Help with Epson 3200 - Strange circles

[michael_joubert]

I scanned a piece of 4x5 positive film last night on my Epson 3200 at

1200 dpi and noticed some strange circles appearing towards the

center of the sheet, shaped like a finger print. (They are not in

fact figer print marks on the film - it has never been handled). I

thought it may been something in the emulsion that the scanner was

picking up so I tried another sheet and the same thing happened but

in a slightly different location. As I raised and lowered the

scanner lid I noticed that the light source was creating these

circular reflections on the surface of the film. I can only assume

at this point that it may have something to do with the film 'sagging

towards the middle and that somehow the light is causing these

circles? Please take a look at the attached images. The red circle

identifies the location and size of the circles and the other crop is

a close up. Anyone else had this problem before? Any suggestions or

help would be appreciated!!

[bw]

They are newton rings. That is where the film is in contact with the glass.

 

"Newton rings

A series of concentric circles that appear on a scanned image when a thin layer of air exists between the glass scanner bed and the image being scanned. Newton rings appear when light waves are reflected from both top and bottom surfaces of the air between the glass and the image, interfering with the resulting scan."

 

Source: http://www.rodsmith.org.uk/photographic%20glossary/rods%20photographic%20glossaryN.htm

[tim_atherton9]

They are called Newton Rings and come from the very smooth/shiny film emulsion touching the glass.

 

This is also an old problem in using darkroom enlargers with glass film holders, or in contact printing.

 

If your film has a les shiny side, try turnign it over.

 

 

Otherwise you could try taping the edges or corners of the film inthe holder to hold it taught so it doesn't sag and touch.

 

After that there are solutions like replacing the canner flatbed glass with anti-newton glass or such

 

search for newton rings on here or on google and you will find tons of information

[jon_shiu]

One guy tried turning his scanner on side, but I don't know if this is practical.

[wilbur_wong]

Definitely Newton rings. I suggest turning the film over (upside down) which perhaps might prevent the sagging of the film and causing the contact with the scanner glass. You can easily flip the image in photoshop or other software.

 

(The contact at a specific point between the film and the glass surface is not consistent, and as this space gradually widens away from the point of contact, light rays bouncing back and forth in the air between these two cause "interference" in the light. The lighter ring is where the light wave length reinforces itself, and the darker ring is where the wave length cancels itself.)

[ellis_vener_photography]

Try these two solutions possibly together.

 

1..) Flip your film

 

2.) take some very thin paper -lighter weight than a standard businesscard -- and cut 1"

squares and place these under the corners of your film holder and possibly in the middle

of the long side of the holder as well.

[brian_ellis16]

I'm not familiar with the 3200 but on the flat beds I've owned placing the film emulsion side down on the glass should fix the Newton ring problem you're having, at least it always has for me. That will require you to flip the image in your scanner or Photoshop since it will then be backwards but that should be simple to do.

[ashtonsmith]

I've never done it with my 3200, but several people have oil mounted film on the 3200.

There is a tutiorial somewhere on the internet. Oil mounting is the best way to avoid

Newton rings. A thin layer of oil goes between the glass and the film removing the air gap

that causes the rings. Just about all drum scans are oil mounted. Downside: You have to

clean the oil off of the film. There are several companies out on the net that make the

supplies for oil mounting.

[dmin-99]

If you use fluid to eliminate the Newton rings you'll probably want to use KAMI mounting fluid. Good luck finding a "small volume" supplier, last one that I found would only sell it by the case (4x 1 liter). If you plan on doing this a lot you may want to change the glass with an anti-reflection coated glass. Also, does the 3200 allow focusing on the glass when the transparency mode is engaged? I know my 1680 does. It will make a difference as far as sharpness goes.

 

Regards,

Wayne

[mbrianmills]

I found that I was getting the Newton Rings on my scans on the 3200 also, and all I did was turn it over (emulsion side up-as recommended by others). Flip it in PhotoShop or your favorite picture editing software and all is well. Now it is routine for me to make sure that after scanning I immediately go into Image-Rotate-Flip Canvas Horizontal.

[perry_cas]

I have a 3200 also. Good advice is given by other members here. Trying to keep a 4x5 flat on the E3200 carrier is v hard. perhaps you might want to start looking at wet mounting. The member who mentioned finding consumables in small amts is dead on in my opinion. I couldnt find any at all in Australia. I gave up and ordered a kit. http://groups.yahoo.com/group/SCANMAX/ have a look at this site it might help.

Perry