Comments from the previous article system:
By Rlibersky - 08:00 PM, 12-13-2005 Rating: None
I found getting Chlorohydroquinone proofed more difficult then I thought. The link above has it on back order. I found some a Fsher Scientific, but they won't sell to the public. I am now talking to some of my freinds that own companies to see if I can order thru them.
By Dwane - 02:53 PM, 12-15-2005 Rating: None
Older editions of The Photo Lab Index (from the 1930's and 40's) suggested that a suitable substitute for chlorhydroquinone was an equivalent amount of hydroquinone and 5% metol. For example, if your receipe calls for 10 grams of chlorhydroquine, you could substitute 0.5 grams of metal and 9.5 grams of hydroquinone instead. So 15 grams of chlorhydroquinone would be equivalent to 0.75 grams of metol and 14.25 grams of hydroquinone. Modifying the Edwal 111 formula would give 5.75 grams of metol, and 14.25 grams of hydroquinone. If you can't measure to the nearest 0.01 grams, you could get by with 5.8 grams and 14.2 grams, or even 6 grams and 14 grams. You might want to give this a try before going through the expense and trouble of finding a source of chlorohydroquinone.
By Rlibersky - 03:06 PM, 12-16-2005 Rating: None
Should be able to this weekend. If I get to I'll report back. Thanks for the information.
By jim appleyard - 11:26 PM, 01-05-2006 Rating: None
According to Steve Anchell in "The Darkroom Cookbook", chlorohydroquinone (I'm going to call it CHQ) is dangerous to make and that any source of it today is suspect. Does anyone know why?
By craigclu - 04:01 PM, 01-15-2006 Rating: None
Did anyone try the HQ/Metol substitution on this yet?
By Zathras - 11:44 PM, 01-15-2006 Rating: None
This looks like an interesting developer. Does anybody know what the dilution would be for a working solution? It looks way too hot to use undiluted.
By Dwane - 10:24 PM, 01-17-2006 Rating: None
According to my copy of Modern Developing Methods for Prints and Fine Grain Negatives, 3rd edition, published by Edwal in 1947, you dilute it with 7 parts water for bromide papers, 5 parts water for fast chlorobromide papers, and 4 parts water for slow chlorobromide and contact papers. Also, Edwal says this developer produces TRUE BLACK TONES, with excellent contrast and detail, and describes this developer as being FOR GENERAL PRINT MAKING.
By Zathras - 06:27 AM, 01-18-2006 Rating: None
Thanks for the info Dwayne. I'm going to give this one a try as soon as I have time to play mad scientist. Mike
By Gerald Koch - 09:01 PM, 02-03-2006 Rating: None
The only remaining commercial developer that I am aware of that contains CHQ is Edwal's FG-7. However, you won't see it listed in the MSDS. This is because it is created in situ during manufacture by reacting p-benzoquinone with hydrochloric acid. I assume this is done because it difficult to obtain CHQ and when one can it is rather expensive.
By Rlibersky - 10:58 PM, 02-13-2006 Rating: None
My brother called today to let me know the CHQ is in the mail. I will finally be able to test this. When time permits I will try both the CHQ and the HQ/Metol substitution to compare. I will get back to you in the forum.
By Rlibersky - 11:51 PM, 02-21-2006 Rating: None
The DOD has FG-7 listed with CHQ on thier MSDS. I have also seen the MSDS that does not list it.
with it listed -
http://hazard.com/msds/f2/bdw/bdwrt.html
with out it listed -
http://hazard.com/msds/f2/bdw/bdwrv.html
Any way I have not found an MSDS for Edwal 111. but I doubt it was required when they stop making it. I now have the CHQ on my shelf. My plan is to play with it this weekend(keeping my fingers crossed)
Edwal 111 
. Either way the formula emitting the Metol works better on old paper then with it.
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