Thanks for this really interesting test and putting so much effort on just to show us this.
This hopefully puts end to "developing C-41 in my urine and hair dye gives perfect results every time" myths, combined with the earlier results that lowering the temperature too much really causes crossover and loss of saturation.
On the other hand, this test also shows that crudely wrong processes can give perfectly USABLE results (at least for some people); results that look like color pictures, with some unwanted casts but nothing too serious when the content matters more, or when some unexpected color errors are wanted. The much longer shelf-life of RA-4 developer is a really good argument for this process.
I once accidentally diluted C-41 developer 1+1 by forgetting to drain prewet. At that point, I extended the time somewhat but forgot how much. The result had quite a large color shift that needed filtration not normally used, but when applied, the crossover or other problems were not that evident in "normal" pictures without any side-to-side comparison available.
But, color paper is really a different beast, much more robust. Also, if we suppose that the yellow patch looks odd due to retained silver, then diluting developer 1:4 doesn't seem to have too much effect. However, I'm a bit surprised the ferricyanide bleach did not work that well. I've used it on RA-4 paper with good results. My recipe was 40 g/l ferricyanide, 25 g/l NaBr and bleaching time of around 2 minutes, with very good washes both before and after. Maybe the one you tried is too dilute, lacking bromide or time too short. Also, I don't understand the reason for two-step fixing, especially as the latter step is very short and the first much longer than would be necessary. But then, I understand this is not your process but something random from the internet. Maybe the penny-pitching has just gone too far ? Diluting everything down is not cost saving because you can reuse it less and less, and the process times go up, or the chemicals don't do what they are supposed to, as shown here. OTOH, use strong enough ferri bleach with the correct recipe including bromide, and you can probably reuse it very long and have real savings.
I still don't understand why I should dilute my RA-4 developer. It seems to have practically infinite shelf life as is and it processes an enormous amount of prints per liter. This amount probably goes down with dilution, although it's probably still quite much. Think about dividing infinite by four .
What was not tested was possible dye stability (long-term fading) issues with "alternative C-41" due to the use of wrong developing agent. If it also causes dye hue (absorption spectrum) issues, then the resulting film may "respond" differently to different post-processes (subtractive printing, additive printing, densitometer, different scanners) than normally developed films would. So, even if the hue errors are ok, I wouldn't process any important to-be-archived work like this because of the risk of it fading later on...
Last edited by hrst; 05-08-2012 at 07:59 PM. Click to view previous post history.