Saturday, 30 June 2012

Adox in PMK Pyro results.

Test stips at twenty and ten

The results are in! This has turned out to be one of the most exasperating tests to date. There have been problems all along the way from getting the exposures right to developing the film. Having said that there have been some surprises.

As with the Agfa test the film was exposed at box speed ISO 100 in the Nikon F5. This is where the process changes apart from the test method. The PMK Pyro used was one I made from raw material that did not include EDTA disodium in the mix and a reduced amount of Sodium Metaborate in solution B.

Sequence of development:

         Pre-soak - it makes no difference with this film. It is not prone to air bell/bubbles sticking to the film.
         Developer - to be made up immediately before use at 21 degrees C.
         Development times - for this test were 5, 10, and 20 minutes respectively.
         Tank inversions - continuously for the first minute and then once every fifteen seconds.
         Stop, Fix and wash - as normal.
         After bath - was not used and would have made little difference with this mix.
Adox CHS 100 PET 35mm is not like other black and white film it has a noticeable thinner film base which is coloured blue. The cassette this film came in was not light tight which almost ruined the test. I only discovered this after the film had been exposed, when removing the film from the cassette it fell to bits. I have read a forum thread saying that the 120 roll film has the same problem. Adox you need to up your game! It is appalling quality control.

Pre-soak water after use
If you use a pre-soak the water will come out blue.

The ten minute development time is the one suggested by Digital truth, which made it the reference time the other test strips were to be judged against.

All the test strips including the one thats a no show.
The test strip to show the best density of negative is the twenty minute one, having said that they are still a bit on the thin side. This does not take away from the fact that they are fully toned and well defined. There is no sign of grain when enlarged to 485 mm (19”) by 340 mm (13.5”). When printing the negatives I'm having to use grade three, normally I would expect to be using grade two, this could be due to the lack of EDTA in the mix of Pyro used. I'm also disappointed that the five minute test strip shows no negatives at all, from previous experience the shorter/half development times have a faint out line. In this case I can only put it down to the faulty film cassette. The ten minute test strip is very thin when compared to the Agfa test strips it is thinner than the half development time. Which suggests that normal development in this case should be greater than twenty minutes.

Over sized enlargment

With all the time and effort put into this test the last thing I was expecting was to be let down by bad manufacture. Of the thirty six exposures on the film around about  ten frames are unaffected by some light damage luckily the majority of these are from the test exposures that put in an appearance. If there was going to be any question marks I was thinking it would be from the developer but it did not disappoint, the only thing to note was when i poured it from the developing tank it was a lovely pink rose colour.

Will I be using the film again? Yes! only because I have a roll of 120 on the shelf if the negatives show any light damage then I will not use it again. How can I say that when I use a lot of out of date film? With out of date film at least you know that the results could be iffy. You don't expect it from new in date stock.
Used PMK Pyro.

Wednesday, 27 June 2012

Making up PMK Pyro from Raw.

This is the first time I've mixed a developer from scratch. I find when  preparing for something that is new, it seems to take an inordinately long time to set up. This has been no different and I can understand why more people do not mix for themselves.
Before you start.
If you have just purchased new scales it is a good idea to check how accurate they are. First thing to do is place the scales where you plan to make up the mix and zero them.The table that follows is a simple and affective way of checking the accuracy.

These weights came from the royal mint:

Coin test
        ●         1p – 3.56 grams.
         2p – 7.12 grams.
         5p – 3.25 grams.
         10p – 6.5 grams.
         20p – 3.0 grams.
         50p – 8.0 grams.
         £1 – 9.5 grams.
         £2 – 12 grams.

An alternative to using scales is the Twenty P mix. This is where twenty p coins are used as a counter balance to weighing out the powders. While talking about alternative ways of measuring out you can use measuring spoons. This could be a more reliable way of ensuring that each mix is consistent. If you measure out the chemicals with number of spoons it will not matter that the powders have changed in volume by absorbing moisture or drying out.

With the checks out of the way what next? How much are you going to make up as stock solution? I know from previous use that it will keep for a very long time, even years. I personally prefer only to have small amounts of developer on the shelf ready for use. This is partly because I use several different film and paper developers.  Anchells Darkroom Cookbook  suggests that you make up part A at 750 mls and part B at 1400 mls; well that is a large amount for a first mix not only that what happens if you get it wrong  or heaven forbid it does not work. Luckily Trevor Crone has published the weights for a smaller amount:

Solution A to make 250mls:
         Metol 2.5 grams
         Sodium metabisulphite 5.0 grams.
         Pyrogallol 25.0 grams.

Solution B to make 500mls

         Sodium Metaborate 125 grams.
Stock solution should be made up with distilled/de ionised water. EDTA-disodium is an optional ingredient It adds gold tone to the silver of the film.

Trevor suggests a reduction of 10 grams for solution B to help combat separation when mixed. He has also said that to his knowledge it has not affected the quality of his negatives.  I can confirm the drop out is reduced but I think this is mainly due to the reduction of powder. Although these quantities are more reasonable  I made my batch up at half these weights.

Other bits
Paper cup cake holders are a good idea for pouring the powders into when it comes to measuring out but they will only cope safely with small weights. You can get plastic cups to do the job which maybe a better route to take if you plan to mix all your own chemicals.

Common sense should prevail when it comes to measuring out these powders. Gloves and a breathing mask should be the minimum safety precautions taken. If the powder gets air born it will irritate the lining of your nose. Also if you get it on your hands it  will irritate or burn your skin. So please be sensible.  

Adox CHS 100 Pet ISO 100 35mm flim.
Developed in PMK Pyro,
Printed on silverproof paper,
Developed in Ilford warm tone.
Having purchased all the ingredients to mix it myself, is it more cost affective? The over the counter premixed price of PMK is about £9 for 10 litres. The cost of all the ingredients is around £39. The batch that I made up  was equivalent to ten litres and saved about 50p. Taking every thing into account scales, time, safety etc. etc., it may not be worth all the trouble and money as a one off. There are advantages to this method such as the flexibility of making up the quantities of developer, stop and fix you require and being able to try out other developers you would not normal be able to get from the mainstream. The main purpose for me was to ensure a ready supply of PMK Pyro. Now that I have started down this road as my stop,fix and other developers run out they will probably be replaced with powdered formulas.

Acknowledgements and Thanks to the following:

Paul C, for the royal mint weights. 
Mr S. Nichols for the 20 P mix.
Trevor Crone for the reduced PMK Pyro mix.

Saturday, 23 June 2012

The Focus finder.

This is a wonderfully simple piece of darkroom equipment. Basicly it is a magnifying glass and mirror. It provides the user with the optimum sharpness for the enlargement by focusing on the grain of the negative. 

Also known as a grain magnifier it rests on the masking frame where it diverts a small amount of light from the projected negative to your eye as you look through the small magnifying lens. With one hand on the focusing control of the enlarger you gently turn the knob until the grain becomes sharp in the mirror. This translates to a sharp image at easel level; to maintain this accuracy a piece of waste photographic paper should be placed in the masking frame with the magnifier on top. It is easiest to focus on the grain with the enlarging lens set at its widest aperture and then re-checked at the working aperture. To make sure that the focus has not changed. 

Some focus finders can only be used in the central area of the projected image. This is because the angle of the light is more severe at the edges and corners. If you wish to check these areas to make sure that the whole negative is in focus you will need a magnifier that allows for this with a wider mirror and tilting aim.

Monday, 18 June 2012

Post cards from the Humber!

Recently I teamed up with my wifefor a bit of an experiment and road trip. I loaded the Olympus mju compact with a roll of eight years out of date colour film. The idea was to share the camera between us taking pictures as we went along. Once the roll was finished I took it in to be developed at snappy snaps. No special instructions were given. The results speak for themselves. What if the film had been blank? Notch it up to experience and move on. Wouldn't it have been a waste of time and money? No! we still have the memories of an afternoon well spent, plus we had the 'mystery' to look forward too!


Saturday, 9 June 2012

Light meter.

The weather has been great this past week and not one to pass up such a rare opportunity I have moved my office to the end of the garden where it is shaded  by some silver birch trees. If it was not for the shade I would not be able to see the computer screen.

As you know from previous posts I have become quite smitten with my Zero 6x9 deluxe camera. It's lack of through the lens metering! Your right no lens, I have had to revert to using a hand held one. NO! I'm not going to take another camera with TTL with me. Why load myself down, believe it or not even with a tripod it is lighter than my standard kit. Besides I don't need the light readings to be that spot on especially when needing to account for reciprocity.

While writing this I'm joined by a baby starling. It looks like the one I saved from the jaws of the cat the other day. The bird seems happy for me to be here as he/she walks up to and around the chair I'm sitting in looking for local delicacies. It appears I'm the last thing it needs to worry about.

Two types of hand held light meter
I have two types of meter to choose from they are tried and trusted run of the mill units. The oldest one uses a selenium cell which is a type of photovoltaic / solar cell. When the front of the meter is exposed to the light it produces a small current which moves a needle that indicates how much light there is. This type of meter is batteryless but one of the down sides is in low light situation it requires a certain light level to read accurately.

The other light meter is a CdS unit or Cadmium Sulfide cell that has a greater low light sensitivity. This light meter works by regulating the energy in the battery rather than producing a current as in the former. With this type of meter it can suffer from drifting this is where the meter has been shown a bright light temporarily making it blind. The cell has a memory and can fool you into thinking the level of light has not changed. It is a good idea to let the meter read the scene for several seconds to make sure it has read it properly.

Note the starling casting a
critical eye over the
Todays meters do not suffer from this they use silicon blue or gallium arsenide photocell coupled to a memory chip  so are unlikely to have a time lag in changing light conditions.

My light meters are general purpose, they read reflective light from a fairly large area of the subject which is about 30 degrees. They round this reading to an average of 18% ( a mid grey) no matter how dark or bright the scene is. This is where the zone system ( See Ansel Adams The Negative for more info) comes into its own or a system of your own to allow for it. I have my own method that works well with a little bit of intuition thrown in. Well! Most of the time.

Since writing this my CdS light meter has passed away. It will be missed.

Wednesday, 6 June 2012

Pyro PMK Raw what is needed

I have been purchasing PMK Pyro as a set of pre-mixed powders just like ID11 and D76. Two of the most popular mass produced powdered film developers; just add water and away you go. Recently I have needed to replace my stock of PMK developer so went to Silverprint my regular supplier to replenish the stock, only to be told that they no longer did mixed batches for sale over the counter. They advised me they stock all the ingredients for self mixing. This took me aback, several expletives entered my head (which were not expressed) what was I going to do! I have a number of tests planned for developing other makes of film let alone the projects on going.

Raw chemicals to make up PMK Pyro
I raised the question on the film and darkroom forum and after the responses  came back (thank you all) I decided to buy the individual ingredients; it is quite expensive to set up, partly due to the way the powders are sold but should make it cheaper over time. This raised the thought of making up all the chemicals I used in the darkroom from powder, meaning they will be as fresh as possible at the point of use. 

What will you need? To start with a set of scales, they do not have to be that expensive but should be able to read very small amounts. The relevant powdered chemicals which are, Metol, Sodium Bisulphite (Sodium metabisulphite), Pyrogallol, EDTA di-Sodium (optional) and Sodium Metaborate (Kodalk).

Monday, 4 June 2012

Adox art series to be developed in PMK pyro.

Adox art series CHS 100. ISO 100

It has been a long time since I mentioned that I was going to do a test development using PMK Pyro on Adox  CHS 100 art series. What with the weather being unseasonally wet and other things getting in the way I have not been able to do the test exposures. I prefer to take the pictures outside on a bright day without fast moving clouds. Something that has not been forthcoming. The light level needs to be constant for the eighteen frames it takes to produce three test strips of two F numbers over and two F numbers under the metered reading. 

I'm pleased to say that the other day, weather and time to expose the film coincided which has resulted in a film waiting to be developed. Something that requires a spare four hours to do whether all in one go or over several days. See Agfa test formethod.