The two big problems that arise are how do you get close enough to take a meaningful picture and how do you know that it is going to be in focus? For the first, essentially all you need to do is find a magnifying glass that will get your eyes to about the magnification that you are hoping to get - and then figure out a way of attaching it to the front of your Holga. In my case the answer was a linen tester, one of those natty little folding magnifiers, it is slightly too small but unless you know that you wouldn't notice in the pictures. Attachment was a very technical affair, consisting of two small squares of masking tape - the professional photographer's solution to fixing anything - unless its weight requires Gaffa tape.
So now I have a functioning closeup camera capable of focussing - close... just how close though was a mystery. In order to see how close I could have resorted to mathematics, or trial and error but I suspect that I would have given up long before I had worked it out either way. No, what I needed was a focussing screen. Holga, in their wisdom actually supply the main component of the focussing screen with the 120 camera, they supply a 6x6 mask and a 6x4.5 mask. The application of a sheet of tracing paper to the back of the spare frame completes the screen. Fitting it and opening the shutter on 'B' gives you a dim but useable view of the scene and you are ready to get measuring.
I am not going to pretend that this is an accurate closeup camera but for a Holga enthusiast this will not be either news - or a problem, it is the essence of the challenge and great fun.
The linen tester gave me a focus point at about 3cm in front of the lens. It was a good job that my intention was 'arty' rather than super sharp, at these sort of distances a movement of a couple of millimeters equates to sharp or soft, however sharp was not the plan so I thought I'd just have a go and see what I got.
I did use a tripod, exposures metered at about half a second which I did by guesswork on 'B' setting. I shot off a roll of Lucky 100 120 and processed it as I did last time, using my fleece changing bag and one of the resulting pictures is above. I did clean the pictures in Photoshop, the inevitable scratches did nothing for this subject but otherwise they are pretty much as scanned.
This Polaroid shows the linen tester taped to the camera and also the focussing screen.
There are 4 other pictures in the Gallery at www.minutefilm.co.uk along with other pictures, both Polaroid and Holga.
They are also on my Facebook pages