To cure these problems, the lens was dismantled, its front and rear surfaces were repolished, the other surfaces were cleaned, then all surfaces were coated – a degree of lens 'surgery' that was not uncommon at a time when severe post-war British import controls made it impossible for amateurs to buy new Leitz equipment. Total cost of this work was six pounds sterling (around $18 at 1956 exchange rates) - the equivalent of around 160 pounds ($220) at today's prices.
Having established the basic technique of digitising with a BEOON-mounted camera, I was ready to try a small number of colour negatives taken during my holidays in Greece during the mid-1980s. Like most colour negatives, these contain an orange layer intended to overcome imperfections in the cyan, magenta, and yellow dyes. The software used to drive film scanners is designed to cope with colour negatives, and will apply a correction intended to remove the effects of the orange layer, so an equivalent to this process must be done to images taken with colour negatives using the BEOON or a similar copying stand. Several companies offer software custom-designed for this task, but acceptable results can be obtained using Camera Raw and Photoshop.
After my first attempt at using the BEOON-mounted M9-P to photograph a colour negative, I was surprised to find that the captured image showed no significant colour cast. Part of the space between individual frames was visible, and this clear space showed only a faint grey colour, with no hint of orange. The camera's white balance had been set to 'Auto', so its firmware had presumably interpreted the orange layer as the result of some form of ghastly lighting condition and had attempted a suitable correction.
Since the Camera Raw plug-in needed to import DNG files into Photoshop offers 'Auto' and 'As shot' options for white balance, I use its 'Auto' setting to make a similar correction rather than relying on the camera's white balance options. As a result, the task of rebalancing the image is given to software running under the full processing power of a desktop computer, rather than leaving it to the firmware and limited processing capabilities of the camera. Subsequent experiments have confirmed that imports made using Camera Raw's 'Auto' setting produce a better final image that samples made with the camera's 'Auto' selection followed by an 'As shot' import via Camera Raw.
To obtain the most accurate image of colour negatives, the camera has to be adjusted to the optimum white balance. This can be done by setting its white balance to 'Manual', then photographing the illuminated screen of the light panel. The camera should be set to produce DNG files – you can use JPEG, but there may be a minor loss of quality in the final result.
Once colour negatives had been photographed using this white balance setting, then passed to Camera RAW with the latter is set to 'Auto', the image will be rebalanced, a process that greatly reduces the orange tint. Cropping can be used to remove any non-image parts of the frame, so that the automatic processes which follow are based entirely on the image.
Directly underneath the photo, Camera RAW will indicate the bit size of the planned export to Photoshop. If it indicates 8-bit, clicking on the blue text will allow 16-bit to be selected. In order to convert the colour negative into a colour positive, the individual pixels are going to be remapped, so working at the 16-bit level will allow this process to be done with greater precision.
Clicking on Camera Raw's 'Open image' button will transfer the rebalanced image to Photoshop. Th e procedures that follow are for Photoshop CS6, so users of other software will have to 'translate' these it in order to match the interface and commands of their program.
'Select Image => Adjustments => Invert' will convert the image to a positive, but this is likely to be of low contrast and limited colour saturation. The simplest method of creating a balanced full-colour image is to use 'Select Image => Auto Color'. If the result is not satisfactory, 'Edit => Undo' can used to cancel the operation, followed by 'Select Image => Auto Tone'.
If neither of these automated processes gives a good result, the final option is to revert to the inverted image, then select Photoshop's 'Images => Adjustments => Levels', and adjust the white and black points for the red, blue, and green channels in turn.
Whichever of these methods proves best for an individual photograph, 'Select Image => Adjustments => Hue/Saturation' will then allow you to explore the effects of slight changes in the master settings of Hue and Saturation should these prove necessary. Small changes in hue might be useful in photos that include neutral tones or flesh tones. Once the end result is satisfactory, selecting 'Image => Mode => 8bit' allows the photograph to be stored in whatever format seems best.
Digitising with the camera is faster than scanning but as in the days of the traditional darkroom, dust is the enemy. My approach is to use the Photoshop healing brush to edit out the most obvious flaws, and only tackle the minor ones at leisure or when the photo is needed for use.