blotchy negatives

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Every film i have developed so far have had brownish cloudy patches mostly in the middle of the pictures (ruining a few good shots too). When developing the negatives am i supposed to agitate them for the whole 10 mins or can i just leave them sitting? and will this be the cause of the patchy negs (as i have done the latter)?Also is there any way of retrieving the fixed ones i've done?Cheers

-- stephanie driver (stephie9000@hotmail.com), August 16, 2001

Answers

Stephanie,

By the way it sounds you have irregular agitation during processing; you can shake your tank like a cocktail shaker right through the process but if the flow of solution is irregular you still end up with blotchy negatives, often even worse. Here is a checklist of do's and don'ts:

Never use a tank to more than its half capacity, and use just enough solution to cover the spiral. For instance, a Jobo UniTank 1500 can ostensibly take two spirals of 35mm film, with 485ml of solution. To ensure eveness, only use one and 250ml of solution, and be sure that the spiral is properly clamped down.

Follow the agitation routine to the letter: over agitation will cause an extra rush of solution through the sprocket holes leading to streamer patterns.

But the brownish patchiness you mentioned was more likely to be irregular fixation, and the same also applies. Make sure of the potency of your fixer before pouring it into the tank.

I hope the above will help to solve your problem.

-- Samuel Tang (samueltang@austarmetro.com.au), August 17, 2001.


You could try re-fixing and re-washing the cloudy negs, with fresh fixer and plenty of agitation.

-- Chris Ellinger (chris@ellingerphoto.com), August 17, 2001.

It sound like insufficient fixing could certainly be the problem.

-- Ed Farmer (photography2k@hotmail.com), August 17, 2001.

Stephanie, it's hard to be sure from the description, but (assuming that you're a novice) it sounds to me like you probably screwed up loading stainless steel reels. It's easy to do. What may have happened next is that a couple sections of the film ended up being pressed against each other. This keeps developer and fixer from getting to that spot. Thus, there will be a patch with undeveloped emulsion (so it doesn't get darker) and the same patch is unfixed. So the original emulsion (just like new film) remains.

If what I am guessing IS true, then refixing (remember to rewash, also) this piece of film will cause the brownish patch to disappear, leaving only clear film in it's place (ie, NO image). If this actually happens, the cure for the future is to be very careful loading film onto the stainless steel reel. I know there have been a number of threads here about techniques of loading reels; you could look some of these up. Good luck!

-- Bill C (bcarriel@cpicorp.com), August 20, 2001.


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