Concentrated Rapid Fixer
Rapid concentrated fixer based on ammonium nitrate is one of the most well known chemical receips. To maintain the great resource Silberra FIXER LQ has it is recommended to use stop bath prior to fixing your film or negative. Silberra FIXER LQ is suitable both for film and photo paper.
Sodium thiosulfate, sodium metabisulfite, sodium sulfite, ammonium nitrate.
Preparing Stock Solution (mixing instructions)
Working solution is prepared by diluting the concentrate in distilled water while actively stirring. To prepare a working solution of rapid fixer, it is recommended to use distilled water. Prior to dilution we recommend shaking the sealed bottle of Silberra FIXER LQ concentrate for 20-30 seconds. Stock rapid fixer dilution is 1+4; to prepare extra fast fixer use 1+2 dilution.
Silberra FIXER LQ stock solution fixing time is
3-5 minutes for b&w photo film,
5-6 minutes for baryta based papers,
1.5-2 minutes for RC based papers.
For extra fast dilution fixing time is
1-2 minutes for b&w photo film,
2-3 minutes for baryta based papers,
1-1.5 minutes for RC based papers.
Ideal fixing time for each specific (and/or unusual) b&w film is calculated as triple whitening time. Whitening time is the time unexposed film needs to become absolutely transparent since immersed into fixing solution. Use lab timer and tweezers to get whitening time for a small stripe of unexposed film you're going to fix. Don't forget to triple that time to get real fixing time.
There is no need for additional tests to get fixing time for photo papers: always use the above shown time.
1 liter of Silberra FIXER LQ stock solution can be used to fix up to 25 rolls of film (subject to an increase of processing time for 10% per 3 film rolls) or 40-45 sheets of 18x24 cm photo papers (approximately 2 sq.m.). .
Never use the same working solution to fix photo paper and film.
Keep your Silberra FIXER LQ working solution in a cool, dry and dark place. Keep away from children. It is optimal to store your working solution in opaque, chemically inert and tightly sealed containers with minimal air space in order to reduce oxidation. Strong ammonium scent may indicate that fixer working solution is completely depleted and shall not be used any longer.
Expiry date/ Shelf life
Shelf life for original sealed FIXER LQ bottle is 12 months. Silberra FIXER LQ working solution can be stored up to 3 months past the date of dilution; for partly used working solution storage period is no longer than 4 weeks.
Silberra developers and fixers must be disposed of in accordance with the rules and regulations of the country they are used in. Concentrated developers could be toxic and may harm the environment unless disposed in appropriate manner. Silberra recommends to use special disposal services provided by correspondingly licensed organizations which are eligible for photographic chemistry recycling/disposal.