To meter or not to meter …

I promised in a recent post to share my metering approach when using the 5×4 camera and as the weather here is disgusting at present what better time to do so. I’m also very aware that my last dozen or so posts have been very “dry” too; which it certainly isn’t outside!

Pre-amble

Why did I specify 5×4 and not just generalise? Well, my approach differs depending on what camera I’m using and how I’m using it. With pinhole photography I’ve found that a reading taken with the App on my phone, adjusted for reciprocity and with a bit added on for luck gets me where I need to be pretty much every time. I’ve written before about how I use my Horizon S3 panoramic camera and my metering approach there is based on an initial reading as I leave the house which is adjusted based on experience so that I can enjoy the free-flowing experience of using that camera.

Similarly, on the rare occasions that I use an SLR, typically a Nikon F801, I make use of its onboard meter, putting the camera in aperture-priority and only interfering with what the camera determines when I have a specific need to. When using the Bronica cameras handheld I usually adopt the same approach as I do with the Horizon S3 but when I take the trouble to lug a tripod about I automatically default to my 5×4 methodology which is what I’m going to talk about here.

Now, my current methodology has not been a tried and tested system that’s worked unchanged for years but has been evolving over those many, many years. Over the last few years however it has gradually settled into a more consistent approach using a spot-meter. Realising that I had settled into a set routine in the last twelve to eighteen months I recently decided to harness this further by formalising my note-taking so that I had all the information at my finger tips when getting ready to develop the films or when reviewing the negatives on the light pad.

In the field

Ready to “read” the scene and calculate exposure settings

Every DDS has a post-it note on the back with the holder number and the film it contains written upon it. This helps me determine between empty and loaded film holders as well as being a reminder of what is loaded. I scribble brief exposure notes on these at the time (f32 1/15 for example) but I also make more detailed notes in an A5 notepad I carry with me. Once home these scribbles are transferred to an A4 sheet which captures and organises the information in a logical fashion. One thing I always do in the field is a rough sketch of the composition on to which I write/scribble the spot-meter readings. The example below has a recent innovation … a picture of the scene captured with my phone (see above) to replace the pretty rubbish field sketch I made at the time.

Whilst this sheet is for a couple of glass plates it is exactly the same method that I use for film too.

The numbers on the image of the scene represent the spot-meter reading for that part of the scene. They represent the EV value for that area given the speed of the film in use. I take a series of readings from around the scene making sure I capture areas of highlights, shadow, middle tones and particularly the darkest area of shadow where I want to be able to see some detail in the finished print. Many of you will realise that this approach uses the Zone System as it’s basis and if you’re not familiar with this method I’d encourage you to check it out in more detail. For me, these readings, give me everything I need to calculate the exposure I need.

For the scene above I was keen to retain some of the details in the area at the base of the building which has been painted black. There was a lot of small details there such as a ventilation grill, gas bottles and other detritus and I wanted these visible rather than an amorphous lump of black shadow. The EV reading was 9 and so that gets plotted on the grid to the left as Zone III. This is the lowest zone that will render texture and detail in a print. Where we “place” this value on the grid is as much an aesthetic choice. I could have chosen Zone IV for example and brought out even more detail but for the image I had in mind I chose Zone III.

The next thing is to determine what the range of tones is in the image. My method is to simply count down the grid and seeing on which Zone the highest EV reading will land. In this example EV 14 lands on Zone VIII which is perfect for my needs. This gives a full range of tones which are also within the tonal latitude of the film. Had the highlights fallen on Zone IX or higher then they would have been completely blown out with no detail visible in the print. A choice would then need to be made in this case – whether to sacrifice the shadows, the highlights or to expose for the shadows but make a note to adjust development time to bring the highlights back into the tonal range. As this doesn’t apply here we will leave development adjustments to a later date and a later blog post.

So, I now have all the information I need. I know where my shadows need to be for my creative intent and I therefore know where Zone V, or 18% grey, sits. I also know that the full range of tones in the scene can be captured with out needing to make any adjustments in development. So where do I get my aperture and shutter speed from?

Well, depending on my aesthetic intentions I firstly choose either the aperture I want to use or the shutter speed I need. In this example I wanted everything sharp across the scene so I chose an aperture of f32. I then take my Zone Wheel from my bag, a high tech mix of cardboard and metal work, and setting the readings on the discs I can read off the necessary shutter speed.

Mr J Martin (junior) kindly made my Zone Wheel

So, the EV value 9 has been placed alongside the Zone III marker, see how the other EV values slot in just as they did on my grid? Look at the bottom and you will see a range of f-stops. I wanted f32 which, reading off the time opposite gives me half a second. I wasn’t using any filters and reciprocity isn’t a factor at this shutter speed for this emulsion so my base exposure becomes 1/2 second at f32.

At this point I could adjust matters if I thought 1/2 second was too slow, for example, on a blustery day when I wanted no movement in the image, but these changes are just extrapolations of the base exposure. I could open up to f8 for example at 1/30th second for the same overall exposure.

My final decision is whether or not to tweak the exposure based on my experience. However, the exposure we’ve calculated will give a good result so it is not an absolutely necessary step. In this instance I was using a dry glass plate and my experience with these shows that an extra stop would do no harm and therefore I opted for a one second exposure at f32.

Back home

Back home I try to sit down with my holders and my notebook and a supply of blank forms and write everything up as soon as practical. The scribbles in the notebook provide most of what I need, but I have the post-it notes as a back-up and by doing it whilst everything is fresh in my mind I can capture some of my thought process too. If I need to adjust development times I note this in large letters on the form and also on the post-it note which will stay with the film holder until the sheet of film is transferred to the developing tank.

Once the films have been developed the post-it notes and on location scribbles get put in the recycling bag and I file the A4 sheets along with the negatives in a ring binder so everything is together where it can be referred to as required. When it comes to printing the negative in the darkroom the reverse of the form can be used for printing and development notes – one day I will formalise these too!

So, there you have it. I have tried to keep this focused on the practicalities of calculating exposure in the field but there is plenty more to learn. I have referred to the underlying principles which relate to the Zone System and would recommend further reading as a full appreciation of this methodology will help you to use this approach more successfully in the field.

FOOTNOTE: whilst many people decry phone-based metering apps I’ve found the one I use to be reasonably reliable. In the example above the App suggested 1/4 second compared to the 1/2 second I calculated. Bear in mind that I was specifically looking to hold detail in a small area of shadows and you will see that it isn’t a million miles away.