Ilford Ilfostop colour?

[antonroland]

Hello everyone.

I never really bothered with stopbath before as I always do a very thorough rinse but just curious as I got a few bottles from someone for free.

They seem well preserved but at least about 5 years old. The fluid is a bright yellowish orange.

How exactly does the indicator thing work.

If the stuff is too old I might also maybe just as well dump it... :shrug:

Your thoughts?

 

[raathistle]

I believe that when the stop is near exhaustion it goes a purplish colour, immediately obviously not the bright orange it appears when fresh. However, I've never managed to get any to go purple, so normally just disposed of it when I thought about it, normally after a lot of films

I'm like you though, I tend to just use water

 

[TheBigYin]

When the stop is in good condition it's a bright chromium-yellow. As it gets more depleted it turns pink then mauve then purple. The stock solution as it comes from the factory has a shelf life somewhere on a par with Rodinal if kept in a airtight bottle.

 

[freecom2]

I just use water, and never had a problem with it at all. Sorry I can't be more help on the exhaustion colour, but it is meant to be orange - Ilford's technical data:

http://www.ilfordphoto.com/Webfiles/20101131534571533.pdf

Page 3, section 9

EDIT: found out about exhaustion: http://www.ilfordphoto.com/Webfiles/2006130214472102.pdf

"ILFOSTOP contains an indicator dye that is pH sensitive and changes colour from yellow to purple as the stop bath becomes exhausted."

 

[antonroland]

Awesome!

Cheers for the inputs everyone! I was a bit worried that the colour meant it was already unusable.

At 1+19 dilution the bright orange-yellow should fade to a good light yellow so will give it a go.

If I really dig I should find some FP-4 and HP-5 from the early 90's that never saw anything but ID-11 and fixer, apart from copious amounts of water...

Oh well, I have it now, will give it a bash and let you folks know how things progress.

I have one roll of PanF in 35mm that I can develop, shot it in one of my K-1000 bodies with absolute thumb-suck settings.

Will show if anything worthwhile is found, waiting for 5 rolls of PanF 120 to land!

 

[garryg163]

When diluted at this ratio you will have a nice light yellow colour. Under normal (Yellow) safelight it will appear colourless, as it deteriorates you will notice a tone start to wash over your prints as they are agitated, time to bin it. A good mix (1+ltrs) will do hundreds of prints and you can leave it in the tray or re-bottle it as its only acetic acid (Vinegar) I would suggest you do use a stop bath as it arrests the development immediately by counter-acting the alikaline ph of the developer and it will save / extend the life of your more expensive Fix solution.

Gaz