Quote:
Originally Posted by Vanda
I'm impressed Rob. this was a piggyback with a 55mm lens? Not sure as you mention a barlow. ISO 400? 3 min? F stop? Noise reduction on?
Looks great!
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Thanks Ian. Yes, it was piggybacked - the Barlow was on the reticle to give increased scale as the scope is a short fl - 80mm f5. Only did short exposures while I got the feel of using the reticle - Canon 400D, 55mm in 55-200mm zoom lens, 7 x 30 sec, ISO 1600, F/4, ICNR on. My feeling is (given that my mount is very flimsy) that the shorter time you expose for, the less the chance of something going wrong. Hence lower ISOs are out. Even out the noise with lots of subs.
If you have a solid mount and an RA drive, by all means drop your ISO back as you'll be able to go a long time, just making corrections with the slo-mo knobs. Once I start, I have to maintain an extremely controlled, even pressure on the knob because like it or not I've exerted flex on the mount. If I stop that pressure for any reason, the star flies away, same if I start again. But really it's pretty easy - lots of people used to do it this way once!
Link to a higher res image (actual pixel size) of the Southern Cross/Coal sack here:
http://i727.photobucket.com/albums/w...ghirescrop.jpg
Attached is a pic of my imaging set-up as it stands.
Cheers -