Rolf-Werner
I fancy doing some colour photography again. I’d be developing in a drum.
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There’s a set from ADOX and one from Tetenal on offer here. Are both sets suitable for this? The Tetenal one says it’s for machine processing. Is that why it’s called ‘Rapid’? Is the ADOX equivalent or better for drum processing?
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Perhaps someone knows both from experience, so thanks for any tips!
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Rolf
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Rolf-Werner
Hmm. Does nobody know, or are you all already caught up in the Christmas rush? :rolleyes:
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Rolf
Wolf_XL
Have a look...
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http://www.ars-imago.ch/pdf/auto/ars-imago-000176.pdf
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or
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https://www.macodirect.de/media/pdf/TCR15K_datenblatt_d.pdf?
– Hopefully that link won’t blow up Mirko’s server... ;-)
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ADOX chemicals explicitly state
: “Processing should be carried out at 35 degrees Celsius. The development and fixing times are then 45 seconds each.”
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The chemicals don’t mind whether you use a drum or a machine – as long as the temperature is kept more or less constant.
Rolf-Werner
The second link doesn’t work. But thanks anyway for the first one. So that means that if I want to develop film by hand in a drum at room temperature, I need to find the Tetenal chemicals designed for that purpose. Is that right? And they’re not available here, because the kit on offer is designed for 35 degrees.
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Rolf
Wolf_XL
...as far as I know, there is no longer an RA-4 process that produces satisfactory results at room temperature. I suspect that, due to a lack of demand, it was no longer worth the effort.
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The link should now work:
https://www.macodirect.de/media/pdf/TCR15K_datenblatt_d.pdf
Rolf-Werner
Ah, great, that means we can work with a temperature of 30 degrees as well; that makes it much more feasible.
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Thanks for the link!
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Rolf
Wolf_XL
...it is also possible to run a high-temperature process without temperature control. Back in the day – when everything was better – there used to be a colour process developed by FTK Kleinschmitt, later marketed as Dilucolor and Diluprint.
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The procedure was as follows:
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The chemical solution was poured into the drum at 38°C; after one or two minutes (I can’t quite remember exactly), the temperature was measured. The measured temperature was then used to determine the remaining development time with the aid of a table.
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In principle, this is quite logical – since, on the one hand, the product of temperature and time must always remain constant for correct development, and on the other hand, cooling occurs linearly in relation to room temperature – in other words, the extension factor is directly proportional to the cooling per unit of time... The cooling constant effectively gives you the extension factor...
jonny
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It is true that there is no longer a kit explicitly advertised as being for ‘room temperature’. However, that does not mean it would not work. The Kodak Ektacolor RA chemistry, for example, works perfectly well at 35, 30, 25 and down to 20 degrees. The downside is that it comes in larger containers of 5 litres or more. A slight adjustment to the filtration is necessary. I cannot comment on other chemical kits due to a lack of experience.
jonny
Gast
This thread is a bit old, I know. Still, I’m using it because of the apt title.
Could it be that the range of RA4 chemicals is starting to dwindle?
According to Maco, Digibase RA4 is no longer available, and here at FOTOIMPEX the ADOX RA4 kit hasn’t been available to order for some time.
Both still have the Tetenal kit in stock.
Is this a temporary issue, or has the EU banned certain chemicals again, meaning that ‘only’ existing stock is now being sold?
Why aren’t there any powder solutions in the RA4 range that have a longer shelf life?
MirkoBoeddecker
There is further consolidation taking place on the supplier side (raw materials). The EU has nothing to do with this. Whilst we are seeing a revival in the market, prices for all analogue products remain so rock-bottom that any sensible businessman would shake his head and walk away. Idealists like us do it anyway and earn our money elsewhere or not at all, but when it comes to the larger producers in the chemical sector, these are often companies that can do something else as well. It’s a case of make or break. If a product doesn’t yield a certain minimum return so that costs can be covered, then it simply isn’t manufactured any more.
We could produce it ourselves, but it’s not worth it. So what Tetenal currently offers is actually quite good. If that ever stops, we’ll be there.
Gast
Well then, I’ll just have to use Tetenal. It’s just a shame that I’ll end up throwing half of it away.
Can you freeze some of the chemicals?
Sandro
I can't tell you that right now, but I've actually thought about freezing it before too.
Magirus
That shouldn’t work – it messes up the chemicals. You should have a googling.
(I read something about it, but it’s not the final word...)
Have you ever tried Tetenal as a single-use developer?
The original chemicals stay pure and have a longer shelf life.
Regards, Bernd
Wolfgg
I’ve already successfully frozen E6 and C41 developers as a working solution at -18°C; they last for at least 12 months. RA4 isn’t that different, so there’s a good chance it’ll work here too. So don’t hesitate – give it a go (but not with glass bottles).
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Regards, Wolfgang
Gast
That’s not supposed to work – it messes up the chemistry. You should have a googling.
(I read something about it, but it’s not the final word...)
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Since I won’t be using up the whole kit anyway, I’ll just do the frost test with a small batch. I can then report back here on what the results were.
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Have you ever tried Tetenal as a single-use developer?
The original chemicals stay pure and have a longer shelf life.
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I only make small batches anyway; I don’t need a whole litre for the drum.
HenningH
There was once a test in *Hobbylabor* magazine on freezing chemical kits, and the paint kit was the only one that didn’t break when frozen.
Rolf-Werner
I’d be interested to know that too – why freeze the batch rather than the original chemicals? It’s a much smaller volume, after all. Our freezer’s already absolutely packed :)
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No, seriously, if I know I always need the original chemicals for a 500 ml batch, I can just freeze the appropriate portions. Unless there’s some technical reason not to...
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Regards
Rolf
Ewald
The second link doesn’t work. But thanks anyway for the first one. So that means that if I want to develop by hand in a drum at room temperature, I need to find the Tetenal chemicals designed for that purpose. Is that right? And they’re not available here, because the kit on offer is designed for 35 degrees.
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Rolf
I always use Tetenal, and process at 35°C in open trays or, for formats 25x30 and larger, in the Jobo drum. At lower temperatures, I can’t achieve consistent, colour-accurate prints.
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Horst
Wolfgg
Rolf-Werner:
If you freeze the original chemical solution, precipitates may form which are difficult or impossible to redissolve once thawed. Just think of substances that have to be dissolved in a specific order so that they all dissolve. This is probably why Kodak always specified a minimum temperature for many concentrates (e.g. +5°C for E6). But here too, the saying ‘practice makes perfect’ applies.
Of course, it’s also more convenient and quicker to simply take the bottle for one film out of the freezer, defrost it and bring it to the right temperature, and you’re ready to go. Even dilution errors can’t happen this way. These can easily occur when you’re reading the measuring cylinder after a long photo shoot, tired and hungry...
Regards, Wolfgang
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