5"x4" under developing errors

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When developing my 5x4 sheet negatives in a developing tank i get lines of underdevelopment down both sides of my negatives. I realise this is possibly due to the grooves that hold the negs in place during devlopment but I am yet to find a satisfactory way of erradicating them through agitation or otherwise. Any help or suggestions would be greatly appreciated. Thanks, Nick

-- Nick Morrin (nickmorrin@hotmail.com), March 13, 2002


Describe your agitation pattern, Nick. I suspect that's the problem.

-- Alec (alecj@bellsouth.net), March 13, 2002.

I don't know what tanks your using, but if they are Combi tanks, then here are a few things to consider. Do not use the funnels or the spouts. Work in total darkness and remove the lid to change the chemestry. Just pour it in and out. Those top valves are just too small to allow the chemestry to pour in fast enough.

When agitating, invert the tank so that the axis is on the wide part of the tank, so that the narrow side turns end over end. Invert 2 or three times is all you need per cycle. Don't shake it. This will keep the weight of the solution from pressing on the film so the film does not jump the channels.

I personally have a tank for each step from pre soak to washing with the chemestry in each tank, ready and waiting so all I to do is dip the holder in. I use a lid so can turn on the lights.

Hope this helps.

-- Rob Pietri (narrationsnlight@aol.com), March 13, 2002.

I had marks such as you describe when I processed 4x5 film using an Unicolor tank. You slip the film into groves that hold the film to the curve of the inside of the tank. The one ruined sheet was loaded such that the emulsion touched the side of the tank. Where that occured chemicals couldn't reach the film and I had a couple of nice clear marks where development didn't take place. I realized that the film should be loaded so that the emulsion side is loaded "inward" towards the centre of the tank. Then since the film's emulsion can't touch the side of the tank the chemical solutions can get to all parts of the sheet.

-- David Grandy (dgrandy@grandyphoto.com), March 13, 2002.

To: Nick & David

You're right about the Unicolor drum. Emulsion IN only. I've been using a Unicolor Drum and motor base for years and never a poorly developed neg yet. Constant reversing agitation (for me) increased contrast a bit. But I'm printing on a cold light head, so it compliments the contrast increase.

BTW I also have no worries about developing 4 negs at a time. They usually overlap in the drum at some point in developement. But never has there be a problem. Amazing.

Now only if my images were better . . . .

S. F.

-- Steve Feldman (steve@toprinting.com), March 13, 2002.

Thanks for your response Alec. I use a squared tank that has grooves down either side that are curved so that they hold the negs lengthways in a curved position. I always ensure that the emulsion side of the negs are on the inside of the curve. After pouring in the developer through the hole in the top and keeping the tank upright throughout I move it forwards, backwards and then left to right, this being one cycle of agitation (as recomemded by my uni lecturers), although I am currently experimenting using different techniques to get rid of this under development problem. Hope you can help, Nick.

-- Nick Morrin (nickmorrin@hotmail.com), March 16, 2002.

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