I recently fitted the M25C 6-Megapixel one shot colour CCD to the Canon 200mm prime lens.  Took around an hour to flatten the chip to the lens using CCDInspector, but the time was worth it as I managed to end up with the magic 0.0″ collimation 🙂  As a test shot I went for the Gamma Cassiopeiae region and took 10 x 10-minute subs.  There was a blazing Moon up which didn’t help matters much, but despite the biggest light polluter in the sky wanting to cause problems, the image turned out pretty well in the end.  Processed by Noel Carboni, I find I am falling in love with this lens – it gives me exactly the field of view I’ve always wanted to take since starting out on this game.  So why didn’t I do this long before?  Several reasons really.  I wasn’t overly impressed with DSLR lenses up until now, too much glass and very poor star shapes out at the edges as a rule.  The “too much glass” is also a problem with the 200mm prime as well, you get ghost flares from any bright stars in the FOV, I guess that’s something I just have to live with.  I also didn’t like the fact that you didn’t use all the expensive lens electronics if you stuck a CCD on the back, seemed like a waste of money and technology.  I also couldn’t believe that you could get the performance of a good quality refractor costing anything from 2 to 4 times as much as the lens – wrong again.  I am pretty sure Canon don’t realise what a gem of a lens they have here for astrophotography – just as well really or they would almost certainly bump the price up from the very reasonable £600!

 

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