Camera Obscura - also known in it's simplest form as a pin-hole camera, it basically consists of a light proof box with the exception of a tiny aperture instead of a lens that allows the image to be projected on to a suitable surface with the exposure being controlled by something as simple as a pivoted shutter or even a piece of black tape. The projected image is inverted and the clarity of it is usually dependent on the diameter of the hole.
Compacts - available as both digital and film in a variety of sizes and price ranges. The film compacts could anything from 110 film to 35mm and were usually of a simple 'point and shoot design that was based around simplicity of use although there was always the added excitement of you wondering whether there was ever going to be anything coming back from the processors that was actually worth looking at ...this is of course a personal opinion based on past experience. The digital age brought with it an ever increasing range of possibilities including high speed, low light and even zoom photography and has made such an impact on the industry that the DSLR can find itself left at hope on more than one occasion.
Bridge - offering a stepping stone into the world of RAW and digital SLR photography, firstly by taking on the physical shape and secondly by allowing a good range of macro to zoom photography. Bridge cameras have come along way since their initial introduction.
SLR/DSLR - without going into all the finer details of full frame and cropped sensors etc etc , the dslr is basically the natural progression from the old 35mm single lens reflex camera. They have a flip up mirror that allows the photographer to see exactly what he is planning on shooting through the lens, before releasing the shutter which is when the mirror flips up and allows the image to be captured on either film or sensor. Available in whole host of price ranges with a full range of lenses to suit the purpose and capable of a terrific range of fast action, low light and zoom photography depending on your needs....and wallet.
Twin Lens Reflex - is a medium format camera that takes 120 film and offers a twin lens set up one of which allows the image to project onto the the film whilst the other offers the photographer a view, by way of parallax and the image seen is back to front.
Medium format - again available in both film and digital versions and with digital conversions also available for film formats although they are ridiculously expensive, for now. They also take 120 film but there is no standard image size so the options are there for either 6 x 4.5 cm, 6 x 6 cm and 6 x 7 cm with the width of the image being dependent on the camera. The first thing you will notice about the medium format range is how much the quality of the image improves in the finer details.
Large format - producing a negative of 5" x 4", the quality in detail of the large format camera is exceptional especially when blown up. It's basic construction is that of a front plate containing the lens and shutter, then a bellows arrangement to supply the focal length and then a back plate which provides a viewing screen.
Image courtesy of photo tuts
To quote the aforementioned photo tuts " The front and back panels (called ‘standards’) move independently of each other in a series of movements called rise, fall, shift, tilt and swing. This gives the photographer control over converging verticals, the plane of focus and depth of field within the image. Lensbaby products and expensive tilt-shift SLR lenses are attempting to imitate this functionality."
Films are loaded as a single sheet into the camera and even though the standard is 5" x 4" the large format camera has and is being explored in it's capabilities by those producing wet plate work using glass and tin types formats. The photographer sets up the camera prior to the insertion of any film plates and has to firstly cock the shutter to allow light through to the ground glass screen and then, working underneath a suitable dark cloth, they will be able to adjust the compostion, focus, aperture and shutter speed , usually in accordance with a suitable light meter reading and reciprocity table (see below). The film is first loaded onto plates in a changing bag to prevent exposure to light and then once the camera is set up the plate can be slipped into place, the shutter cocked and the protective plate over the front of the film can be slipped out. The shutter is best released via a remote hand held device so as to prevent any camera shake, and then once the picture has been taken the protective plate is reinserted but reversed so as to notify the user that the film has been exposed.
A couple of things of note include, different focal lengths require different lenses, increased bellows length is for shallow depth of field or macro, squashed or compressd bellows are for infinity such as landscapes, portrait mode is achieved by simply rotating the rear.
Below is a 5" x 4" guide to exposure courtesy of jaykayphoto
| 90mm | 150mm | 210mm | Reciprocity | |
| 90 | same | 1 = 1.5 | ||
| 100 | +.25 | 2 = 3 | ||
| 150 | +1.5 | same | 3 = 5 | |
| 200 | +2 | +.75 | same | 4 = 7 |
| 250 | +3 | +1.5 | +.5 | 5 = 9 |
| 300 | +3.5 | +2 | +1 | 6 = 12 |
| 350 | +4 | +2.5 | +1.25 | 7 = 14 |
| 400 | +4.25 | +2.75 | +1.75 | 8 = 17.5 |
| 450 | +4.5 | +3.25 | +2 | 9 = 20 |
| 500 | +5 | +3.5 | +2.25 | 10 = 24 |
| 550 | +5.25 | +3.75 | +2.75 | 11 = 27 |
| 600 | +5.5 | +4 | +3 | 12 = 31 |
| 650 | 5.75 | +4.25 | +3.25 | 13 = 34 |
| 700 | +4.5 | +3.5 | 14 = 38 | |
| 750 | +4.75 | +3.7 | 15 = 45 | |
| 800 | +5 | +3.9 | 16 = 50 | |
| 850 | +4 | 17 = 60 | ||
| 900 | +4.2 | 18 = 69 | ||
| 950 | +4.4 | 19 = 74 | ||
| 1000 | +4.5 | 20 = 85 | ||
| 21 = 91 |
- Measure the bellows of the camera
- Look up the measurement for the appropriate lens on the above scale
- Overexpose by the stops given.
- If the exposure is over 1 second look this up on the reciprocity scale and expose for the given value.
Reciprocity scales vary from film to film with a little more insight into it being available over at Landscape Photography Blog.
Summary
I enjoyed the short time we had with the large format camera in the studio set up and look forward to further adventures to explore it's capabilities but I've come to realise it is a branch of photography that deserves your utmost attention if you are to achieve the desired results, as mistakes can be expensive, but the rewards can be exceptional.
Scanned 5" x 4" lfc neg
Scanned 5" x 4" lfc neg inverted
Basic studio set up
Large format cameras are still used in a lot of studio work because of the quality of image they can produce and are still used in architectural photography for their ability to deal with converging lines. As I final point I've just chosen to include a link that is quite handy for all the necessary formulas and a couple of other pointers over at Ken Rockwell's place.
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