Paul - I have a 1.25" Camera Adaptor that connects to the "T" ring - and slides into the focuser (like an eye-piece). Bintel Camera Adapter 1.25"
https://www.bintelshop.com.au/Product.aspx?ID=6384
Your comments about an optimal distance from the last element of the focal reducer to the image surface is a concern for me. I will have measure my setup to see how long it actually is. I think that my setup may be a bit too "long". Do you know what the optimal distance should be? You mentioned 105mm - is this an exact distance or is there a preferred range?? Are there any written references that you are aware of?
What about a 1.25" adaptor compared to a 2" adaptor - Does this makes any difference? Does anyone else use a 1.25" adaptor and a 350d?
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Thanks for the positive comments Dr Nick - I still feel I have a long way to go. Practice, Practice, Practice...