D-23 1:1 SemiStand

thronobulax said:
Both Borax and Sodium Hydroxide (lye) can be used as Kodalk equivalents :
Click to expand...

I hope you have not misunderstood the photrio post you linked. What the post says is that
the following two solutions are equivalent:

1.
Borax: 7 g
Lye: 1.5 g
Water to make: 1 l

2.
Kodalk: 10 g
Water to make: 1 l

Neither Borax nor Lye in itself can be a substitute for Kodalk in any of the developer formula discussed in this thread. You need to use both and in the recommended amounts.
 
I find it confusing too. It’s rather like the “black side out = exposed” convention, where some people are deviants, for what must seem like sensible reasons to themselves.
I’m off to look at some Kodak packaging, just to see what the former giant of photography uses.
 
I don’t seem to have much Kodak stuff, so I looked up the instructions for HC-110.


As you’ll see, they give actual quantities of water and the stock solution to make up different final volumes of each dilution. The final column is headed “Ratio of stock solution to water.” Note - not to final quantity, which would be different. 1:3 solution:water would be 1:4 solution to final quantity.
Clearly this leaves plenty of scope for the unwary mind to be confused.

My bottle of Selenium Toner is very loosely expressed. “Dilute 1 part toner with 3-19 parts water.” More-or-less equivalent to “bung some in.”

I’ve discovered a pack of Hypo-clearing agent. The pack says it’s to make 25 litres and goes on to suggest making up five litres and diluting as required at 1+4.

Although Kodak seem to be correct in all their usages, they are far from being consistent.
 
Well now,
I've read more of the HC-110 leaflet and although it's packed with information, it does seem to be a source of confusion. Whoever wrote it seems to be struggling to reconcile the clear presentation of metric units and the higgley-piggldey units forced on an infant USA by the Tyrant George III.
They do head their tables as ratio of stock-to-water and concentrate-to-water. Under this heading, 1:1 does correctly mean one unit of agent and one of water. In the usual system, of concentrate-to-final volume it's meaningless - it means one-oneth. That it, one. The final volume equals the final volume. True. but on the far side of unhelpful.
Putting aside the idea that poor teaching of maths is not blame, could this eccentricity of Kodak's be to blame for the confusion?
It does seem to be an odd thing to quote. It's not as though water were a precious commodity. Surely we are interested in the active ingredient's volume, because that has a direct influence on the developer's activity, and the final volume, because that is determined by the size of the tank or tray.
 
Raghu Kuvempunagar said:
I hope you have not misunderstood the photrio post you linked. What the post says is that
the following two solutions are equivalent:

1.
Borax: 7 g
Lye: 1.5 g
Water to make: 1 l

2.
Kodalk: 10 g
Water to make: 1 l

Neither Borax nor Lye in itself can be a substitute for Kodalk in any of the developer formula discussed in this thread. You need to use both and in the recommended amounts.
Click to expand...

Yes, noted, thanks for pointing that out.

I did do a semistand development of APX 100 in DK-50 1:5 with 0.5g/l of NaOH added. It produced very sharp, splendid negatives.

Some of the scenes were a guess at exposure because it was in a forest glade in the later afternoon with limited light. So, I shot at 30, 40, 50, and 60 seconds. Interestingly, there is not a wild difference in negative density across those exposures. 30 seconds looks about right, but 60 seconds is only somewhat more dense. Whether this is attributable to nonlinear reciprocity behavior or the developer exhausting due to high dilution and standing, I don't know, but it was interesting to observe.
 
Or perhaps to the evening drawing in as you made the successive exposures?
 
David M said:
Well now,
I've read more of the HC-110 leaflet and although it's packed with information, it does seem to be a source of confusion. Whoever wrote it seems to be struggling to reconcile the clear presentation of metric units and the higgley-piggldey units forced on an infant USA by the Tyrant George III.
They do head their tables as ratio of stock-to-water and concentrate-to-water. Under this heading, 1:1 does correctly mean one unit of agent and one of water. In the usual system, of concentrate-to-final volume it's meaningless - it means one-oneth. That it, one. The final volume equals the final volume. True. but on the far side of unhelpful.
Putting aside the idea that poor teaching of maths is not blame, could this eccentricity of Kodak's be to blame for the confusion?
It does seem to be an odd thing to quote. It's not as though water were a precious commodity. Surely we are interested in the active ingredient's volume, because that has a direct influence on the developer's activity, and the final volume, because that is determined by the size of the tank or tray.
Click to expand...

Back in prehistoric times, when dinosaurs roamed the earth, Mrs. Draper was trying to pound basic algebraic ideas into my unformed mind. She taught the notation of "X:Y" to always be understood as a ratio. That is, for every X quantity things, there will/must be Y quantity of the other thing. (This is explained ad nauseum in the Wikipedia citation I provided above.)

In short, I have always thus read "X:Y to mean "X parts TO Y parts" (thereby producing a total of X+Y). I have never read this as "X parts IN Y total parts".

I believe this is consistently practiced across all the photographic vendors whose specifications I have read. When they want to express the former, they use "X:Y" or "X+Y". When they want the latter, they're normally explicit about it: Pour out 2oz of gin. Add tonic to make a final volume of 10oz. Stir. Consume. Repeat as needed.

P.S. I've long ago forgiven you your tyrants. First of all, I was born in a Commonwealth country and still carry citizenship there and thus am required to be kindly to my UK cousins. Secondly, you make the best bitter in the world...
 
David M said:
Or perhaps to the evening drawing in as you made the successive exposures?
Click to expand...

I don't think so. The meter readings didn't vary much and I shot pretty quickly - all in under 5 minutes with very little change of light.
 
Raghu Kuvempunagar said:
Nice to hear this. Please do share the results when you are ready.
Click to expand...

Here you go. Be forewarned that this is a scan of a 6x9 negative done in true Rube-Goldberg style: I placed the neg on a flatbed scanner and then laid an iPad running a light table application on top of it. Other than minor curve tweaks, there is no other post processing - no sharpening or what have you. I suspect the print will look far nicer.

Agfa APX 100, ASA 100, DK-50 1:5 + 0.5g/l NaOH, Semistand for 60 mins. Shot with a Fuji GW690II, 60 seconds f/22.

1686162795824.png

It clear (to my eye, anyway) that this developer combo works great for sharpness, but doesn't have anywhere near the compensation effect of either D-23 or Pyrocat-HD.
 
I wouldn’t dare quarrel with Mrs Draper, but I suspect that some people do in fact confuse the possible interpretations of the “:” sign. Using the “+” seems unambiguous. Hence this conversation.
I didn’t know about a light-box app. Could you pass it on, please?
 
Yes, a reminder that people read the same things differently and starting with "What is your understanding of X" is a useful way to engage with others.

While I have an embarrassment of analogue riches at my disposal, I've never invested the money in a decent film scanner. I have one, but the output varies between terrible and execrable . I've tried using a DSLR to scan negatives but that's far too fiddly for my tastes.

As it happens, I have another office scanner that works very nicely and that's how I hit upon the idea of laying the negative on the scan surface and backlighting it with an iPad. The only drawback is that this scanner is limited to 1200 DPI which doesn't do these negatives justice. My next foray will be to take the same approach, but use the "film" scanner as a simple flatbed - It supposedly can resolve 4800 dpi.

App I use is here:

apps.apple.com

‎MyLight – Flashlight & LED

‎The simplest way to light up your environment! With MyLight you get everything you need for lighting. Why should you use MyLight? • Clean and simple modern interface • Supports iPhone, iPod touch & iPad • Uses the bright screen or built in LED for lightning • Different light modes for multiple...
apps.apple.com apps.apple.com
 
Raghu Kuvempunagar said:
I always thought 1:10 stood for 1+9. But the formula I gave earlier is what I used and should work fine as is.
Click to expand...

It does, but some companies use it incorrectly, Kodak for instance. In scientific applications, also pharmaceutical 1:10, is the dilution ratio.

Ilford use the + symbol to avoid confusion.

Ian
 
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