Static Discharge on 5x7 sheeet film


Stephen Harrison (SH@stephenharrison.com)
Wed, 21 Apr 1999 22:02:45 -0800


I am having a problem with static electricity starburst patterns on my film
noticeable after the film is developed. My film is 5x7 HP5+ and after the
film was exposed, each sheet was inserted in a clear polypropylene negative
sleeve. I am in Calif and the humidity runs in the 50% range. The negs were
months later removed from the sleeves and tube developed. The film was
loaded and unloaded in the darkroom and not in a film changing tent so I
can rule out the possibility of the film toughing the fabric of the tent.
Of late,I have been getting quite a lot of starburst discharges quite
noticeable on the film. I assume that this is happening upon removing the
film from the sleeves. For some reason, my usual 7x17 inch film rarely has
this problem and I use the same material for film sleeves there also but
there have been occasional cases there too. I have no idea why this last
batch of 40 or so 5x7 inch negatives should have so much discharge? My
shoes are rubber soles and the floor in the area where I download the film
is tile and not carpet.
1) Have others had this problem of static discharge on the surface of the
film?
2) Any convenient methods for better grounding? Perhaps I have been sloppy
in removing the film from the polypropylene sleeve and have dragged it
generating the charge. Does polypropylene rubbing against film generate
electrical charge when abraiding against each other?
3) Do antistatic industrial mats help on the floor? Ahntistatic gloves? Or
special shoes?

Thanks in advance.
Sephen Harrison



This archive was generated by hypermail 2.0b3 on Thu Oct 28 1999 - 21:39:32