Scan-Tech Anti Newton Ring Glass

Does anyone have experience with Scan-Tech Anti-Newton glass? I'm using an Epson V-600 scanner primarily for 35mm B&W negatives. Very happy with the scans , but have been experiencing Newton Rings primarily with Tri-X which curls much more than llford HP5 Plus. Flattening under heavy books helps some as does inserting the negatives reversed, i.e., with emulsion side (concave) down, but this degrades definition. Scan-Tech promotes a thin glass insert which supposedly addresses the Newtons Ring issue; however, the illustration on their website shows a negative convex side up with glass on the top of the negative, the opposite of my situation with 35mm B&W. I have a call and an e-mail in to them, but while awaiting a response, I thought I'd try the RFF community; no response from any RFF member (after one full day), so I thought I'd try Photo.net members. BTW, no response from phone calls to Scan-Tech and an e-mail as well. Thanks for any help or advice you can provide.

Flattening under heavy books helps some as does inserting the negatives reversed, i.e., with emulsion side (concave) down, but this degrades definition.

 

I think the emulsion side should be down as standard procedure. Usually negative strips have the emulsion on the concave side and if the strip is placed correctly in the holder, the holder itself will ensure the film is slightly above the scanner's platen and therefore avoid Newton Rings. It's ideal to have very flat film strips but not absolutely necessary as long as the curve is upwards. Anti-Newton Ring glass works but only if the film is not sandwiched between the anti-Newton Ring glass (being on top) and plain glass, as in the case of scanning on the platen, but not using the holder.

How do you store your film. If you keep it in archival pages, in strips of 6 (or less), in a binder, It flattens out quickly. It's important to do that as soon as possible after processing, before the emulsion completely dries and takes a set.

 

AN glass works by etching the surface so it makes minimal contact with the film. It should be used between the light source and the film, not between the film and the lens.

 

The emulsion side is where the image resides. If it is less clear that way, you may have a focus problem. The emulsion is textured and matte, which is likely to cause Newton's Rings when placed against a polished glass surface. If the film is cupped, it only touches the bottom glass at the edges of the film.

 

Don't place the AN glass directly on the film. Make a mask from black photo cardboard, which is as thin as 1.5 mm. Most flatbed scanners are focused about 2 mm above the glass surface. You can test that by scanning an inclined engineering rule (e.g., Starrett, which has engraved rulings). This, plus a little trigonometry, will demonstrate the true focus plane and DOF.

 

A Nikon glass holder for film scanning has an anti-reflective coating on the bottom glass and AN glass on the top wit 1 mm spacing. It's recommended to place the film emulsion side down.

I think the emulsion side should be down as standard procedure.

I agree, and I would never print a negative conventionally with the emulsion side away from the lens.

However, if I recall correctly Epson instructs the user to do it the other way around. It may have something to do with the scratch removing ICE functionality?

I agree, and I would never print a negative conventionally with the emulsion side away from the lens.

However, if I recall correctly Epson instructs the user to do it the other way around. It may have something to do with the scratch removing ICE functionality?

 

It has to do with ending up with a mirror image of the scan. Put it in wrong and you end up with your right handed little leaguer becoming a southpaw. with the writing on signs, T-shirts, etc., being backward.

Thanks for the replies. Yes, I do file my negatives in Print File Archival sleeves, and yes, they do flatten out when stored this way. Epson advises to insert 35mm strips with emulsion side up, shiny side down. Any curl remaining in the negatives will be such that the emulsion side will be concave; shiny side will be convex and facing the glass What I've read on the internet and verified through observation is that placing the negatives with emulsion side down will result in loss of definition. No reply from Scan Tech. Perhaps they're on a holiday break or have folded. No indication of a holiday break on their answering machine.

The Epson utility can mirror images with the click of a button, which becomes the default until you change it back.

 

Placing the back or the film against a polished surface guarantees Newton's Rings. The loss of sharpnes is due to the focal plane, which is on the glass surface in all of the consumer grade scanners I've owned and tested. Anti-reflective coatings won't eliminate NR, and textured AN glass will degrade resolution. Besides, flatbed scanners have much less resolution than the pixel count would suggest.

 

Twenty years ago, I bought an Epson scanner which had variable focus. It had a single lens, not an array of micron lenses, and cost at that time 3x as much as the so-called photo scanners of today. It's a monster with an SCSI interface.

 

In order to get high resolution "scans" since the passing of dedicated film scanners, many of us have turned to a high resolution (24 MP or more) digital camera, copy stand or fixture, and a macro lens which focuses to 1:1 for 35 mm slides and negatives.