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- Nov 16, 2004
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It's a one shot developer.
They are not recommended for re-use.
Even for one shot Rodinal 1:50 users have reported variations in negatives from re-use.
It's a one shot developer.Do you throw away the mixed developer after 1 film or can you save it a while and develop a 2nd film later? Do you have to extend the total development time for the 2nd film? How many films in theory could be processed before development times are not practical or the working solution is exhausted?
@aconbere I have also forgotten to dilute with the borax solution...and it's because of the stubbornness of Ascorbic Acid going into solution, that I too picked up a magnetic stirrer. Heating up to at least 50C helps a lot, too. My PG has no odour. Did you use the 1+50 dilution with HP5?
I got my PG off of Amazon...
From the original recipe in https://imager.ie/a-simple-phenidone-ascorbic-acid-concentrate-developer/If one were to mix up PC-512 from dry chems alone, sans glycol, for immediate use, what would be the proportions of ingredients?
From the original recipe in https://imager.ie/a-simple-phenidone-ascorbic-acid-concentrate-developer/
For 1 litre of working strength developer. You need the equivalent of 1/50 litre = 20cm3 of concentrate A, i.e.
(20/100) x 12g ascorbic acid = 2.4g ascorbic acid
(20/100) x 0.5g phenidone = 0.1g phenidone
and solution B (1 litre) contains 21.7 (22?) g of borax.
The phenidone is IMO awkward to measure in such small quantity; better measured from a known solution (5%??) in... propylene glycol.
What you propose saves some propylene glycol and the trouble of dissolving the ascorbic acid in hot propylene glycol. As far as I'm concerned I would not go the trouble of weighing the powders for each development.
Plus, who knows? maybe the glycol plays a role in the success of the recipe? Obviously not? not until demonstrated.
Weighing errors start to bite doing this. A scale reading to 0.01g gives 10% error on 0.1g. And if it is a digital scale that last digit is rounded, so it is at best +-0.005g. At 0.5g you are at a more reasonable 2% error.
The propylene glycol mix will last for at least a year (verified personally). It is a bit of an effort to mix up, but I'd rather do it once for a batch.
better measured from a known solution (5%??) in... propylene glycol.
I compared PC-512 Borax with FX-1, blue sky, orange filter.
PC-512 Borax
FX-1
PC-512 clearly gives less grain . An assessment of sharpness seems to depend on whether the relatively smooth edges with PC-512 appear sharper than the ragged but clearly defined edges with FX-1.
The resolution of my scanner ,~80 lppm, is a limitation in the attachments, which are from about 1mm squares of negative.
I developed Delta 100 shot with a Fuji zoom date f2.8 in half strength (1+49+50) PC-512 Borax using the time for full strength multiplied by 1.8.
FP4, HP5+, Delta 400 and Delta 100 have all been shot in the half strength version using the time multiplier of (full strength time) x 1.8
The factor of 1.8 seems about right from the limited number of tests.
What I'm seeing there is that FX-1 is delivering worse sharpness in favor of harsher grain. Of course, limited by crop resolution as Alan said.Just tuned in on this.
I don't find this specific result shocking. In my experience - granted it is fairly limited - FX-1 is a fairly high acutance developer best suited for larger formats where the "pop" of the sharpness isn't undermined by a lot of visible grain. Ditto, highly dilute D-23, D-76, and HC-110.
It would be interesting to see grain comparisons of PC-512 Borax with Pycrocat-HD[C]. Every time I go off to try a new magic elixer, I find myself returning to HDC.
Going a little off topic, but I've always wondered about whether the 9% water in IPA matters for storage purposes. ( for things you might otherwise preserve in pure ethanol or PG... ) For measuring purposes it makes sense!Phenidone stock solution also works well in 91% isopropyl alcohol -- in North Carolina, that's about $2 a liter at Food Lion. I've used 2%, but I don't know any reason 5% wouldn't also work.
I compared PC-512 Borax with FX-1, blue sky, orange filter.
PC-512 Borax
FX-1
PC-512 clearly gives less grain . An assessment of sharpness seems to depend on whether the relatively smooth edges with PC-512 appear sharper than the ragged but clearly defined edges with FX-1.
The resolution of my scanner ,~80 lppm, is a limitation in the attachments, which are from about 1mm squares of negative.
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