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8x10 Camera Build: Working Prototype

Since the last post I have been busy in the workshop with the arrival of the ironmongery to assemble the wooden parts of a 8x10 camera I started building last summer. Over the last four days have made a working prototype, brass rack and spur gears fitted, aluminium machined and stainless steel knurled nuts have been attached to the camera's movements. It is always nice to see the pile of wooden components fitted together and one can start to get a sense if the concept will work or not. The camera shown in the photographs has been modified and hacked about from what I originally intended to build last summer. It is a bit crude at the moment and further work is required refining and shaping the form but the intent was to see if it work, if it is fit for purpose before making it a thing of beauty which will happen further down the line as a wooden 8x10 should be a thing of beauty.

8x10 Camera Build: Copal No 1 and No 3

I have been playing around with the front standard and lens mount, the front standard was originally to have vertical rise and lateral movements, tilt and rotation but I have decided from experience over the past year doing large format landscape photography that I will limit the movement just to a vertical rise. Occasionally I might employ tilt to get a great depth of field if the foreground is dominate but otherwise the vertical rise is the most and only used movement I use for the sort of landscape photography I do which is referred to as 'the straight photograph'. The slots on the uprights that allow the lens board to moved up and down is a bit too long for this new design as it was originally designed to have an additional turn knob for the tilt mechanism, a new standard will be made at a later date if it is decided I can live without the tilt movement which can be useful in retaining a greater depth of field whilst using larger aperture to increase the shutter speed on windy days.

A Sinar lens board adapter will be used that can accept Linhof style lens boards so a variety of lens and lens boards can be used and tested on the camera. At the School of the Arts [Loughborough University] we use a Schneider Apo-Symmar 300mm lens on our Toyo 8x10 metal technical field camera and a Nikon W 300mm [Sinar lens board] on our 8x10 Tachara wooden field camera , these lens are beautiful pieces of glass suitable for all forms of photography from still life, portraiture and landscape but they are big and heavy pieces of glass. For this lightweight fixed back 8x10 camera I have been looking at alternatives and realised I can use my Schneider 210mm lens which is mounted on a Linhof lens board. I have done a couple of focal length tests with the Schneider 210mm lens on the School's technical 8x10 camera and roughly measuring the distance between the front and rear standards infinity requires an extension of 150mm and to focus on a object just 45cm from the lens requires an extension of 300mm, both extensions are well within the movements of the new build camera. Looking at different forums the Schneider 210mm on an 8x10 camera will exhibit no vignetting at f22 and below which should be fine for landscape photography, if a narrow depth of field is required using a wide aperture any vignetting should be slight and treated as part of the aesthetic. Further research has brought the Nikon M large format lens series to my attention, their 300mm and 450mm lens are small and light making them ideal for landscape photography, they are no bigger than a Schneider 210 mm lens and use the same Copal No 1 shutter, the Nikon M lenses may not have the finesse of the bigger Schneider 300mm lens but the Nikon M 300mm should be ideal for this camera and the Nikon M 450mm at f22 has an large enough circle coverage without vignetting for the 8x20 camera I will be making over the coming year. I have done some quick tests to see what the maximum extension required for a 300mm lens on the School's technical 8x10 camera and for infinity it was 220mm extension and to focus on an object about one meter from the lens a 320mm extension was required, both of theses these extensions are well within the movements of the fixed back 8x10 camera without putting the chassis under undue stress, pushed to the limit the camera can extend to 400mm between the front and rear standards.

8x10 Camera Build: Extended [350mm between rear and front standard]

The brass MOD 0.8 rack and spur gear works a dream and is a lot more smother than the steal version I used on the 20x24 camera, it was an expensive option but in my view worth the additional cost. A 4mm diameter stainless steel rod was used to connect the spur gears which required the sourcing of thread reducers for the larger M6 knurled nuts which focus the camera, M4 knurled nuts only come with a diameter of 16mm, too small for a focusing knob, the larger M6 knurled nut with a diameter of about 22mm feel just right in the hand when focusing, M4 knurled nuts are used on the left hand side of the camera to lock the camera extension movements. If I was designing the movements of the 8x10 camera chassis again and with the 8x20 camera in mind I would go for 6mm diameter rod, there is not much difference in weight and it mean less play in the movement, machining and adapting the knurled nuts.

8x10 Camera Build: View of rear of camera

8x10 Camera Build: Removing the ground glass

8x10 Camera Build: Inserting a dark slide

8x10 Camera Build: Rear Standard