Scanned film & exposure accuracy of highlights

[Jon Warwick]

I often find there are scenes whereby I place the shadow detail on Zone III, but the brightest area where I want texture in the scene can sometimes fall into Zone IX (or almost into Zone X).

I then get the film processed at normal. The negative seems to record the highlights' data OK, although they look a somewhat blown-out on an "unadjusted" contact sheet.

I typically get my negatives drum-scanned and digital prints made.

My question is .... Would it really make much difference if I had the film developed at N-1 or N-2 for the above scenario to compress the range of shadow --> highlights into a III --> VIII range?

Importantly -- am I losing resolution or other "image quality" by not getting the highlights down to the ideal Zone VIII? Or with the latitude of modern film (I shoot ACROS 100), and with the fact that I always get the negatives drum-scanned, would I see no difference if I did N-1 or N-2 vs. my current method of "normal development"?

Many thanks.

[Peter De Smidt]

With a consumer scanner, there might be a advantage with less development, but I doubt that there'd be any with the drum scans.

[Joanna Carter]

I often find there are scenes whereby I place the shadow detail on Zone III, but the brightest area where I want texture in the scene can sometimes fall into Zone IX (or almost into Zone X).

I then get the film processed at normal. The negative seems to record the highlights' data OK, although they look a somewhat blown-out on an "unadjusted" contact sheet.

I typically get my negatives drum-scanned and digital prints made.

My question is .... Would it really make much difference if I had the film developed at N-1 or N-2 for the above scenario to compress the range of shadow --> highlights into a III --> VIII range?

Importantly -- am I losing resolution or other "image quality" by not getting the highlights down to the ideal Zone VIII? Or with the latitude of modern film (I shoot ACROS 100), and with the fact that I always get the negatives drum-scanned, would I see no difference if I did N-1 or N-2 vs. my current method of "normal development"?

We have done some comparisons of N- development over standard, when scanning as opposed to wet printing.

We have found that, even flatbed scanners, can happily resolve a wide range of exposure detail. th important factor being to ensure that your highlights are as well exposed as possible, as D-Max limitations can cause loss here rather than in the shadows.

Apart from that, I have found that the range of tones that can be scanned can easily exceed 10 zones without loss. I once had a neg, (accidentally) underexposed by over 4 stops and, although the finished scan wasn't good enough for printing, their was shadow detail, some 13 zones from some highlight detail

[Bruce Watson]

I often find there are scenes whereby I place the shadow detail on Zone III, but the brightest area where I want texture in the scene can sometimes fall into Zone IX (or almost into Zone X).

I then get the film processed at normal. The negative seems to record the highlights' data OK, although they look a somewhat blown-out on an "unadjusted" contact sheet.

I typically get my negatives drum-scanned and digital prints made.

My question is .... Would it really make much difference if I had the film developed at N-1 or N-2 for the above scenario to compress the range of shadow --> highlights into a III --> VIII range?

Importantly -- am I losing resolution or other "image quality" by not getting the highlights down to the ideal Zone VIII? Or with the latitude of modern film (I shoot ACROS 100), and with the fact that I always get the negatives drum-scanned, would I see no difference if I did N-1 or N-2 vs. my current method of "normal development"?

I'm a drum scanner owner/operator. I scan my own 4x5 B&W (mostly Tri-X and now 400TMax) and film for clients too. I've never had a problem reading through any B&W negative including some I've brutally abused in testing (Tri-x with a Zone VIII density of 2.5 is seriously ugly with strange artifacts, but that's another story). Suffice it to say that if it's on the film I can read it.

That said, drum scanners are susceptible to Callier Effect just like conventional darkroom enlargers. And Callier Effect isn't linear across the film, it depends on density. The greater the density, the greater the Callier Effect. What you'll see in the scan file is just what you are describing. It "feels" like the highlights are compressed. In fact what's happening is that the local contrast in the highlights is reduced due to the light scatter from the increased metallic silver in the highlights -- classic Callier Effect. This can be made worse by a film that shoulders early in the characteristic curve. You can of course recover from this using Photoshop curves to decompress your highlights.

So, what to do? What I tell my clients is simply this. If you are ever going to use the negatives in the darkroom, you should optimize for the darkroom. They will scan just fine.

If on the other hand you are sure that you'll only scan, then you should optimize for scanning. Nailing the optimization will of course depend on your workflow and your scanner. For me, with my film, my process, and my scanner, I found that I get optimum results from a Zone VIII density of around 1.0, or about N-1 development. This scans beautifully with hardly a trace of highlight compression due to Callier Effect. It would however be sufficiently thin that it would be a PITA to print in the darkroom.

I apply this reduced density development time across all my film. Unlike full Zone System work, my max density varies from sheet to sheet, just like you'd get with roll film. So I'm doing what roll film users have to do, I'm exposing for the shadows and letting the highlights fall where they may. But I'm reducing all highlights somewhat. So on "normal contrast" and below scenes I get great scans with no noticeable highlight compression due to Callier Effect. On "high contrast" scenes I also get great scans with just a bit of highlight compression which is easily corrected.

Of course how I handle it is not necessarily how anyone else should handle it. But it's a way, and it works for me. Clearly YMMV.

[Lenny Eiger]

Importantly -- am I losing resolution or other "image quality" by not getting the highlights down to the ideal Zone VIII? Or with the latitude of modern film (I shoot ACROS 100), and with the fact that I always get the negatives drum-scanned, would I see no difference if I did N-1 or N-2 vs. my current method of "normal development"?

Many thanks.

I would echo what the others have said. (I drum scan for myself and others as well.) I have scanned film that is bulletproof.

There are two things I would add. The first is you talk about what is "ideal" for Zone 8 - ideal for what? Darkroom paper? Scanning? Hmmm, I don't think anyone has identified what this is - or there are at least a dozen ideas about what the appropriate density is for scanning. The clear answer for me has more to do with relative contrast over the entire range of tones, and separating out the midtones enough for modern film, than any specific "top-end" density.

The second thing I would add is that there are drum scan services at labs and other inexpensive routes that just throw the film on the drum and "do it". There are a lot of choices in this process, and every professional scanner will tell you that a lot depends on the operator. When you are looking for quality, which your post certainly implies, then you have two choices. You can work with a smaller scanner operator, who will listen to your concerns and scan the images the way you want them scanned, or you can get your own drum scanner.

Lenny