Kodak RA/RT Usage Advice (Replenishment)

[peoplemerge]

Next to my enlarger is a drum scanner, and have a "pure sine wave" battery backup by tripp-lite or APC. I've always wondered if it would be a legitimate use of the device to use it to filter the power supply for the enlarger as well.

 

[NortheastPhotographic]

I'm going to hopefully start printing RA4 this week and I picked up the Kodak 10L kits for Dev and Blix. Just trying to plan my bottle set up.

I'll be using a Nova 12x16 unit that doubles as a B&W processor since my space can run a little bit cold here in Maine, so keeping the working solutions in the tanks at all times is not possible. As per the instructions I could mix up 2L of working solution, then drain after a session into a 2L bottle. But then I need to mix up my replenisher... So I could just have either an accordion bottle for the repenisher and mix it 1lt at a time. Or I could be fancy and get a 2 gallon floating lid container with a spigot. That's what I do for my XTol R solution.

Man how the bottles do add up...

 

[Bumba]

I'm going to hopefully start printing RA4 this week and I picked up the Kodak 10L kits for Dev and Blix. Just trying to plan my bottle set up.

I'll be using a Nova 12x16 unit that doubles as a B&W processor since my space can run a little bit cold here in Maine, so keeping the working solutions in the tanks at all times is not possible. As per the instructions I could mix up 2L of working solution, then drain after a session into a 2L bottle. But then I need to mix up my replenisher... So I could just have either an accordion bottle for the repenisher and mix it 1lt at a time. Or I could be fancy and get a 2 gallon floating lid container with a spigot. That's what I do for my XTol R solution.

Man how the bottles do add up...

Hey Northeast Photographic. I'm not expert but from what I've read, I'd stay well away from accordion bottles. The walls are thin and you can't get all the air out fully so you would run the risk of oxidation of your developer. The bottles are good in theory but bad in practice.

I've been using those clear wine bags that I just bought online. I was skeptical at first but wow they are amazing and so cheap. Pros: bag collapses in on itself and the tap on it allows easy and accurate liquid dispensing. Negatives: the smallest bags are 3 litres so if you're only making 1 litre of replenisher then it's can be a right pain in the ass to get all the oxygen out of the bag when your putting the tap/spigot in. It's not so bad with a full bag of 2 or 3 litres but it can imagine it being fiddly with a small amount.

One more thing I've noticed is that the paper can soak up a sufficient amount of developer. This means after your printing session you'll have a but less that when you started. For this reason I'd say store working solutions in plastic bottles so you can get rid of the air, glass bottles with a handy supply of marbles or lastly just replenish as you go along or at the end of the session to top up the bottles.

Also one last thing (don't want to overload you) everything I've read online recommends to not have part filled concrete bottles. Once it's opened, it's best to mix it all. I've read some people have part B of the Dev go bad I think. When mixed and if it is the LU Kodak stuff then it had extra protection against oxidation from what I can gather.

 

[Bumba]

Get a 12v smps with a power rating of at least 150W. Your enlarger bulb will be just as happy with DC as it is with AC.
In a pinch a computer power supply may do fine.
The only issue is that there can be some filter capacitance on the output of the power supply which delays the bulb turnoff for a fraction of a second so exposure times of less than, say, 6 seconds or so may be slightly longer. Depends on the power supply used though. I don't think it'll be an issue with most units.

Thanks for the help Koraks. I'm getting very good repeatability right now and I think I was just losing my marbles at the time.

 

[koraks]

Thanks for the help Koraks. I'm getting very good repeatability right now and I think I was just losing my marbles at the time.

I was never any good at playing marbles so I've lost mine a long time ago, I'm afraid.

 

[Bumba]

I'm back with more headache. Think it actually was a voltage issue in the end.

So a few days ago I'm making good test strips then one comes out a little bit too dark (12s exposure). I drop the exposure by 1 second (now 11 second exposure) and carry on working away. Everything looking good and consistent results. Then today the strip comes out too light so it needs to go back to the original exposure of 12 seconds.

Looked so hard for voltage regulators here in the UK but I can't find anything (well found one for £100). This is crazy

 

[Bumba]

I've just had an idea. Could I use this voltage reader then only make exposures when voltage is at a correct level. I'll be at the mercy of the electricity at that time of day but I can live with that.

 

[Bumba]

Hi, does anyone know anything about this? Seen one for sale but not sure if it's a stabilizer and theres not much info online.

Thanks

 

[peoplemerge]

I emailed the company, will let you know if they reply.

 

[Bumba]

Thank you for the help peoplemerge but I think I read somewhere that the company went under some years ago. Who knows though. Thank you anyway

Also came across this one if anyone knows anything about it? These things look pretty ancient by todays standards haha. Might try call them tomorrow but that number looks too short and I'm not going to get my hopes up.

 

[peoplemerge]

Is this not "Rayco Electronics" ? I found their website saying they are a pioneer and innovator of magnetics products since 1941. Well, they didn't reply to my email, but they are answering the phone. You might try them at 1.310.329.2660.

What you can also do is simply plug in a voltmeter like the one you took a picture of. If you already have a voltmeter, make sure it's on "V~" for AC or you'll kill it. If it changes over time, you don't have a voltage regulator. Though if I had to guess, either would work well. 6A is more than you need to pull if my enlarger power math works out.

 

[Bumba]

Is this not "Rayco Electronics" ? I found their website saying they are a pioneer and innovator of magnetics products since 1941. Well, they didn't reply to my email, but they are answering the phone. You might try them at 1.310.329.2660.

What you can also do is simply plug in a voltmeter like the one you took a picture of. If you already have a voltmeter, make sure it's on "V~" for AC or you'll kill it. If it changes over time, you don't have a voltage regulator. Though if I had to guess, either would work well. 6A is more than you need to pull if my enlarger power math works out.

Oh thanks for the help peoplemerge I'll give the number a try. Good idea about plugging in the voltmeter into it too. The voltmeter should be here tomorrow so I'll see what my voltage is like first before I order one of these potential stabilizers.

How does the amp rating work? One of them is. 6A and the other is 13A max but I think UK mains sockets work at 13A. Would the 6A one be alright running off that or is that too high for it? I never paid much attention in physics lessons unfortunately

 

[RedSun]

C41 blix has a bad rep for breaking down but it should not be confused with RA4 blix, which was different properties and is much more stable than C41 blix. As I have written above, I had no problems whatsoever with long term storage of Blix replenisher and tank solution from the RT/LU kit over several years (!) in PET containers and wine bags respectively. Store the blix at normal room temperature it does not like too cold temperatures, IIRC.

I reckon reusing the chemicals would make it difficult to include a prewet and a stop bath. The prewet will dilute your developer over time. The stop bath will change the blix pH over time. OTOH, it might be not relevant as long as you permanent "tank" solution is large enough (something in the 3-5 liter range).

I have opened RA-4 blix concentrate that has formed residual all round the original bottle. It was opened 5 years ago. Do we think it is good or bad?

 

[peoplemerge]

Oh thanks for the help peoplemerge I'll give the number a try. Good idea about plugging in the voltmeter into it too. The voltmeter should be here tomorrow so I'll see what my voltage is like first before I order one of these potential stabilizers.

How does the amp rating work? One of them is. 6A and the other is 13A max but I think UK mains sockets work at 13A. Would the 6A one be alright running off that or is that too high for it? I never paid much attention in physics lessons unfortunately

Amperage in this context just describes the maximum current you can pull off the power supply. If you look on your circuit breaker box, the breaker for your plug is a 20A, at least that's household in the USA which is 110. Intuitively, 6A is really a lot of current (it's 30% of what a 10A breaker can sustain). Most timers are rated about 500W but let's see, you mentioned you have a Durst M370... googling http://www.davidutrilla.com/cajon/durst_M_370.pdf (this is a good read for you btw). Let's assume your enlarger is equipped with the 100W halogen bulb... how many 100W lights can you turn on in one room without tripping your breaker? 20? Googling https://www.thespruce.com/calculate-safe-electrical-load-capacities-1152361 "20-amp 240-volt circuit: 20 amps x 240 volts = 4,800 watts" yes that's the power formula. So 6A x 240 volts = 1440 watts. So it will work but is 3-10x overkill for your needs.

I have a collection of timers, and one of them is a "Omega E-99 Enlarging Timer" - and happened to notice it includes a voltage stabilizer. There is one right now on that auction site, shipped to you in the UK for under 60 GBP, and you'll then have a precise digital timer.

EDIT: Wait, scratch that idea, this is a US model only going to input and output 110. Don't waste your time with that. You should be able to find plenty of darkroom timers in the UK, and if you choose carefully, you can probably find one that has stabilized power.

 

[peoplemerge]

I have opened RA-4 blix concentrate that has formed residual all round the original bottle. It was opened 5 years ago. Do we think it is good or bad?

Depends somewhat on who manufactured it. If it's a single concentrate, forget it. If the bleach is separate from the fix, then it's probably the fix desulfering. Toss the fix and try mixing the bleach with an ordinary ammonium thiosulfate fix.

 

[RedSun]

Depends somewhat on who manufactured it. If it's a single concentrate, forget it. If the bleach is separate from the fix, then it's probably the fix desulfering. Toss the fix and try mixing the bleach with an ordinary ammonium thiosulfate fix.

It is the SP blix. I've opened a new bottle that looks good.

 

[Bumba]

Hi everyone, I measured my voltage last night and today and it fluctuates between 233-236v. For consistency while printing how tight should I keep it? Between 234-235 or can I get away with more?

Also if I had a voltage stabilizer, how stable would it keep my voltage. I read that some are +/- 1% so that would be 231-236 which is pretty similar to what I already get or do stabilizers keep it at one exact voltage?

Thanks

Just measured it now and it's at 232v so there's a fair range of voltage and this is definitely affecting my density and shifting the colours red. This should be in more darkroom books haha

 

[Bumba]

Just learned that a 5V change can lead to a 14% change in light intensity. This might help someone in the future. Im exposing at 11s and a 14% change is 12.5s and this is a noticeable difference in density for me. I'm regularly getting shifts of around 5V everyday and I feel like my line is fairly stable.

Just something to consider for anyone having difficulty with consistency. I bought one of those 'kill-a-watt' devices for £10 and it helps monitoring when and when not to print. It's still early days but I'm going to aim for a 1.5 voltage difference when printing to get best consistency and that seems fairly possible.

Hope this helps someone because it can be frustrating and not all enlargers have stabilization built in

 

[Bumba]

Sorry I'm back again with a question for those who are savvy with electronics. I've found a stabilizer but I think it's a 100V one. My questions are:
1) will the stabilizer draw only the 100v it requires from the mains which is 230v or will something blow up?
2) if it's outputting 100v and I plug that into my Durst transformer which says it requires 240v on it will that cause any damage or will the Durst transformer just take the 100v in and step it down to 12v for the bulb?

Thanks for any help. This is so confusing

 

[koraks]

Your 100V device will not play nice with your 230/12V setup. Smoke will ensue, potentially followed by tears.

 

[Bumba]

View attachment 240009

Your 100V device will not play nice with your 230/12V setup. Smoke will ensue, potentially followed by tears.

Haha the tears are already flowing. Which thing would cause the problem in the set up?

This is what I was looking at. It either says max load 100v or 100vA

 

[koraks]

It's not clear from the picture what the ratings are. Btw, a 100V stabiliser seems a bit odd since there's no common domestic application of 100V. So maybe it's VA in which case it's a power rating (a bit like Watt), but then the voltage is still unclear.

 

[Bumba]

It's not clear from the picture what the ratings are. Btw, a 100V stabiliser seems a bit odd since there's no common domestic application of 100V. So maybe it's VA in which case it's a power rating (a bit like Watt), but then the voltage is still unclear.

Yeah I'm not too sure either. I'll do more research if I can. Thanks anyway Koraks

 

[Bumba]

Okay the stabilizer I ended up buying was the one above. It's specs are input: 240v, output 220v, max load 6a.

My enlarger transformer requires 240v and 120va so 0.5a. It then outputs 12v at 100va.

Is the stabilizer a bit too much for my transformer or should it work? Will the circuit only draw the 0.5a the transformer requires or the 6a that's the max load?

I'm so confused. I just wanted to print some photos

One more thing I just realised. The max load of the stabilizer above was 100va and the enlarger transformer outputs 12v at 100va so I'm assuming this would also work too but only just.

 

[Bumba]

Right guys, I've come across a Durst EST305 for sale which should work for me but I need to rewire the fitting in it. Does anyone have any experience with it? I've read they're quite prone to failure and what sort of stability should I expect from it?

Thanks

Also is this a stabilizer or just a transformer? It's the Rayco one from above. The out 220v one