Hi Chris,
A huge thank you to you for going to so much trouble with all that info and pics. It's helped a lot!
It's all clear and makes sense. Just one question .....
Hubby is pretty keen (if it'll work) to get the 2" Ultra Prime Focus Adaptor on the link I supplied above.
Here it is again. Please click on the pic and it'll come up with more info on it. I was able to copy & Paste info from link so here it is anyway.
It says that it's better than a T-Ring. So will this work for me?
If it will, I'll order it straight away.
2" UltraWide Prime Focus Telescope Adapter
for SLR/DSLR Cameras As seen in "Sky & Telescope" magazine.
http://www.cncsupplyinc.com/mjpt.gifhttp://www.cncsupplyinc.com/t2U-200H.jpg
The True-2 adapter goes directly from Bayonet mount to 2" barrel. Bypassing the restrictive T-Ring.
This increases the clear aperture up to 10mm over conventional T Ring adapters!
http://www.cncsupplyinc.com/T2U-10d-S.jpg
Wider is better! There is zero shading of the CCD sensor.
http://www.cncsupplyinc.com/t2-both-H100.jpg
Available with or without safety Undercut on barrel.
Just say NO to T-Rings!
As the CCD chips in our DSLR cameras get larger it is ever more important to have an unobstructed light path to prevent vignetting. The manufacturers of high end telescopes wisely put 2" eyepiece ports on them. Why then do we insist on putting a 1.5" bottleneck between your camera and telescope?
T-Rings have been around for decades, a legacy standard as outdated as 300 baud modems. They exist not because they are the best solution for imaging, but because they are the best solution for manufacturing. After all it's much easier to spin a standard thread on all adapters, regardless of telescope port size or camera brand. The T-Ring may be convenient but it is simply out of its league on a telescope with a 2" eyepiece port.
True-2™ is a true 2" prime focus telescope adapter that takes you directly from the bayonet mount to a standard 2" barrel with as few wasted photons as is possible, adding as much as 10mm more clear aperture over legacy adapters! The largest clear aperture of any adapter on the market. And it costs little more than you would spend on a T-Ring and a quality 2" T-adapter. Baffled to reduce reflections and threaded for 2" eyepiece filters. Now also available with or without an undercut on the barrel. Don't choke the photons out of your camera with an inferior adapter!