Dmax and Density range

[Bruce M. Herman]

Knowing that there will be diverse opinions and hoping that this will become overly contentious...

What is considered to be an adequate Dmax and Density range for scanning color transparencies? Would 3.9 and 3.7 (respectively) be appropriate?

Now I know that you'll ask what I mean by appropriate. In this case, I'll be "backing up" my film in addition to scanning it for prints.

Thanks.

[Bruce Watson]

Knowing that there will be diverse opinions and hoping that this will become overly contentious...

What is considered to be an adequate Dmax and Density range for scanning color transparencies? Would 3.9 and 3.7 (respectively) be appropriate?

Now I know that you'll ask what I mean by appropriate. In this case, I'll be "backing up" my film in addition to scanning it for prints.

Thanks.

I wouldn't believe much of anything that a manufacturer says about a scanner's Dmax capabilities. They all seem bent on hype without any supporting evidence to back up their claims.

There is / used to be a Kodak Step Tablet that went to 3.6 which is the highest I've heard of. The closest I've been able to find recently is the Kodak 1A Step Tablet which goes to a density of 3.05. The way to find out what a scanner is actually capable of (as opposed to the marketing hype) is to scan such a step tablet and see how far up the density scale you can actually resolve.

When I read numbers above 3.6 I have to wonder what data they have to back up that claim.

To the best of my knowledge tranny films top out around 3.6 or so.

The only reliable way to know if a scanner is adequate for your needs is to scan some of your trannies on said scanner. If the shadows in the scan file have detail where the tranny has detail you've got a winner. Otherwise, the shadows in the scan file will fade to black. If the scan file shows enough shadow detail to satisfy you even if some are black, you also have a winner. Otherwise, keep looking.

[sanking]

Bruce,

One could lap two step tablets to create more density if needed. The commercial step wedges (Stouffer and Kodak) that I have only go up to about log 3.35-45.

Sandy King

I wouldn't believe much of anything that a manufacturer says about a scanner's Dmax capabilities. They all seem bent on hype without any supporting evidence to back up their claims.

There is / used to be a Kodak Step Tablet that went to 3.6 which is the highest I've heard of. The closest I've been able to find recently is the Kodak 1A Step Tablet which goes to a density of 3.05. The way to find out what a scanner is actually capable of (as opposed to the marketing hype) is to scan such a step tablet and see how far up the density scale you can actually resolve.

When I read numbers above 3.6 I have to wonder what data they have to back up that claim.

To the best of my knowledge tranny films top out around 3.6 or so.

The only reliable way to know if a scanner is adequate for your needs is to scan some of your trannies on said scanner. If the shadows in the scan file have detail where the tranny has detail you've got a winner. Otherwise, the shadows in the scan file will fade to black. If the scan file shows enough shadow detail to satisfy you even if some are black, you also have a winner. Otherwise, keep looking.

[Bruce Watson]

Bruce,

One could lap two step tablets to create more density if needed. The commercial step wedges (Stouffer and Kodak) that I have only go up to about log 3.35-45.

Sandy King

You could, but then you'd be looking though an extra film base. Kodak *did* make a 3.6 didn't they? Or is that a memory error on my part?

[Bruce M. Herman]

Hmm, a typo in my original post: should have said "hoping that this will not become overly contentious."

Thanks, Bruce and Sandy. I was hoping that the specifications of the professional scanners (Creo, Heidelberg, etc.) would have some empirical basis. I guess Madison Avenue permeates business at all levels.