How to deal with negative curve

[DanielJohannes]

Hi all,

Recently I've been getting inconsistent scans due to horizontal curvature on my negatives. For some reason this is most noticeable with negatives that I have developed myself. The problem presents itself in the form of:

1. A line running down the middle of photographs. This almost has the appearance of oil on water - the light is obviously being refracted in a way that makes it noticeable once scanned. I'm assuming this is because the curvature compresses the film base most strongly at this point.

2. Noticeable distortion of photographs. This occurs only in extreme cases, but renders the scan unusable since objects at the top or bottom of the negative are severely compressed.

Is anyone aware of a way to prevent this? I dry my negatives by hanging them on a clothes line, and weigh them down with a peg attached to the bottom. I'm using an Epson V600 scanner.

 

[Timmyjoe]

I don't know anything about the Epson V600 scanner, but I know from my experiences that the B&W negatives I process, curve more than usual in the winter because the house is much more dry. I find, when drying the negatives, if I run a vaporizer in the same room as the negs are hanging, they curve much less, and I find if I run the same vaporizer in the room where I am scanning the negs, they curve much less.

I don't recommend this, but sometimes when I have a badly curved negative, I'll pass it back and forth thru the steam coming out of the vaporizer, and it flattens right out. (It will "re-Curve" after it gets really dried out again, but I can usually get it scanned before then).

The other thing I do in the summer, when using film that is notoriously curved, is place the dried negatives under a very heavy stack of photo books I have on a shelf, and let them sit there for a few days. This flattens them out pretty well.

Again, I don't know your scanner,. but that first thing you list, the line running down the middle of the images, not sure that would be "curved negative" related.

Hope that helps.

Best,
-Tim

 

[grouchos_tash]

The 'oil on water' on the centre of the image is where the negative has touched the glass of the scanner, look up 'Newton rings' 🙂

Different brands of film are more curved than others. Try turning the negative the 'wrong' way up and flip the image in pp

 

[jbhthescots]

This is why we own many large, coffee-table photography books!

 

[sreed2006]

I have used Epson flat bed scanners, and with curved film that just won't lay flat, the best and only solution is to use a glass on top of the negative to flatten it. You can get the glass here:

http://www.betterscanning.com/scanning/models/v600.html

It takes more work to situate the negative in the holder, but the results are worth it.

 

[ruby.monkey]

Another possibility is Lomography's DigitaLIZA negative holder (available for 35mm and 120 film). While they're mainly intended for scanning panoramic photos, they are able to flattening out and holding single strips of film.

I've used the 35mm holder to tame Tri-X in the past. Not the fastest tool but (if you can find one) a cheap and effective scanning aid.

 

[Sykomor]

I usually roll the negative strips emulsion side out and keep them there a few hours before scanning.

 

[Arbitrarium]

Yeah the oil on water thing is from the neg touching the scanner glass. Just scan them upside down and flip them in Photoshop/whatever

 

[rfaspen]

Assuming its Newton rings, the solution offered by Arbitrarium is a good one.

But, I have a flat bed scanner that I rarely use (V500), partly because of difficulty holding film (in particular MF film). The neg holders that came with the thing appear to hold film about 1.5mm above the scanner glass, and I wish I could instead just lay my film directly on the glass (and flatten it out in the process).

My question to all: Can you (do you?) place a piece of anti-Newton glass directly on the scanner glass and then place your neg on that (i.e., the anti-Newton glass is approximately 1.5mm thick) and another piece of glass on top? I know I'm quite ignorant about scanning with the flatbed because I have a dedicated scanner for 35, but I'm stuck in the muck when it comes to MF. I'd shoot more MF if I could achieve decent scans...

 

[mdarnton]

I usually roll the negative strips emulsion side out and keep them there a few hours before scanning.

I have a 100' bulk film can that all film goes into, reverse curled, until I find the time to scan it. That gets it flat long enough for me to scan, then I put it into neg pages. Fortunately, I don't scan for weeks at a time, so this works well, in that I always know what's next to do, also.

 

[grouchos_tash]

This is the bonus (one of) I noticed moving from the Epson 4490 to Plustek; the neg holder has 'bars' between each frame that flattens the film. It works great as long as the spacing on your camera does haha

 

[sepiareverb]

Another bonus of wet printing. I scan my prints.

 

[newsgrunt]

reverse roll the film onto a reel and let stew for a day or so. reverse rolling is rolling onto reel as usual but with emulsion out.

 

[oprahhwinfreyy]

If you don't want to wait for your film to flatten out, get a piece of Anti Newton Ring Glass.

I have an Epson V600 and was fighting this for months before I just smartened up and bought a piece.

I went with the medium format strip size bought on ebay:

https://www.ebay.com/itm/SCAN-TECH-...var=471713992069&_trksid=p2060353.m2749.l2649

I don't scan with a holder so I can get the edges of the roll, so I went with the medium format so I can do both medium format and 35mm since both fit underneath.

I scan with the emulsion side up, and the ANR side of the glass ontop of it. Then I reverse the image back to normal in post.

 

[Arbitrarium]

As an aside, new Kodak Portra dries very flat in my experience. XP2 also dries pretty flat. The majority of the time I shoot on Fuji C200 and that's quite curly, but I just scan upside down, the neg holder flattens it enough to not have any focus issues.

 

[rfaspen]

So with a V600 you can just place the negative on the scanner glass and cover with the ANR glass?

Why do the factory (and aftermarket) negative holders keep the film about 1.5mm above the scanner glass? I have read that the focus of the scanner is why. My V500 leaves me flat (pun intended) with sharpness/resolution of MF negs, I wouldn't dream of trying 35mm with it.

If you don't want to wait for your film to flatten out, get a piece of Anti Newton Ring Glass.

I have an Epson V600 and was fighting this for months before I just smartened up and bought a piece.

I went with the medium format strip size bought on ebay:

https://www.ebay.com/itm/SCAN-TECH-...var=471713992069&_trksid=p2060353.m2749.l2649

I don't scan with a holder so I can get the edges of the roll, so I went with the medium format so I can do both medium format and 35mm since both fit underneath.

I scan with the emulsion side up, and the ANR side of the glass ontop of it. Then I reverse the image back to normal in post.

 

[charjohncarter]

I use the Betterscan 35mm ANG on the Epson 35mm holders, but I do not (when I have horizontal curved negatives) have emulsion facing up. The glass flattens the curve, but you do have to 'Flip Horizontally' in post processing.

 

[jbharrill1]

What I find works best for me is right after I cut my negatives and put them in archival sleeves I will roll the sleeve into a tube that is rolled in the opposite direction that the negs want to roll. I will rubber band them and keep them rolled up for about 12-24 hours. After you unroll them they should be completely flat.

Also I'm not sure if it has been mentioned above but check out www.betterscanning.com , they have some of the anti newton ring glass cut specifically for different scanners/negative holders.

 

[Steve M.]

I got rid of the neg holders on my Epson flatbed back when I was scanning film. They cropped some of the image, and the negs didn't always lay flat. As mentioned, the scanners do seem to focus a little beyond the top glass because they are set for neg holders, so I came up w/ a DIY solution.

I made a couple of marks on the glass w/ a felt tip pen where my 35mm and 120 negs would usually be scanned, and then ran two pieces of masking tape on the marks the length of my neg strips. Think of a train track w/o the lumber in the middle. Then I laid more strips of masking tape on top of that until I had a nicely raised surface. The neg strip was placed on my two masking tape rails, and I used a piece of tape to attach one side to my tape rail. Then I pulled the neg tightly and taped it down on top of the other tape rail. This gave a really flat negative that scanned beautifully.

Yeah, it was a little fiddley, but after a while you could tape the strips down quickly, and it was easy to release them for the next strips. The only down side was that for different film formats you had to pull the tape rails off the glass from the last format, but I always scanned batches of negs of the same format at one time, so it was no big deal. My scans using this technique were much sharper than when I used the Epson film holders. In fact, with some post processing I could get scans that were virtually identical to scans from my Nikon V ED film scanner, except that my Epson could only go to 2450 resolution and the Nikon could do 4000, so the Nikon scans were bigger but not a lot better, if at all. I was able to make 12X18 prints from good 35mm negs w/ this setup, and the 120 negs REALLY looked great.