In trying to “perfect” EXB, I finally started doing proper note taking and making a progression of prints and seeing exactly what ingredient additions on the print has, as well as trying a few different papers. Previously I was taking rough notes and kinda just faffing about to see what my subjective opinion was on each new print. So, I’m going to try doing this post a bit different, with a literal progression of my prints and the modifications made with each one. Each print (excluding cooltone/133) had a print time of 8s, f/8, and target snatch point was when the tower in the background was a bit beyond grey and getting into infectious black. Each scan was adjusted carefully for color accuracy and black depth
The base formula here is EXB7:
2L water
15ml HQ-TEA 20%
2ml Phenidone/Propelyne glycol 0.1%
10ml potassium iodide 10%
50ml sodium sulfite 10%
1ml potassium bromide 10%
20ml benzotriazole 2%
80ml sodium hydroxide 3%
Final pH ~12.5
The first print had significantly too much highlight development and I didn’t keep nor scan it. I added 20ml of benzotriazole and then made this print:
Ilford Warmtone RC, “exb7b”
With this it looked decent, but I wanted deeper blacks and more shadow separation. I added 5ml of potassium bromide.
Ilford Warmtone RC, “exb7c”
This did seem to help tonal separation some as well as increase black levels (probably due to being capable of keeping the print developing longer), but the changes weren’t too significant, and still wasn’t resembling the poorly documented success I had with EXB4. I decided to add 1ml more phenidone mostly just to see what would happen and if previous experiments were correct.
Ilford Warmtone RC, “exb7d”
The results were measurably worse for tonal separation as well as for black depth, probably because it then couldn’t be left in developer as long as previously. Next time I’ll probably opt to start with an even smaller amount of phenidone, like 0.5ml of 0.1% solution. However, since this developer still had plenty of life, I decided to see how it’d treat other papers. I then did Fomatone 133 FB paper (a known “mostly lithable” modern paper) and it produced really nice results. (note exposure and snatch point are different here)
Fomatone 133 FB, “exb7e”
I then tried Adox MC112 FB paper. The results were so bad I didn’t even bother rinsing after fixing. The emulsion had pinholes in it and infectious blacks never came through. Then I decided to try Ilford Cooltone RC. It never went into infectious development so it’s extremely low contrast
Although less complete and granular of a series, I’ll also share a few prints from EXB6 testing
EXB6:
2L water
15ml HQ-TEA 20%
2ml Phenidone 0.1%
20ml potassium iodide 10%
50ml sodium sulfite 10%
1ml potassium bromide 10%
10ml benzotriazole 2%
65ml sodium hydroxide 3%
final pH ~12
Warmtone RC, exb6a
With this, things were too eager to go infectious, so I added 10ml of benzotriazole and also 10ml of hydroxide
Warmtone RC, exb6b
And then finally for some reason decided to add 0.5ml of phenidone
Warmtone RC, exb6c
Then I tried slowing down highlights etc more and get deeper blacks and added 10ml of benzotriazole and added 20ml of hydroxide
Warmtone RC, “exb6d”
Afterwards I tried a number of other modifications, especially with additional iodide and hydroxide and all were failures at getting deeper blacks while slowing down highlights.
Overall, these are the things I think I’ve learned:
Too much iodide eventually will lighten blacks
Magic lith developer formulation seems quite easy if sticking to only a single type of paper.. But the failure here with cooltone RC was especially surprising. Maybe it’s not possible to make an ideal lith developer that works on every paper. You can only make either a mediocre universal developer, or a great specialized developer.
Adox MC112 is the devil
Too much benzotriazole can harm the delicate highlights of lith
Keeping this developer very alkaline definitely makes it fast, but brings with it other problems. Ideal for keeping a differential development rate is somewhere around 12 and definitely less than 13.
Too much phenidone also makes blacks less deep and can cause lower midtones to enter infectious development earlier than desired. Ultimately there is definitely a minimum and maximum range, but ideal range is subjective. I prefer for lower midtones to be untouched until blacks are really deep, but this definitely isn’t a universal “best” thing.
Despite the problems, this is a very stable lith developer. I decided to leave EXB7 alone for a couple hours and when I came back it was a pale brown and seemed to still have enough life for more printing.