Another HC-110 question

[Doc W]

Take a look at the Kodak Datasheet (p.7) on HC-110. It lists the various dilutions and their capacity in terms of 1 litre in a tank without replenishment.

One litre of dilution A (1:15 from syrup) can develop ten 8x10 sheets. Each litre of dilution A contains 62.5 ml of syrup, so one sheet requires 6.25 ml of syrup. This is the same for the other dilutions (except F). One litre of dilution B will do five sheets, with a total of 50ml of syrup and, again, 6.25 per sheet. And so on, with dilution E being slightly different (6.9ml per sheet)

Then we get to dilution F which has 12.5 ml of syrup. One would expect that this could do two sheets but it is "not recommended" even for one sheet.

Does anyone have any ideas why?

 

[Photo Engineer]

You can get so dilute that the pH and movement of chemicals becomes limited. In that case, development goes down as the developer is used or "seasoned in".

PE

 

[MattKing]

Probably related to the reason that there is no official dilution "H" - past a certain point the effects of dilution become increasingly non-linear.

Note as well on the next page where storage life of working solutions is listed that storage of working solution dilution F is not recommended.

 

[Vaughn]

...Note as well on the next page where storage life of working solutions is listed that storage of working solution dilution F is not recommended.

Off the top of my head, that may due to the amount of dissolved oxygen to the amount of developer is too high with such high dilutions. But I might just be having a brain-fart.

 

[Gerald C Koch]

Read the following article for information on HC-110. It makes the point that "development time is roughly proportional to dilution." HC-110 contains about a dozen chemicals. When you dilute it there occurs a dozen separate reactions. It is perhaps a bit naïve to expect anything like a linear relationship to be maintained.

http://www.covingtoninnovations.com/hc110/

 

[Doc W]

Thanks a lot for the replies. I am trying to find a developer that will allow me to develop from N-2 to N+2 in my Jobo. I have to increase the dilution to get a minimum development over 5 minutes, but I get odd results with dilution F in this situation and I think I just found out why. I wonder if D76, which has similar qualities to HC-110 would allow me to get a full range of N+ and N- densities.

 

[Bob Carnie]

I just got a quote of $45 per bottle, for largish volume, I was quite surprised,and am looking for better price.

 

[bvy]

You might be happier with XTOL for Jobo/rotary processing. HC-110 under constant agitation seems to produce a very contrasty negative -- i.e. density builds quickly and shadow detail suffers. My experience, anyway.

 

[Bob Carnie]

I was using this dev for Ortho 25 film exposed in laser, so I am not sure if xtol will work, I am mixing up lots of chemistry and developing in large tray.

 

[Gerald C Koch]

I just got a quote of $45 per bottle, for largish volume, I was quite surprised,and am looking for better price.

If you use it at dilution E or as I do 1+49 (a bit easier to calculate in ml) then it works out to be less than a dollar per litter. The price is not too bad when you look at it this way.

HC-110 can be used in a self replenished system.

 

[Bob Carnie]

If you use it at dilution E or as I do 1+49 (a bit easier to calculate in ml) then it works out to be less than a dollar per litter. The price is not too bad when you look at it this way.

Yes you are right , I will consider this when setting up my trays.

I know a lot of chemical formulas have been put out there for scratch mixers, was HC110 ever one ?

 

[Gerald C Koch]

Yes you are right , I will consider this when setting up my trays.

I know a lot of chemical formulas have been put out there for scratch mixers, was HC110 ever one ?

No. HC-110 is rather unique as it is made without water. All the constituent chemicals are dissolved in a mixture of glycols. Without any water present inorganic salts like potassium bromide cannot be used (they are insoluble). Therefore Kodak had to use various adducts such as diethanolamine hydrogen bromide. These would be difficult or impossible to obtain by the customary user. Kodak had to manufacture some chemicals in house.

 

[MattKing]

Remember of course that the current bottles are more than twice the size of what they were historically.

 

[Bob Carnie]

Remember of course that the current bottles are more than twice the size of what they were historically.

do tell