Louis D

Sorry, but not enough eye relief to interest me. Besides, I have 9mm Morpheus, 7mm XW, and 5.2mm XL at approximately those focal lengths, so I'm good. I also have a S-W 5-8mm zoom if I want to go wider with less eye relief in that focal length range. There has been little forum reporting on these eyepieces that I've seen. The initial 2019 lot had to be recalled due to image quality issues (reversed lens maybe?). This was fixed by year end 2020, perhaps earlier. Denis the binoviewer guru posted a brief reaction to his 8.5mm pair on CN.

The LER lineup within the 82 series (4.5/6.5/8.5mm) are new designs to increase the eye relief a bit compared to their predecessors. They came onto the market over 2 years ago. It appears that the old 4.7/6.7/8.8mm 82s are now discontinued to make room for these new LER eyepieces.

It all depends on the relative humidity inside and outside, and if you're using a watertight case (which an IP65 apparently is). For instance, in the winter, our outside air in Texas is bone dry most of the time, while the air inside my house is rather moist. Thus, I cap and pack my eyepieces into my Doskocil watertight cases before going inside to prevent dewing and simply store them away. I typically cap my OTAs before bringing them inside to slow the otherwise instantaneous dewing, allowing them to warm up with the trapped, dry air inside them. Once warmed, I remove the covers just to be safe and wait to put them away. However, in the summer when it's a hot swamp outside and relatively dry and cool inside my house thanks to AC, I bring everything inside uncapped and let it all cool down and dry out before packing it away.

Merging high power eyepiece views can be problematic because they can expose any slight collimation issues in the binoviewer. I do as Jeremy suggests above, use low power eyepieces with a Barlow element out front of the BV. Since I end up operating at 3x or about f/18, just about any wide field eyepiece looks great.

What sort of chair do you use while observing with this setup?

Would definitely melt here in our summer heat. It got up to 102° F here yesterday.

Contrast seems to go way down at higher powers without increasing aperture. That's one reason going with a large Dob with a very well figured mirror can reveal lots of additional planetary detail. Of course, steady seeing conditions as we have most of the summer here in Texas really help as well.

I didn't realize it was possible to screw the Barlow into the lens assembly rather than the 1.25" filter threads. That must be where so much of the confusion arises with this combination. Have you tried screwing the Barlow into the 1.25" filter threads in 1.25" mode to avoid the rotation issues you experienced screwing it into the lens assembly?

So, the 1.25" barrel rotates as the BHZ is zoomed? I knew the upper barrel holding the eye cup rotates, but I was unaware of this secondary rotation.

I tried a pair of 17mm Astro Tech AF70 which are optically the same as the SW SWA 70s. I couldn't get my nose between the two because the tops are too broad, too close to the eye lens. I need a tapered top or a narrow body overall. I find a 60 to 65 degree eyepiece pair is fine for binoviewing because you can't look off axis without losing the view through one or the other eyepiece. With two eyes, it seems at least 5 degrees wider than with monovision. Have you considered using a ~20mm eyepiece with a 2x Barlow nosepiece to get upwards of a 7mm equivalent (2x operating a ~3x due to optical path length). At the higher f-ratio, just about any 20mm looks great.

For the same money, keep an eye out for a used Celestron Ultima, Parks Gold Series or Orion Shorty Plus 2x Barlow. They are still one of the best shorties I've ever used.

If it gives an orthoscopic view (ie., without magnification distortion across the field), then the term orthoscopic can certainly be applied. An Abbe orthoscopic is simply one design that gets you there. As far as I know, these Starbase orthos have never claimed to be Abbe orthoscopics. However, there are reports that the Starbase orthos actually have some distortion which would then call into question labeling them as orthoscopic.

The volcano topped ones tend to steer eyelashes away from the tiny lens. That, and you are much more aware of how close you are, so you tend to be more aware of blinking and pull away first knowing what a pain they are to clean.

I have the 90mm version and enjoy the views through it quite a bit. In focus, I don't see any false color. Star images are nice and tight. The focuser is very hefty, though a bit spongy at high loads in that the fine focus tends to require overshoot when trying to raise the tube. I really like the camera angle adapter on the end of it to rotate the diagonal safely while heavily loaded without having to disturb the angle of the focus knobs. All that said, it's not really a high power grab and go scope. It takes at least 30 minutes to acclimate that hefty triplet. Until then, bright stars are crazy spiky as if the optics are pinched. Thus, you have to be content with low power views until thermal equilibrium is achieved. As such, I might consider an FPL-53 or fluorite doublet next time.

Except on the 27mm Panoptic which has a broad top and an exposed metal retaining ring around the eye lens. I pushed in too hard years ago with a pair of glasses to try to take in the entire FOV at once and put a permanent arc shaped scratch on them. Needless to say, I never did that again.

If you needed the eye cup all the way down as I do to take in the view, then you would be using all of the available eye relief. You, on the other hand, could get away with using eyepieces having 10mm to 12mm of eye relief quite easily, calculated from 20mm minus the amount the eye cup is twisted up. I, wearing eyeglasses with such an eyepiece, would only see the inner part of the field. Thus, I would be using more eye relief than is available. Preferring to nestle into the eye cup is simply a preference and can be arrived at with shorter eye relief eyepieces if the eye cup isn't twisted upward as much or at all.

Quite the opposite. You tend to use very little of the available eye relief; so as a result, you wind the eye cup to the top to eliminate the unneeded, excess eye relief.

Try smacking the eyepiece sideways into the the palm of your hand to see if you can knock it to the side. Unfortunately, this is a well known problem with these eyepieces. Their optical equivalents, the Meade 5000 HD-60s had no such reported issues.

About once a decade. I always wear eyeglasses with long eye relief eyepieces, so I'm mostly just cleaning off accumulated tree sap that drifted onto the eye lens.

How about an ultralight Dob from one of the custom Dob makers?

Okay, I'm out. I had thought about getting a Clicklock with 47mm extension to replace the eyepiece holder of my GSO CC plus 25mm M48 spacer ring since it works out to the same length. I can't bear the thought of having multi-hundred dollar eyepieces getting stuck in a holder like that, and then having to beat on the CL with a screwdriver handle while an eyepiece is in it to get it to release. It sounds like the CL design is really a work in progress, but Baader doesn't realize it since they have yet to recall them for replacement, or offer a consumer-friendly fix that could be applied to them.

At least with a 900mm focal length, field curvature won't be so bad. It will still have a radius of curvature of about 300mm IIRC, so you can probably get by without a field flattener. So, you want to try a 45mm to 180mm focal length eyepiece with it? You do realize how bright the night sky will appear with 18mm to 72mm exit pupil sizes? You won't be able to make out any nebulosity due to lack of contrast against the bright background. That, and you eye won't be able to take in the entire exit pupil, so you'll be working with a 140mm to 35mm effective aperture at best. Seems like a huge waste of effort, but go for it if you already have all the lenses. Generally, your best bet to take in nebula at low power is night vision gear or other electronically assisted observing.

How about flourinated greases? They're expensive, but so are astro optics.

The Maxvision were indeed leftover Meade 5000 UWA/SWA stock after Ningbo Sunny bought Meade and cancelled their eyepiece contract with JOC (ES/Bresser). As such, they are optically identical to the the ES-82/68 eyepieces.

Just make a spot in the center of the donut with permanent ink or a tiny paint blob before cleaning in case that happens. Soapy water won't generally remove either mark.