Quote Originally Posted by gainer View Post
I'm posting the comparison that really counts, the one between SPF-3 and Rodinal 1+25. All I have to do now is find where I saved them.
They are "hybrid" photos, using a flat bed scanner at 600 dpi to read 11x14 analog prints. If you print them to 8x10, you should view them from about 6 ft to get proper perspective.
Now, there's a difference! Not like the almost too close to call Microdol-X comparison in the other thread on the 'dead' metol.
I have to say, tho, I've never used Rodinal that strong and don't know if dilution is a factor. The tonality matches but the detail isn't there. SPF-3 looks good to me.

Given the unusual solubility (amount and curve) my idea was to fractionally crystalise out the tetra and leave any more soluble contaminants in the supernatant. I didn't do it in the end. I merely weighed the plastic pots and contents, making a note under them and will reweigh when I need to open another one up for use. This assumes the contents were indeed tetra as stated on the MSDS to start with.
Murray