Developer 1:1 Dilution Question

[jrgoresko]

I mixed a batch of Kodak D-76 film developer and was reading about the appropriate times and temperatures and came across 1:1 dilution. Does this just mean that after you make a batch according to the directions given, you can mix equal amounts of that solution with water and use it to develop film with the given adjusted time? I hope that came out right. Someone please confirm or clarify. Thanks.

 

[photoman]

Yes 1:1 dilution would be to take your normal developer and right before you develop your film dilute it with an equal amout of water and use the adjusted time

 

[jrgoresko]

What are the effects of using 1:1? I realize I'd obviously be saving more checmicals, but is there a downside?

-jrg

 

[ksmattfish]

You are not saving more chemicals. When you mix D-76 1:1 the capacity is cut in half for a given amount. What you are doing is slowing down the development time. Developing in a more dilute developer helps get a more even tonal range. The concentrated stock developer gives more contrast.

 

[jrgoresko]

Hmm. Am I missing something? I'm using powder chemicals. I mixed a batch according to the directions on the package. Now, to make a 1:1, wouldn't I be using less of the batch? How don't I save?

I use 10 oz. for 1 reel of film, so would I just use 5 oz. batch/5 oz. water? Or, does 1:1 mean 10 oz. batch/10 oz. water? If so, I realize I don't save chemicals and assume the only reason to use 1:1 is for less contrast?

Do skilled photographers use 1:1 when they know their prints already have a high contrast and want to compensate by toning down with 1:1?

 

[ksmattfish]

If a gallon of stock D-76 is good for X rolls, then diluting it one to one gives you 2 gallons of half strength D-76, and it's still only good for the same amount of rolls. You are using less of the batch, but while the stock solution might still be good for some more developing after being used, the diluted solution would be exhausted quicker and may be a one shot(this depends on how much film you are developing at one time, size of tank, etc...)

Yes 1:1 means equal parts dev and water.

It's not so much that pros use D-76 1:1 to control contrast; most would recommend using it 1:1 because it creates a nicer, more even tonal range. The reason to use the stock solution would be to speed up processing such as for journalism photography; you know, beating the press deadline. Digital has pretty much rendered this moot.

I always recommend using D-76 1:1, unless saving 5 min is really important.

 

[TheProf]

I would agree its always best to do 1:1

If you dilute as you go it will not exhased your stock as quickly. Unless you re-use your developer (which I dont suggest doing unless you cant spare the developer)