This idea of using the downlight/spotlight things is great and I/m now thinking of a high-power version of a Varicon head.
However, I'm wondering about the distance from the condenser (via the mirror) -- shouldn't the illuminated surface be on the former centreline of the bulb, in order to be concentrated optimally by the condenser(s) ? With any luck there is so much light power available that this isn't a problem, but it might make a difference at extremes.
I'm also curious about the turn-on delay of the unit. Does the enlarger keep the bulb on all the time and have a shutter for exposures?
Re the turn on delay, yes there is a fraction of a second delay but much less than dry down effect so not something I agonise over! It is not unusual for variations in the mains supply to visibly change the light output from the bulb in any case, so I think the output from a 12v source may in fact be more consistent. I make a small adjustment to my starting exposure on the first print based on the number of exposures on the test strip but I think this is immaterial given my final print is usually version 4 or 5 after time and contrast adjustment, dodge, burn etc etc.
There is no shutter. Light goes on and off via an RH timer in my case.
Last edited by Tony Egan; 04-03-2013 at 04:49 PM. Click to view previous post history.
Reason: Addnl info