From: Bill Collins (photo@intrex.net)
Date: 06/27/02-08:43:33 AM Z
It seems like particulate matter in the developer would be moved around by agitation and have little effect, unless it stuck to the film.
Bill
---------- Original Message ----------------------------------
From: Shannon Stoney <shannonstoney@earthlink.net>
Reply-to: alt-photo-process-l@sask.usask.ca
Date: Thu, 27 Jun 2002 09:23:52 -0700
>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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