B-Dag … no image

[yowyip]

Hi There,

I tried my hand at making a Becquerel in the summer, and was successful. This time around though things arent going so well.

I’m doing a studio still-life shot with 3 X 1000 watt studio lights. One with a blue gel. One bounced. But no image. I’m on my 4th attempt.

Exposure times have ranged from 3 minutes – 15 minutes… nothing. Not even a vague image.

Developing time has varied, from 2 hours – 8 hours under a hot 1000 watt light (with a fan on it). No latent image appears (as it did under the sun in the summer) within the first few minutes.

So I am wondering, if it is perhaps my polishing or plates that is to blame.

Sensitization appears to be working (a dark first cycle magenta). But perhaps I have not polished my plates enough to “chemically activate” the silver ?

Also these are new, electro-plated brass plates. The last plates I used before were clad copper plates. Could this be the culprit of poorly made electro-plates ? Has anyone else used plates made by Zappfe silver in seattle? They look fine to me, however.

Any other possibilities for no image at all ?

[Pobboravsky]

What f/stop was used on the lens?

Subject to lens distance?

EV (exposure value) measurement using a light meter?

Irv

[yowyip]

What f/stop was used on the lens?

f.8.0

Subject to lens distance?

not sure, distance from lens to subject is about 1.5 meters

EV (exposure value) measurement using a light meter?

10.6

Irv

not sure how to calculate this…

[yowyip]

Also the studio lights I’m using are tungsten photo-flows. Should I try using daylight strobes instead? (those are the only other lights I have available right now).

[yowyip]

Also the studio lights I’m using are tungsten photo-flows. Should I try using daylight strobes instead? (those are the only other lights I have available right now).

[Pobboravsky]

Thanks for the info.

A. f/8 does not let much light through. I would open the lens to its widest aperture. [f/5.6 doubles the amount of light getting to the plate; f/4.5 triples it.] Use the fastest lens available.

B. Move the lights closer to the subject, if possible.

C. A very rough exposure estimate for EV=10.6, @ f/5.6 is 30 minutes. Moving the lights closer would increase the EV (light intensity) and shorten the exposure time.

D. If the subject has a bright white it will appear first during Becq-dev’ment. I forgot to ask the color of the filter used for Becq-D??

Good luck,

Irv

[yowyip]

Thanks for the quick response !

I just tried a 35 minute exposure, and only got the tiniest of the white area, still totally underexposed, but at least I have something. Will try a full hour (good thing its a still life), and cross my fingers.

Iam using rubylith for the developing. Whats a good guestimate of how long for the developing? Is 8 hours too long ?

thanks again!

[Pobboravsky]

You are making progress. I don’t know what changes you have made aside from increasing the exposure to 35 min. Please include f/# of lens and EV (exposure value). Also dev’g time. Please describe polishing steps.

Iodizing to a yellow with a reddish tinge may provide a bit more sensitivity.

Increasing the Becq-dev’g time will help.

Guessing that 35 min exp should have given a stronger image but not knowing what changes you made makes my guessing harder.

Good luck,

Irv

[Author]

Posts