Good results with HP5+ (also 400TX) and DK-50 1:1

[Paul Verizzo]

I'd rather not look! LOL!

 

[Murray Kelly]

Your laughter has them crying .... all the way to the bank.

 

[Michel Hardy-Vallée]

Okay, so now that I have a densitometer, I've been measuring everything transparent and reflective around the house. Eventually I settled for something useful like films and papers.

Here's a graph, done to the best of my capabilities, with due care to scale and proportion of axes (both are in logE units), for HP5+ in DK-50 1:1 (replenished), for 4, 5:15 and 7 min. It's followed by one for HP5+ in XTOL, for comparison. Everything done with a Stouffer T2120 step wedge and a Dektronics densitometer.

Main observations:

- DK-50 turns HP5+ into a long-toe film. Comparing its effect to XTOL, the difference is dramatic. Whereas XTOL gives about a stop or so of toe before the straight line, with DK-50 you have at least half of the curve as toe and the other as straight line. Good news for those who miss 320 TXP in 120!

- This upswept curve is why people keep recommending DK-50 for portraits, because you have good highlight separations, but the shadows fall quickly. That's a classic portrait look.

- This may be a consequence of how films react today, but I noticed that extended development on both DK-50 and XTOL had comparable effects. Both of course increased base fog. With DK-50, going from 4 min to 5 min, you can see the typical progression of the curves, but at 7 min, this stops. DK-50 raises the toe, but does not increase the contrast of the straight line portion. So it means that with increased development you get muddier shadows and midtones. With XTOL, I could see an increase in contrast going from 5 min to 7 min, but after that, you only get more overall density; you don't get much increase in contrast even at 10 min.

Lessons:

1) I won't be chasing after extended development with HP5+. Should I really need it, I will either try something very responsive like T-Max or very old fashioned like FOMA.

2) Don't be scared by the "studio portrait only" recommendations around DK-50. You can use a long toe very well outside, if you know how to analyse a scene. It's up to you to find where this characteristic works for you. So far, I've liked it for photos with a lot of textures, evenly lit scenes, or when I want brilliant highlights. It absolutely doesn't work for me on nature scenes with a huge SBR where you need shadow detail.

 

[Paul Verizzo]

Way over my head, although I certainly appreciate your efforts. I lack the hardware and the patience to understand such matters.

Diluted DK-50 surely would have been pegged as an "acutance developer" fifty years ago. Versus D-76, Ansco 120, etc. "fine grain developers.

The good news is with a hybrid darkroom, and the right computer program, one can "fine grain" a high acutance image to whatever results are desired.

 

[John Wiegerink]

Way over my head, although I certainly appreciate your efforts. I lack the hardware and the patience to understand such matters.

Diluted DK-50 surely would have been pegged as an "acutance developer" fifty years ago. Versus D-76, Ansco 120, etc. "fine grain developers.

The good news is with a hybrid darkroom, and the right computer program, one can "fine grain" a high acutance image to whatever results are desired.

Yes, I read that with higher dilutions that DK-50 was very similar to FX-1 without the Potassium Iodide. I tried it, and it does seem very close, but didn't have any FX-1 to compare it to at the time. I have my times written down somewhere, but like my vision glasses, I have misplaced them somewhere. I'll see if I can hunt up the dilution ratio and starting times. If I do, I will post them.

 

[John Wiegerink]

I found it! This came from Gerald R. Koch:

Actually DK-50 makes a very good acutance developer when diluted 1+4 with enough metaborate added to raise the concentration to that of the undiluted developer, that is 10 g/l. Development times are 8 to 13 min @ 20C.

 

[removedacct3]

Main observations:

- DK-50 turns HP5+ into a long-toe film. Comparing its effect to XTOL, the difference is dramatic. Whereas XTOL gives about a stop or so of toe before the straight line, with DK-50 you have at least half of the curve as toe and the other as straight line. Good news for those who miss 320 TXP in 120!

Michel, can you elaborate on the shelf life when using DK-50 1+1 replenished? Did you notice any activity change over time?

 

[Michel Hardy-Vallée]

Michel, can you elaborate on the shelf life when using DK-50 1+1 replenished? Did you notice any activity change over time?

It's pretty stable. I've mixed it a couple of months ago, and it hasn't changed. I replenish it every time I use it (30 ml/roll), and it's been consistent. DK-50 is already a pretty stable developer.

 

[removedacct3]

It's pretty stable. I've mixed it a couple of months ago, and it hasn't changed. I replenish it every time I use it (30 ml/roll), and it's been consistent. DK-50 is already a pretty stable developer.

Thanks that is good to hear. I was about to give it a go when I found out that I was out of Metol. Next week I will get my hands on it and immediately will mix a batch. Looking forward to see the results of HP5+ at 320 in the studio with strobes.

 

[Michel Hardy-Vallée]

Thanks that is good to hear. I was about to give it a go when I found out that I was out of Metol. Next week I will get my hands on it and immediately will mix a batch. Looking forward to see the results of HP5+ at 320 in the studio with strobes.

I haven't yet done the proper speed testing, but empirically I used EI 250, so you may want to play around with exposure index before committing.

 

[removedacct3]

I haven't yet done the proper speed testing, but empirically I used EI 250, so you may want to play around with exposure index before committing.

I too will do a proper test and I am very curious to see the outcome. But before I do, I will let the developer ripe. My plan is to mix about 1200 ml (that is a storage bottle of glass filled to the brim) of DK-50 1+1, developer about 5 films, start replenishing using 1+1 replenisher, do another couple of rolls. When all that is done, I assume that the developer is well seasoned, stable and a proper test can be done.

 

[John Wiegerink]

It's pretty stable. I've mixed it a couple of months ago, and it hasn't changed. I replenish it every time I use it (30 ml/roll), and it's been consistent. DK-50 is already a pretty stable developer.

Michel,
I'm curious about your method of replenishment for DK-50 1+1. I use Xtol-R and my setup Is a brown Boston gallon jug for the working solution and a wine bag bladder contains my replenisher. When I develop a roll of 120 I measure out 80ml of replenisher from the wine bag and pour it into the working jug while developing the roll. Then when developement time is over I pour the used developer back into the gallon working jug to top it off and seal it back up.
If I understand what you are saying is that you pour your used developer back in the working jug and then add your 30ml of replenisher. Did I get that right? I don't think I would have enough room for 80ml of Xtol replenisher in the working jug if I did it that way.

 

[ags2mikon]

I do mine just like Michel does. Most of the time I have to dump a few cc's down the drain.

 

[grain elevator]

1) I won't be chasing after extended development with HP5+. Should I really need it, I will either try something very responsive like T-Max or very old fashioned like FOMA.

Anyone got an explanation for what's happening here? I though people successfully push/expansion develop HP5+, what does this not seem to work in your tests?

 

[John Wiegerink]

I do mine just like Michel does. Most of the time I have to dump a few cc's down the drain.

OK! I will continue with the way I do it. Yes, after I add the 80ml of replenisher to the gallon working jug I usually can't return all the developer from the developing tank and the excess goes down the drain.

 

[Michel Hardy-Vallée]

I too will do a proper test and I am very curious to see the outcome. But before I do, I will let the developer ripe. My plan is to mix about 1200 ml (that is a storage bottle of glass filled to the brim) of DK-50 1+1, developer about 5 films, start replenishing using 1+1 replenisher, do another couple of rolls. When all that is done, I assume that the developer is well seasoned, stable and a proper test can be done.

Yes, I ripened my batch too before I started using it. I just took a couple of lengths of 35mm HP5+ from a bulk roll and processed it with the lights on.

 

[Michel Hardy-Vallée]

Michel,
I'm curious about your method of replenishment for DK-50 1+1. I use Xtol-R and my setup Is a brown Boston gallon jug for the working solution and a wine bag bladder contains my replenisher. When I develop a roll of 120 I measure out 80ml of replenisher from the wine bag and pour it into the working jug while developing the roll. Then when developement time is over I pour the used developer back into the gallon working jug to top it off and seal it back up.
If I understand what you are saying is that you pour your used developer back in the working jug and then add your 30ml of replenisher. Did I get that right? I don't think I would have enough room for 80ml of Xtol replenisher in the working jug if I did it that way.

I'm following pretty typical recommandations from Kodak and around.

I have a 2L jug that contains my DK-50 1:1. I measure out whatever I need (so let's say about 500 mL for a roll of 120), process, then dump it back in the jug. After that, I add 30 mL of DK-50R 1:1 (the replenisher), shake it a bit, and put it back on the shelf. Occasionally I dump a few mL if I'm tight in the bottle. I also sometimes filter the developer through a 1 micron filter bag to remove the dust/crap/particles that may or may not get into the developer.

I made a note to dump 2/3 of my jug after it has processed 30 rolls, and replace it with fresh DK-50. That way, the reused 1/3 is my "starter" for the next batch. It's like sourdough.

 

[Michel Hardy-Vallée]

Anyone got an explanation for what's happening here? I though people successfully push/expansion develop HP5+, what does this not seem to work in your tests?

Not fully sure, but already in 1981 Ansel Adams was remarking "contemporary thin-emulsion films have less capacity for increasing their maximum density than earlier materials." (The Negative, p. 83). Adams does not cite sources.

The other option I could see is gamma infinity, defined by Haist as "Gamma will be found to increase rapidly at the shorter times of development, but the increase in gamma is much less per increment of time at the longer times of development. Eventually, a maximum value of gamma, called gamma infinity (y∞), is reached.

Have I reached Gamma Infinity? And beyond? Or maybe, I needed to jack development time higher to 10-15 minutes to see anything significant.

 

[ags2mikon]

It has been a while since I read Kodak's instructions about DK-50 but I don't remember them advising the use of "ripening" the developer. I think it was mix it and begin using it with replenisher 30cc per 80 sq in of film. I think a lot of folklore gets mixed with the chemicals. The practice of "ripening" could add more bromides to the mix and act as an inhibitor. One of my future projects is to mix a new batch and run a test to check densities and then later 10 rolls or so with replenishment then do it again to see what changed. I worked at a weekly paper in the early 70's and we used both dk-50 and dk-60 and did not "ripen" the chemistry. The owner would fire you on the spot for not following Kodak's instructions. We used the DK-60 for 35mm and DK-50 for everything else.

 

[John Wiegerink]

I ripen my Xtol for replenishment, but when I used DK-50 for a short spell I never ripened it. Just mixed and used. Of course, I wasn't using DK-50 replenished either, which might make a bigger difference.

 

[Michel Hardy-Vallée]

A few more tests today. I did a series of exposure in-camera at EI 400 with DK-50 1:1 and XTOL stock, and I now understand why I use a lower EI for DK-50, even though both developers give the same effective speed. The upswept shape of the DK-50 curve gives a different tonal rendition in the midtones than that of XTOL.

However, the same exposure gives me 0,1 above B+F, namely two stops below nominal exposure (so a Zone III gives me 0,1 for either).

That means I have to take into consideration the shape of the curve when I meter for DK-50. With XTOL, it's pretty linear, so even if I under- or overexpose a little, tonal separation remains consistent. With DK-50 I have to decide what goes where. That's why the photos I made so far that worked best where those I analyzed carefully with a spot meter. Exposing for the highlight can be an expedient way to ensure they don't blow out.

 

[Craig]

If you look at the film testing here, ( https://fotoimport.no/filmHP5) you'll see that HP5 is practically a "perfect" film in either Xtol or D76. In Xtol especially, it's true to speed and has a very long straight portion. No other 400 speed film he tested has the same long, straight curve. FP4 is very similar curve shape to HP5, and also true to speed.

Notice how Tri-X in D76 doesn't make box speed ( while HP5 does) and there is quite a pronounced shoulder. TMax 400 in Xtol has virtually no straight line, it's a big S curve.

The upper portion of each chart is a small crop from a test scene he photographed.

 

[gorbas]

I'm thinking about using diluted DK-50, one shot.
Did anybody come with dilution chart for DK-50, for how much to extend developing time from straight to 1:1, 2, 3, 4, 5....?
For my taste, even 1:1 around 5-6 min is too short, I'm looking for developing times around 10 minutes, something like 1:4 or more.
Will 60ml of stock DK-50 in 1:4 properly and fully develop one 135/36 roll?
Thank you in advance!

 

[Michel Hardy-Vallée]

I'm thinking about using diluted DK-50, one shot.
Did anybody come with dilution chart for DK-50, for how much to extend developing time from straight to 1:1, 2, 3, 4, 5....?
For my taste, even 1:1 around 5-6 min is too short, I'm looking for developing times around 10 minutes, something like 1:4 or more.
Will 60ml of stock DK-50 in 1:4 properly and fully develop one 135/36 roll?
Thank you in advance!

In Anchell & Troop (pp. 83-84), they mention that Geoffrey Crawley published in the British Journal of Photography a two-part DK-50 formula meant for dilution, and one-shot usage.

BJP Dilute DK-50 (stock)

Solution A

Metol 2.5g
Hydroquinone 2.5g
Sodium Sulfite 30g
Potassium Bromide 0.5g
Water to make 1 L

Solution B
Sodium metaborate 50g
Water to make 1L

The working solution is 1 part solution A, 1 part solution B, 3 parts water (1+1+3)—so that in effect you're diluting the original DK-50 at 1+4. Anchell & Troop recommend for modern/tabular films to dilute the BJP formula 1+1+6, and for higher sharpness to dilute 1+2+8. For better midtones, they recommend 2+1+7.

 

[Murray Kelly]

With T-grain 400 @ box speed I use DK50 1+9 for 14 min at 20C. The results are excellent. I found times to be remarkably like FX55 times for some unknown reason.

I should add that subbing the metol with Phenidone 0.25g will get you FX37

Good luck
Murray