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Jay Decker
9-May-2010, 14:30
Started shooting and processing B&W sheet film in a Jobo 3005 drum. Received some good advise for starting with an 8x10 camera, which was get some Efke 25, because it is relatively inexpensive, and shoot way. I've been happily shooting with Efke 25 and started using some Ilford FP4+ and TPX along the way. And, I've noticed that I have far fewer "flaws" (little spots/imperfections) in the FP4+ and TPX negatives.

Questions:

1) Are these flaws more likely due to my handling and processing of the film, or more likely due to due to manufacturing imperfections in the Efke 25 emulsion?

2) If the flaws are more likely due to my handling and processing, is there something that makes Efke 25 more prone to damage and what can be done to avoid it? Or, is this just one of those [turn on Foghorn Leghorn (http://www.youtube.com/watch?v=KTwnwbG9YLE&feature=related) accent] "Son, welcome to the world large format film photography!" situations.

3) Any recommended articles, books, etc. on handling sheet film and processing to avoid imperfections?

Thanks,

Jay

Gem Singer
9-May-2010, 15:31
Kodak and Ilford harden the gelatin in the emulsion of their films.

The gelatin in the emulsion of Efke films is very soft when wet.

It is more prone to damage.

The "Film Developing Cookbook" by S.Anchell and B.Troop is loaded with valuable information and is well worth reading.

ic-racer
9-May-2010, 16:42
White spot, black spot, opaque spot, clear spot??? What kinds of spots were you seeing.
The most common is going to be the clear spot caused by dust on the film at the time of exposure.

Jay Decker
9-May-2010, 17:41
White spot, black spot, opaque spot, clear spot??? What kinds of spots were you seeing.
The most common is going to be the clear spot caused by dust on the film at the time of exposure.

The image below is should not have the dark spots (except the darker area on the right edge, which is part of the subject hair) and the little pin prick size white spots are not dust on the negative. The scan resolution in about 600 to 800 spi.


http://monkeytumble.com/tmp/Scan-100425-0004.jpg

Jack Dahlgren
9-May-2010, 22:03
When you say the white spots are not dust on the negative, what are they then? Are you looking at the negative and seeing something or do they just show up while scanning?

Jay Decker
9-May-2010, 22:32
When you say the white spots are not dust on the negative, what are they then? Are you looking at the negative and seeing something or do they just show up while scanning?

The pin point sized white spots are black little points in the emulsion of the negative.

Gem Singer
9-May-2010, 22:34
Or dust on the scanner glass?

Jay Decker
10-May-2010, 05:44
Or dust on the scanner glass?

There is some dust on the scanner that shows up as dust, but the dark spots are are not and the little pin point size spot are in the emulsion.

Greg Blank
10-May-2010, 10:55
White spots that appear on the negative as density are either
as a result holders that have scratches...light bouncing back through the
film. Or less Likely embedded in the emulsion at the factory.

Jay Decker
10-May-2010, 11:01
White spots that appear on the negative as density are either
as a result holders that have scratches...light bouncing back through the
film. Or less Likely embedded in the emulsion at the factory.


Sounds like the general consensus is that it is my handling and processing that are the most likely causes of the non-dust spots. Thanks...