thats' the stuff ... I'm not how much cheaper someone can get sodium hydroxide for ... or if it is worth the trouble.
that crystalized stuff couldn't be easier to use, I just pour the recommended amount of water into a tray, dump in the packet, and slosh it around till the crystals are gone
i quickly developed eight boards with one batch, and could have done more but the mixture starts getting cloudly with all the resist it has dissolved, so at 50 cents a mix, just toss it out and start fresh
regardless of what developer you use, it must be agitated - anyone claiming otherwise, well, they're just really lucky
as far as exposing the pcb for an hour ... my goodness that's overkill or the light source is really weak ... seeing as how the pcb itself is the most expensive part of the operation, it's worth the investment to buy a cheap fluorescent light or incandescent "painters light" (just a socket with a cord, a cheap aluminum reflector and a flimsy clamp) - it'll last virtually forever and yeilds excellent results
with phototransfer and my method (fluorescent, crystal developer, ferric chloride etchant) I routinely make boards with all sorts of SMT pads, traces down to .0120 inch (12 mills or 0.3048 mm)
here is an example of the results I get:
on the left is a pcb with 12 mil traces, next to it on the right is a board with 24 mil traces ... these have been banging around in a drawer for a bit, so the resist is scratched a bit.
**broken link removed**