Support our Sponsors, they keep FADU free: AG Photographic The Imaging Warehouse Process Supplies RH Designs Second-hand Darkroom Supplies |
> Splitting powder chemistry packs |
*** Click here for the FADU 2015/2014 Yearbooks *** |
|
Thread Tools | Search this Thread | Display Modes |
#1
|
|||
|
|||
Splitting powder chemistry packs
I'd like to put in a few words for powder chemistry, Ryanair and our kitchen scales. They are typical and measure up to 500g in 1g increments.
My darkroom is an old reinforced-concrete wine-fermentation tank about 2.5 x 3 metres. At some point in the last century Desperate Dan burst in (or was it out?) leaving an irregular man-sized hole. We used to travel by car between France and UK because airlines won't take cats, even with a passport. But the ferry, the diesel, the motorway tolls and the overnight stop hotel were ruinously costly for us pensioners. So when, sadly, the cat got run over we decided to use Ryanair. We don't appreciate our UK parcel deliveries services enough. We have not had good experience with French online deliveries. We usually wait for a week, twice forever. So I buy film, paper and now chemistry from FADU sponsors RK Photographic and bring it over as hand baggage. But airport security won't allow liquids so I have been experimenting with powder chemistry. The first trial was with Ilford Bromophen. The pack makes 5L, which is a bit big for 12 x 16" dish development. So I split the packs carefully to make 5 x 1L. For the smaller packet I transferred the content to a jamjar so that I could weigh the foil packet. I didn't think the weight of the larger packets was significant. Dividing the packs into small labelled and weighed polythene bags was easy. I boiled a kettle, allowed it to cool under a floating lid and mixed parts A and B into a labelled 1L mineral water bottle. I have old densitometric measurements for gloss MGIV in (liquid concentrate) Multigrade developer and the results are almost indistinguishable. My stop bath is a bit pink because it is made of red wine vinegar from the corner shop (we also use it for salad dressing). For the same price it could have been colourless (white wine?) Next stop powder fix! |
#2
|
|||
|
|||
Jo, I have often seen questions in other forums on splitting powder packs, asking if you can do what you have done. It makes a great deal of sense as powder last almost forever but alas once liquid, longevity suffers.
Usually the vast majority of respondents advise not doing it but I think this is on the basis that a lot of film developer powders are in two packs and you cannot guarantee that even if you split each pack correctly you will get the right portions of the constituents. However I assume that in a one pack powder no such problem exists and your experience would seem to confirm this. I suppose that the only possible drawback is that while the unopened pack is airtight, this airtightness is compromised and may affect longevity but as long as the longevity is still longer than the typical time taken to use up all the smaller packs of powder this doesn't matter. Even in the case of two pack developers, some claim to have successfully split them and intuitively it always strikes me that if you vigorously shake and split then there may be no reason to be concerned especially if each of the constituent parts is only critical if there is a gross mismatch of constituents in each split pack which hopefully is unlikely when vigorously shaken . Mike |
#3
|
|||
|
|||
Yes, I shook the foil packs vigorously before splitting. I am sure that the packing company (in this case Ilford's suppliers in Germany) will have made sure that the ingredients were well homogenised before dispensing.
I haven't made scientific measurements of the other four pairs of packs but I'll report if the results are not consistent. Jonathan Last edited by JOReynolds; 6th April 2018 at 05:41 PM. |
#4
|
||||
|
||||
One thing that occurs to me is that film developers need to be quite precise in their mix of chemicals for consistancy, whereas most (all?) normal b&w papers will process pretty much to completion so are less fussy. Hence, I would expect fewer issues splitting paper developers.
Shaking a packet of mixed chemicals may simply separate the contents by size and weight - shake your morning muslei and watch all the rasins rise to the top . When I separate packets, I decant the packet and stir with a spoon to redistribute before repackaging (this may be overkill for print developers tho). Do in good ventilation; you do not want to breath in developer dust - on a window sill if the wind direction is consistent. Cheers, Bob. |
#5
|
|||
|
|||
I once punctured a bag of D76 losing some. I simply weighed what was left calculated the necessary water to make it up. It's a one pack mix unlike ID11 so I prefer it. Bromophen too which is my preferred general purpose paper developer. It's very energetic, as fast as the old Ilfospeed, and works fine in cold weather, in warm weather I dilute it further than 1:3 and it still works fine.
Colourless spirit vinegar, often known as "non brewed condiment" makes a good stop bath and is often found in large catering size containers, a friendly fish and chip shop or someone who uses a cash and carry should be able to get it. |
#6
|
|||
|
|||
Powder developers
Developers like ID11 or Bromophen have a good life if mixed and stored in glass bottles. Even part full seems to have no problems. Yes it does go off but after a long time.
What I am trying to say is if you can mix all the powder in one go. If you do try this I would recommend mixing the powder in water which is around 25-30 degrees C which will allow the crystals to dissolve more easily. I have a half 500cc bottle of ID11 from which I used a 125cc (diluted 1 to 1) week ago and it was perfectly normal. Even C41 colour developer can be mixed as a full kit and stored exactly the same. My current C41 was mixed in July last year and it is good to use. |
Support our Sponsors, they keep FADU free: AG Photographic The Imaging Warehouse Process Supplies RH Designs Second-hand Darkroom Supplies |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
powder fixer | big paul | Chemical formulae | 7 | 27th December 2017 09:31 AM |
Albumen powder | kev curry | Alternate printing processes | 14 | 21st March 2017 12:11 PM |
Sample packs available from anywhere? | Terry S | Photography in general | 1 | 5th June 2012 10:15 PM |
Powder fixers? | Miha | Monochrome printing techniques | 22 | 14th March 2011 06:45 AM |
Dry Powder Ilford ID-11 | Shane D | Manufactured brews | 12 | 23rd July 2010 10:35 PM |