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Allright - did some experimenting only last night amongst the clouds, but was able to watch a fair bit of the Rugby and Le Tour.
The bracket itself works fine and the focusing motor worked well. I didn't get around to trying a focusmax run, but after watching the size of stars change as I manually focused, I have no reason to think it won't work.
Here is the summary of what I discovered about the 14-24mm lens.
Zoom lenses are incredibly sensitive to backfocus distance. The QSI and it's dedicated adaptor are advertised as providing the correct backfocus distance for a Nikon lens. However, when you put a 3mm astrodon filter into the optical path, it effectively shortens the backfocus by 1mm. This creates major problems. At 14mm the lens would focus, but the distance scale on the side of the lens was reading ~0.35m??? The distortion at the periphery of the field was pretty shocking too - unusable.
So, I tried an empty filter slot and it focused at the infinity marker - much better. I guess the complex optics are designed for a certain back focus and deviating from the distance is not allowed! Next, I'll try to get a 1mm thick piece of aluminium cut (hopefully OzStockman can oblige with his laser) as a spacer - for those with a QSI, I think I should be able to get it to go between the T-mount faceplate and the WS cover.
So how did it go without a filter - at 14mm there is a fair bit of distortion/coma at the periphery, but at 24mm the image is definitely usable. I ran the 24mm image through CCD inspector and it gave ~12% curvature. I only shot a couple of frames amongst the clouds. I'll post some links to them - JPEGS, cloudy, light pollution, but they'll give you the idea.
All in all, I think I will have much more success and less frustration with prime lenses, but was curious to see what the 14-24 could produce.
DT
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