mrngbss wrote:Is 18 min enough to do imaging? Tachyon?
Generally, it takes about 1 min to slew to the object, and 3-5 mins to center the object and set the autoguider. First timers may take up to 10 mins.
After that, the exposure times will depend on the object to be imaged. If it is a brighter DSO object like M42, then 30s x 4 each for L, R, G & B should be sufficient, giving a total of 8 mins exposure time. Including filter changing time of about 15s each, that should work out to 9-10 min each.
The total time at the scope would be about 15 mins each.
However, for dimmer DSOs, you may need 1-5 mins of exposure each, and I once did a 60-min session for just one object, and that was just the minimum!
If you have only 18 mins, I suggest to stick to brighter objects like planets and brighter DSOs.
Cheers!
[80% Steve, 20% Alfred] ------- Probability of Clear Skies = (Age of newest equipment in days) / [(Number of observers) * (Total Aperture of all telescopes present in mm)]