From: Shannon Stoney (shannonstoney@earthlink.net)
Date: 06/27/02-10:23:52 AM Z
Thanks for all these ideas. I think you are right that it's probably
particulate matter in the water or developer, or dust from the camera. I
will go clean my camera right now!
--shannon
----------
>From: Richard Knoppow <dickburk@ix.netcom.com>
>To: alt-photo-process-l@sask.usask.ca
>Subject: Re: seriously folks...little holes in negatives?
>Date: Thu, Jun 27, 2002, 12:04 AM
>
> At 10:39 PM 06/26/2002 -0700, you wrote:
>>What causes negatives to get little white "holes" or specks in the emulsion?
>>I heard that you can prevent this by using water instead of stop, but I
>>always use water and I get them anyway.
>>
>>--shannon
>>
>>
> Pin holes which are actual disruptions in the emulsion are very unusual.
> Carbonate containing developers can cause some effervescing when the film
> or print is put into the stop bath but this does not commonly result in
> actual disruption of the emulsion. In any case, few commercially packaged
> or widely used film developers use carbonates for accelerators. Most use
> borax or a metaborate, neither of which produces gas in combination with
> acid. Nor does the hydroxide in Rodinal.
> Check the clear spots on the negatives with a strong magnifying glass.
> Look at the surface was well as looking by transmission. Real pin holes
> usually are visible as small deperssions or pits on the surface.
> Its more likely for clear spots to be formed by particulate matter in the
> developer settling on the surface of the film and interfering with its
> development.
> In some areas water has a lot of particulate matter in it and must be
> filtered for photographic use. Its also possible to have particals of
> undissolved material in developers. Filer the developer to get rid of them.
> In fact, its good practice to filter all solutions before use and those
> which are re-used when they are returned to storage.
> Clear spots can also be caused by dust in the camera. This is a plague
> for sheet film but can also occur with 35mm and roll film.
> Loading sheet film without dust getting on it requires some diligence.
> Holders should be vaccumed out and wiped down with a damp cloth. Changing
> bag interiors should get the same treatment. The interior of the camera
> should be vacuumed out and if possible wiped with a damp cloth. You will
> still get occasional dust no matter what you do.
> ----
> Richard Knoppow
> Los Angeles, CA, USA
> dickburk@ix.netcom.com
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