Has anyone tried one of these? It's called a Focoblitz, and runs off the mains. The sensor is placed on the easel, and the B/W cathode ray screen displays the grain, sharp as a tack, when in focus. No peering into an eye-piece whilst stretching the right arm up to turn the focus knob. And when I tested it against a large and small Paterson grain focusser, and compared the discernible grain on the equivalent of a 20x16" enlargement from 35mm, the indicated focus from the Focoblitz gave the sharpest grain.
Of course there are downsides. There is expense - I paid over £100 on eBay a couple of years ago (they are £1000 odd new if still obtainable; I'm not sure what the original use was, but doubt it was photography). And the the screen gives out light though it reduces to very little if a cap is place over the sensor. When switched off there is that residual CRT glow, so it is not very practical if you hand-focus every time you move the enlarger head.
So why did I buy it? Because I love autofocus, having a Focomat V35, where the autofocus is spot on. Then I bought an old Durst DA900 for medium format, supposedly autofocus too; but it was all out of kilter. I went potty trying to fine tune it, by adjusting the cam and any other variable; and the tuning involves accurate focussing at top and bottom of the enlarger column; leading to stiff neck and aching shoulder, on top of which, as noted here, it is not always that easy to see the grain.
So this machine was a godsend; now the tuning is done, autofocus is as accurate as the V35. Now I just check focus at the beginning of a session, turn the machine off and the screen to the wall, and I am away. In fact the autofocus has been so good for so long I only check occasionally, but if ever it goes off I will be able to re-adjust it.
Richard
PS It was expensive, if not a lot more than a Peak; but the kids have all left home and they have all got paid jobs, so I thought I would give myself a little treat
