Elliptical marks on scans

[k_m20]

<p>Hey guys,</p>

<p>I've recently bought some rodinal and started developing black and white film again. I shot one roll on my Nikon F3HP, and some on my Leica M6. After developing and scanning the film, I've noticed these strange ellipitical marks on some of the photos, like tree circles.</p>

<p>I am developing using Rodinal. I do not notice any spots on the film that correspond with these elliptical marks. There are some water marks on the film (despite my using Ilfotol, water smears and dries on the film). But I used to develop without using any washing agent and never had those marks, so I'm not sure it's water residue. Also it happened with film shot on both cameras so I doubt it's either camera. Is it the scanner? I'm using a Epson V600. Do any of you have experience with these marks?</p>

<p>Thanks<br /><img src="http://s29.postimg.org/84s8u8do7/photoerror2.jpg" alt="" width="790" height="467" /></p>

[cabbiinc]

<p>These are called Newton Rings. It happens when the film touches the glass sometimes. If you don't have a film holder that holds the film off the glass try flipping the film over.</p>

[larrydressler]

<p>Newton rings. The film is touching the glass of the scanner.</p>

[wblynch]

<p>Dan and Larry are correct; flip the film over.</p>

<p>On my flatbed Epson 4490 scanner, if I put the emulsion side down I don't get the rings. If I put the shiny side down I do get them.</p>

<p>I have to flip the images in photoshop but that's easier than trying to fix the rings.</p>

[larrydressler]

<p>OOps it looks like Dan and I had the same idea at the same time. Sorry.</p>

 

[JDMvW]

<p>The engineers among us will want to start here:<br>

http://en.wikipedia.org/wiki/Newton%27s_rings </p>

[k_m20]

<p>Simple enough. Thanks a lot guys!</p>

[Ed_Ingold]

<p>Film usually cups so the edges turn to the emulsion side. In a glass holder, usually only one glass has an anti-Newton treatment - the side away from the scanner. (A-N treatment is an etched pattern, which affects sharpness if used on the lens side. The emulsion side is less reflective than the back, and should go toward the lens. If you use a spacer (which can be a thin strip of tape on the glass between frames), it should go between the back of the film and the top (A-N) glass.</p>

<p>I use a thin mask on a flatbed scanner, with the film emulsion side down. The mask provides a little space (<0.5 mm) and blocks extraneous light which can reduce contrast in the scan. A piece of A-N glass on top keeps the film flat during scanning.</p>

<p>Film you process yourself with a Photo-Flo rinse will lay dead flat after air drying. Commercially processed film is dried with heat and usually coiled up before cool. It takes a set that never seems to go away.</p>

[cabbiinc]

<p>Great minds think alike Larry.</p>

[larrydressler]

<p>Well at least one great mind did. I am just a hack. :D</p>