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Making my own HCA

RobertV said:
Well I even did use Agfa in the past and Foma for the last 10 years and even with Foma papers it will work.
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I've found Foma papers scratch very easily, whereas I've never had a scratch with Agfa papers at all.

So while carbonate will work it'll increase the risk of scratching so Sulphite is preferable with Foma.

Ian
 
Hey, why use it at all when a good wash will do the trick.

If the final print or film tests negative for hypo and silver retention, you have done your job.

PE
 
In the Netherlands, I would hardly call salt water or fresh water to be scarce!
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No it is normally not, but I can not find it social to run continuously water to waste just to justify a few prints or films. And by the end we also have to pay for each cubic meter.
 
Photo Engineer said:
In the Netherlands, I would hardly call salt water or fresh water to be scarce!

PE
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Well like the UK and other parts of Europe they've had water rationing during long spells of hot dry weather.

Ilford published their archival film washing technique as a direct result of water shortages and also they revised their print washing suggestions at the same time.

There's a less cavalier attitude towards resources in Europe than the US.

Ian
 
Ian;

This shortage is precisely the point of Ilford's original and marginal recommendations for washing. Using them, you often need to use a wash aid. It depends on water supply. And before you comment, yes, I am aware of how variable results can be depending on water supply! And yes, Ilford is your guiding light, but just like me, they are not perfect, and yes, Mason has essentially retracted the method original espoused by Ilford.

So, we have about 30 posts settled in one.

Oh, and yes, the Netherlands have more water than England AFAIK. England is not perfect. Another set of posts.

PE
 
Absolutely nothing wrong with being frugal!

But assuming an 11x14 tray holds approximately 2 gallons of water (or 7.5 liters) you won't be using a whole lot of water if you're careful.

Am I right in remembering that a running water wash for photos is supposed to provide one complete change every 5 minutes?
And, you're supposed to rinse a print for 30 minutes. Right? So that would be 6 complete changes of water or 12 gallons (45 liters) of water. That's 0.4 gallons (1.5 liters) per minute. Not a whole lot.

Now, is it possible that you could run your water even a little bit slower than that? What if you ran your water at 1 liter per minute and rinsed for 40 minutes? You'd only use 40 liters. How far can you push this before you get down to the point where the print is not completely washed?

Now, yes, I know... This is where the frugal part comes in.
Using a hypo clearing agent or a wash agent can cut your wash time in half. Only 20 liters would be used.
Good move!

This is just to add a sense of scale to the whole thing. The original post was talking about the need to push out a batch of prints before next Monday without having ready access to hypo clearing agent.

So, what's the opportunity cost of using an extra 20 liters of water versus missing a (self-imposed) deadline?

If it's not an everyday occurrence, I'd vote for using the extra water.
 
Guys;

Ever think of the demand on the effluent treatment by use of HCA? It is not an inconsiderable demand. Water is water, but chemicals are something else again!

This is often forgotten, but it is a "hidden" cost to the use of any extra steps.

PE
 
Okay... So I'll hold my breath while I type this so my exhaled carbon dioxide doesn't contribute greenhouse gasses to the environment...

What is the cost of processing the effluent chemicals versus just using the water?
 
Worker 11811 said:
Okay... So I'll hold my breath while I type this so my exhaled carbon dioxide doesn't contribute greenhouse gasses to the environment...

What is the cost of processing the effluent chemicals versus just using the water?
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Not measurable, the normal effluent from any house on a daily basis far out weighs the possible discharges from a hobbyist's darkroom. and is usually far more toxic

Ian
 
And I respectfully disagree.

One of the wash aids is Sodium Sulfite and another is Hydrogen Peroxide. Both place demands on the sewage system over and above the normal process as you have 2 wash steps and a chemical treatment step. This adds to BOD, COD and outright pollution. You can do the calculations yourself! Try it, and you may be surprised.

I suggest that Ian do this before he responds. I have done it at EK. The value is not inconsequential.

PE
 
Photo Engineer said:
And I respectfully disagree

I suggest that Ian do this before he responds. I have done it at EK. The value is not inconsequential.

PE
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Ron, I hate to inform you that this is one area I have rather a lot of hands on experience in, both at a practical level and more importantly also dealing directly with UK Water boards. We held licenses to dispose of rather large quantities of treated photochemistry to the sewers.

I dealt with the same chemists as Kodak Harrow (for Kodak's effluent disposal) for London based customers and was fully conversant with the in's & out's of photo chemical disposal.

Unlike you much earlier in my working life I was seconded to an effluent treatment plant to learn first hand how chemical discharges impacted water treatment works in a medium sized town with rather high industrial usage of water.

So when I say there's worse in an average house's normal daily effluent than a hobbyists darkroom effluent I KNOW EXACTLY WHAT I'M TALKING ABOUT

So stop your patronising posts.

Ian
 
Ian;

Tote up the total effluent in M/L of chemistry with and without a wash aid including the two washes and then repost your comments! I have done the molar calculations and been involved in BOD and COD calculations to produce the Kodak equivalent of this process. Consider:

Develop, stop, fix, rinse, HCA, wash and Develop, stop, fix, wash. Then add onto that dumping 1L of Developer, Stop, Fix vs the Developer, Stop, Fix, and HCA and you will see the MOLAR change in effluent. This is based not just on wash water but on the dumping of the HCA into some system somewhere someway. You just cannot ignore that!

I'm a chemist. I know what I am talking about!

PE
 
Photo Engineer said:
I'm a chemist. I know what I am talking about!

PE
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Really ?

There's more developing agent in the Urine that hit's an effluent treatment plant, than photographers dispose of, think of all the Pyrocatechin then there's the Thiourea and Sulphides. These are natural bodily discharges

I'm not saying BOD & COD aren't important, they were when Kodak killed most of the fish in a section the river Thames after an accidental discharge. However there's a reality level where dilution is so high that no hobbyists darkroom could ever have any impact on a sewage treatment works.

So please cut the bull shit.

Ian
 
Ok Ian, follow this.

Process #1, Dev, Stop, Fix, wash (8L wash) Process #2, Dev, Stop, Fix, wash, HCA, (4L wash). In process #2, the total effluent is 2x more concentrated due to the decrease in wash water. It saves water but increases BOD/COD by 2x and increases other pollutants by the same amount. And, at say 5 g/L HQ in a developer, I would hate to say my urine contains that much. I'm a dead man. Even diluted with 8L of water, that is quite a bit of HQ!

Now in process 2 we must also add in the HCA and this increases total salts by the molar amount of sulfite present.

This is not to say that the amount of water used is not reduced. I am pointing out to you that by doing so, you increase the burden on sewage treatment and actually increase the load of chemistry used.

In addition, depending on how you dispose of your chemistry, the disposal process must take into account the HCA and the Hypo and Silver salts in the HCA.

Did you ever calculate the amount of HQ in discarded developer, the amount of salts in a process +/- HCA and etc? If you did, you would understand what I am saying. This, IMHO, is not patronization, it is pointing out simple facts.

BTW, think about the normal levels of HQ, Pyrocatchin, Sulfides, or Thiourea in Urine vs that in a developer or toner. You are comparing micrograms in one case vs grams or milligrams in the effluent in another.

PE
 

I've done all that for large scale processing, the worst case scenarios etc, maximum levels.

The truth is even large volumes of photochemistry have vurtually zero impact on sewage treatment plants provided the discharge isn't a sudden large accidental undiluted accident.

When I worked at a sewage treatment works (1972) there was far more commercial processing, and no issues, there was also less silver recovery taking place.

Some sewage treatment plants actually saved money when they were treating colour labs effluent as they needed to add EDTA to treat the water otherwise

I sat on your side Ron, we had to keep our company and customers fully bcompliant, and doing the best all round. Our customers had so many mixed responses from local officers that I went direct to the top Chemists in each Authority, and after that any discharge application was reffered to them.

Maybe I have a broader overview of all aspects of life than you. 100,00 people urinating a few times daily is far more Pyrocatechin than all the film photographers developing agents being discharged over the same time scale.

But then that doesn't take into account the huge amounts of PPD that are sold daily to mostly women but also some men in hair dyes..

Now lets have a REALITY CHECK. A few bottle of dev etc get sold in a town, that's nothing compared to all the hair dyes with PPD, probably far less than 1%.

So compare the number of women & men who use hair dyes to the number of photographers using film and it puts things in a very different perspective.

Ian
 
Yes, all well and good and all quite true Ian for the billions of people on this earth, but we are talking about one person doing film and printing in their darkroom.

So, does this person save anything by using HCA? This is what I am trying to address and which is being obfuscated by your "arguments". On the world-wide scale you are describing or even at a one person scale, no, a person is not materially saving by using HCA. The effluent is more concentrated and the chemical load per session is greater. But, they use less water. On balance, they generally lose out.

That is the key issue here! Not the distracting elements however true for the whole world or for the whole municipality! After all, as you point out, one person doing analog photos is a drop in the bucket. This is true of their water consumption and so why use an HCA to save a few liters of water? In most places that is just not significant! In fact, they can use up to 1/4 or 1/2 of the water saved just by mixing up the HCA itself.

PE
 
Sewage is a highly reducing environment regardless of photographic processing. Photographic chemicals - sulfite, developing agents, etc. - certainly add to the oxygen demands in resolving sewage effluent. But the number of amateur darkrooms and the volume of their processing is insignificant compared to the volume of reducing agents from other source. The same may not apply for large commercial laboratories, which could add significantly to the load, especially in a local area.
 
So, where do you think it balances out?

If I'm doing a couple-few prints at a time it's probably better to just rinse for 20-30 minutes and be done with it. But, if I'm going to be printing and washing all weekend long, would it be better to use HCA or still just rinse them?

I live in the Great Lakes watershed. There's no problem with water here. We pay about $2.25 per 100 cu. ft. (I think that comes out to about 0.08 cents per liter.) That would be around 3¢ to wash a print for 20 minutes. I usually wash a couple-three at a time. (Shuffling them in the tray every few minutes.) Basically, it's a penny a print to rinse in plain water.

Spare the math... It costs me about 29¢ for a batch of HCA to wash the prints in but it only saves me 1.5¢ worth of water. So I am at a 27.5¢ deficit when I use HCA versus just washing. (I added in the cost of the water, too.)

What's the opportunity cost of using HCA versus washing alone?
If I'm saving 25¢ worth of damage to the environment by using HCA it's a no-brainer. I'll do it every time. But, WTF am I doing spending the money if it comes out to be less than a break-even situation, environmentally speaking.

To be honest, I do it both ways. If I'm just doing a couple prints I'll rinse. If I'm doing a weekend long session, I'll mix up some HCA. If I'm using fiber based, I'm more likely to use HCA unless I'm only doing one print. If I'm using RC paper, I'm more likely to just rinse unless I'm doing a whole bunch of them. And, if I'm making a really important print that I want to be sure will last a long time I'll use hypo clearing agent AND I'll rinse a long time just to be doubly sure I got the print clean.

For me, knowing where the tipping point is would help determine when to use HCA, if at all.

A fresh batch of Kodak Hypo Clearing Agent only costs me about $5.00 + sales tax but, what the hell, that's another $5.30 I can spend on film, instead!
 
Well, that was my point guys. You are close to the break even point in most places. If you have good sewage and water then you are probably losing and if you are in a very dry environment you may (may) be gaining. I am trying to heighten awareness of this. HCA is not always a good thing! Just think about it and reason it out.

Thanks.

PE
 
never take your water supply for granted. We never had a water supply problem while I was growing up - washing a print for 45-60 minues was the norm. With HCA I could cut that down to 15 minutes..

Then we had a little drought - our water reservoirs went from 90% full to 19%, and we went onto severe water restrictions...

I used to use HCA because it was good for archival processing - now I use it to conserve water...
 
And, I have never used it! We did not use it at EK, nor did any of the pros use it. We did not use it at the Cape either.

PE
 
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