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View Full Version : 4x5 c41 home processing? Advice? Non-Jobo equipment suggestions?



Landrew Gomes
15-Sep-2013, 09:40
Hello all, I felt I should actually use some Ektar 100 & purchase a home c41 kit. First timer c41!

I have a Combi-plan tank that I use for standard B&W development.
Is it wrong to assume constant rotary agitation is necessary to acheive even development with c41?
That being said, looking at one of these in a Patterson tank on a rotary base?
http://www.ebay.com/itm/251333695465?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Unicolor Kit (better alternatives?):
http://www.freestylephoto.biz/10123-Unicolor-Powder-C-41-Film-Negative-Processing-Kit-1-Liter

And one of these to heat up bath for chemistry (not sure what wattage to get, thinking 50w).
http://www.ebay.com/itm/281150355233?var=580214822136&ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

Planning to put all bottles in large bucket, bring to appropriate temp, hand held agitating combi-plan tank. Could it be that simple?

Thank you in advance for any advice.

Ari
15-Sep-2013, 10:13
Could it be that simple?

The short answer is yes.
The long answer is yes, but...
Do a search for the mod54 on this forum, you will find a range of opinions from supporters and detractors.
It is inexpensive compared to, say, a Jobo Expert tank, and therein lies its main appeal.

I have never used the mod54, or the Combi-Plan, but there is no problem processing colour with either of these types of tanks; simply follow the instructions provided with the colour chemicals.

The Unicolor you linked to is similar to what I use, the Tetenal Press kit (developer, blix and stabilizer), and the times and methods for processing vary according to the type of tank and agitation used.
It's all in the instruction sheet; if you don't have one, I can scan mine and post it here.

For heating the chemicals, I use a discarded microwave oven; I unscrew the bottle caps slightly, and zap the developer and blix bottles for 3 minutes on high setting.
You can also place the bottles in a hot water bath, but that takes longer.
I have no idea how well the thermometer you linked to will work.

Search Tetenal in the darkroom section, there is a wealth of information on colour processing at home, and it is as easy as B&W once you adapt to it.

Good luck!

koh303
15-Sep-2013, 15:24
Hello all, I felt I should actually use some Ektar 100 & purchase a home c41 kit. First timer c41!

I have a Combi-plan tank that I use for standard B&W development.
Is it wrong to assume constant rotary agitation is necessary to acheive even development with c41?

It is not really necessary, but it sure makes things easier and the larger your negatives, the harder it gets to have even negs with out proper agitation (rotation or otherwise). As c-41 dev time is usually very short (3:15 mins) every second has a larger impact on your negative then say every send in a process totaling 10 minutes.
Rotary processing, with chemistry introduced while tank is already rotating takes care of some of that.
That said, proper negs (whatever that means anyway) can be had with almost any non rotary processing with enough practice.


That being said, looking at one of these in a Patterson tank on a rotary base?
http://www.ebay.com/itm/251333695465?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

The MOD54 is not really designed to be used on a motorbase with constant agitation (see the many threads here and on APUG on the subject and the MOD54's own instruction videos and tutorials), in short, the tank it self is not really designed for it and a lid popping off the paterson tank will be a real bummer, but you might also run in to dislodged sheets floating around in the tank. Much easier to follow morgan's advice and use his "inversion" system, for color processing (he has a dedicated video for that).


Unicolor Kit (better alternatives?):
http://www.freestylephoto.biz/10123-Unicolor-Powder-C-41-Film-Negative-Processing-Kit-1-Liter

Depending on your volume, a higher capacity/longer shelve life all liquid option might be better, though they tend to be a larger initial investment.


And one of these to heat up bath for chemistry (not sure what wattage to get, thinking 50w).
http://www.ebay.com/itm/281150355233?var=580214822136&ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
Planning to put all bottles in large bucket, bring to appropriate temp, hand held agitating combi-plan tank.
If you are getting good results in BW with your combi-plan then - Sure - why not?

JeRuFo
16-Sep-2013, 04:27
With the unicolor kit hand tanks are specifically mentioned, which is a good thing. I don't know if constant agitation is necessary, but they might be designed with constant agitation in mind. I find a round tank is helpful with constant agitation by hand. I sometimes roll my b/w over a flat surface to get a gentle constant agitation without air bubbles. If you use constant agitation, you can use less chemicals and if you have several rolls/sheets to develop, you could do a few developing rounds and discard the chemicals, so you don't have to store mixed chemicals.

An aquarium heater is probably a good investment, try to get one that is as precise as possible. I often use a bath to get it up to precise temperature, even though I use a Jobo with an aquarium heater type warming element.

As long as you don't have every completely down I would stick with the easier kits, like this unicolor one or the tetenal kit(very easy to use from personal experience). They usually have fewer steps and don't quote as precise a temperature.

koh303
16-Sep-2013, 04:39
They usually have fewer steps and don't quote as precise a temperature.
C-41 has either 2 or 3 steps with universal times.
C-41 is very forgiving, you can be off by several degrees and still get usable results regardless of the kit you use.

JeRuFo
16-Sep-2013, 07:48
Yes, it is a universal process. But they aren't all the same chemicals. Some may be more sensitive to agitation or require a bit more precise temperature control. I mentioned it because the Fuji X-press kit I just opened mentions the developer should be within .15 degrees C. Which is on paper even more precise than E6. Though it probably won't come as close as they state. As with all development processes, repeatability is important. With E6 and C-41 I don't really mess about and usually just build my routine on what the papers say.

polyglot
17-Sep-2013, 17:05
Constant agitation is necessary to get the contrast right. If you don't agitate constantly, you run the risk of colour crossover and/or reduced saturation because you will get slightly less highlight development in each layer, and the effect is likely to vary between film (colour) layers.

There's a C41 howto in the FAQ in my signature that might help clear a few things up.

koh303
17-Sep-2013, 17:15
The C-41 process has lots of tolerance - you can be +/- 1.5-2 degrees and not find any shift even under the most exact testing, regardless of the make and type of chemistry (as long as you are running a standard 38.4 process/time starting point), our C-41 kit will tolerate this and perhaps even more.

E-6 is another story (especially since in most cases the exposure will not be exact enough regardless of how accurate your processing is), but what do you do with slides anyway??

Jim Andrada
17-Sep-2013, 22:36
Re "What do you do with slides?"

Scan them and make great prints!

koh303
18-Sep-2013, 03:44
Negatives are easier to shoot, easier to process, and easier to scan (scanners are not designed to scan slides, not to mention that if you are off by 1/3 of stop you loose a ton of detail). They are also so much more expensive.... So - why not shoot a negative, which will be as sharp, and if you are scanning you can always add as much contrast as you want (though i dont know why you would want to) in post process?

JeRuFo
18-Sep-2013, 04:33
I find scanning positives far easier than scanning negatives, because you can already see what color the scan should have. When I bought my last Velvia 50, it was less expensive than Portra 160. Over here it was 45 euros for 10 sheets of portra and 77 for 20 sheets of velvia. Slides don't work for every subject, but if you have a shot where you can control contrast, Velvia still rules for me.

Deval
8-Apr-2014, 11:58
I've made a DIY home processor for under $100(excluding tank cost). Relatively easy to make. I'm in the process of putting together documentation if anyone is interested

koh303
8-Apr-2014, 15:01
I've made a DIY home processor for under $100(excluding tank cost). Relatively easy to make. I'm in the process of putting together documentation if anyone is interested

I am !!

peter k.
9-Apr-2014, 07:32
So am I ...

Deval
9-Apr-2014, 08:32
Finished the "processor." Heating element coming in today. Will it test out for temperature reliability later this week. Has been used for precise temperature control in many other areas outside of film development so I'm confident that it will hold. Here is a preview pic of the temp control unit. Once I get the documentation together, I start a new thread in DIY or Darkroom when ready.

https://farm4.staticflickr.com/3792/13740015213_678fc475e0.jpg (https://flic.kr/p/mWaaQ2)