How long does diluted fixer last? Answer here..

[MatthewOsbornePhotography]

This is a question I never seem to find a realistic answer to so here is my 2p worth from my own experiences -

http://matthewosbornephotography.wordpress.com/2013/04/30/film-photography-how-long-does-fixer-last

..and a picture for you too


Yuliya, UKraine with ARAX by MatthewOsbornePhotography_, on Flickr

[berraneck]

hi matthew,
you write that you keep film in fixer for 20 minutes. this does not make sense, as the time needed for proper fixing is no more than 6-7 minutes . with stopbath and rapid fixer, 4 minutes can be enough.
next thing about fixer lifetime - it is hugely prolonged when using stop bath and if stored properly (airtight, dark bottle in constant ambient temperature). anyway, nice picture;)

[MatthewOsbornePhotography]

Re. http://matthewosbornephotography.wordpress.com/2013/04/30/film-photography-how-long-does-fixer-last

Thanks for your very valid comments and thoughts. Glad you liked the photo

The reason I use a fixing time of 20mins is:

1) I rather play it save and have pictures rather than no pictures.
2) I realise I am probably using fixer far longer than I should so I think that if less active components (as some exhauted with previous films) I need to leave it to fix for longer
3) I rarely agitate. I do 2 or 3 turns at the start to ensure no bubbles and that's it. The fixer next to the film therefore in theory works to exhaustion therefore leaving for a longer duration is safer.

I realise it is a wacky method but stand fixing and stand developing suits my lack of free time well so I can then spend any time I do have taking photos.

I will paste more blog post links when I describe my developing methods soon if interested.

[iangreenhalgh1]

I tend to leave films in the fixer for a while, I'm forgetful sometimes. I keep the fixer in a 2 litre plastic bottle, been using the same batch for nearly 6 months now, it still works fine. I don't worry about it because if something isn't fixed enough due to exhausted fixer, just mix up a new batch and fix the film again, done that a few times, never had an issue, touch wood.

[berraneck]

matthew, I am glad you´re sharing your experience, however without proper explanation it´s quite confusing for newbies. 20min stand fixing is not better than 5min fixing with agitation. when using exhausted fixer, prolonging fixing time is not 100% reliable solution. I don´t understand this, because price of homemade fixer is just funny cheap.

[MatthewOsbornePhotography]

[berraneck]

http://www.jackspcs.com/tf2.htm

approx. £2/liter

[ForenSeil]

Ammonium thiosulphate based (=fast) fixers are more harmful to the silver in the emulsion than sodium thiosulphate based fixers, if the films stays too long in the fixer.
If you wan't to go safe/use long fixing times, you should take an sodium thiosulphate based one

(or make your own fixer from pure sodium thiosulphate and destilled water - it's cheaper anyway).
You can find it dirt cheap on Ebay etc. and often as chlorine killer in hardware/pool stores etc.
http://www.ebay.de/sch/i.html?_odkw=%28sodium+thiosulphate%2C+natrium+thiosulfat%29&_osacat=0&_from=R40&LH_PrefLoc=2&_trksid=p2045573.m570.l1313.TR0.TRC0&_nkw=%28sodium+thiosulphate%2C+natriumthiosulfat%29&_sacat=0
Pure crystalline thiosulfates does never get bad as long as it's stored in darkness and sealed from air.
Sodium thiosulfate fixers aremore stable in solution than ammonium thiosulphate fixers but both are pretty stable if stored airtight.