluated my process for a personal EI - the manufacturer's suggested times seemed to work fine, esp. w/ a 1/3-1/2 stop "overexposure".

Weaving my way back into film - but I have no wet darkroom to work with, just tanks to develop film... but I'll be doing 120/220 and 4x5 stuff (instead of the 35mm I did in the past). Lots to remember and learn

Dave

 

[sanking]

For just about any photographic process you can name, you'll get optimim results from film that has the least density that still gives you the results you seek.

This is not true IMHO if you are scanning stained negatives.

Yesterday I made a horrendous mistake in developing some 5X7 negatives in a staining developer. The result left me with a B+F density of log 1.65 and a DMax of around log 3.6 (UV reading). I was very concerend that these negatives would not scan well, but in fact they scanned exceptionally well, with high accutance and very tight grain. They are in fact some oif the best scans I have ever made friom 5X7 film.

Sandy King

 

[SPS731]

This is not true IMHO if you are scanning stained negatives.

Yesterday I made a horrendous mistake in developing some 5X7 negatives in a staining developer. The result left me with a B+F density of log 1.65 and a DMax of around log 3.6 (UV reading). I was very concerend that these negatives would not scan well, but in fact they scanned exceptionally well, with high accutance and very tight grain. They are in fact some oif the best scans I have ever made friom 5X7 film.

Sandy King

Sandy,

Do stained negatives show the same benefits with digital scanning and printing as they do in traditional silver gelatin printing?

Also, are you planning to start using denser negatives for all your scanning now that you have experienced these resuls?

Thanks.

 

[sanking]

Sandy,

Do stained negatives show the same benefits with digital scanning and printing as they do in traditional silver gelatin printing?

Also, are you planning to start using denser negatives for all your scanning now that you have experienced these resuls?

Thanks.

Scanning stained negatives gives as many benefits, perhaps even more, than with traditional silver printing. If possible I would recommend scanning in RGB and then examining the grain and tonal scale of each color. You may get better results by dropping one or two of the channels.

As for the use of denser negatives, I am backing into this since all of my negatives were originally developed to a fairly high density range (log 1.8 or so) for printing with alternative processes. However, I don't believe that I would recommend that you develop for that long a DR unless you specifically want the negatives for alternative printing.

For negatives meant for silver printing and scanning you can get almost grain free prints from medium format up to about 16X20 with TMAX-100 or Fuji Acros developed in a staining developer.

Sandy King

 

[Videbaek]

I've had the same excellent results noted above when scanning negatives developed in pyro/staining developers. The scans somehow just seem to contain more information, and look great (vs. non-staining developers). This is especially true up in the very high tones, which retain information -- obviously the stain helps the scanner "grab" the information that is there. I use a fairly expensive, good, semi-pro Canon film scanner. When it comes to scanning, though, the absolute best quality comes from a drum scanner in the hands of a skilled operator. Sigh, the expense: here in Helsinki, about 40 euros per 6 x 6 negative of resolution/size equalling A3 size. I rarely splurge, but love the quality when I do.