Coolscan V ED - how to ensure film planarity

[Arjay]

Recently, I have done a lot of scans of BW negatives on my Coolscan V ED, equipped with the SA-21 strip film adapter (the one that can pull in an entire film strip and automatically advance from one frame to the next).

I found a slight defocusing near the edge of the frame in almost all scans. Nothing too serious, as it is only visible in uncropped images at high magnification, and mostly, this doesn't affect any important parts of the negative.

However, I am still looking for a way to get tack-sharp scans from edge to edge. What can I do to remedy this problem?

My negative strips show fairly strong bending perpendicular to the length of the film. Would I need to store them differently to make them flatter, or doesn't that make any diffrence in scanning?

Or, do you have other suggestions to solve the problem?

 

[benno]

Forgive the stupid question, but are you certain it's not your lens?

 

[sahe69]

Buy the Nikon FH-3 strip film holder. That'll flatten out curved negatives although it makes the scanning process slower.

It also helps if you keep the neg strips under a heavy book for a week or so (inside archival sheets of course).

 

[Arjay]

Forgive the stupid question, but are you certain it's not your lens?

Yes - the negatives look perfect on my light table under a strong magnifying lens.

Buy the Nikon FH-3 strip film holder. That'll flatten out curved negatives although it makes the scanning process slower.

It also helps if you keep the neg strips under a heavy book for a week or so (inside archival sheets of course).

Thank you for your suggestion. That sure looks like a viable solution to my problem.

 

[JamSee]

Arjay, I have the exact same problem on my coolscan IV with SA-21. 2 or 3 percent on each side of the frame are noticeably blurred- You are not alone!

 

[not_in_good_order]

I noticed a similar issue when scanning 400TX with my Coolscan 5000ED (basically the same scanner as yours). The only solution I found has been to put the negatives in sleeves and apply pressure to flatten them out. It takes a bit of patience, but the lens in these scanners only has so much depth of field.

 

[not_in_good_order]

I've also noticed that strongly curled film can still bulge a bit even with the FH-3, though using that device helps quite a bit. The FH-3 is essential to scanning frames at the end of a strip. The edge of a frame at the end of a strip will never be completely sharp without using it.