Jumping in - I just ordered some Harman Direct Positive Paper

[pbromaghin]

No preflash. I did 2 test sheets but they both were too exposed. Going to try again with lens stopped all the way down and shorter time increments. Will refix this one. This won’t happen until next weekend. Till then, many thanks!

 

[NB23]

Underfixing

 

[pbromaghin]

I just realized I never followed up with the results. Probably because they were so bad.

Once in the fixer, the image (shown on previous page) started getting darker and darker, finally going completely to black. The good news is the pink went away. I haven't given up, but decided to pull back a bit and spend time dealing with my Vivian Maier-like developing backlog. One less mess to leave for Gramma Mary if I die of Covid.

 

[Donald Qualls]

That doesn't sound like what fixer should do -- that sounds like the paper went back into developer.

 

[DWThomas]

That doesn't sound like what fixer should do -- that sounds like the paper went back into developer.

Well it's direct positive paper -- which I've never used -- but maybe if it's un- or badly under- exposed it would go black in fixer?

 

[Donald Qualls]

Well it's direct positive paper -- which I've never used -- but maybe if it's un- or badly under- exposed it would go black in fixer?

Hmmm. I don't see how that would happen without development, however. The emulsion is treated in some manner that makes it develop black unless exposed to light -- but it still ought to fix out white, since nothing is developing the halide.

 

[pbromaghin]

I really don't get how it's even possible for this stuff to work with regular paper chemicals.

 

[Donald Qualls]

I really don't get how it's even possible for this stuff to work with regular paper chemicals.

Ever seen Ansel Adams's image "Black Sun"? That was a case of reversal due to gross overexposure on old film stocks (modern film won't do that, AFAIK). There were direct positive films, back in the day (primarily intended for duplicating), that were pre-exposed to produce a reversed image with a regular dev/stop/fix process. The emulsion on HDP is chemically treated to do the same -- fully fogged as sold, but light exposure reduces the amount of density, to a point where after five stops or so above threshold, it develops as white (i.e. produces no image silver).

 

[pbromaghin]

Interesting. Thank you Donald.

 

[DWThomas]

Hmmm. I don't see how that would happen without development, however. The emulsion is treated in some manner that makes it develop black unless exposed to light -- but it still ought to fix out white, since nothing is developing the halide.

The described sequence perhaps isn't clear, but I read the post as "when it was put in the fixer" which doesn't rule out that it was developed. And it seems logical that a positive photo in a coalmine with the lights out (or a lens cap left on!) should be black. (But I should probably stop typing because I've never used the stuff and think its chemical process is a bit mysterious anyway.)

One could experiment with small snips of the film 1) unexposed, and 2) left out in room light to produce some data points.

 

[Donald Qualls]

Direct Positive ought to come out black if developed without exposure, and white if fully fogged before development -- and white if fixed without development, I'd think. Fixing a scrap without development would make me confident I understand it...

 

[pbromaghin]

Post 78 2nd sentence should start with "Once put back in the fixer,". Just to be clear, this was done the next day after it was judged to be insufficiently fixed.

 

[pbromaghin]

I just now stumbled onto the cause of the disappearing image - the aperture was set to f/64. This appeared while readying the camera for a foray to a local park for some really cool bare trees. Thanks again for all your help. Hopefully my next postings will show some success!

It's bright, beautiful, Sunny 16 in Colorado, the calm before Snowmageddan shows up this weekend. A cloudless bluebird day, so I will be taking RalphLambrecht's suggestion and use a yellow filter to darken the sky a bit.

 

[pbromaghin]

This error bothers me. The conclusion does make complete sense, given that the image disappeared and I found the aperture set to f/64 when I picked the camera back up. However, I don't know what unlikely series of events would have led to that kind of error, considering I opened it up wide open to focus the camera before each shot. It's not that I 'm not that stupid, but that one would really have to out of one's way to make that particular error.

 

[Donald Qualls]

More than that, I don't know that this would happen with a grossly underexposed image on Harman Direct Positive. Where I've seen it on YouTube, it seems to develop out more or less normally, only as a positive -- so if you were, say, five stops underexposed (f/64 instead of f/11), the paper should just develop out to black, without any "disappearing" image. It ought to be easy to test, at the cost of a couple sheets of the material -- shoot one at correct exposure, around EI 3 to 6, and one at the same shutter speed but f/64. It would be most instructive if you could manage to shoot video of the underexposed sheet developing (even low quality cell phone video under red safelight would show us more than "the image disappeared".

 

[pbromaghin]

Good advice, Donald. Thank you.

 

[radiant]

I have to admit that I exposed few papers, opened a new box, mixed new developer because I thought my papers or developer had gone wrong. I just didn't notice that I was shooting at dusk and the lightning conditions had changed enough stops to make the paper completely black after development