Film Developing Cookbook, 2nd. ed., and HC-110 syrup minimums

[scheimfluger_77]

In reading through my copy i notice chapter 4 starts off with some developer volume minimums for 80 inches/2 and equivalents.

A) If using HC-110 at 1:31 a minimum of 500ml is specified. Divide that out you get ~16ml syrup/sheet.
B) If using HC-110 at 1:90 a minimum of 1 liter is specified. Divide that out and get ~11ml syrup/sheet.

This is significantly more than the 6ml syrup/sheet minimum specified in the forums and at Covington’s if IIRC, and anywhere else I’ve read.

If I try to develop 6 sheets of 5x7 in my JOBO expert drum this is 1.5L and 3.0L respectively. Either I do fewer sheets/run or split the developer solution and time up in order to stay with workable volumes during the developing step.

What are your thoughts?

 

[DWThomas]

A bit strange -- is there some spec of film format or developing container entangled in this data? Personally, I was shocked the first time I saw the 6ml per 80 in*2 number, as at one time the Covington site said 3ml. After reading that 6 number I went to the site and it said 6, but I had sometime before downloaded a chunk of that site to my local box and at the time I did that, it was indeed 3! I freely admit I have not made any sort of serious study of the matter, and I don't own a densitometer, but I use 1+63 dilution in whatever quantity it takes to fill the tank and see what I think are decent results. Admittedly I don't shoot much 35mm; that in a single roll tank could definitely be stretching the number at 1+63 with a 36 exposure roll.

I suppose one could factor in some worst case scenario where a mostly white snow scene would end up converting most of the emulsion to metallic silver for maximum developer consumption and try some tests. (But I'm retired, old, and lazy! )

Edit: And years back there were apparently two different concentrations of the syrup scattered through different international markets, just to throw in further confusion.

 

[Alan9940]

I've always used the 6ml per 80 sq in minimum and never had an issue with any format from 35mm to 8x10.

 

[MattKing]

The Kodak capacity numbers in the datasheet continue to work out to 6 ml concentrate per 8x10.

 

[138S]

It also has to be pointed that a thin negative requires less developer than a thick one, in theory recomendation has to allow fast/good development of all silver in the film to get DMax in all surface, but usually we only develop a fraction of the silver, so usually we operate with a large safety margin.

There is a test consisting in developing a piece of film open lights with excess developer until DMax, then testing with lower dev amounts until we don't reach DMax or reaching it takes substantial additional time.

Later we experiment with real images with different doses to find time corrections and effects.

Best is following recomendations but being aware of what safety margins we have.

Recommendations try that % of developer exhaustion provocated by dense areas do not have an impact in the other frames in the roll or other areas in the sheet, so it's difficult to exhaust developer.

 

[NedL]

A bit strange -- is there some spec of film format or developing container entangled in this data? Personally, I was shocked the first time I saw the 6ml per 80 in*2 number, as at one time the Covington site said 3ml. After reading that 6 number I went to the site and it said 6, but I had sometime before downloaded a chunk of that site to my local box and at the time I did that, it was indeed 3! .....

Yep, the 6ml minimum was in the Kodak spec sheet for HC-110. The Covington site definitely used to say 3ml, I have it in my notes.
A long time ago I stand-developed a roll of tri-x ( it had been put through Kodak duaflex, and I mistakenly had the shutter on the setting where it's open while the button is pressed... so the exposures were all over the place ) using 2ml syrup in 480ml water for an hour, and it worked just fine.. the negatives were easily printable.

 

[titrisol]

Is it true that HC110 was reformulated recently?
is it still good, or trash?

 

[MattKing]

Is it true that HC110 was reformulated recently?
is it still good, or trash?

Still good - but it is not clear that it will still have the same legendary storage longevity.
I like the new bottles though!