Louis D

You should qualify that with effective field stop for negative-positive designs. I know for a fact that the physical field stop of the 12mm ES-92 is 51mm in diameter because I measured it with a micrometer in my surplussed version of it that lacks its Smyth group. Due to vignetting or some other artifact, it measures out as a 48.4mm field stop diameter photographically when used in a scope, however. It requires about 21mm extra in focus relative to its shoulder to reach focus because the field stop is so far above the shoulder. If its off-axis chromatic aberrations could be reigned in with an appropriate corrector lens, it would make for a fantastic widest field eyepiece. I was just out last night quite happily cruising the Orion constellation with it in a 6" f/5 GSO Newt. If you look straight on axis, the chromatic aberrations are all but undetectable in peripheral vision. Eye relief is fantastic and the enormous 92 degree AFOV is easy to hold thanks to very little SAEP with the Smyth group gone. The higher magnification and slightly wider TFOV than my 40mm Meade 5000 SWA or 40mm Pentax XW-R make the view much more engaging than either of those 40mm options.

You're mixing up objective lens diameter which does indeed collect more light the larger they get with eyepiece field stop diameter which simply controls the extent of the projected image circle visible in the apparent field of view (AFOV) which then equates to the true field of view (TFOV). A 2" eyepiece may or may not show more TFOV than a 1.25" eyepiece of the same focal length. It depends on the diameter of the field stop. It also depends on the size of the eyepiece's field lens (the bottom-most one) to a lesser extent. An oversized field lens has no effect on TFOV, but an undersized field lens can lead to edge vignetting. In general, a 2" eyepiece will indeed have a larger AFOV than a 1.25" eyepiece given the same eyepiece focal length, but not always. Sometimes, the designer(s) chose to package the eyepiece in a 2" barrel simply due to weight and bulk concerns overwhelming a 1.25" focuser and/or diagonal. Sometimes the choice was made because there would have been some vignetting if they hadn't. The classic example of this choice is the 17mm Nagler T4 in a 2" barrel versus the 18mm Meade 5000 UWA in a 1.25" package. Both are/were 82 degree AFOV eyepieces, but the latter suffers from edge vignetting while the former does not.

At a summer internship. She doesn't take kindly to being slighted.

Ouch!!! Watch out for a frying pan to the backside of your head. 😂

It looks to be from the same family of scopes as the Orion SkyQuest XT Classic Dobsonians.

If you're not looking for eye astigmatism artifacts, you might not notice them. It's the same for coma from the primary mirror.

And prices. It's absurd what Baader charges for the BHAs.

They were a good budget option 5+ years ago, then their prices climbed into near Tele Vue territory even pre-pandemic, at least here in the US. There's a bit of a sale on ES-82s here right now; but even then, the Nirvana ES are a much better value.

In the US within most city limits, if a concrete pad is poured under the structure, it may be classified as permanent and needs permits/inspections and will be taxed as real estate property depending on size or other considerations. Many US counties outside of city limits don't have such rules about permits/inspections, but you will still probably be property taxed on it if they find out it exists. Homeowners insurance will generally cover damage to such structures. If there was no concrete pad under it that it will be attached to, it is generally considered a portable structure, and generally won't be permitted/inspected/taxed unless it is over certain size limits. Homeowners insurance generally covers damage to these types of structures and their contents as well. They are covered under the "other structures" portion and may have different limits than structures attached to the main house. Contents may be covered at cash value rather than replacement value, depending on the policy. So, was the carport attached to the main house? Was it permanently attached to a concrete slab? How big was it? Is it in the property tax appraisal roles? The answers to these questions may help to determine the classification of the structure and insurance coverage limits. Either way, it may be worth discussing with your insurance company because they might cover the damage and go after the other homeowner for reimbursement via subrogation.

I remember trying that with a pair of surplus prisms cemented at 90 degrees in a home brew finder scope in the late 90s. IIRC, it does work, but you have to stand at 90 degrees to the OTA, facing the hypotenuse side of the eyepiece holding diagonal to get the image in the right orientation. Otherwise, it's rotated 90 degrees if you stand behind your OTA.

Try loosening all the primary collimation screws equal amounts to let the primary move forward toward the secondary until the Barlow reaches focus again. Then, tweak the primary's collimation back to where it was before, only this time further upward in the tube.

Look over the pond. Agena has it as GSO, High Point has it as Apertura, and OPT has it as TPO, and all have it in stock. I have no idea what's going on with UK retailers and GSO products.

It's not perfect to the edge, but it is very good and has enough eye relief to use comfortably with eyeglasses. If you have a two inch focuser, I much prefer the Omegon Redline 22mm and their kin (I have the Astro-Tech AF70 version) at that focal length range. I'm not sure how much better either is than your Baader Hyperion 21mm, though. I've never looked through any BH. I eventually found an affordable used Nagler T4 22mm and use it preferentially in that focal length range now. It's close to perfect to the edge with very mild field curvature, astigmatism, and SAEP. I guess I would ask what it is about your BH 21mm that makes you want to swap it out for a different eyepiece. Check this post of mine for comparison images through my eyepieces. The 22mm to 24mm ranges (two separate groups) are toward the lower middle of that post and will give you some idea of how each performs at f/6 relative to each other: The APM UFF 24, AT AF70 22mm, and NT4 22mm are all in there.

Ernest tested both, and seems to think they're the same optically. They test pretty much the same and measure pretty much the same. Celestron X-Cel LX 9mm Meade 5000 HD-60 9mm My take on the entire Meade HD-60 line:

I have had the original Vixen LV 9mm for 25 years. It is sharp edge to edge, but it views a bit dark for its focal length and views rather Plossl-like at 50° AFOV. Some folks have attributed this darkening to its use of Lanthanum glass. It is very easy to hold the view even with eyeglasses. However, I've retired it in favor a 9mm Morpheus and 10mm Delos. I much prefer their wider apparent field of views and "brighter" views. Both are easily as sharp if not sharper than the Vixen LV. The Meade HD-60 9mm is also an excellent eyepiece just a step behind the 9mm Morpheus and significantly wider in AFOV (measured at 62° by me) than the LV (measured at 48° by me). If you're using a tracking mount, the difference may not matter all that much to you.

Scope aside, that's a gorgeous view out your windows.

Not in Texas in the summer. It is about 75° F in my house thanks to A/C, and it can be 95° F or more outside after sunset. I often have to let my scope(s) warm up rather than cool down to acclimate. On some nights, it never gets below about 80° F before sunrise, so it's never as cool outside as inside. Believe me, warming up causes just as many optical issues as cooling down.

I wear a pair of distance-only eyeglasses at the eyepiece to correct my 2 diopters of astigmatism. I bought them online for about $20. Make sure to get the lowest index plastic lenses to minimize chromatic aberrations at the edge when looking off axis through them with wide field eyepieces.

If you don't need long eye relief, the new Svbony 3-8mm zoom eyepiece is excellent from 5-8mm and very good from 3-5mm. However, I'd start with a decent mid-power wide field in the 12mm to 16mm range. There are a lot of good options depending on your budget.

Was this windstorm beyond anything anyone could have anticipated like a strong tornado or hurricane of epic proportions? If not, the neighbor should be held legally responsible for not adequately securing their car port against typical weather forces for the area.

I was going to suggest that as well. However, FLO is sold out of them right now. I bought the 2.5mm version direct from China for about $35 shipped a few months back. It is quite good, especially when you figure in the cost. Check on ebay UK for sellers that have the focal lengths you want in stock. I'd stick with the ones with the shiny metal bands on the twist up cup. That's the version I have. The Skywatcher version seems to come from another factory. Here's a write-up of four versions of the 4mm focal length Planetary 58 eyepiece:

Experienced observer Jon Isaacs over on CN also has issues with the 3.2mm BST off axis. He prefers the 5mm BST Barlowed. The 3.2mm Paradigm (BST Starguider) is the only one I don't have and have never looked through, but the 5mm that I do have is quite good. If you've got the budget, the 3.5mm Pentax XW is basically flawless. However, it's a rare night even here in Texas that it shows any more detail on an object than my 5.2mm Pentax XL, so I don't tend to use it much. Perhaps if I had an f/4 Dob it might see more use.

Just be cautious of overloading your Skytee 2. The late @johninderby had his snap off under load, but was able to grab his OTA before it hit the ground: The mount is made of cast pot metal rather than being CNC machined from a solid billet of aluminum.

No, not even remotely close. The highest sales tax anywhere in the US is 13.725% in one municipality. The average across all states, however, is 5%. Four states have no sales tax at all. You paid 4.6 times as much in VAT as the average American pays in sales tax. Most states don't tax food and medicine, either.

Thanks for the feedback. I'm an engineer who enjoys finding solutions to problems. The problem here is how to get the best performance out of fast achromatic refractors. There have been expensive solutions in the past (the Aries Chromacor), but I was intrigued by the possibility of simply improving rather than correcting the view. I've been using my retired 14mm Pentax XL in a Parks GS 2x shorty Barlow for the testing at about 57x. I place the object slightly off center to allow for more drift time on my undriven alt-az mount. I then grab two filters, one in each hand, carefully by their edges (they're all in a shallow box nearby to avoid them disappearing into the lawn). Next, I return to the eyepiece and move each eyepiece in and out of the exiting light cone using a variation on the blink comparator method to look for changes. I sometimes move one, then the other, then both at the same time, into the light cone. I even alternate which one is stationary while moving the other one in and out to observe what changes occur when stacking to better understand what each filter is doing. This method only works with small objects like planets and stars since I can only see a small portion of the FOV while pulled back so far from the eyepiece to fit one, and sometimes two, filters in between my eye and the eyepiece. I chose the Pentax XL because it has a smooth top with a rubber guard, so I wouldn't have snagging issues or eye lens scratching issues. It also has no chromatic aberration issues of its own, so I wouldn't have to sort eyepiece chromatism from scope chromatism. Lastly, since it was retired by my 14mm Morpheus, I wouldn't be too upset if something were to happen to it. Grabbing the filters without putting fingerprints on them is difficult, but practice makes perfect. Overall, I've been really surprised and enlightened by my discoveries. I can't recall anyone else systematically comparing various filters on an achromat to narrow in on what works well and what doesn't. There's been lots of work done in the area of figuring out which filters work best on which objects, but they always seem to assume the scope doesn't have strong chromatism of its own to sort through as well. Often, folks write off fast achromats for planetary usage, but I've found that with the proper filtering, they can put up quite sharp and pleasing images if you can ignore the color cast. Surprisingly, I've found my brain performs a white balance on pale yellow and yellow-green images over time such that they seem color cast free. There's also the fun of playing with my toys in a new way. As a kid, I used to combine my toys in new and unusual ways such as racing my Hot Wheels cars down tracks through long Lincoln Log cabins built over the track. I was amused by the change in sound as they went through the cabin and how they disappeared and reappeared. So, I'm always looking for new ways to combine things in ways that haven't been done before.