Flattening Film

*clawhammer* · 10-04-2008, 04:55 PM

I really enjoy shooting slide film. For handling and speed-of-scanning reasons, I don't have it mounted when I process it. However, this leads to a problem- oft times I get film that has a bend in it that runs the length of the film (ie, the middle of the film strip is higher than the edges). Thus, when I scan it in my Epson 4990, it isn't completely flat, and I think I'm seeing visible sharpness loss because of this.

My question, then, is this: does anybody know any good ways to flatten the film? I know wet mounting it would provide for maximum flatness, but I don't have the equipment to do that.

Sluggo · 10-04-2008, 06:00 PM

Not sure I see a big difference in sharpness, but my concern is preventing Newton rings in my scans, which can be a major annoyance. So I've started to get in the habit of very gently reverse-rolling film, emulsion side out, and putting it back in the plastic film cannister for a couple of hours after it has hung out to dry. I'm talking about b/w film developed at home. The film comes back out of there not truly flat, but flat from side to side, which is all that matters. The curvature in the other direction is taken care of by the way the tray clips the film down (I have a 4490, and assume you are using the same tray).

Just one idea, there are many others. It's possible to scratch the emulsion doing it this way if you're not careful. The method I've seen described more often is to stack heavy books on your film. That hasn't worked as well for me.

*pingflood* · 10-04-2008, 06:02 PM

I just stick mine in some negative sleeves and pile books on top for a week or so. Perfectly flat negs.

*Clicker* · 10-04-2008, 06:59 PM

Mis read that sorry, why don't you just sleeve them as "cut" strips and put them in a folder, that usually keeps them flat.

felix68 · 10-04-2008, 07:25 PM

Flatbed scanners have at least an inch of DOF so issues with small film curvature should not be a problem. Are you sure that your settings are correct and that you scanner is not out of calibration somehow? I have scanned some very "cupped" negs and they have always come out sharp from edge to edge. I am using a Epson 3490.

*pingflood* · 10-04-2008, 07:39 PM

Originally Posted by felix68

Flatbed scanners have at least an inch of DOF so issues with small film curvature should not be a problem. Are you sure that your settings are correct and that you scanner is not out of calibration somehow? I have scanned some very "cupped" negs and they have always come out sharp from edge to edge. I am using a Epson 3490.

No, they do not. There's a reason height adjustable film holders are doing well, and that is due to flatbed scanners producing crappy results being off even by a tiny bit.

*geauxpez* · 10-04-2008, 08:15 PM

I second Pingflood's advice. Sleeve 'em & press 'em.

*clawhammer* · 10-04-2008, 10:19 PM

Sounds like that encyclopedia set that cost so much money 25 years ago will finally come in handy

I've got them sleeved already, so I guess now it's just time to apply pressure.

PS: do you think a hot iron would speed up the process?

Nesster · 10-05-2008, 04:47 AM

Originally Posted by clawhammer

PS: do you think a hot iron would speed up the process?

Heavens to Mercatroid! Ya really think?

For the flatness issue, there of course is a $$ solution:
Custom film holders and Anti Newton Glass

Mike Cash · 10-05-2008, 05:07 AM

Originally Posted by clawhammer

Sounds like that encyclopedia set that cost so much money 25 years ago will finally come in handy I've got them sleeved already, so I guess now it's just time to apply pressure.

PS: do you think a hot iron would speed up the process?

Old-school can be taken too far. A hot iron.....for goodness' sake.

If you want to speed up the process pop them in the microwave.

felix68 · 10-05-2008, 11:56 PM

Originally Posted by pingflood

No, they do not. There's a reason height adjustable film holders are doing well, and that is due to flatbed scanners producing crappy results being off even by a tiny bit.

A few "pictures" are worth a few 1,000 words...

Use a flatbed scanner as a camera - Photo Galaxy

Don't make absolute statements if you don't have all of the facts. His scanner may well have no depth of field but that is no the case for all scanners. I have never had to worry about my negs being slightly cupped in the holder and his scanner, I believe, is a better model. Furthermore, the supplied neg holder for my scanner does not keep the negs flat to the glass.
Granted, some really low end scanners do have to have items right on the glass to get any reasonable results but I don't think this is the case here.
Do you have an Epson Perfection line scanner, pingflood?