Tag Archives: Contrast

Are your film negatives good enough?

Are your negatives ‘good’?

As a film user, do you process, then scan, or do you print in a darkroom?
How do you know if your exposure and processing method is giving you the best negative for the kind of work you wish to produce?

If you use a scanner, followed by photo editing software to bring your pictures to life, you can manage with negatives that are way off the mark for exposure, processing, or both. Because of the tremendous ability of software to control and alter the contrast range of an image, many film photographers are producing negatives which are technically incorrect, then ‘pulling’ images out. I see this quite often when a picture is put online in an Face Book group, Twitter, or shared on Google +, I can see at a glance if a shot has poor shadow detail or is overdeveloped. Recently, someone had posted two images and had also included the negatives. It was obvious that the negatives were two stops underexposed, but the photographer was showing the shots as examples of his great talent.

Last year I did a little research into stand development and in a few places on the web there were photographers claiming that all monochrome films could be stand developed in Rodinal for an hour and all of them would be perfect. yesterday I watched a video in which the photographer claimed that two hours was the correct stand time for Rodinal. It didn’t take many films for me to realise that these opinions were started and perpetuated by people who were not printing them in a darkroom. When you print your negatives in a darkroom, you very quickly find that poor exposure and development of your negatives causes difficulties in contrast control and tonal representation. The better your negatives are, the easier and more productive your printing session will be.

So how do you know if your negatives are good?
A difficult question to answer using only the written word. Depending on subject matter, the negative should have a range of tones that run from clear film base, through the tones, up to areas of quite dark grey. You should NOT have any areas that are jet black, even if the subject or scene has the sun in the sky. If you have solid black, you have over processed, either by having the developer mixed too strong, or the temperature too high, or by giving it too long. Beginners often give their films longer in the dev because they are worried about not having anything on the film, but they create negatives which are a real headache to print. Many beginners don’t realise they are over developing, because they like the contrasty look that they get. High contrast negatives can be very creative in the right hands, but how many of us have the graphic vision of Bill Brandt, or Mario Giacomelli? Both of these photographers overexposed and over developed their film (grossly overdeveloped, in the case of Giacomelli), but made very strong work.

The way to prevent over dense negatives is to lower your dev times. This is where beginners start to panic; What if I cut back too much and there is nothing on the film? Well hopefully the detail and tone has been established by proper exposure, so you would have to cut back development severely to lose it all. Taking your processing time down by 25% will make a difference, but won’t lose the images unless your original time was wrong in the first place.
If you are a darkroom worker there is a simple test which will help you determine if your exposure and development regime is within acceptable limits (whatever they might be). Of course this can come down to personal taste, but this sequence will help you get it nearer to the middle mark.
Load your favourite 35mm film into your camera and find a normal scene with a good range of tones. Take a meter reading in the way you normally do and take a shot underexposed by two stops. Take the next shot one stop underexposed, then one at the indicated exposure. Follow this with one frame shot at a stop over and the next, two stops over. You now have a bracketed sequence of five frames with the indicated exposure in the centre. Repeat this sequence until the film is finished. (it is worth wasting one film on this, as it will clarify a number of things).
In total darkness, pull out the whole length of the film and cut it into three roughly equal sections. Load them into separate developer tanks (or, if you only have one tank, load one and store the other two bits in something totally light tight until your tank is clean and dry).

Now develop the first length of film at 20% less than the time you would normally use, keeping temperature and dilution the same. The second section of film should be processed as you would normally do, and the third section should get 20% extra dev time.
When the films are fixed, washed and dried, a contact print should be made of a five frame sequence from each of the three strips. The important thing though, is to realise that you must expose these for the shortest possible time that will give you a black under the clearest parts of the film, ie; the edge of the film, or the gaps between frames. So, your test exposure and the way you read it, must be done in a way that will give you this information. The exposure should be the same for each of the three strips. When the time has been established, contact all three strips (or sections of) on the same piece of paper. Look at the finished contact print and see which frame gives the best representation of the full tonal range of the scene. There should be one frame that looks right and some that are too flat and others that are too contrasty. This will tell you how far out your exposure or processing is. Try that frame as a print, using the same criteria that you used to judge the test for the contact sheet; Choose the first exposure that gives you a black in the clearest part of the film. Check the test, the highlight detail should be the same as the contact sheet. Make a full print at this exposure and compare it to your previous work. Adapt to the new information and establish a repeatable method for creating good negatives from that point forward..

 

Good luck with it all and let me know how you get on.

Is your metering method causing you problems?

Following on from my previous post on comparisons between meters, I thought it important to point out that HOW you use your meter has a significant effect on the exposure you get on the film. There are basically two ways to meter a scene, but a few variations on how those measurements are actually taken and interpreted;

The two main ways of taking a light reading are Reflective and Incident. Reflected readings are measurements of how much light is falling ON THE SCENE and Incident readings are measurements of how much light is falling ON THE METER. Spot meters measure small areas, but are still reflective types and when you take a reading through the camera lens (TTL metering), you are also taking a reflected reading. The trouble is, your choice of subject, or the angle that you shoot from, will influence the brightness that the camera reads. For instance, If I point my camera at a bunch of trees from thirty feet away, I will probably get a reasonable reading from the camera. If I then walk up to the nearest tree and lie underneath it, pointing the camera up through the branches at the sky, I will get quite a different reading, even though the light levels are the same.

In another scenario; I have in front of me two garage doors. One of them is painted black, and the other is white. If I stand some distance away, my reflective reading will average out the lights and darks, giving me an exposure somewhere in between. If I then walk towards the garage doors and take a reading from each, I will have TWO OTHER readings, even though the light levels are still the same.

This kind of subject influenced reading happens on sunny beaches, snowy landscapes, stage photography, night photography, or whenever you photograph any object, scene or person with a predominance of dark tones, or light tones. Given the infinite range of everyday lighting situations and possibilities for error, it is amazing that most shots come out at all. The reason they do, is because film is so forgiving, especially if you are scanning from your negatives and working on the images in photo-editing software. When I say film, I am referring to black and white, or colour negative films. Colour transparency film is far less forgiving and needs more careful metering.

The other method of metering  I mentioned was the incident reading. With this, there is usually a white plastic cone which goes over the light cell and this then allows the meter to read the light falling on the meter, and this is not affected by the tone of the subject. Incident readings are a quick and very accurate way of establishing a reading and are correct in most situations. If used in a back lighting situation, they will favour the shadow tones and give you an exposure which will show the lit areas as overexposed, so use them intelligently.

There is one rule when taking incident readings, and that is that you must point the cone from the scene towards the camera, -not towards the light source. The reason the white thing is a cone, and not a flat disc, is so that in side lighting, one side will be lit and the other shaded, the meter can then average them out. If you point the meter at the light source, it will not take shaded areas into account and you will have an underexposed shot.

Screen Shot 2015-08-31 at 16.57.05

If you have a meter with the facility for taking both types of reading, you can take two readings beginning with an incident, then decide if the reflective is giving you a proper mid tone. I usually take an incident and check that against a reflective reading off the grass, or tarmac on the road, both of these are very close to mid grey.

In certain weather conditions, fog for instance, or snow scenes on a grey day, the light remains constant for a number of hours and one meter reading will be sufficient for many shots. Take one incident reading and the light will be the same for every shot.

Screen Shot 2015-08-31 at 16.51.51

Spot metering. The spot meter is an excellent invention, but needs careful thought when being used. Typically it will take a reflected reading from a small area, indicated by a circle in the viewfinder of the meter. Anything outside of this area will not be metered, though they do pick up a bit of stray light if you have areas of brightness nearby, or are pointing into the light.

Some people think that all you have to do is take one reading from the shadows, and another from the highlights and put your setting right in the middle. This can be done, but it will depend on how high your bright areas go. Are you reading off a white painted door, or the clouds nearest to the sun? A far more accurate way to do it is to read the exposure for the darkest tone that you would like detail in and underexpose from that reading by two stops.

The important thing to remember is that exposure determines shadow detail and development determines highlight detail.

Just let that sink in a bit; Exposure determines shadow detail and development determines highlight detail. There is no shadow detail that can’t be rendered on film if given enough exposure. Leave the shutter open long enough and the film will record light that your eyes cannot detect. Okay, we’ve got that, but what about contrast? Well, if you have exposed so that the shadow detail will produce some pale greys on the negative, but you have areas where a lot more light reached the film, say for instance, a gap in dark woodland with a sunlit area beyond, this area will have obviously received an excess of light. This will only become unprintable if you keep it in the developer long enough for it to go to black. You don’t want that, you want a dark grey that you can print through, so the answer is to cut back the developer so that this doesn’t happen. I’ll be covering this subject in my next post.

Metering through the camera lens (TTL). This is a quick and practical way to get your exposures pretty close to correct as long as you understand a few things; What you point the camera at for the picture, doesn’t have to be exactly the same thing you point it at to take a reading. For instance, if you were shooting tall buildings in the city from ground level, you would most likely be pointing the camera up and getting lots of sky. Point the camera at the building, excluding sky, take the reading and use that for the up shots. If you are shooting a band on stage, exclude the lighting rig from the frame when you take the reading, then set it and fire away.

For street shooting, a 35mm camera is ideal, but you won’t have time to take a reading as you compose the shot. Think about the tonality of the scene, take a reading from something typical, then set it and forget it.

Metering in low light.

Metering in situations where there is low, even light only requires a good incident reading, a reciprocity chart and a tripod. Metering in situations where there are areas of deep shadow, coupled with hotspots of intense light, such as a concert needs a different approach. Uprating is commonly used in these situations, but this creates negatives of higher contrast, requiring very careful metering. Whenever I see images online and the photographer is claiming that the film was rated at 12500 ASA / ISO or some such high number, my first thought is; Yes, but where did you meter from? If the shots are taken at a concert, or some dark restaurant or club, there will be areas of deep shadow and very bright spots of light. In that kind of situation, a 12500 ASA reading from dark clothing in the corner of the room will give pretty much the same exposure settings as a 400 ASA reading from a well lit face. TTL metering will give you a result, but if the shot is important, then a carefully taken incident reading would be better.

Outdoors in changeable weather conditions: If you have one of those days when the sun is in and out every two minutes messing up your readings, remember that the exposure will only drop by one to one and a half stops when a small cloud comes over. Proper storm clouds will take much more light away, but a typical British summer day with fleeting clouds is easy to meter; If you meter the grass for the sunny areas, the shadows from the clouds will be 1.5 – 2 stops darker than mid grey, but if you meter for the grass when the cloud comes over, the sunny patches will be 1.5 – 2 stops brighter than mid grey. Meter the scene according to the look you are after.

Go out and try these methods and let me know how you get on. If there are any other lighting situations you are having difficulty with, then please leave a comment or question.

 

Flexible film

First posted 19 October 2009

Different photographers have different expectations from a film. They may buy a particular brand because they have seen that someone they admire has used it, or because it is a new type. Some buy films looking for good latitude, others for speed, acutance or fine grain. Others may be expecting contrasty, gritty results.

Buying a film and exposing/developing at the manufacturers recommended settings will usually produce negatives that are a compromise between all of these expectations. Producing the results you really want depends on an understanding of what happens when film is treated differently.
One of the first ways that new photographers try to get different results is by uprating. They read somewhere that a 400 ISO film can be exposed at a higher speed such as 1600, and then stewed in the dev to bring up the image.
This does indeed work, but occasionally at the expense of quality (not always a concern for some). Uprating can produce quite acceptable results with dilute/static processing (see the section at the end of this article) and I have rated Ilford HP5 at 1600 ISO and got results almost as good as when rated at 400.

But if the developer is one which is vigourous, the grain can be exaggerated and contrast can increase to a point where printing becomes difficult and burning in highlights is impossible. This is not always a bad thing, if you look at the work of Bill Brandt you see what can be done creatively with a film which is mistreated in this way.
Going the opposite way, if a film is downrated a couple of stops and the development time is reduced, a finer grain and a longer tonal range is produced. This can look absolutely stunning with larger negatives, especially when photographing subjects with a lot of subtle highlights such as sunlit clouds, or snow scenes at night.
The importance of agitation.
When I did lots of different ratings and development times in the early years of my career, I also found that agitation could alter the look of a negative.
Normal agitation is usually taken to be three inversions of a tank every minute and increasing the number of inversions/agitations will increase contrast. BUT, taken to an extreme, with continuous agitation, contrast actually drops!
I think it is because the developer is not allowed to sit on the surface and work properly when constantly in motion, -but I’m not a scientist, I’m a photographer, so I may be wide of the mark there.
Whatever the reason, there is a marked drop in contrast with continuous agitation as I have just mentioned, and when coupled with downrating produces a negative which has amazing latitude for highlights or overexposure. This means that a reading can be taken from the shadows to ensure detail, and the highlights will never be blown out.
Here is a composite image of four frames of the same film, The film was Ilford HP5 and the developer was Ilford ID11 stock solution at 20C with continuous agitation for four minutes.

all four

These frames are; top left 100, top right 50, lower left 25 and lower right 12 ISO. As you can see, any of these frames could be printed. From this you can understand how the technique could produce a ‘flexible negative’ (to quote my late friend Barry Thornton), and therefore how well they could compress a high contrast scene.

Dilute/static development (also known as stand development, though there are many different methods of this).

Mix up a 1 – 3 solution of Ilford ID11. That is, one part of stock solution (normal strength) mixed with three parts of water.
Get the temperature to 20C
Pour into the tank and agitate ten times.
Start the clock.
Give three inversions every 30 seconds up to ten minutes.
When ten minutes have passed, put the tank down and do not move it at all for 50 minutes. Try to keep the temperature fairly constant.
When that time has elapsed, agitate the tank three times and repeat this agitation each minute.
After ten minutes pour the developer away and use a normal stop bath (Not too strong, weaker is better).
Fix as normal, wash and dry.

With this development method, Ilford HP5 can be rated at 1600 ISO and can produce very good results.

Here is a scan from a 10×8 print made on a Grade 2 paper from one such negative. On the print you can see detail in the dark corners and the sunlit highlights.

 Train carriage