Chemistry: lith vs traditional

[Marc Leest]

In what does a lith paper developer differ from a normal paper developer, from a chemically point of view ?
I wonder - since lith paper developers are not easy to find - if it is possible to mix it from raw chemicals.

many thanks,

Marc

 

[Nick Zentena]

http://unblinkingeye.com/Articles/Lith/lith.html

Start with that.

 

[dancqu]

I wonder - since lith paper developers are not easy
to find - if it is possible to mix it from raw chemicals.
many thanks,

Nothing to it. I mixed up one a couple of years ago
without even knowing it. If I hadn't left the paper in
the developer for such a long time I'd have never
known. I was testing hydroquinone as a sole
agent developer.

Hydroquinone, sodium carbonate, and a pinch of
sulfite are all that are needed. Those are the same
and only ingredients in Wall's Normal Hydroquinone
Lith developer. That I found out later. Search this
group and from Google for Wall's ..... ..... . Dan

 

[lowellh]

The most obvious difference between Lith developer (designed as a graphic arts film developer) and photo print developer is that Lith chemistry has no accelerator, i.e. metol or phenidone, print developer does. the accelerator makes the developer perform as a continuous tone developer.

 

[psvensson]

I posted some mix-your-own lith formulas at:

(there was a url link here which no longer exists)

(there was a url link here which no longer exists)

They're both works in progress. They're not as easy to use as, say, Kodalith Super RT, but the results are sometimes more interesting.

 

[dancqu]

I posted some mix-your-own lith formulas at:

(there was a url link here which no longer exists)

(there was a url link here which no longer exists)

They're both works in progress. They're not as easy to
use as, say, Kodalith Super RT, but the results are
sometimes more interesting.

They are of the type Wall's Normal Hydroquinone.
I suggest dropping the restrainer. IIRC, my brew used
none. As you know I work one-shot and suggest that
the best way with a Wall's type Lith. Solution volumes
of 1/4 liter or less per 8 x 10 will be easy to work with.
IIRC, 1/4 gram of hydroquinone will do per 1/4 liter.

Have at hand stock or concentrate strength. Dilute
and portion out to tall narrow containers.
Waxed or plastic cups work well. Dan

 

[psvensson]

They are of the type Wall's Normal Hydroquinone.
I suggest dropping the restrainer.

Yeah, I should try that.

 

[dancqu]

Yeah, I should try that.

There is no guarantee of no fog. It's only that I've
run into two or more papers that need no restrainer.
One with the lith which with I experimented. Lately
a bottle of 2% bromide is kept handy and added
as needed. Dan

 

[psvensson]

Ok, I tried without restrainer. I didn't get fog, but the infectious development started too fast. It was hard to snatch at the right time, and the highlights had fairly neutral color. I added some iodide (first time I tried that restrainer) and it worked better, with yellow or red highlights on Forte PWT RC.

 

[dancqu]

[QUOTES=psvensson]
"Ok, I tried without restrainer. I didn't get fog, ..."

No restrainer, no fog. What paper?
Twixt the two of us I'd say we've answered
Mr. Leest's question. Lith developers are
an easy Home-brew.

"...but the infectious development started too fast.
It was hard to snatch at the right time, and the
highlights had fairly neutral color."

Still working with that 1/2 gram of sulfite?
I checked my record of experiments conducted
a couple of years ago. I compounded A and B style.
The A concentrates had a 1:1 hydroquinone to sulfite
or bisulfite ratio; two A concentrates were prepared.
Bisulfite will likely allow for longer lived chemistry.

The B portion, the activator, was left for a sheet
by sheet testing. In a nut shell I went from a 1:1:2,
2 the carbonate, and all between to a 1:1:1, the last
1 being a 50/50 carbonate/bicarbonate blend. You can
read all those ratios as grams and that is literally how
mixed. I'm the guy with the 0.01 gram Acculab scale.

Nice chocolate browns on Arista Graded RC, reds on
Fortezo or an Arista Graded FB; mixed them up. Times,
8 to 24 minutes and that's with no restrainer. I think
even metaborate will work to activate then yield
it's own character and color.

You may wish to play with those ratios some. Sulfite
does slow the rush to and through development. Also
an A concentrate with some more sulfite will last. For
myself and the one-shot minimal solution volume
processing I do, the not so slow oxidation of
the developer in the tray is a factor.

"I added some iodide (first time I tried that restrainer)
and it worked better, with yellow or red highlights
on Forte PWT RC."

From what you've reported and what I've found, I'd
say varying any of the three or four ingredients will lead
to some interesting results. I usually work with graded
but have some 5x7 Kentmere Fineprint and Forte
Polywarmtone; both FB. Maybe I should ... Dan