That's a shame Bytor that the 20mm was a dud , my 14 works very well in my Takahashi SKY90 at f/5 , no problems there and I use my TV Radians 3-12mm in this scope all the time as they are well matched as a unit , again its not embarressed at all .
In my Istar 127mm f/8 frak it's where it really struts its stuff , perfect !
. That's why I say it is as good as my TV Pan's because that's where my Panoptics get most use , an f/8 , 5 inch refractor ,, nice
.
On a side note I have a TV Radian 14mm on the way , just to fill the gap in my Radian collection and I will do a detailed comparo between these two .
As I say the Meade 14mm is a perfect match for the 127mm f/8 Istar , these 2 will be together for as long as I own both ,, a match made in heaven , so they say .
Brian.
Quote:
Originally Posted by bytor666
Hi Brian,
I was able to get out and test the 20mm Meade 5000 waterproof eyepiece a few nights ago. I let my 10" F/4.7 reflector cool down for over an hour with the fan on the back of my scope on full speed. Once I got out in my yard, I lowered the fan to the slowest speed and then I checked out a few open clusters.
Only the central 50% of the field had sharp stars in it. So I thought maybe my scope was not cooled enough, but the temperature was pretty much the same outside as it was on the inside of my house , (where my scope sits when I am not using it), So the scope not being "cooled" enough was ruled out. I also popped in my 14mm ES 100 and stars were sharp all over the field, except maybe the last 5% or so.
...So the bottom line with the new 20mm Meade 5000 waterproof UWA is that it does NOT PLAY WELL with short focal length telescopes. After fiddling about with the focuser I knew exactly what it was: FIELD CURVATURE.
I knew it was that because with field curvature, you can re-focus stars at the edges and the stars in the central FOV became de-focused, and when I focused stars in the central FOV, the outer 50% of stars were defocused. Another thing that miffed me about the 20mm WP UWA was the bothersome eye positioning. I had to leave my eye in one area only or I would get kidney beans.
So, needless to say, I sold the 20mm off the very next day and I won't be missing it one bit. It's a very nice looking eyepiece, but that's where it all ends, LOL. I've owned two Meade 5000 24mm UWA eyepieces, which is NOT the waterproof series, and that one has much better correction all over the field of view. I own the 5.5mm Version of the waterproof series, and that one is excellent across the entire field of view, and it also has really good eye relief.
PS: Brian: How does the 14mm Meade 5000 waterproof work in a fast scope? Have you tried it in a fast reflector like mine?
Cheers,
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