Louis D

A 2" Barlow will severely vignette/cutoff longer (22mm+) widest field eyepieces. You're better off going with a telecentric magnifier as @johninderby suggests above. If you want to go cheap but good and are willing to deal with loss of field, the GSO/Revelation/etc. 2" 2x ED Barlow is hard to beat, especially used. They typically go for about $60 used here in the states.

Alright, I'll come to the defense of 40mm SWA eyepieces at f/6 under Bortle 6 skies. I enjoy maxing out the field of view while viewing large objects like the Pleiades or Collinder 70. They're bright enough that the brighter sky background isn't distracting at all. They're also enjoyable for sweeping rich star fields. Yes, they're marginally useful for detecting smaller DSOs due to the low contrast with the brighter sky background, so higher power and wider field of view eyepieces are more useful.

Probably an M3, possibly an M4, screw. Take one down to your local big box home improvement store and screw it into their thread sizer mounted on a column in the fasteners aisle to find out for sure.

I've been using a Celestron 94108 90° correct image diagonal for 20+ years in my 60mm finder scope to good effect. I can't seem to locate it at any retailers these days, though.

From what I've read, the 4.5mm and 6.5mm Morpheus have less eye relief than the longer focal length ones. As a result, you need to get your eye closer to the eye lens to take in the entire field of view as you found out. Try removing the extension ring and see if the vignetting goes away. As for the difficulty holding the view in them, it sounds like SAEP (Spherical Aberration of the Exit Pupil) or kidney beaning. I've experienced the same issue with the 12mm and 17mm Nagler T4s. It wasn't until I took images through them using a 127 Mak and a slow, extreme wide angle phone camera that I figured out they had SAEP. The two together seem to really expose undiagnosed SAEP. Try using those two Morpheus eyepieces to look at the full moon, and see if you get fleeting kidney bean shadows midway to the field stop. Also, try using them on a bright day terrestrially to expose the issue. The key thing is, your eye's iris must be significantly stopped down from wide open to see it. Here's an image I composited of SAEP as seen through various eyepieces using the technique above. By holding the camera perfectly centered and at the exact exit pupil, SAEP is revealed to be a continuous ring shadow. It explains why a lot of folks don't get on well with the 12mm ES-92, but do fine with 17mm version. Notice how within an eyepiece line that SAEP grows worse with decreasing eyepiece focal length. This might be what's happening within the Morpheus line as well. I find it interesting that some eyepieces have a shadow in the dead center as well as the ring or in lieu of it. I have yet to find a good explanation for that phenomenon, though. The rainbow rings are caused by CAEP (Chromatic Aberration of the Exit Pupil) where different wavelengths of light focus at different distances behind the eye lens. This leads to the "ring of fire" effect.

I don't think it's possible with the maximum field of view of an 8" SCT being about 1.4 degrees and the Pleiades being about 1.8 degrees. Even in an 8" Dob with a 1200mm FL, it's a bit of a tight fit. You can't combine an F/R with a 2" diagonal and widest field 2" eyepieces without severe vignetting. The cheapest route is generally the F/R if you've already got a 32mm Plossl or 24mm SWA eyepiece.

Of course, in Japan, this might be one reason why straight through viewing is popular.

There's the GSO diagonals sold under the Revelation and iOptron brands in the UK as well. I really like their 2" diagonals, but have no direct experience with their 1.25" diagonals. One advantage to prism diagonals over dielectric diagonals is lower scatter.

Not having looked through an ES68 24mm, I wouldn't know. I have strong astigmatism, so I wear eyeglasses at the eyepiece; and the ES doesn't have enough eye relief for me to view the entire field while the APM does. From what I've read online, the APM is at least as good as the ES, just not as good as a 24mm Panoptic.

It's my neighbors' back porch lights that light up my backyard. There's not much I can do about them other than asking them to shut them off when no one is in their backyard. Some are sympathetic, others feel safer keeping their yard floodlit at night and refuse to change their ways.

Not always obvious to newbies, but a planisphere is easiest to use by aligning it with the sky by holding it over your head so E/W/N/S on it align with those of the sky instead of two being flipped.

I would avoid any alt-az mount that places the load above the alt axis. They tend to tip over backward above about 45 degrees due to the imbalance. That rules out the first two. EQ (specifically, GEM) mounts can be frustrating for beginners doing visual only. Their only advantage for visual is you need turn only one knob to keep an object in view once roughly polar aligned. They also tend to be over-taxed in these beginner kits and can be very wobbly/shaky as a result. There are quite a few really good alt-az mounts out there, but they are mostly out of your price range before you even add a telescope OTA. That leaves you with the 6" Dob as your best bet, though shipping to DR could be quite high due to its size. You'd want to also get a cheshire tube or similar to check and perform collimation on it.

What objects are you trying to image? Plus, this might be better asked in an imaging forum.

Certainly worth a lot more than they were a year and a half ago. Check the classifieds for your region to get some idea of what others have been asking. Here in the US, it's been about 85% of 2019 MSRP lately for desirable items.

If you're careful with a green laser pointer, you could swing the telescope onto the target while sighting it through the bins. I've been at star parties where one person puts a scope on a target and lights up the point in the sky with a laser that other scope owners can then align onto since there's little to no parallax.

I keep my tripod fully retracted and closed. It sits in the front corner of the hall closet by the door hinges. Coats keep it from teetering over. The refractor sits in a case at the back of the closet behind the coats, again not taking up much space. How big is your refractor and mount? Do you have no closets whatsoever? Perhaps it's time to declutter them if they're stuffed to the gills.

I've never heard of using beer (India Pale Ale) to clean sensors. At least you'll have something to drink when you're done. 😉

Unless you're in a desert, then moisture issues are all but nonexistent. I've been looking at a second home near Mayhill, New Mexico where lots of folks have observatories.

Makes me glad my secondary is mounted on a separate screw that adjusts for height, leaving the tilt adjusters free to do only that job.

If there's enough moisture, fungus doesn't care. I've had mushrooms grow in my yard during the summer after heavy rains despite 100 degree F temps, full Texas sun, and lots of fresh air via breezes. That's why I keep all my optics in my cooled and heated house. Despite being stored in cases, I've never had fungus issues with any of my astro or photographic gear for over 30 years doing this. My garage also has no fungus issues because it's surrounded on three sides by temperature controlled rooms and has plenty of ventilation via the large door gaps. My shed, though, is another story. It sits at the low point of my lot in the shade and has moisture issues. To do it all over again, I'd raise it a foot off the ground, put a vapor barrier under the floor, and add lots of ventilation.

Keep a small warming element under the scope with a cover over it to keep it above the dew point. A 40W oven bulb would work.

Sorry to hear it didn't work out for you. What have you replaced it with?

There's one screw that bears on the pinion and one that bears directly on the tube. I would adjust each to discover what combination of tension on each works best for your situation.

Unless this is going into an observatory or your wife is an accomplished weight lifter, I would advise against such a heavy telescope starting out. For the moon and planets, a 127 Mak on an alt-az mount will more than suffice. Just give it 30 minutes to an hour to acclimate outdoors before using it. There are two main flavors of them. There are the more plentiful Synta versions which are actually 118mm of clear aperture, 1500mm focal length, and sold under Orion, Celestron, and Sky-Watcher brands. I have two of them, and they work terrifically well even though both were bought used. Then there are the JOC versions which are a true 127mm of clear aperture, 1900mm focal length, and sold under the Explore Scientific and Bresser brands. I have no experience with them, but they also get rave reviews. For either one, I highly recommend purchasing a 50mm RACI (Right Angle Correct Image) finder to help put the scope on target because their field of view is so narrow thanks to their long focal lengths.

Don't forget that the Chinese government also designates certain products and sectors to be strategic and receive generous (often indirect via governmental purchasing) subsidies, such as metals production and solar panel production. There are always disputes being filed in the WTO courts about this. I doubt amateur telescopes fall into this category, but if these same manufacturers receive generous government orders for optics, it can help cover low margin consumer production. China also has very lax labor, consumer protection, and environmental laws as well that help to keep costs down. Remember the whole tainted Chinese baby formula episode a while back? The US has also seen tainted dog treats coming from China. They're at a similar industrial laws point that the US was at around 1900.