Re: Sprocket shadows & little white spots

[Ian D Wilson <idw@xxxxxxxxxxxxxxx>]

aeophoto@xxxxxxxxxxx wrote:
> My latest roll of film had a little, white spot problem that printed
> dark spots on the print.  It cannot be little acid holes from too
> strong stop bath because I no longer use stop bath for development -
> just a water stop.  I have had the problem before when it was a foggy
> day or rainy/snowy day and it was explained to me that the infrared
> was picking up the little bits of water in the atmosphere.
> 
> But, my favorite image in my most recent rolls has the spots in the
> sky and on the grass.  It was not raining nor misty.  It has been
> raining off and on here, but did not rain nor mist that day.  The
> ground was wet; the grass was wet.
> 
> Could this also be an agitation problem?  Or something else?  If not,
> has anyone else had the problem and figured out a way to diminish it?
> Can you stand at a different angle to the light?

Sounds like a development problem to me.  Dust tends to give dark spots
on the negative which print light; what you describe sounds like very
small areas of undeveloped film.  Are you using a liquid or powder
developer?  If the latter, is it possible that there are specks of
undissolved powder in the developer?  In either case, is it possible
that there are air bubbles being introduced as the film is developed? 
I'm a "stirrer" rather than an "inverter" when it comes to agitation;
also, I've found that 10 seconds every minute is plenty of agitation.

Also, your spots aren't in a regular pattern, are they - I know some
cameras have dimples in the pressure plate which can cause problems with
IR film.

> When I have had the problem with rainy/misty days, there are only a
> few spots here and there and they have never ruined an image on their
> own.  This recent negative, which I LOVE otherwise, is unprintable.

You could always try good old Farmer's Reducer to bleach your black
spots, and then spot them back to the correct shade of grey.

> Thanks.  (I wanted to see if this was mentioned in Laurie White's
> infrared book, but I've had the book on order for about 6 months and
> have never received it.  Something to do with reprinting?)

Laurie White's book is certainly available in the UK - I bought one from
Blackwell's by mail order less than a month ago.


Hope this helps,

- -- Ian.

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Dr Ian D. Wilson         |  Email:  iwilson@xxxxxxxxxxxxxxx
Principal Engineer       |  WWW:    http://www.telemedia.co.uk
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