My PC-512 Borax Developer

[albada]

@Alan Johnson What is the Base+fog like on these metaborate variants? One of the things that is much better with PC-512 Borax vs PC-Glycol is that it has basically no worse fog than most commercial developers. I had attributed that in part to the pH difference.

When I was creating the Mocon developer, I observed that some films had higher fog when the developer used phenidone (instead of dimezone s) and was dissolved in propylene glycol (PG). Here's the article about it. Based on that experience, I suspect the additional fog is caused by the combination of phenidone and PG.

Mark

 

[Radost]

Hey everyone, I went mostly silent here for a year... life caught up. But early last year while working on two bath developers I ended up with a formula that I liked a lot for a single bath developer. It's not revolutionary at all, but I have been using it a lot and really like the results. You might, too, so I wrote up a post about it on my blog:

A Simple Phenidone/Vitamin C Concentrate Developer: PC-512 Borax

What follows is how I formulated a very nice developer that I have now used pretty much exclusively for the last year and a half. As it says in the title, I have called it “PC-512 Borax”. Creative name? No. But it is indicative of the formula. This nice developer is a secondary result of some...

imager.ie

It's a developer in the family of PC-Glycol. I have used that developer a lot and this one gives me substantially better results. It also has a much better Dmin than PC-Glycol, about 0.3 for Delta 100.

Here are some photos I developed with it (Delta 100)


View attachment 321968 View attachment 321967

This looks a lot like the clarity of xtol. Very precise realistic representation of highlists mids and shadows.
I really like it.

 

[Alan Johnson]

@Alan Johnson What is the Base+fog like on these metaborate variants? One of the things that is much better with PC-512 Borax vs PC-Glycol is that it has basically no worse fog than most commercial developers. I had attributed that in part to the pH difference.

Attached a pic on a light box of Delta 400 developed in HC-110, DCM18 and replenished Xtol. I don't see a problem with base +fog using Metaborate in Glycol, at least with Dimezone-s.

 

[JWMster]

The gold standard...

Alan: RE: Post # 326 photos in this thread

In many ways, these shots ARE a gold standard. Thank you. And if I may ask, whether you hand agitate your developer or use a Jobo or similar? I'm beginning to think some of my grain issues might ameliorate with a bit softer agitation (which I hope to test later today). Just curious. Thanks!

 

[Alan Johnson]

My development process is not unusual, small tank, 5 inversions at start then 2 inversions at the top of each minute.
Maybe grain issues might be worth a new thread, IMO printing with an enlarger gives finer grain than any method of scanning.

 

[Donald Qualls]

PCM20 [and probably HC-110] do not work with microfilm type films to give pictorial contrast,

Dilute more. I've used HC-110 at 1+127 on Imagelink and Fuji microfilms at EI 25 with good results.

 

[Alan Johnson]

Dilute more. I've used HC-110 at 1+127 on Imagelink and Fuji microfilms at EI 25 with good results.

Thanks Donald, I will have another try with Spur Ultra-R 800 or Adox CMS20 later.

 

[Donald Qualls]

I will have another try

One thing that helps film speed in my experience with high dilutions (I've also used Parodinal at 1+100 on microfilm stocks) is to reduce agitation. My usual process for high dilution developers is use a time as if pushing +2 (i.e. add 40% to published "normal" times, if available) but cut agitation to every third minute. This will pick up 2/3 to 1 stop of shadow speed with most films I've done it on, while keeping contrast apparently normal (i.e. no "chalk and charcoal" look as of pushed film). Grain? On microfilm stocks? Not really a concern unless you're shooting Minox...

 

[Alan Johnson]

Alan, thank you for performing this experiment! I wanted to try modifying my Mocon developer like this, but eventually forgot about it. PCM20 is roughly the same formula as Mocon, but with no sulfite and about 1/4 as much ascorbic acid.

Mocon concentrate showed no deterioration (yellowing, or crystallisation, or separation) after years when kept frozen. At room temperature, it began yellowing after about six months.

However, in my article on Mocon, I mention that a major factor in crystallisation or separation is the ratio of metaborate to ascorbic acid. I found that a solution is stable for a ratio up to around 0.4 or 0.5. Above that, the concentrate collapsed after a week or two at room temperature. The ratio of PCM20 is 20/12 = 1.67, which is far above 0.5. On the plus side, the overall concentration is lower, so perhaps it will be stable. I suggest watching the room-temperature concentrate for a few weeks. Any crystals or smoke-like white wisps indicate failure. Even if it fails at room temperature, it might last a long time if kept frozen, so I suggest also keeping a bottle in the freezer.

Mark

It is rather disappointing to find that after 12 weeks crystals have appeared in the PCM10 storage sample and a lesser amount in the PCM20 (pic). These may be metaborate as the ratio 1.67 is greater than 0.4-0.5.
The sample of PCM20 I am using is only 4 weeks old and has no crystals, I will carry on unless there seems a better idea.

 

[albada]

It is rather disappointing to find that after 12 weeks crystals have appeared in the PCM10 storage sample and a lesser amount in the PCM20 (pic). These may be metaborate as the ratio 1.67 is greater than 0.4-0.5.
The sample of PCM20 I am using is only 4 weeks old and has no crystals, I will carry on unless there seems a better idea.

Alan, were these clear when you mixed them? I'm surprised at how yellow they've become after only 12 weeks. And yes, the growth of crystals is disappointing. If the crystals can be made to dissolve under heat (I suggest a water bath), then they are not due to the separation I encountered with Mocon. Perhaps a PCM5 would not crystallise.

 

[john_s]

It is rather disappointing to find that after 12 weeks crystals have appeared in the PCM10 storage sample and a lesser amount in the PCM20 (pic). These may be metaborate as the ratio 1.67 is greater than 0.4-0.5.
The sample of PCM20 I am using is only 4 weeks old and has no crystals, I will carry on unless there seems a better idea.

Did it become colder around the time?

What bothers me is that I would have expected, if the crystals have just come out of solution, that the lower concentration version PCM10 would exhibit it less or not at all compared to the more concentrated one.

About the yellowing: About the effervescence around 55degC, it seems that it's water of crystallization being expelled (see my post #350 link to data from borax.com) but since water mixes with PG, it's still there in solution. Would it be feasible to remove at least some of the water by heating the PG + metaborate to a higher temperature? I would be inclined to do it before adding the two developing agents (once it had cooled.)

 

[Alan Johnson]

The two shown in the pic, post 409 are kept to see what happens if the developer concentrate is just left in store so I will leave them to see if/how the crystals grow. They were clear when made up. Maybe eventually they could be re-heated to see if the crystals re-dissolve.

For a few days before the crystals were noticed the temperature dropped by about 15F to 55F.It is surprising that the PCM10 is most affected. My conclusion so far is that the occurrence of these crystals means that this glycol mix is likely to be of interest only to a few hobbyists who have a quantity of metaborate, most people would be better off mixing @relistan's formula for 512 Borax.
For actual use I have a separate mix of PCM20, not the storage samples illustrated. After 4 weeks this is still clear.

 

[relistan]

Attached a pic on a light box of Delta 400 developed in HC-110, DCM18 and replenished Xtol. I don't see a problem with base +fog using Metaborate in Glycol, at least with Dimezone-s.

Yep, those look perfectly fine to me in comparison to the XTOL.

 

[relistan]

This looks a lot like the clarity of xtol. Very precise realistic representation of highlists mids and shadows.
I really like it.

Thanks! I have made this my main developer now for almost everything.

 

[relistan]

It is rather disappointing to find that after 12 weeks crystals have appeared in the PCM10 storage sample and a lesser amount in the PCM20 (pic). These may be metaborate as the ratio 1.67 is greater than 0.4-0.5.
The sample of PCM20 I am using is only 4 weeks old and has no crystals, I will carry on unless there seems a better idea.

At least at the pH of the mixture without the metaborate, I think my formula has the ascorbic acid near saturation. I say that only because it's about the most I've ever been able to get to dissolve at the temperatures I'm willing to work at. I wonder if the higher pH of the concentrate is better or worse for that? It's surprising that the PCM10 is worse than the PCM20, though, I agree. Unless the higher pH is actually the reason it is better in the PCM20.

 

[Alan Johnson]

Attachment shows the crystals at 17 weeks, little changed from 12 weeks.

To see if it is possible to re-dissolve the crystals, I used a sample of PCM18 with crystals in a glass bottle.
The bottle without cap was placed in boiled water and the contents stirred every few minutes, the water being brought to the boil every few minutes. The temperature of the PCM18 sample was found to be 65-75C. This was continued for 1hour and the bottle removed and cooled.

Next day this sample was found to be cloudy and orange [oxidation of ascorbate].It was tested for activity by comparing with a colorless sample of DCM18 [all I had]. There was very little visible difference [the test is not that accurate] in negatives from the same strip of film developed for the same time& temperature at the same dilution using the heat treated orange PCM18 sample and the DCM18 sample.
This suggests that if it ever becomes necessary to re-dissolve crystals, the heating procedure described above will work.

 

[relistan]

Thanks for the update, @Alan Johnson . So the crystals redissolved and the developer, despite deep orange coloration, retains its activity. This would perhaps indicate that there is an excess of ascorbic acid to begin with, which is (probably) a good thing for preservation.

 

[Alan Johnson]

With Ilford Delta 100 the time from the massive development chart for HC-110 1+47 is 7.5 min 20C. Here I used 7 m 20C for contrasty subjects with PCM20 1+47.

 

[john_s]

The two shown in the pic, post 409 are kept to see what happens if the developer concentrate is just left in store so I will leave them to see if/how the crystals grow. They were clear when made up. Maybe eventually they could be re-heated to see if the crystals re-dissolve.

For a few days before the crystals were noticed the temperature dropped by about 15F to 55F.It is surprising that the PCM10 is most affected. My conclusion so far is that the occurrence of these crystals means that this glycol mix is likely to be of interest only to a few hobbyists who have a quantity of metaborate, most people would be better off mixing @relistan's formula for 512 Borax.
For actual use I have a separate mix of PCM20, not the storage samples illustrated. After 4 weeks this is still clear.

Alan, is the PCM20 batch still looking ok? If so, maybe that's the counter-intuitive approach: more concentrate I would expect to crystallize more, but if it doesn't, well and good.

 

[Alan Johnson]

John, one month since post 409 the PCM20 storage sample looks unchanged with just a few crystals .Originally it was made up on 13 Nov, post 402. So far PCM20, which is the original formula of @relistan, seems to have the closest times to HC-110 and is my preferred mix.
I am actually using a PCM20 sample which was made up 2 months ago , this is very light straw color and free of crystals.

If the storage sample lasts for a year PCM20 could be worthwhile for home brewing as all the effort is in the original mixing and after it is made up it is simply measured out one shot with a 10ml syringe. Maybe for this small grain size its rivals will be high sulfite developers that require filtering to remove deposited silver on re-use.

 

[Sidd]

With Ilford Delta 100 the time from the massive development chart for HC-110 1+47 is 7.5 min 20C. Here I used 7 m 20C for contrasty subjects with PCM20 1+47.

Looking fabulous to me

 

[relistan]

John, one month since post 409 the PCM20 storage sample looks unchanged with just a few crystals .Originally it was made up on 13 Nov, post 402. So far PCM20, which is the original formula of @relistan, seems to have the closest times to HC-110 and is my preferred mix.
I am actually using a PCM20 sample which was made up 2 months ago , this is very light straw color and free of crystals.

If the storage sample lasts for a year PCM20 could be worthwhile for home brewing as all the effort is in the original mixing and after it is made up it is simply measured out one shot with a 10ml syringe. Maybe for this small grain size its rivals will be high sulfite developers that require filtering to remove deposited silver on re-use.

This very good to hear @Alan Johnson. Thanks for carrying all that testing forward. I ran out of time after my original tests (https://www.photrio.com/forum/threads/my-pc-512-borax-developer.195379/page-10#post-2657747) and would not have gotten to this until probably later this year (house move, construction). PCM20 sounds promising. Will be interesting to see how it ages further.

 

[Sidd]

Alan, have you tried pushing films in DCM18 or PCM 20? I would like to try, but am not very confident doing so. Kindly give me tips for developing TriX 400 (35mm) @ 800 ISO, I would try DCM 18 following those.

 

[Alan Johnson]

Alan, have you tried pushing films in DCM18 or PCM 20? I would like to try, but am not very confident doing so. Kindly give me tips for developing TriX 400 (35mm) @ 800 ISO, I would try DCM 18 following those.

Sidd, I have not tried pushing with either of these. However, I note that the massive development chart gives 6.5-8 min for HC-110 dilution E , 1+47, 20C EI=400 [and 10m 23C for EI=800 seems unlikely to me].
I would start by trying 8m 20C with DCM18, at least the highlights should not be blown out, maybe some kind of test.

 

[Sidd]

Sidd, I have not tried pushing with either of these. However, I note that the massive development chart gives 6.5-8 min for HC-110 dilution E , 1+47, 20C EI=400 [and 10m 23C for EI=800 seems unlikely to me].
I would start by trying 8m 20C with DCM18, at least the highlights should not be blown out, maybe some kind of test.

Alan, let me try 8 minutes first.