Increase amount of thiocyanate / thiosulfate or first developer time (black & white reversal)?

[pkr1979]

Hi all,

I just developed Ferrania Orto at 50 (box speed) and 25 ISO (with 2g thiocyanate/L). Looking over the photos I'd say my son's face looks good at 50 while his hair (blond) looks more correct at 25. Other shots does lack shadow detail - but this is also the case for this film if developed as a negative and compared to a film like Ilford Ortho Plus. Anyway, I'm not sure how to determine if I should increase the amount of hypo (I've just started using thiocyanate) or first developer time? I guess I'm assuming if I increase hypo levels and expose at 50 I'll get the same skin tones while getting a brighter more realistic hair tone?

Cheers
Peter

 

[Nicholas Lindan]

Could you please post scans of the resulting images. We can do little with a description of hair and skin.

 

[pkr1979]

Mobile scans:

 

[pkr1979]

Also... first developer is PQ Universal 1+5 for 12 minutes at 20C, dichromate bleach and Iron Out (which is both reexposure and second developer) for 6 min agitating initially and halfway.

 

[revdoc]

Have you used ortho film before? if not, skin tones might not look the way you expect.

Also, just looking at those scans, 50 ISO looks underexposed, and 25 looks about right. Processing won't change that situation significantly.

 

[mshchem]

These look pretty good. Expect contrast and bracket your exposures.

 

[pkr1979]

Thanks guys. Ive used quite a bit of Ortho-film - in many cases I prefer it. The ones exposed at 25 are slightly flatter and I have to admit it annoys me a little bit. I hade these results with Tmax 400 a few years back (also PQ, no hypo, and permanganate instead of dichromate):

These are exposed at 100 and 200. The one with the bike can also be seen here: https://peterrisholm.com/#jp-carousel-1312

I also like these, but the Orto ones are a lot less grainy and holds more detail (so better suited for 135 especially). I do like the warmth and glow of these though. When I tried reproduce these results it failed. So i either I messed up when I reproduced them or I made an error when I made them the first time and dont know what it is.

Anyway, about the ortho ones, I guess what Im aming for is the brightness of the 25 ones but the 'volume' of the 50 ones.

 

[koraks]

These look pretty good.

Yeah, definitely. It's always a little challenging to judge transparencies this way, I find, because the intensity of the backlight does so much, as well as exposure of the digital image that we're looking at. For instance:

I assume these are the exact same frame. The one on the right looks bang-on perfect, very pleasing (and a compelling portrait to boot). The one on the left looks flat and dark, overall.
I also suspect that the one on the left is more representative for how the actual slide looks in real life.

Overall, I'd be inclined to experiment both by increasing exposure (so going down to ISO 12) and adding more solvent to the developer. It would be great to do some snippet tests of various combinations to find the sweet spot. I think in the end you always walk away with the observation that exposure + chemistry are ideally tailored to the contrast range of the actual scene, which of course is a little inconvenient when working with roll film. Testing with some mixed-scene images would be the way to go to settle on a usable compromise.

So in short, I can only say "continue as you've been doing"; you're going places.

Maybe @Ivo Stunga could chime in as well; he has done a lot of reversal processing and I'm sure he has some thoughts or even pointers to share.

 

[pkr1979]

Id say the original looks somewhere inbetween. But better than both 'scans'

I agree about the backlight. It has a lot to say. That is a regular light table, but the slides looks a lot better using my basement ceiling lamp

 

[Ivo Stunga]

It helps to mask the background/light table as much as possible: with magazines if nothing else. And it helps to have camera on tripod, exposing to achieve exposure as you see it projected > observed. Because very much depends on the quality of light source. You might like in one application and hate in another.
My projection priority dictates the contrast pretty much. Your contrast may vary.

Scanner has harder time picking up info in deep shadows/blacks, but SiverFast double exposure helps there a little - produces quite a flexible tif that has plenty of room for edits to approach the projected image.


My approach usually is to burn a few test rolls in similar lighting to nail what I want nailed and start with plain PQ, cutting rolls in 2-3 strips to have more of that good reversal time. Check if increased time and increased/decreased agitation frequency improves things.
If not, try adding a minute amount of hypo - like 0.4 grams @500ml PQ 1+5 and see if that helps. If too much - reduce first dev time by 2 minutes. If still blown, reduce hypo by 1/2 and try again.

When happy, go for the important roll and tap yourself on the shoulder, you deserve it!

My usual guestimated starting hypo amount for traditional emulsions at their box speed is 0.3g, 12 minutes and 3 inversions every 90 seconds. And again - for projection. You might need some more chrystals or dev time for lighter image.
Aviphot takes way less, Delta 100 way more. It's Time Vs Hypo gameplay. Then comes Agitation.
And temperature, but I never play with that, I keep it constant.