Can anyone tell me how well the 120ST works with the aperature stopped down? I was told the lens cap has a 55 mm aperature stop to run it at F11. I was thinking of getting the 120ST, using the 55 mm aperature stop and a V-filter to reduce the chromatic aberration. I plan to run a 5.1 mm ED eyepiece at X118. Does this sound like a plan for the moon and planets?
Orion Astroview 120ST
Started by dcuthbert, 06/07/2005 01:15PM
Posted 06/07/2005 01:15PM
Opening Post
Posted 06/07/2005 05:13PM
#1
The focal length of the 120ST is 600mm. First step here is to get a Minus Violet filter, clean things up a bit. Then try various aperture masks until you find one that you like, just cut them out of cardboard.
My own guess would be that you might like something between 80 and 100mm, 80mm would be F7.5 and 100mm F6. My own preference between an 80mm F11 and a 100mm F6 is for the 100mm...
Also, I have generally heard bad things about the ED-2, Celestron Excel eyepieces, I had the 5mm and gave it away as i was not comfortable selling it....
jon
My own guess would be that you might like something between 80 and 100mm, 80mm would be F7.5 and 100mm F6. My own preference between an 80mm F11 and a 100mm F6 is for the 100mm...
Also, I have generally heard bad things about the ED-2, Celestron Excel eyepieces, I had the 5mm and gave it away as i was not comfortable selling it....
jon
Funding Member
