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Hi Philip
Top effort!!
Keep up the good work and with the knowledge that I am impart to you it can only get better.
While a Hartman Mask is a good idea there is a cheap and easier method than this and that is to use diffraction spicks. The method works like this, place two pieces of string on the front of the OTA so that it forms a cross (much like the cross hair in your finderscope). Next you need to take an image and examine the diffraction spicks around a bright star if you see six spicks (2 above the star, 2 below and 2 to the left and right) you have not achieve focus. Continue to image and adjust the focus until you have one single spick (1 above the star, 1 below and 1 to the left and right) at this point you have achieve perfect focus.
To use the above method I would recommend that you control your camera via a laptop and use the supplied Canon “Digital Photo Professional” software. You can take exposure up 30sec and down load directly to the computer to be examined. I also highly recommend DSLRFocus by Chris Venter if you wish to take images longer than 30sec and also it has a nice little routine for achieving critical focus. If you would like I can also help you out with the long exposure serial cable (you can contact me on my private e-mail.)
I have also included an image of the Orion Nebula that I took on my first night out with my new 350D. The image was take through an ED80 piggyback a top an LX200, unguided. Processed with Registax and Photoshop.
Anthony
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