Lane Dry Plates: What is a practical ISO rating?

[m00dawg]

No that’s for the ASA 2 plates.

Blue 47 filter blocks (approximately) the wavelengths the emulsion doesn’t see, but also chops down the throughput in the wavelengths the emulsion does see, so you adjust your meter two stops up to compensate (remember, ISO setting on the meter is just an electronic gain adjust for the read circuit).

When metering thru a blue 47 filter with J Lane Speed Plates, you’d set ISO rating to 100 and use the reported exposure.

Another way to think of it is...If you don’t compensate +2 stops, then metering through a blue 47 filter will result in +2 stop overexposure.

I think I got that. I had to sit and re-read that a few times Alas I don't have a real Blue 47. Just a set of colored generic filters I was going to use for some trichrome stuff . I bought those in part because finding blue filters has been rather difficult/expensive though I do now see there are some available from various places. So yep I might have to pick up a proper one - seems like that would make metering just a little easier.

[Drew Bedo]

Jane Speed Plats?

[Kiwi7475]

My experience with shooting in a studio environment with incandescent light and modifiers is that both ISO 25 and ISO 2 plates need 2.5 stops more light (is. the “true” iso is lower by 2.5 stops) than what the metering tells me it should, plus then reciprocity/bellows corrections on top of that of course.

Note I develop in Diafine 3+3 minutes, 1 min stop wash with water, Ilford Rapid fixer for 4mim, wash for 10 min, photoflo for 30sec.

[Nodda Duma]

My experience with shooting in a studio environment with incandescent light and modifiers is that both ISO 25 and ISO 2 plates need 2.5 stops more light (is. the “true” iso is lower by 2.5 stops) than what the metering tells me it should, plus then reciprocity/bellows corrections on top of that of course.

Note I develop in Diafine 3+3 minutes, 1 min stop wash with water, Ilford Rapid fixer for 4mim, wash for 10 min, photoflo for 30sec.

Sounds about right. The drop in speed indoors didn’t start getting addressed until the mid 20th C and even modern films lose a stop indoors. Of course the dry plates don’t take advantage of those “modern” innovations.

Diafine! I have a can ready to mix to see how the plates respond to that unique developer.

[paulbarden]

I found that outdoors under heavy overcast conditions, especially during the winter months, the speed of the 2ASA plates is more like 0.5ASA. I've found this to be true when shooting in dense shade conditions as well.

[Doug Howk]

Testing the 25 ASA plates [5X7] in studio with still life. Using Ilford FP4 as comparison [15 secs at f45], the J lane plate exposed for 120 secs; and yielded a thinner but printable image. Lighting was two soft boxes with spiral florescent tubes.

[Kiwi7475]

Sounds about right. The drop in speed indoors didn’t start getting addressed until the mid 20th C and even modern films lose a stop indoors. Of course the dry plates don’t take advantage of those “modern” innovations.

Diafine! I have a can ready to mix to see how the plates respond to that unique developer.

I haven’t done a lot of comparisons against other developers, but I find Diafine works very well with your plates.

[Kiwi7475]

Testing the 25 ASA plates [5X7] in studio with still life. Using Ilford FP4 as comparison [15 secs at f45], the J lane plate exposed for 120 secs; and yielded a thinner but printable image. Lighting was two soft boxes with spiral florescent tubes.

A couple of notes... reciprocity isn’t the same in general so the numbers may not be directly comparable. It would be best to run some test comparisons in the <1 for FP4+ so that reciprocity is not a factor. I did comparisons running each 1/4 of a plate with increasing (doubling) exposure by pulling the slide in 1/4 increments. That saves plates :-)

Second thought is that the emulsion is most sensitive to UV. Every type of light will have a different % of effective power at the range of wavelengths that the plate is sensitive to. Different people may experience different speed depending on the light type. Just like with collodion.

[Drew Bedo]

So do or do not use a UV filter outdoors?

Would using a UV filter give a gain in sharpness along with a drop in effective ISO rating?

How do the J. Lane plates respond to strobes? I use older Vivitar 283s on still lifes indoors.

Is anyone creating Ambrotypes using J. Lane plates?

[ernie57]

I’m only into my first box of plates, so I expect to be fighting the learning curve. I shot some plates last week, outside, middle of the day near the ocean. Held a blue #47 filter over the meter with ISO (I still like ASA better) 100. These plates came out properly exposed. The 2nd outing, I was shooting cars, in the sun, middle of the day, and used the same metering technique, but everything came out very thin. Thin to the point of unusable. The thin ones are drying right now, or I would put up a scan. What is the difference in why I got such thin plates the 2nd outing? Thanks.