I wrote an Android App last year that I felt I needed myself when I was out and about in the field photographing long exposures. I’m happy that it has now more than 2000 active installs and I have taken all comments into account and released an updated version.
As you are well aware of, most films do need correction of the exposure time for reciprocity failure to avoid underexposing your negatives for exposure times of over a few seconds. This really gets important for night photography, when using filters and for Large Format or pinhole photography. All information is contained in the App so no data connection is needed when you’re on a photo shoot abroad, on top of a mountain or in the deep countryside without any connectivity.
I do not miss the folder with printed and weather-beaten PDFs with tables of exposure correction information for the different films that I had to rely on before. 🙂
The Reciprocity App has the following features:
Easy to use and usable on Android devices of most sizes.
Lots of B&W, colour and slide film included in the App, and this list is growing with every update.
Include filter factors in the exposure time calculation.
Include bellows extension in the exposure time calculation.
Built-in timer to use the calculated exposure.
See the screenshots below.
Ease of use:
Growing number of films supported:
Details about the calculation:
In addition to the film manufacturer supplied reciprocity information, I used the findings of Howard Bond from his article in the Photo Technique magazine which had been formulated into an easy formula by Patrick Gainer.
It is a simple App, but packed with the reciprocity details of most black and white films currently being sold and a growing number of colour and slide films. Works fine on new and old Android phones as well as on Android tablets.
It’s free, make sure to grab it!
Redscale film is easy to make if you have a dark room or a change bag: Simply take all of a C-41 film out of the canister, cut it off and tape it back, back to front, and spool it back into the canister so the film will be exposed on the wrong side. All layers of C-41 film are sensitive to blue light, so the blue layer is positioned on the top normally absorbing the blue light. The result of using redscale film is a clear colour shift to red due to the red-sensitive layer of the film being exposed first as it is now on top.
You would need to overexpose a few stops to avoid having just everything in red as overexposure allows light to reach the less sensitive green and blue layers of the film. And if you are using expired film for this, you would need to overexpose even more. It is a bit trial and error.
The fun part of pinhole photography is that it is so low-tech: No real lens involved, no focussing, great results without any hassle. Or so you might think. For me, pinhole photography means that I need to bring my Android tablet, a grey-card and Sekonic 758D lightmeter to get the job done and get a predictable exposure. It is probably as hi-tech as I need to get for all of my photography. 🙂
My technique with which I have now been able to get decent and reproducible results, comes down the following steps:
Use the Film Crop Assistant app to get the location of the tripod and the composition right as you cannot look through the lens, of course.
Use the grey-card and the lightmeter to get a reading.
Use the Pinhole Camera Calculator app to convert that reading into an basic exposure time that matches the f-stop of my pinhole lens.
Use reciprocity failure correction tables specific to the film that I use the Reciprocity app that calculates the exposure time to use for a given film and metered exposure time.
Use the Timer option of the Android Clock to time the exposure.
No doubt you can find similar or better tools for the Apple world.
If you’re shooting landscapes, you would typically select a small aperture to increase the depth–of-field of your shot. Instead of focussing on the horizon, you’ve probably heard of the hyperfocal distance and you put the focus closer by to make best use of the front focus and the back focus. You might even have a calculator for this on your smartphone.
All very good, but sometimes you would like to preview the dept-of-field as you’re not interested in blurring out the background completely or getting the largest possible depth-of-field, but want to have a certain, specific to this shot level of detail in the background. Do you use f/5.6 or f/8 and make a gamble as so many details influence the result? A lot of people seem to be unaware that most cameras or lenses incorporate a button or lever to preview the depth-of-field. If you do not know that I’m talking about, check your camera’s manual and see if it supports previewing the depth-of-field. Most people have given it a try and noticed that the viewfinder goes dark and left it at that. The viewfinder goes dark as the only thing this button or lever does is to close the aperture, typically you focus with open aperture to make the viewfinder as bright as possible. But if you pay closer attention, you will also notice that apart from going dark, the background now snaps into more focus. All of a sudden it is not a gamble anymore and you see exactly what the camera will record.
Sometimes things go wrong and the results might be worth keeping. Here a few of my recent favourites:
In the above photo, I accidently put the camera in multi-exposure mode and took some long exposures from different angles. The Pentax MZ-S is a professional 35mm camera with all the settings conveniently available as switches on the outside of the camera for quick adjustments, yet it also means that you do need to check the settings when pulling the camera out of the bag.
If you work without tripod and put the camera on the railing of a bridge for a long exposure or night photography, make sure it is not a train bridge! I had put my camera on the railing of Norra Järnvägsbron in Stockholm to photograph the City Hall for this eight second exposure and the moment I released the shutter a long train came by.
I really need a better scanner that can handle the large format 4×5 inch negatives that I’m working with now, but at the moment I have no choice but to use my Epson V500 PHOTO.
For the moment I found the following solution: I scan the negative in parts and use the Photomerge feature in an old version of Adobe Photoshop Elements to stitch the parts back together. Not a great way, probably not recommended, but so far it has done the trick. 🙂
Update: I’ve now obtained an Epson V800 PHOTO scanner and get much better results.
I bought a second-hand Cambo SC2 4×5 large format camera, see here for an image of one just like it, and a Rodenstock Sironar APO N 150mm lens, see here. The 150mm lens is on the 4” x 5” negative format similar to a 50mm lens on an 35mm SLR.
This is my first photo taken with this camera and lens combination:
Not an overly interesting scene but important to me in any case as everything worked out. Large Format photography is quite different from using an SLR or a medium format camera: so many things can be adjusted. In this shot the camera is facing down a bit and I tilted the lens even more forward to increase the DOF. The back of the camera is kept vertically so the vertical lines wouldn’t fall ‘backwards.’ The image is composed on the ground glass with the aperture open using the dark cloth to actually be able to make out the details. When you’re happy, you close the aperture, meter the scene and set the exposure on the lens, insert the film holder, cock the shutter, remove the dark slide, release the shutter, reinsert the dark slide, preferably with the black side in front to signal that this side has been exposed and remove the film holder. That’s one photo done!
I posted it on Facebook and a bloke immediately jumped to the conclusion that the white reflections on the water was dust and treated me like a film newbie. So cute when that happens. 🙂
Ever since I bought my F&V K480 video light I had wanted to pick a dark location, light up just the model and create a photo with the model correctly lit but the rest close to pitch dark.
In the photo above, the light source is to the left in front of the model; I metered off her chin with my external lightmeter and used my camera in manual mode with an exposure of 0.5 seconds at f/2.8. The TTL tried to inform me that the exposure was way, way underexposed but as always, the incident lightmeter knows best. The video light is easier to use for me than an off-camera flash unit: The light I am using is available for metering and any shadows are visible while the shot is being set up, so it easy to make it work, etc..