Post by Chicago Astronomer - Astro Joe on Jan 10, 2011 13:13:47 GMT -6
A Meade and Russell Optics 2" 56mm Eyepiece Shootout
The Chicago Astronomer has two 56mm 2" eyepieces in his arsenal. It didn't start out this way, but that's how it worked out.
I desired a low powered eyepiece for sweeping vistas and wide FOVs. High power is very cool, especially with the C11, but there are times when the whole is just as good as a magnified section of a celestial object.
I debated greatly on which eyepiece to get -
( astronomer.proboards.com/index.cgi?board=Equipment&action=display&thread=2979 )
... and narrowed it down to the Russel Optics 56mm and the Meade 56mm. Comparable in price...I went with the Russel...
It arrived soon enough and I also bought the Russel Focal reducer...
...of which Russell wrote me back, stating that he would combine both into one shipment and saved me some bucks. Very cool of him... ;D
It's been cold...very cold in Chicago of recent and I have not been able to try it out. But on a bitter cold night, I tried it out and it performed...ok. But with reservations.
Granted that it was just a cursory quick and dirty view through the C5, (too cold to handle the C11), but I expected more. It arrived as just the eyepiece - no case nor eye cups. The eye relief is awkward - with such a long mm, one has to stand back from the eyepiece some, forcing one to cup one's hands around the eyepiece to block out the stray light. perhaps this is suitable for dark sky country, but for urban astronomy...a hassle.
Unsure what to make of it, I needed to to compare it with another 56mm - and since I know no one with one...I then ordered the Meade...
It's a hefty eyepiece.
The eyepiece case arrived damaged, with the bottom cracked out. Not worth complaining about and some crazy glue solves many of life's problems.
But let's compare the dimensions of the two before we take them out....
The Meade of the left, the Celestron 40mm on the right and the Russell in front.
The Russell is a little more than 70mm, (3.25"), in height...
The Meade is gigantic in comparison...
It measures 115mm in height, (5"), and is very hefty.
The user side of the eyepiece measures at 25mm, (1.)
..and the Russell at 40mm, (1.50')
Both ends are of equal dimensions. One would think that the larger exit aperture of the Russell would be superior, but wait, I was surprised at the field testing.
The Russell comes in two pieces..
The five element optics appear to be coated and pretty much flat.
The Meade comes in three pieces...
Including the sleeve barrel, (not shown detached).
The user end, without the top case ring, measures close to 50mm
Now, why is this closed down to 25mm....? The quick field test provided some answers. (Wait...it's coming.)
A selling point of the Meade was about the "Blackened" edge of the optics, cutting down glare and improving contrast...
Perhaps so, but it just looks like someone ran a black marker along the edge...
I think I will improve on this when it gets warmer, darkening the edges with proper coverage. It's a four (4) element eyepiece, this Meade...
The optics also appear to be coated, but there's more of a curve to the optics here than the Russell. And putting it back together, I noticed that the top case ring kept the user away from the front surface of the eyepiece at about 1 inch...
With all of the eyepieces back together...
It was time to take them out into the bitter cold and see what they deliver. Anxious to try it out, of course it was cloudy for several days, (sorry), but Sunday evening, (9th of January), it finally was warm and semi clear enough to compare the two - but again on the C5.
Setting outside of my garage, I also used the 40mm Celestron as a baseline to start from...
The Moon was in a very nice conjunction with Jupiter, riding high, but I will focus on the Moon for this preliminary field test.
I popped in the Russell first...
Indeed, the view was wider, making a small Moon fill about 75% of the FOV. But, the eye relief was troublesome. One does not place the eye next to the eyepiece here, but instead, keeps a distance of about one inch away- then the view is good.
But it's difficult to keep this distance constant - with the view "blackening" out when passing the optimum distance - both in & out. And the ambient light of city life is a great intrusion, forcing one to cup both hands over the eyepiece in an attempt to isolate the view from the surrounding environment. Apart from this, the views were crisp and craters razor sharp. Although, I was disappointed with the apparent degree of the FOV, (50 degrees +/- ) - as I was with the Meade. The Celestron 40mm is a much more comfortable open "porthole" experience than either of the two 56mms.
Slipping in the Meade, the view was more comfortable. Now, I understand why Meade keeps the user an inch away from the front surface of the eyepiece. It avoids the troublesome eye relief that the Russell exhibits. With the upper ring & eyecup on the Meade, the user maintains the proper distance and does not experience the "sweet spot" search.
The view of the Moon was just slightly larger than the Russell, but with a similar degree in FOV. Clear, but not as crisp as the Russell.
Using the 40mm as a comparison, the Moon now, loomed large in the FOV, taking up a large percent of the FOV Popping in the Russell, the Moon shrank to an orb floating in space.
Well...ok...
Slewing to the Beehive cluster in Cancer, this would enable some quick comparison of FOV and edge to edge performance.
Starting out with the 40mm already in place, the cluster was nice and pretty much filling in the FOV...just barely. The Meade fit the cluster in comfortably, sharp in the center, but some coma near the edges. But the Russell was clear and sharp from practically edge-to-edge. With just slightly less magnification than the Meade, it made for a nice stepped back view of the cluster.
Preliminary summary...
The Meade:
- is more comfortable to use
- bulkier and heavier
- came with eyepiece cup and holder case
The Russell:
- Sharper edge-to-edge
- hard to find the "Sweet Spot"
- no eyepiece cup or holder
Over all...
In this cursory quick shoot out...they both are good. I just may work on the Russell to bring the sweet spot into a set distance with some sort of extended tubing and eyecup. I wish either one would have a better wider FOV, (52 degrees +/- ), but for the price, I can't complain. But, it harkens back to using 1.25" eyepieces...sorta.
(I used the Focal Reducer as well, but it'll muck up the evaluation now, and for another post. soon.)
Both eyepieces share a similar real FOV, even with the closed down aperture on the user side of the Meade at 25mm. When one holds up both eyepieces to both eyes at the usable distance, the FOV appear to be the same very closely. I am curious to remove the upper ring on the Meade4 and see if it exhibits the sames "blackening out" as the Russell does, when not in the optimum distance. I suspect that it will.
A more careful evaluation will be performed when it gets warmer, but I like them both and perhaps will use the Russell for astrophotography and the Meade for visual - especially at star parties. I'm anxious to try these out on the C11 and see how they compliment the scope.
It's always good to have two of everything - binary you know.
(But, that low line 40mm Celestron held up it's own!)
