Latent image keeping properties of homemade dry plates

[ProfessorC1983]

I'm considering taking a long cross-country road trip, packing an 8x10 and taking a series of images on homemade dry plates along the way. However, I won't be able to guarantee darkroom access and I'd rather not have to lug chemicals and trays and whatnot around the continent.

Wondering if anyone here can comment on the latent image keeping properties of basic emulsion recipes? I make a straightforward ammoniacal Br/I recipe, no chemical sensitizers but with added erythrosine, bromide, benzotriazole, and ethanol. Would it be reasonable to expect such an emulsion to keep latent images for several days to a few weeks without degrading? (Yes, I'll test of course, but don't know exactly when I'll be leaving on this trip nor how long it may last.)

Also, I've read through PE's book and old posts here, and see that he recommends iridium chloride as a dopant to improve LIK. Has anyone had success with that method or are there other ways to stabilize latent images for longer?

 

[dwross]

No need for expensive dopants. Keep it simple (and cool). Edward Curtis and others used the then-new photographic technology of silver gelatin dry plates to travel the American West without the portable darkroom required for wet plates. If you don't let your unexposed and exposed plates get over-warm, they will last for weeks. But, of course, test all you can before you go. Sounds like fun! Have a great trip.

 

[RogerHyam]

When I go on a trip the main issue I have is exposure anxiety!

Normally I develop plates within a day or two so I'm continually getting feedback on whether my reckoning of the exposure (based on an incident light meter and some dead reckoning from weather and time of day and year) is correct or not. If I go to a new location many of those factors change (that's why we go after all) so my reckoning can drift off. I can delude myself by quite a few stops

I'm just back from a week away and have plates to develop. I wish that I had developed one or two during the course of the week to check everything was working. I think if I did a longer trip I would definitely take kit to develop the occasional plate but keep most of them to process when I got home. I would consider making some smaller plates just for this purpose if it was a major expedition.

I wouldn't worry about latent images unless I was leaving them months or years or as @dwross says they were getting hot - or damp.

The one place I've had emulsion go off is before I coat, in the fridge. I had some left over in the back of the fridge for a couple of months and when I coated the plates had bits on them. It was mould! I might reintroduce thymol into my recipe to stop this or just make sure I coat in a reasonable time. I've exposed a couple of those plates on this trip. It will be interesting to see the effect. Perhaps a new "creative filter"?