Black and white slides / reversal process diagnose problems?

[Oxleyroad]

I have not run any Ilford film to date as reversal, don't have much of it. I have run Foma negative and reversal, Shanghai GP3, Orwo UN54, Silvermax and Kodak Tri-X reversal as well as Kodak colour Vision2 cine neg film. The Silvermax and colour negative film needs longer developing times than the other films, so I do not dilute the developer and run for the same times as below.

I shoot all my film at box speed, but the colour neg at 1 stop under.


I cannot give a time for multi grade developer, but my times for D19 dilute stock 1:1 at 23degC which I am using right now with Foma R100 both 35mm and 16mm.

Dev 1- 3min 30 const agitation
wash
bleach - 60 sec const agitation
wash
clearing bath - 60sec const agitation
wash and open tank to dark room lighting 2x 75W globes for 2 to 5 mins
Dev 2- 90 to 120 sec. Same developer as Dev 1
Wash
Fixer - 2 mins
wash

I have run many test strips of bracketed film, and I do this for each new developer or when I store mixed developer for more than a fortnight just to confirm my times.

Trust this helps.

[NDP_2010]

thanks

[NDP_2010]

Had a look for recipe for dichromate bleach,

what concentrations are people using (2g/L?) or more concentrated.


Thanks.

[NDP_2010]

Also, is thew sulfuric/dichromate bleach one shot or can it be reused multiple times?

[NDP_2010]

anyone? :P

[Tofek]

You can use 5g/L of potassium dichromate or 10g/L if you want a stronger bleach. It's reusable a few times, but the amount of oxydant Cr2O7(2-) isn't unlimited since it decreases each time you bleach. Add about 10mL of pure H2SO4.

[NDP_2010]

You can use 5g/L of potassium dichromate or 10g/L if you want a stronger bleach. It's reusable a few times, but the amount of oxydant Cr2O7(2-) isn't unlimited since it decreases each time you bleach. Add about 10mL of pure H2SO4.

thanks

[Athiril]

Sorry multiple times. I never bothered being accurate in measuring dichromate bleach, I just inspected until the bleaching was done, if it was too slow for my liking I increased the strength, you need very little sulphuric acid in my experience.

I've done some good Tri-X 1600 and 3200 slides with HC-110 as first dev using Thiocyanate.

[Gerald C Koch]

When the slides are too dense then either the film requires a lesser EI or the time in the first developer needs to be increased. If the slides are too thin then the film requires a greater EI or the time in the first defveloper needs to be shorter. Film for reversal processing is usually not shot at box speed. Remember this is reversal processing and things work sort of backwards. The exact EI varies from film to film. If you are not following a recommended procedure for a specific film then you will have to bracket at first to determine what EI is best.

A 1 min exposure to a 250W photoflood lamp should be sufficient for re-exporure. When using SS reels the film can be left on the reel. Just hold it approximately 2 feet from the light and move the reel so the light can reach all portions of the film. A re-exposure is not needed if you use a fogging developer as given below.

The second developer or a fogging developer goes to completion and so over development is normally not a problem. A simple re-useable bath containing 100 g of sodium carbonate and 2 g of thiourea per liter can be used instead of a conventional developer. This bath can be saved and reused several times. A commercial sulfur based toner can also be used. Both baths yield pleasing sepia colored slides. The film should not be fixed again after either of these baths but should be washed thoroughly. The T-Max films do not give good results with with thiourea or sulfide developers.