rlfsoso
Hello everyone,
I’m getting my darkroom up and running again and am thinking of trying selenium toner with the prints I’ve made so far. Having read through various posts, I’m not quite sure how to go about it:
The literature usually recommends a combination of selenium toner and hypo clearing agent. Presumably to adjust the pH level (!?). Does combining Lavaquick with the selenium toner make sense? Unfortunately, there isn’t much information available about Lavaquick, apart from the fact that it is said to increase the density of the prints slightly on its own.
I’ve got hold of some Rollei LP-Selenia. I realise that, above all, I need very well-retouched baryta prints as a base, which should be thoroughly rinsed again before toning if necessary, then toned by eye (in the open air) and washed thoroughly. Are there any other important practical tips?
Many thanks,
Rolf
Otto
Using a combination of selenium toner and HCA saves you a bath. This only makes sense if you have a high throughput, as the mixture doesn’t keep as well as the individual ribbons.
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Best regards,
Otto!
rlfsoso
Thanks for the info – I’ll use Lavaquick before draining it out then.
Best regards, Rolf
Otto
There is a detailed data sheet for the toner mentioned:
http://www.maco-photo.de/files/images/TASel_d.pdf
It is important to use a neutral fixer wherever possible. In that case, a quick rinse before toning is all that is needed. This saves time and water.
As already suggested, a washing aid is also highly recommended. A homemade solution is simple and effective:
http://www.fotografie-in-schwarz-weiss.de/sw-fotografie/tipps-tricks/69-waschhilfe.html
Good luck and best regards,
Otto!
gerich
When preparing HCA yourself, bear in mind that it must contain EDTA 4Na salt and sodium citrate, as otherwise calcium may precipitate, leaving white streaks on the paper. My procedure for selenium toner is as follows:
2-bath fixing in C-41 fixer, adjusted to a pH of approximately 6 by adding a little acetic acid.
Intermediate rinsing. Collecting the prints in a water tray and rinsing them again is sufficient
Toning at approx. 28°C, 1:20, 4–7 mins (an old lab partner’s toner, which was even more concentrated)
Brief rinsing
HCA 3–5 mins. I prepare it myself; the approximate recipe is: approx. 120g anhydrous sodium sulphite, approx. 25g sodium metabisulphite, 5g EDTA 4Na, 5g sodium citrate. I prepare the toner and HCA with distilled water.
Wetting for 1 hour
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I bought sodium selenide to prepare the toner myself, but I’m currently held up by the second most common chemical after water, namely ammonium thiosulphate, which I’ve so far only been able to find at prices, or in larger containers from 25 kg upwards, that are in the same range as hydroquinone. My ammonium thiosulphate had decomposed and already smelled of hydrogen sulphide. If anyone has too much ammonium thiosulphate that is still in good condition and would like to swap, I have too much of the following chemicals: sodium metabisulphite, hydroquinone, phenidone A, sodium selenide, sodium acetate, pyrogallol, phenylmercaptotetrazol.
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Best regards
Gerhard
jochen53
Hello,
Ansel Adams also always performed dilution of KRST with HCA. However, in his book he also writes that Kodak pointed out to him that this offers no demonstrable advantage. For the sake of completeness, I would like to point out that sodium selenide is extremely toxic (particularly if dust is inhaled) and, when combined with acids, produces highly toxic hydrogen selenide H<sub>2</sub>Se, which has a foul odour. Toners such as KRST and similar formulations do not contain sodium selenide Na<sub>2</sub>Se, but rather sodium selenite Na<sub>2</sub>SeO<sub>3</sub> (which is also highly toxic). KRST contains 27% ammonium thiosulphate, 10–15% anhydrous sodium sulphite and 2% sodium selenite (source: Kodak MSDS).
gerich
Of course, it was sodium selenite, CAS 10102-18-8, that I had mistakenly written down; thanks for pointing that out.
Another observation regarding Selentoner. If I leave the used Selentoner from my lab partner sitting in the container for about 1.5 weeks, selenium starts to precipitate, initially as a reddish-brown film on the sides, and later as a black deposit at the bottom. I assume this happens when the sulphite has been consumed by atmospheric oxygen. Simply adding more Na sulphite doesn’t work, because it doesn’t dissolve completely. What does work, however, is dissolving approx. 20 g of Na sulphite in 250 ml of distilled water, to which approx. 1 g of EDTA 4Na has been added beforehand, and then adding the solution to the toner. I haven’t yet tried whether the used toner then lasts significantly longer. The precipitation of selenium can also be used for disposal by allowing it to precipitate, then decanting the liquid and discarding it.
Best regards
Gerhard
