Archived posting to the Leica Users Group, 1998/09/06

[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]

Subject: Re: [Leica] Invert or rotate
From: "Robert G. Stevens" <>
Date: Sun, 06 Sep 1998 13:52:09 -0300


It has been about ten years since I used a Patterson tank, but from memory,
I think the instructions were to use the rotating method for the first
thirty seconds and to tap the tank to dislodge air bubbles when you first
put in the developer.  The rest of the inversions were to be done
regularily but not too agressively or you would get surge marks.  Surge
marke are darker areas around the sprocket holes where the developer surges
through when the tanks is agressively inverted and thus develops that area

In practice, I would tap and rotate the reel for the first thrity seconds
of each chemical and then invert followed by a few twists of the reel,
using the ten seconds of aggitation each minute method.

If in doubt, read the directions that came with the tank.


Robert Stevens
At 08:30 AM 9/6/98 -0700, you wrote:
>I use Paterson tanks for developing 35 mm and 120/220 mm film.  Each of
>these tanks come with a device with which you can rotate the reels back
>and forth while the tank stays on the tabletop.  I use this rotating
>method instead of inverting the tank, one back and forth rotation
>substituting for one full (90 degrees and reverse)  inversion.  I find
>this method simpler and less messy since there's no possibility of
>spillage and I don't even have to use the tank cover.
>I would like to solicit other people's opinions about this method.
>There may be advantages/disadvantages to either method that I am not
>aware of.
>Thanks in advance.