cyanotype problems

[martin_alston]

I've done cyanotypes many times and they've come out great. I

recently mixed a new batch of chemicals and now I'm having problems.

It seems to take a a long time to wash and the image is fading a lot

while drying. Could to strong of a mixture of ferric ammonium

citrate cause this? I ask because the bottle I have was supposed to

be 100 grams, but when I measured 25 grams it took up way more than

1/4 of the bottle.

[martin_alston]

One other note. I've also noticed the emulsion starting to turn blue before I've exposed.

[group 11]

that does sound like it is the problem, but don't know for sure unless you post the solution a dilution and solution b dilution. as for '...25 grams it took up way more than 1/4 of the bottle...', well, 25 grams is 25 grams; no more, no less. if you use the same ratio that i use (25g/100ml), then 100ml of water is precisely that; 100ml of water. if you didn't begin w/those amounts there could be a problem.

 

is the image fading to gray? are you rinsing in 10% hydrochloric acid?

[martin_alston]

I mixed what I thought was 25 grams with 100ml distilled water. The thing was that what weighed out at 25 grams used almost half of what was supposed to be a 100 gram bottle. I'm not sure if the scale was wrong or if the bottle was wrong. I rinse in straight water. Also, i wouldn't say the image is turning quite grey but something like that. Almost like a faded Van Dyke. I did dilute the solution a little more and it seemed to work better. Still not perfect though.

[group 11]

indeed it does sound like the ferric ammonium citrate mix was too rich. when i didn't calculate correctly, it went to bright green to blue, then to washed out.

 

i keep balloons that have been filled with sand to a variety of weights (1g, 5g, 10g, etc.), then marked w/a sharpie. this gives me a comfort level that my scale is accurate and i use them to zero it when i need it.