Tetenal C41 Developing

<p>I am using Tetenal's C41 (1 Liter) kit for my first time developing colour neg film in a standard developing tank and have a few questions.</p>

<p>The instructions say to mix up the full liter and develop as follows:<br>

First 1 to 4 films for 3 minutes 15 seconds<br>

Next 5 to 8 films for 3 and half minutes<br>

Next 9 to 12 films for 3 minutes 45 seconds<br>

Next 13 to 16 films for 4 minutes</p>

<p>I presume this means I can develop up to four films together and re-use the developer another three times? But if I only develop 1 or 2 films each time, will I still only get four development runs out of the kit and therefor not get as much value?</p>

<p>Is it ok for example to only mix up half the kit if only doing two rolls at a time? This way I could increase the capacity and still get sixteen rolls in total.</p>

<p>What agitation is required?</p>

 

<p>You can develop one roll at a time, and still use those compensations for the developer wearing out.<br>

Your real challenge is using all 16 rolls worth in the limited lifetime of the kit.<br>

A powder kit must always be mixed entirely at once.<br>

If it's the liquid kit, you still have the problem that one part of the developer is probably back-filled with nitrogen gas at the factory, and once you open that bottle and let oxygen in, you've set off the "time bomb". C-41 developer is <em>very</em> sensitive to oxygen.</p>

<p>The development time is based on how many rolls have been through the chemicals, not how many are in at one time. You could do one roll at a time four times, for example, before you would have to jump from 3:15 to 3:30.<br />You do have to mix all of the kit at once to ensure that everything is mixed properly. That does not affect the number of runs -- you could do 16 rolls all in one run if you have a tank that big and that many reels, or you could do 16 runs of one roll each.<br />Once mixed, the chemicals are only good for about a month at most, so John is correct that getting your money's worth out of it before the chemicals go bad is the challenge. But the kit is only about $20. if your local lab charges, say $5 for develop-only without any prints or scanning, you would break even at four rolls and be ahead of the game for anything beyond that.</p>

<p>I have had Tetenal C-41 'kits' last 18 months and develop over 24 rolls with great results. Cool dark storage helps.</p>

 

<p>Thanks for the replies.</p>

<p>The instructions do not mention agitation. Should it be every 30 seconds or every minute and do I turn the tank up side down as I do for B&W?</p>

<p>Also it recommends pre-heating the tank but should the film be pre-washed also or is there any need to do this?</p>

<p>Don't know exactly what your setup is, but I use a stainless steel tank in a water bath to keep the average temperature during development at the required 100 degrees F, and use inversion agitation every 10 seconds throughout development. I do not use a pre-wet and get excellent results. YMMV. Test your process before doing anything important.</p>

<p>Curtis, the instructions should say 102 degrees (Fahrenheit), agitate for ten seconds every thirty seconds. Total development time 3 1/2 minutes, adjusting as previously noted as the more rolls you do from the same batch. You can get a full set of instructions on Freestyle's site here: <a href="http://www.freestylephoto.biz/static/pdf/product_pdfs/unicolor/unicolor-c-41-powder-1-liter-instructions.pdf">http://www.freestylephoto.biz/static/pdf/product_pdfs/unicolor/unicolor-c-41-powder-1-liter-instructions.pdf</a> They are the same instructions for Tetenal, Unicolor, etc. They are all the same basic kit just rebranded. </p>

<p>I have been using this kit since the beginning of the month and just developed my 5th roll. The 4 previous rolls i used the recommended developing time of 3 min 30 seconds and blix at 6 min. For the 5th I used 3min 45 sec and blix at 10min. Is that going to work for the next 2 films? Then increase to 4min for films 9-12. But what about films 13-16? Should that be at 4min and 15 sec or will it be exhausted by then? I am confused because it doesn't go that much into depth and I haven't found a straight forward answer online. Thanks</p>

<p>I am always fascinated to hear how many rolls of film people get out of these kits. I am surprised by the comments that they only last about a month. I mixed a kit last October (5 months ago) and it is still working. Last night I developed roll number 42. I've heard of people getting over 50 rolls out of a kit. Of course, eventually quality is going to degrade, but I honestly haven't seen that yet. The key, as mentioned above, is storage. I store mine in brown plastic lightproof bottles, in a dark closet, away from sunlight. I also make sure to get as much air out as possible before I put it in storage. </p>