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On processing: developing black and white films, and what can go wrong

On processing: developing black and white films, and what can go wrong

There are plenty of guides explaining how to develop black and white film. There are books too. French speakers: the best source of information is Philppe Bachelier’s classic “Noir et Blanc”. On my shelves there is also The film developing cookbook which is good but I prefer Bachelier’s book.

Daguerre was here

So why yet another guide? Well, one of the wonderful (I mean it) things about film is its unpredictability. Things will not always go perfectly. Here, I wanted to write down a few things I’ve learned myself over the past few hundred rolls. At the same time, I thought it would be a good idea to centralise some of the most useful information I’ve found. You see, after all this time talking about film a few friends have said to me, well, I’m interesting in developing film, do you have any hints? Great! Of course, this text is not meant to be prescriptive. This stuff may not work for you, yes, it may burn down your house and eat your cat. The thing about film development is there are a lot of variables, and unfortunately experimentation is essential. But here’s what I’ve learned…

So, if your aim is to get a perfectly developed negative free of blemishes and artifacts (i.e., you are not a Japanese photographer making photographs for Provoke magazine in the 1970s), then here are a few hints. I am assuming you know about the basic steps: loading the tank, developing, stop bath, fixing and washing. That’s easy (and the Kodak and Ilford website have a mountain of great information like this guide for example). But there is more …

These guys didn’t care too much about shadow detail (from the recent “Provoke” show in Paris)

Some general comments about developing and agitation

It’s important to select a development time which is at least five minutes or longer: shorter times are difficult to control accurately because you may spend a significant fraction of that time filling or emptying the tank. To figure out your times, the Massive dev chart is a good place to start as any, although adjustment will certainly be required. I keep a note on the computer where I record times and agitation for every film I develop, and this has been fantastically useful understanding when things go wrong.

Also pay attention to the minimum amount of chemicals required for development (e.g, you need around 6ml of HC110 and 6-10ml of Rodinal per film). Check the manufacturer’s data sheet for your developer. This means that for higher dilutions, i.e, 1+50, you may need to put in more water than is needed to cover the reels. It may not be obvious how to select the correct dilution, but for HC110 at least, with the equipment I have, I selected the dilution based on the size of the tank and development time I wanted. Changing dilutions does not seem to affect the contrast for me (the same is not true of Rodinal). Note, of course, that this developing should be done a standard solution temperature of 20 degrees (which you can check with a cheap digital thermometer). This is about right for Paris, where the tap-water usually comes out close to this temperature.

Machinery
Now that’s real processing and real machinery (in Bangkok)

Each manufacturer has a different recommendation for agitation, which is how the film development tank is turned during processing. As everyone says, pick a scheme and stick to it. For shorter development times (5-6mins), it is a good idea to agitate for at least one minute at the start of development, because you may spend a lot of that time filling in the tanks and (as I have found) this can lead to uneven development (this is the Anchell and Troop recommendation).

There is some debate as to whether or not there film should be soaked in water before developing, with some manufacturers (Ilford) suggesting that it’s not a good idea. I have not pre-soaked my films, but it might be useful if you have uneven development. Pre-soaking, as far as I can tell, can only do harm with special developers like Diafine.

Fixing and washing

I re-use my fixer and stop-bath. However, after the first forty or fifty rolls, I found it was better to use disposable bottles for the fixer (I use well-cleaned opaque plastic milk bottles) instead of always storing it in the same bottle. This is because you may get some silver in the bottom of the bottle, and if you are not careful these silver specks can end up on your film. You cannot wash them away, they adhere to the negatives. Worse, if you decide to dry your film with a squegee, it will scratch the film. So, when it’s time to renew the fixer after about 15-20 rolls, throw out the bottle and use a new one. You can find if your fixer is expired by doing a test like this.

Note added later (January 2018): After discussions with experts, the black spots and fixer precipitation that I talk about here are caused by using expired stop bath. I’m using Tetenal’s Indecit, which is supposed to change colour when it’s time to change the bath: but it doesn’t, really, and I realise now that I have been using weakened stop bath. If you do this, by the time you get to the fixing stage, there is still enough active developer around to precipitate out the fix. Solution: change the stop bath after every 15-20 rolls.

I use plain tap water for diluting all my chemicals. I tried distilled water but it doesn’t make any difference to development for the developers I use. However, in the very last step, it helps a lot to use distilled water for the final rinse with a wetting agent. For this, I buy five-litre containers of demineralised water in the supermarket (filtered tap water doesn’t work as well). This step ensures that there are no drying marks on the film from carbonates in the water. And remember, I said do not use a squegee? Simply shake the reels when you take them out of the tank and then hang them up to dry.

I saw this bus but couldn’t get on it (shot on HP5+ !)

I have tried different schemes for washing the film at the end of the processing. However, in the end I have switched to the “Ilford” method, which is fastest, and seems to work well: fill the tank, invert, dump, fill the tank and invert 5 times, dump, repeat for 10, 20 times (or less if you are less paranoid). The advantage of this method is that it uses less water, is faster, and additionally you can easily control the temperature of the water you are using for rinsing (running water from a mixer tap is hard to control).

Drying

My most-used film is Kodak’s Tri-X, and this has a habit of curling in the perpendicular direction to film. Sometimes this curl so strong that at the end your film looks like roof tiles on a house in Provence. This adds a second, lengthy step of putting your negatives under heavy books, for several hours, preferably containing good photographs. The internet has a few suggestions as to why this happens, but it seems to be related to the speed and temperature at which the film dries. I’ve found that not washing the film in super-cold running water and ensuring that it dries as slowly as possible helps reduce the curling. So don’t leave the bathroom window wide open.

Summary of things which have gone wrong … for me

Here’s a description of all the things I have had personally go wrong with my development. Of course there are even more things which can go wrong, this list is not meant to be exhaustive. Hairs and dust are the most common things you see on the negatives: I have found you can minimise this by passing a lint-free cloth over your scanner glass (if you are using a flat-bed scanner) every time you scan a new film. Small occasional defects like these can easily been removed in post-processing in Lightroom, they are obviously more problematic when printing, so carefully examine your negatives before putting them in the enlarger.

What it looks like on the negativeWhat causes itHow you can fix it
Many small black dots randomly distributed over the frame
Silver particles contaminating the final wash
Use new bottles when you replace your fixer
Small black crescents
Film was bent during loading
Be careful!
Large fuzzy black spots with holes
Water drying spots
Use distilled water in the last washing step with photo-flo
Uneven density
Insufficient agitation
Agitate more
Agitate more
Film is still slightly pink or not completely clear after washingInsufficient fixingFix longer, or renew your fixer
Very large black blobs filling the whole frameFilm was loaded incorrectly and film was touching in the spool Load the film correctly
Long straight linesFilm was scratched, either during loading or dryingBe careful !

 

How can you tell if you have done it right?

So, the last question: you have developed your negatives, and they are clean. How can you tell if you have done it right? This is the hardest thing to learn: how to distinguish between underdeveloped, overdeveloped, underexposed or overexposed film. In addition, scanning the negative can hide many things that can go wrong, because if you are not careful the scanning software will equalise all the intensity levels. Your negative overexposed by five stops will look (almost) normal, but will be very hard to print in the darkroom.

This is a great description about how to assess your negatives, with examples. This is another reason why simply looking at scans on the internet mean that it is very hard to tell what any particular developer and film combination looks like. Again, of course, it depends on your artistic intention, but in general preserving details in the shadows and not blowing out the highlights depends on finding the right balance between exposure and development time.

Contact prints at the observatory darkroom

The best way to figure out if you have correctly exposed and developed your film is to make a contact print on “Grade 2” paper, where the contact print is exposed to ‘maximum black’: the darkest part on the image must correspond to the same black level as the film sprocket holes. This is the definitive guide from Tom Halfhill. I’m lucky to have access to a darkroom, and I try to make at least one set of contact prints for each developer and film combination that I try. For darkroom printers, your aim in developing and exposure should be simply to make a negative which prints with normal contrast (good shadow detail, highlights which are not blocked) on grade two paper.

Parting words

Starting out, I hadn’t thought to write quite as much as this. But I hope it’s useful to someone, somewhere !

Bangkok (July 2017)

Bangkok (July 2017)

Here are some photographs from our recent trip to Bangkok.

First, a series of photographs taken (mostly) in and around the markets in Bangkok. It’s really wonderful taking photographs there, there are so many things to see. Returning to Paris, one feels that the city is strangely empty.
[foogallery id=”1075″]

But what did the city feel like? Something like this, I think:

[foogallery id=”1120″]

Now to post some photographs from Japan, too…

Rationality, Loach, Trump, Science

Rationality, Loach, Trump, Science

A few years ago I read John Raulston Saul’s excellent “Voltaire’s bastards”. The thesis of this book is that in the West we have fallen under the control of vast rational systems which have no underlying morality of their own. These systems allow our society to function but they function outside any moral system. The link between justice and reason has been cut, and governments use rationality as a means to justify their actions.

I couldn’t help thinking about this book after we went to see Ken Loach’s excellent new film, “I Daniel Blake”.  The eponymous Daniel Blake is a honest tradesman who loses his job after a heart attack at work. Although he has a serious medical condition, his honestly leads him to falling onto the wrong side of the benefits system, and although his doctors strongly believe otherwise, he is declared “fit to work”. But he isn’t fit to work, not really. To get his benefits, he must look for work, but he is unable to accept anything he finds, because of his medical condition.

He patiently explains these contradictions to anyone who will listen in the benefits office, but to no avail. What struck me most is the constant refrain to him from various council employees (in a strong Geordie accent): “It’s not against you, like, it’s what we have to do”. It is not us, it is the system. The refrain of the last hundred years. It’s not a big leap to go from the there to consider the results of the British referendum and the American elections. The most striking aspect of these two events is the complete disregard of any opinion of “experts”.  There are certainly a large number of reasons for that, but one that seems relevant here is how disconnected many people have become from the enormous systems that have become enormously important for our lives and well-being, and which just don’t care what we think.

Perhaps we could extend this thought a little further? Science has become even more incremental in the last few years. Part of the the problem is that any new theory of the Universe must also explain the last few hundred years of observations as well as any new ones. Each minuscule advance now requires an enormous amount of work. And these advances take place inside enormous systems which have been calibrated extremely finely to succeed. It is the old problem: you cannot build anything expensive and complicated unless you are certain it will work, but how in this case are you ever certain to discover something new? And behind that there is a system of thousands of people somehow trying to work together, in a system doesn’t care anything for the people inside it

The conclusion: I do want to suggest that rationality is a bad thing. Of course it is not ! But we must find a way reconnect rationality and reason to a sense of social justice. And as for science? That is for another post.

"Histoires courtes": photography and electronic detectors

"Histoires courtes": photography and electronic detectors

On Monday documentary filmmakers Jean-Francois Dars and Anne Papillaut published a short “film” that they made about my research and photography here.  Here is a direct link to the film.
It was wonderful working with them. It was a long process: we started in April when we recorded the soundtrack. I had carefully prepared a text. But it didn’t work at all! Faced with the microphone I couldn’t recite any of the words at all. I was completely stuck. So I just started talking about what I wanted to say in french, because it seemed easier to speak to them in French about these things (I speak in French with all of my french friends and colleagues, after all it is more than ten years that I am living here now). And that was the text that they used.

Taking the photographs 

Afterwards, during the summer Jean-Francois came to my office and took a few photographs and after thata we went into the darkroom where I developed a big picture of one of the Euclid CCDs. Jean-Francois suggested that we take some pictures at night, because I had talked about how I preferred taking pictures at night on film, so a few months later we spent a wonderful winter evening together (after a nice meal of course) when we walked around the centre of Paris and took pictures.

See the craters of the moon

Or rather, I took pictures and Jean-Francois took pictures of me taking pictures. I can’t say that I approached this with some small amount of trepidation, because Jean-Francois was a friend of Kertesz, and Kertesz took the first-ever photographs of Paris at night! However, in the end I was quite happy with the photographs I took and a selection of them are on my 52rolls pages. If you look carefully, you can see Jean-Francois taking pictures of me. It was so easy to interact with people and take these pictures, it was the most natural thing in the world. I just applied my Winogrand-inspired technique of smiling a lot, even when I wasn’t sure if anyone was looking at me or not. This really does work.

Losing the photons

The “histoires courtes” are very short, most I think are under three minutes. The text and discussions were edited to focus on the key difference between electronic detectors and photographic plates: the quantum efficiency of silver grains is a lot lower than electronic detectors. In the visible spectrum, the latest CCD cameras from e2v have a quantum efficiency in the visible bands of almost 100%. Only around 4% of photons falling on film get converted into silver grains. This difference of course had some interesting consequences: in the film era, people spent a lot of time and energy trying to increase the quantum efficiency of photographic plates, “sensitising” them by baking them in the oven and so forth. Eventually photoelectric detectors came along, but alas, they were not array detectors and so making images was impossible. The arrival of electronic array detectors was a revolution: a CCD camera suddenly transformed a 2 metre telescope to a 4 metre telescope. Now today with the very high efficiency of electronic detectors in the visible bands, the only way to increase the number of electrons is to increase the size of the primary mirror. In addition to the greatly increased sensitivity of electronic detectors offer much higher angular resolution, and in most cases the electronic detectors fully sample the instruments’ response function, so the amount of detail you can record is limited by the atmospheric conditions and not the detectors. So the advantages of electronic detectors are clear for astronomers. But for photographers?

And on film?

I already wrote about this over on Leicaphilia. To take a good picture on an average day in Paris, you need an detector sensitive to say ISO400, a lens that can do f8 and a shutter speed of 1/125s. Nothing more. Most digital cameras have been able to do this for at least a decade and a half. And if you want to print your masterwork at a reasonable size – 18×24 say – in most cases ~5 megapixels suffices. Nothing more. So, you might wonder, where does that leave the last decade-and-a-half of technological development? Well, not in the service of taking pictures…