Is this emulsion 'damage' due to a light leak or chemicals ?

[NickL]

Hi,

I used my 1910-ish half-plate camera for the first time yesterday. I'm awaiting film for it, so I made up a 4 x5" adaptor so I could test a new shutter blind and see what the image from the Taylor Hobson R.R. lens looked like. I developed the Foma 200 negative using a 2" dia. x 6 1/2" long tube with endcaps. I've developed six negatives from my 4x5" Sanderson this way without any major problems, but on this latest one a corner of the negative has turned grey with a clear halo. I'm not sure whether to go looking for light leaks or if it occured during development.

I leave the neg in the tube until it is fixed, so I don't know what stage of the developing the area appeared. I haven't yet painted the half-plate to 4x5 adaptor, so there is some shiny aluminium/aluminum behind the negative. The dev & fix are Adox Atomal 49 & Adofix P11. I mixed a litre of each 27 days ago. The stop is 2% diluted white vinegar. I have been transferring the film from the DDS into the tube and then pouring the dev into the tube through a funnel. This is done in a walk-in cupboard and then I take the tube to the bathroom where the blackout isn't as good. The bottom of the neg is usually above the level of the dev, but perhaps on this occasion the corner of the neg moved in the tube. I think it was a few minutes before I shook & then started rolling the tube. Would too long without agitation cause this result ? Thanks for any suggestions.

Other than this issue I'm encouraged with the initial results.

Nick

[Jim Noel]

It appears you did not have enough developer, so that strip received little development.
I use vertical tubes when using the EMA process and always make sure there is enough developer to insure no airspace in the tube.

[Alan9940]

Looks like a development issue to me. The negative probably moved above the level of developer solution during the shake routine or during the rolling agitation; I've had both happen with BTZS tubes. During rolling agitation, the film can "twirl" in the tube causing one corner to stick out above the solution when the tube is set upright. When I made my own tubes, I carefully measured the tube length along with the depth of the endcap such that the bottom of the sealing cap is very close to the top of the film. This helps to prevent negative movement. Also, 2" tubes sound awfully small; I use 3" (I.D.)

[NickL]

Thanks for the replies. I have noticed that the film can move inside the tube during development. The longer tube length was really so I could move later to half-plate with the same tube. Also, the tubes were ready machined to a fixed length which I appreciate now is a bit long for 4x5" (though the BTZS tubes seem quite long for 4x5). One learns as one goes ! I think I'll repeat the photo with a different development technique & see if the defect re-occurs.

[Nigel Smith]

That is a weird shape/angle for insufficient developer. You do agitate don't you? Having said that, I haven't got another explanation!

[koraks]

Looks like the sheet stuck to the side of the tank on that corner.

[NickL]

I took another 4x5" (this time with a 5" TTH Primoplane lens) and started the 10 sec shake and then alternate rolling soon after pouring and putting the cap on the tube. No strange effects this time. It will be good practice to keep the time from pouring to agitation to a minimum since although the bottom of the 4x5 should be above the top of the developer when the tube is vertical, when I go on to half-plate the bottom of the neg will be in the fluid when it is poured.

Is anyone else using the Adox powder chemicals ? I'm using a shake and then alternate rolling for the 3 stages: developer for 8 mins, stop for 1.5-2 mins, and fixer for 4 mins. All at 20 deg C. There is a light band of halation layer (I presume) after removing from the tube after fixing, but that comes out in the water wash.

Nick