4x5 B&W proccessing

[shapirophoto]

I just finished processing 4x5 negatives for the first time ever. Some issues I ran into were when I dried (in a drying cabinet) I had some streaks and a couple scratches... Now I used a film squeegee, is that not recommended? I also used photo-flo and I developed using a Jobo reel drum and then when I used photo flo I dunked the reel with film on it into the photo flo solution a couple times, is that incorrect? Any tips? Are there any great resources out there for me? I really LOVE large format and have every intention to continue with it but I want to get clean negs. :D

[ic-racer]

I just finished processing 4x5 negatives for the first time ever. Some issues I ran into were when I dried (in a drying cabinet) I had some streaks and a couple scratches... Now I used a film squeegee, is that not recommended? I also used photo-flo and I developed using a Jobo reel drum and then when I used photo flo I dunked the reel with film on it into the photo flo solution a couple times, is that incorrect? Any tips? Are there any great resources out there for me? I really LOVE large format and have every intention to continue with it but I want to get clean negs. :D

I think the main advantage of the photoflo is it eliminates any need for the squeegee. You can try distilled water to mix the photoflo if you think the streaks came from the photoflo. Jobo recommended against immersing the reels in the photoflo as it may cause a buildup on the reels.

If these were you only problems you did pretty good!

[shapirophoto]

So if I don't use the reels, is there an easier method? And if that's the case no squeegee = no scratches correct?

[Ash]

Increase your rinse time, and then at the end of it take the sheets one by one and dip into photoflo, then immediately clip up to dry (with drips trailing between the tank of liquid and the drying cabinet).

[ic-racer]

I dip in the photoflo like this:

[Charlie Strack]

Good suggestions--here are mine:

Don't use a squeegee--it can cause scratches. It's impossible to squeegee a sheet of film evenly and gently.

Use distilled water to mix the photo-flo.

Don't use as much photo-flo as the instructions say.

Take the film out of the reels, handle by the edges, and slip into a tray. Agitate for 30 seconds to a minute (gently). You can very gently rub the surface of the film with a finger if you see some debris on the film. By this time, your fingers probably have no oil on them from all the processing & rinsing.

Lift out by the edges, clip on one of the corners and hang to dry. After about 30 minutes, you might gently touch the bottom corner with a Q-tip to wick off the accummulated water at the corner, but generally ignore it for 12 hours. Looking will make you decide to do something, and whatever you do probably won't help.

[Nathan Potter]

I've become more fanatical about the final cleanliness of processing negatives - to wit:

Final water rinse is with filtered water. 5 micron filter at least; I use 0.22 micron. It is done in a clean 4X5 stainless steel tank, on the hanger that will be used to dry the film.

Photoflo dip for 30 sec. in tank using hanger as above. Photoflo mixed using 0.22 micron filtered water. Recommended concentration of Kodak Photoflo.

Hang to dry in laminar flow hood or ultra filtered drying column.

The operations above are all done in a the laminar flow wet hood to avoid picking up any dust particles.

The resulting negatives are absolutely clean. I'd be a bit cautious about supermarket distilled water. It's probably better than tap water but some can contain particulates.

Also don't handle the film with the fingers anytime after the final rinse above.

Nate Potter, Austin TX.

[Daniel_Buck]

I use a jobo drum & reel as well. For my last step, I use 6 drops of LFN wetting agent (I'm assuming this is like photoflo?) mixed with a full drum of water. I then constantly invert the tank for 30 seconds, then let it set still for another 30 seconds before opening it. I just pull out the reel, let it drip off for a few seconds, then pull out each sheet with my clips and hang them up with one corner facing down, no squeegee, and no rinseing after I've used the LFN wetting agent. I let them dry overnight just hanging up on the lip of my stove exhaust vent (vent and stove turned off).

I have never had any streaks or drying oddities. I'm using Tri-x 320 by the way, with water straight out of the tap.