what does c 41 Bleach starter do

[DJ_Zio]

For developer, that's what I do. It's also crucial.
However, for bleach, fix and blix (RA4), I generally don't. It's not really necessary (or rather: really not).

If it's "not necessary", then why do they manufacture it? It's 100% necessary for C41 developer and bleach and RA4 developer and bleach-fix *IF* mixed from replenisher concentrate. If you don't you're doing it wrong.

 

[koraks]

If it's "not necessary", then why do they manufacture it?

Ask Fuji. Fact of the matter is that it works fine. It's not necessary in a home setup.

Btw, color blix and fix often have no starter; the replenisher is identical to the fresh tank, and/or the fresh tank is simply the replenisher, but a little more dilute. It depends on the chemistry.

Bleach uses a starter but it's also based on the fact that in a commercial processing line, there's no stop bath and the carryover of the developer will affect the bleach pH. Moreover, bleach times in a commercial process can be short to the point of barely sufficient, which means the bleach must be working at the highest possible speed. In a home setup, you can easily bleach longer and account for the difference. In practice, it turns out the leaving out the bleach starter makes no difference. It works just as well, but it's one less chemical to purchase.

If you don't you're doing it wrong.

Life's too short for dogma.

 

[KyleMika]

I am planning on not adding the bleach starter to my Flexicolor Bleach even thought until now I have always done it. My main reason here is that my bleach starter has expired (its odd that this is the only chemical other than the developer starter that has an expiration date on it) and photo sys seems to have yet to start selling Kodak Flexicolor chems again, so I am trying to last this year without new chems that currently do not exist. My developer starter has also expired ~9 months ago, but I don't see the harm in using this.

 

[koraks]

My developer starter has also expired ~9 months ago, but I don't see the harm in using this.

Developer starter is mostly/only potassium or sodium bromide. It won't go off; no worries.
The bleach will work fine without a starter. I replenish my bleach, which means that it's "started" anyway after a couple of uses. Never noticed a difference between fresh replenisher bleach and seasoned bleach.

 

[KyleMika]

Developer starter is mostly/only potassium or sodium bromide. It won't go off; no worries.
The bleach will work fine without a starter. I replenish my bleach, which means that it's "started" anyway after a couple of uses. Never noticed a difference between fresh replenisher bleach and seasoned bleach.

Great, thanks for the reassurance! Hopefully Photosys gets their act together before I run out of LORR Developer, at least I have enough bleach and fixer concentrate to last years, but it would be nice to have the bleach starter available, even if it seems to have no effect.

 

[lamerko]

Whether or not a starter is required depends on the formula itself. Here's how Fuji's chemistry works:

 

[foc]

Many years ago I had to mix fresh tank of C41 Bleach from Fuji CN 16s chemicals cartridge and Fuji had no Bleach starter.

Worked just find. Just like the time the film processor Bleach heater failed and I had to wait 5 days for a replacement. Bleach tank worked at 31C with improvised heater, again not ideal but very workable.

C41 can be very forgiving except the developer.

 

[Mr Bill]

If it's "not necessary", then why do they manufacture it? It's 100% necessary for C41 developer and bleach and RA4 developer and bleach-fix *IF* mixed from replenisher concentrate. If you don't you're doing it wrong.

Hi, I would say that you are pretty much correct, strictly speaking. Kodak originated the C-41 process so I would say that they are the authority on exactly what the chemical specs should be. So if one does not conform to said specs, within the tolerances, well then, they have an out-of-spec process. (I should say that "behind the scenes" such specs exist, but not available to the general public.)

But for practical purposes the "performance" of a C-41 process is generally evaluated by the actual processing of film, typically represented by the use of so-called "process control strips." (These are pre-exposed test strips, supplied by the manufacturer, which the lab will process and compare to a correctly-processed reference strip.) So if the processed results - the only thing that a normal customer will see - are within tolerances, most people would say it's OK.

It's possible to have C-41 bleach and fix be WAY out of chemical specs without any visible effects on the film. So... I'm guessing it probably happens a lot. And it probably doesn't make much difference for non-professional use.

 

[halfaman]

When I started to use Fuji Hunt MP60 RA4 developer I used it for several months at 35º C like my previous chemistry. After several months I noticed that the datasheet specified 38º C... I changed the temperature and repeated some prints without seeing anything different.

I try to work "by the book" in color processes but I fell also that C-41 and RA-4 have some flexibility.

 

[koraks]

I changed the temperature and repeated some prints without seeing anything different.

Yeah, makes sense. It's a develop-out process in the end.