Flatbed scanners and Newton Rings

You can use some hair spray with fine mist on the transparency the side that touches the glass of the scanner and if the enlargement is more than 250 % you can use some gel/oil (long time ago used to be called as scan gel i dont know if it is still available) again on the side that touches the glass. Put a couple of drops of oil or gel on the transparency and tape the edges of the transparency leaving some gap and squeeze out the bubbles if there is any between the transparency and the glass with this way you can enlarge as much as the grain of your transparency allows,

Good Luck,

Rizwan Haider

It seems you need to have a space between the two planes of glass and
the slide. Some scanners (e.g. Afga) come with slide holders for
un-mounted slides to provide the spacings. I guess you can try to make
your own holder with cardboard.

Try using anti-Newton's rings powder which you can get from a prepress
shop. Alternatively, Baby Powder can be used. You need to coat the
surface with a small amount of powder. Clean off the film with a
blower, then a brush, then a film cleaner. You may have some success
with Paraffin film oil. All of these methods are tricky and take
practice. See 4-9 of "Essentials of Digital Photography" by Kasai &
Sparkman.

Peter

hello kevin .. the rings are formed when the film contacts the glass
.. i use a frame to raise the film just off the surface .. no rings at
all .. harry

There are more extreme solutions, too, like using a special oil meant for
floating film on drum scanners, but merely separating with air should
solve the problem.

I really liked the Agfa Arcus II for scanning film and flatbed; I've
always been dubious about dedicated film scanners, because of their lack
of flexibility and their usually persnickety software and hardware.


Glenn Fleishman, unsolicited pundit: read my work #
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I regularily scan Medium format negatives (6 x 4.5cm) on my HP ScanJet 4C
Scanner with Tranny Hood. You can see a sample as picture 1 on page:

#

I dont know what scanner you use or interface, however the main trick is to
scan with no exposrue correction in the scanner software, dont even invert
it. If your interface allows then sharpen at highest point and bring into
photoshop. Invert it in here and under variations add about 4 reds and three
yellows then darken the picture to your taste. You can then try auto levels
(Undo if not desirable) and the grey color picker under Image/Adjust/Levels,
and pick up a middle grey. This should eliminate color casts. Play with the
color balance, brightness contrast and try to slide the Hue slider a bit to
each side to see the results. It is touch and go and no two negs are alike,
but all are invertible.

I scan @600 DPI, and have made very good qulaity prints upto 6' x 8'. Bigger
sizes like 6 x 6 or 6 x9 will result better.

Cheers
NSAY



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Converting color negatives to positives (for those without HP
PhotoSmart Scanner)
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Peter