daodang said:
Bjorn,
Beautiful abstract image. I'm ver interested to experiment on shallow DOF photography too. Could you please give more details about how and where to get those lenses CPU modified. Thanks in advance.
Regards.
These lenses can be found any place where hospitals upgrade their X-ray equipment, at e-Bay, surplus medical stores, etc. etc. you name it. In other words, not really hard to find if you snoop around a litlle off the main road.
This particular lens has a story to go with it. Some months ago I visited a friend of mine in Bergen, west Norway, and showed him some of my Heligons. He then remembered that he had himself an acquitance who worked at the X-ray department of the local hospital, and during our conversation he got a little excited about asking this guy whether he had access to any such lens. Soon thereafter he called him and was told "sure, plenty, just come over and have a look". We knocked on the guy's door in 5 minutes flat, and were shown a floor-to-ceiling bookshelf
filled to the brim with surplus X-ray lenses. He had so many he said
we could just pick some samples for free, which we did promptly. That night we returned with a bag full of X-ray goodies, amongst them four absolutely perfect 50 mm f/0.75 lenses. Most of the 42/50 mm lenses I've used so far have had severe element separation due to radioactive contamination, but these lenses were pristine and pure joy to behold.
As to the CPU-modification, that's not really so difficult. I mostly mount a 52 mm male-thread adapter (Cokin) on the rear of the lens by means of 3 flat-headed screws, and add a K2 adapter plus possibly a K4 (or a 52 mm filter with the glass removed) to get the spacing right. Usually there is plenty of room here to drill the needed mounting holes in the K2 bayonet, and fit the CPU print from a 45/2.8 AI-P Nikkor. However ,with the emergence of D2X (and D2H), I consider this practice no longer necessary unless I want to use the lens on a D70 or suchlike body.