Any ES 52 deg Eyepiece Experience Yet?

[MistrBadgr]

I managed to carry my six inch f/5 reflector through maybe ten inches of snow from my outbuilding, through the house and onto a space I had cleared on my driveway. I viewed the Moon around 9 to 10 PM on Feb 19th. Weather was warmer, I experienced small scale turbulence that was apparent in the Moon's image and i believe there was a bit of high haze or fog. The there had been quite a bit of melting and evaporation of water during the day and some of this was visible as a haze nearer the horizon.

The scope, a Meade LX 86 6R optical tube has a 35% central obstruction, as close as I can measure. I have not done a star test on the optics to my satisfaction yet, but I believe its wave front error to be about one sixth wave as a rough estimate. The mount used is a CG4 with the Celestron 6 volt drive system installed.

The Moon's terminator was running near the Deslandres Walled Plain, which caught my attention. The view, with the ES 52 3mm eyepiece was not completely sharp, as I expected, with this scope, my vision, at its 250X magnification, in the atmospheric conditions. It did, however, provide a reasonable view with good contrast. Looking at the view of this crater on the Virtual Moon Atlas at about 50% of the zoom range, the resolution of my view in the scope was not quite as good as the image in the software, but the distinction in the grey tones in my view was better.

There were some small objects on the crater floor that I could not see at the eyepiece that were visible on the software image and other grey spots that showed up across the upper left portion of the crater floor in my view that were not visible in the software image. I could not tell what these grey spots were, but they were sprinkled all over the area and gave me the impression of rubble. Looking at an image from the Lunar Orbiter, I could see that these spots were small craters of a fairly uniform size, as if the crater floor in that area had been shot with a large shotgun.

I could also see two continuous lines running from near the top of my view of the crater, one almost straight down through the middle of the crater, going maybe 80 % across it. The other veered toward the sun side and traveled maybe half the diameter. My best guess is that these were either rilles or were shadows from long ridges being cast by the low angle of the sun. Neither of these lines were apparent in either the atlas's image or in the image from the Lunar Orbiter.

The eyepiece, in my universe, is excellent. I find no fault with it and believe it will provide the best resolution and grey scaling of lunar views that I will be able to achieve with this scope and my vision. If there are faults in the eyepiece, someone with better optics and vision that mine will have to find it. I consider the purchase of this eyepiece to be a success. I have ordered the 10mm version, as the only one of the remaining lunar/planetary magnifications (4.5, 6.5, and 10mm eyepieces) that are currently available. Eyepieces Etc. had two of them and now have one remaining. I did not find any of them on any other site, though I am confident there are many businesses that I did not check. I have back ordered the 4.5mm and will do the same for the 6.5 at a later date as that money budget pocket fills again. I understand there is no expectation of more of these eyepieces being available until near the end of summer.

Hope this helps someone.

[MistrBadgr]

Correction: I stated that my scope was an LX 86 6R, please read that as LX 85 6R.

Addition: I did not mention anything about the craters that have destroyed much of Deslandres walls and some of the larger secondary craters inside the larger one. Some of those have internal peaks that I could see. I left those out since they were visible in images as well as my view last night and should be visible in much smaller scopes at much lower magnification.

[MistrBadgr]

I have recieved a 10mm ES 52 eyepiece and have had a chance to check it out. It is a nice eyepiece and definitely worth the money. It has very good contrast, in my opinion. The eyepiece is reasonably sharp.

I made a comparison with my Meade 5000 series 9mm Ploessl, which is one of the eyepieces that I really count on for difficult objects. I have used it and taken it with me on business trips so much that the burgundy paint has faded away completely. It and the 14mm in that series that I have are very special. The ES 52-10mm is not quite as sharp as the 9mm by a tiny bit, but is much better when it comes to contrast.

I happened to think about my old KLEE Barlows, both 2.2X and 2.8X, which I bought to use with a DS-2114 that had a primary mirror ground to 425mm fl instead of 450mm and could not come to focus. I had the mirror parabolized and took the booster lens out, with its focuser and put in an Antares helical. This made the scope an f/3.8 Newtonian RFT. I asked myself why I was not using those Barlows, which are corrected for paraboloidal error. The 2.2X is the better Barlow for that service and has a sweet spot at f/4.25. Putting in the 2.2X Barlow with the two eyepieces was a real revelation! The 9mm gave the better resolution, since my eyes were doing well that night, but both gave me a good image of Gassendi Crater.

With that experience, I ordered a GSO Coma Corrector, a recommended 15mm extension piece, and later, a little 1-1/4 inch helical focuser. I may need to order a much thinner extension piece to use with the helical focuser to make it work the way I want it to, similar to the Explore Scientific Coma Corrector. I really wanted one of the ES units, but I could not ignore the roughly $200 difference. I know I will have to do some modifying to get the GSO unit to work the way I want it to, but the difference in money makes it worth the effort.

The sky has not been all that good. Even on the best nights, I have maybe an hour at the most before the sky fogs over at a high level, destroying the transparency. Even with sky deficiencies, and taking them into account, using the ES eyepiece with the Barlow and its coma correction, has been successful and enjoyable.

With some cloudy weather for a day or so yet, I am flocking my older 8 inch f/5 reflector first, doing all the other little tweaks as well, then I will do the 6 inch after that.

I now have a 4.5mm ES 52 and a 5.5mm ES 62 ordered, but they will not be available until late summer. As funds accumulate in my "fun" account, I will order the ES 52 6.5mm. I may order an ES 62 9mm to close the gap between 10mm and 6.5 as much as I can, with eyepieces that have the more modern ES coatings. I might also order the ES 62 14mm to help bridge the gap between the 52 deg 10mm and the 68 degree 16mm in this working set.

The ES 68 eyepieces will also work with the 2.2X KLEE Barlow, but I end up with a ring of fire around the circumference of the field, when there is light enough to see it. The images with these eyepieces were surprisingly sharp with the Barlow. I suspect the ring of fire may have something to do with the coatings ES was using at the time I bought them. I will reserve those for low power use with wider fields of view, rather than using a Barlow for higher power views, most likely.

If ES made 3.3, 3.6, and 4mm eyepieces in either the 52 or 62 degree series, I would certainly buy them, over time, to get smaller steps for lunar and double star viewing with my f/5 scopes, without the use of a Barlow, and only the coma corrector. Other than the magnification gap between the 3 and 4.5mm eyepieces, I am very satisfied with the eyepiece series I can assemble for a wide range of object types.

[MistrBadgr]

I received notice today, April 3rd, that an ES 52 4.5mm eyepiece is being shipped to me. I had one on back order with the expectation that it would not show up until the end of the summer. Apparently, at least some have arrived early.
I immediately placed an ES 52 6.5mm on back order, with the expectation that it will not arrive until the end of the summer. I am using EyepiecesEtc.com.