View Full Version here: : ED-2 2.3mm
08-03-2007, 12:39 AM
I just got one of these things the other day. I will write a review of sorts when I get the time. I share with you the following.
You need a wide angle lens to view it up close:)
It is 13 cm long (just under 5.5") and 4.4cm across (1 3/4").
It dwarfs my other plossels, but weighs about the same as my 9.7mm meade with barlow, and less than the 25mm plossel with barlow.
The seeing was truly horrid tonight and planets move like the wind but the views were really quite promising. Could Saturn look that big?
I look forward to testing it a lot.
08-03-2007, 12:48 AM
Col, at 2.3mm you are going to need excellent seeing! Good luck with it. Must give nice close-ups when the seeing permits. I look forward to your review.
08-03-2007, 05:44 AM
A 2.3mm eyepiece in a 4.5" scope? I reckon that's probably pushing it a bit far, and as Ken says, will only be useful in excellent seeing (very few nights of the year).
But when it is good, watch out! Look forward to hearing more of your thoughts.
08-03-2007, 01:35 PM
Quite right great ones!:) I plan to use it in a much wider scope...
I could not resist getting one now (all of $59) and trying it out. Honestly if the tracking was not so beastly on the mount I have it would be much better. I look forward to cold winter nights.
11-03-2007, 02:52 AM
More fun last night with the ED-2. Much cooler (20 degrees) and better seeing. Saturn lacked contrast but was still very bright - but the mount proved too wobbly - particularly with a strong Easterly breeze - to keep it on for long. I gave up and tried the moon. This time I just zeroed in, focussed and let the moon drift across. Pointing into the wind was much better. Definitely some boiling on the edges of the moon and intermittently on the surface. The seeing was really not quite up to it :D, and no doubt there was that kidney bean effect. As somebody else said - took about 30 seconds to get used to it. I pulled up and old chair and sat on the back and relaxed. Occasionally anoying floaters or other debris would swim in and out of view. The main thing is too ignore them and they go away. The terminator was fantastic and the individual craters were amazing. I will try it out again later on Jupiter and Mars. Meanwhile the edges do not seem to blur or go out of focus which is nice (but the tube is F8). Gosh if I had a telescope that could track properly without acting like a windvane!...That new scope cannot come soon enough!
More to follow...
18-03-2007, 03:43 AM
So you are probably wondering what this eyepiece is for. Well if my maths do not deceive me at 2.3 mm to get a bare minimum 0.5mm exit pupil needs a F4.6 scope. So it is for short tube reflectors. At that focal ratio it provides about 51 power per inch. So it is a high power planetary eyepiece with good eye relief (20mm) obviously overpowered in my f8 scope but still fun I wonder what it would be like in the f4 short tube 8 " GS 600 reflectors at Andrews...
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