Hello!
What with all this locking down business and home schooling my ten year old son, I have dusted off my TAL-1 and created a slightly less than ideal setup in his room. The westward facing window has been providing great views of the moon and venus over the past week. Obviously doing this indoors is not great (the floor is pretty solid, as is the TAL stand!) but it does mean we get to use the scope every evening, rather than going through the process of carrying the whole rig outside every day.
I have a T-mount converter for my old-ish Pentax k-M DSLR, but have quite disappointing results with the camera, when compared to the observed image using the eye. The eyeball view is nothing less than banging - crystal clear detail with a 25mm eyepiece, strong contrast - it's spectacular. I add the camera with an eyepiece inside a tube, and can't replicate the same result, or anything like it. It's OK, but not good enough.
I've cleaned the eyepiece today and collimated the scope. The primary mirror looks fine other than a couple of tiny dust particles, no scratches or weirdness on the coating. The camera is working pretty well as far as I can tell. Apart from a little clumsy-ness with the adjustments, the clarity in the eyepiece suggests it's all working fairly well. Photo attached of best result from last night.
My question is: is this a focusing issue or some sort of aberration? Should I expect focusing to be difficult in the camera eyepiece? What's going on?! Does anyone have any other tips I can try to get this working better?