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Although I've owned a pair of Celestron Skymaster 20x80s for over six years now, but because they went badly out of collimation, I haven't used them for ages. I sent them back to Celestron, but, apparently, they couldn't be repaired. Amazingly, though, they gave me a brand new pair (!), and these arrived yesterday.
Once mounted on the tripod I took a look at the 69% waxing Moon. Absolutely incredible view! Sharp, bright, big, three-dimensional, and only the very slightest hint of chromatic aberration. Kept coming back to this over the course of the evening.
Next up M31 and M33. Although quite washed out by the moonlight (as was everything I looked at), I was amazed at the brightness, the size, and the hint of detail in M31. Again, the three-dimensionality was obvious. M33 was only just visible.
Open clusters: Double cluster, Owl cluster, Coathanger – all were fantastic, with a variety of star colours obvious, and only a hint of distortion around the edge of the fov (really had to drag my eyes away from the objects in the middle of the fov to experience it). The Coathanger pretty much filled the fov, and was pin sharp and bright.
Double stars: Epsilon Lyrae, a very easy split, as was Albireo (again, the different colours were obvious). Mesarthim was just too tight to split. In passing, one of the things that amazed me the most last night was star colour. Mirach, Algol, Vega and many others were all pin sharp, bright, and their colours were very obvious.
Globulars: M15 and 92 were small and dense fuzzy balls, M13 bigger, brighter, and with just a hint of granulation to it (like the Moon, I kept coming back to M13).
Ring nebula: The ring shape was obvious, even at x20, though small.
Being a work night, I was back indoors by about 10, but although just a brief session, it was hugely enjoyable, and a real buzz to be using 20x80 bins again.
Been a while since I have been on the site – work has been really busy these last 18 months, and although it’s still manic, things are slowing down a bit!!
Viewing my previous posts, you will see that I was in the market for a new scope to adorn my EQ3-2 mount that I had purchased ages ago now!! Well, things didn’t turn out as expected, and while I am still hoping to get a scope, hopefully at Christmas if Santa is kind to me (I have been a good boy lol!!) I decided to get a pair of Binoculars to fill the gap!
Budget was tight, and I did want a pair of larger aperture bins. A lot of reading up on the internet, and I settled on the Celestron Skymaster 20x80’s. I already have a pair of 10x50’s so was after something with a bit more power, and larger objective’s. The skymasters seemed to fit the bill, and the price was right as well! I dropped into Rother Valley Optics with my cash on the off chance they would have a pair in stock – they didn’t, so I left my details, and less than 24 hours later, Adam from the shop called me to say they had a pair in! I drove over to their shop, tried them out outside the shop, as I had read that some pairs are known to have collimation issues. These where perfect, so I parted with my £99 cash and went home with them! First class service from RVO, and I will be using them again when it comes to getting my scope – thanks guys!
So, onto the bin’s. They came double boxed up, and within the branded box inside the plain box, the bin’s were securely packed in foam and wrapped in plastic. They come with a basic carry case, which won’t protect them from hard knocks, but will keep the dust off them while not in use. The eye pieces are protected by a one piece cover, while each large objective is covered by its own, separate cover. There is also a basic neck strap, but it appears quite flimsy, and I won’t be using it.
The bins have a built in tripod adaptor, on an adjustable slider, meaning they can be securely attached to a tripod and balanced up. Weight wise, they tip the scales at just over 2.6kg. This isn’t hugely heavy, and while I did use a tripod for some observing, when I wanted to look at things nearer the zenith, I hand held them, and did so for quite some time. I didn’t feel they were overly heavy, even after prolonged use.
It seems that new scope curse also affects owners of new binoculars, as I had to wait 5 days for clear skies!! I went out at about 10:30pm into the back garden, and while the side of house has a street lamp directly over the hedge, round the back its cut off, and quite dark. I began by finding M31, which at is currently nearly at the Zenith. I could see the central core clearly, and with some averted vision, make out some finer details in the disk. Moving on to M45, the Pleiades, that was just rising over my neighbours fence – what a sight!! Even though it was quite low down, the cluster filled the view, and I could see loads of fainter stars within it. Moving through the Milkyway, the view was filled with thousands of stars and star clusters!! I was really impressed. I intend to go to a dark sky site up in the Peak District, just north of Ashbourne when time and the weather permit, to get some proper dark sky viewing in!
I have not yet been able to look at the Moon or any planets through them – the Moon hadn’t risen by the time I turned in, and is now a very small waning crescent. I will have to wait a bit longer, and will update the review once done. Mars was up, but low in the sky, and due to the street lights, swamped with LP.
With terrestrial viewing, they provide bright and crisp views. While there is some CA when looking at things with bright edges, general viewing wasn’t affected in any way. I plan to take them to my local nature reserve to test them out on some wild life as well. I am also a bit of a plane fan, and when time permits I park up near East Midlands Airport to watch the aircraft coming and going – these will be great for that, set up on my tripod for easy viewing!
Conclusion – the Skymaster 20x80’s are a decent pair of binoculars. While they don’t have the build quality of more expensive ones, treated well I can see no reason why they won’t last for years. They actually come with a 5 year Celestron guarantee anyway! For causal use when you don’t want to set up the main scope I think these fit the bill nicely, and I would recommend them to anyone.
Bit of background info first.
Having problems auto aligning my Meade 8" LX90GPS. Works at home Liverpool, but not at my site in Hadnall. Doesn't do LNT, not level and never finds north, just spins around like a dalek! Thought LNT module was duff or damaged in transport. Tried everything, then noticed my phone was off north too, tried two other phones, none of the three ever showed same north at same time, even after calibration.
Then to my amazement one of the phones suddenly flashed up High Magnetic Anomalies. Moved 20 metres away and ok.
So upshot is that under the ground below where I can view from is either a metal dump or electric cables or some other magnetic force. Can't dig it up, decked over. Can't move further away it's beyond my fence line!!!!!
So now to finders.. Can't get on with the red dot LNT module for alignment, too flimsy and to big a dot and useless for auto align as above.
So want a decent optical finder, to sight and alugn manually so criteria are
About £100 all in. Not straight through back can't contort any more....
So need RA but is RACI really better than just RA for the extra cost.
6x30 is it too small mag, maybe 8x50, 9x50 or look for used 10x60 or is that too big.
Any ideas or what else do I need to consider, some say EPs are fixed, is this ok or not. Looked at DIY, but the mounts are soooooo... expensive too.
Hope this makes sense and look forward to your help.
By Ben the Ignorant
Don't blame me for the silly pun, Tele Vue actually used it in their ads back in the days when they were written on paper. Now that you are enlightened by this piece of trivia in the history of advertising, here's the topic. My urban observing spots are surrounded by public lamps so I need complete blackening in my finders as well as my scopes, or arcs of light and various shapeless flares will show when I don't aim high. Little stars in a 30mm scope can't compete, star-hopping is made difficult.
This is how I do the blackening. I start with the amici prism.
Cleaning it with alcohol proved necessary, some grease was on the exposed faces.
Next I paint the rough surfaces with a sharpie.
And the rough edges, too.
When all non-polished places are black, funny, it's actually possible to make the prism look all black from a certain angle.
Then its housing was not cleanly put out of its mold. I don't like finding uneven stuff, so I rectified it even it if was not important for the finder's function.
40-grit did the job in a couple minutes.
The plate side is rough from the 40-grit paper but is now planed, the plate will screw onto it without leaving gaps.
From its usable angles the prism now looks like that: a clear window with black sides that will absorb stray light. Larger amici prisms for full-size scopes might require the same treatment; practicing on cheaper stuff makes it less intimidating.
The housing is garnished with blackboard paint. See how the inside and the barrel are darker than the surface with the screw holes. This paint is water-based, doesn't smell, dries in minutes, and can be removed from places it covers by accident, just scrape it and rub with a wet towel, not a trace will remain. But it sticks hard enough to not chip over time. Have you seen you school's blackboard chip?
The sharpie also cures the objective lenses' rough edges disease. Another funny effect, when the side is barely half-blackened, the untreated edge already looks gray, as if black could reflect on other things; this is promising for the final effect!
The promise is kept! In main scopes or finders, this black ring will kill off nearly all the light that touches it, I can guarantee it from experience!
The dewshield (made in the proper length by Sky-Watcher, by the way, congrats!) is also painted. See how the bare anodized aluminum ring at the rear is shiny. I don't paint that area or the doublet won't enter. Its own layer of sharpie paint plus the blackboard paint would be too much. Where are all those white dust specks coming from?
The retaining ring is a treacherous spot in telescopes because the total area is large even if the thing is narrow, can't leave it shiny, especially at those grazing angles! See the difference with the threaded outside of it. Not an essential job in a finder but done it a minute, so why not?
The eyepiece lenses were white on the side, too, Before the sharpie touch, the objective was that white and bright, but you'd be surprised how quickly the non-yet-painted part turns dark gray when you start painting the rest. The inside of these retaining rings will receive the blackboard touch.
Now that's how things should look! Both the lenses and their bevels are coated in black. The bevels seem a bit shiny from this angle but their absorption of bad light is vastly better. The eyepiece is a simple Plössl, only two cemented doublets with rounder bellies facing each other, mounting them right is foolproof, unlike other optical designs. You can improve the contrast in unexpensive and simple eyepieces with a good blackening. Costs nothing, proportionate to the thing's price. The eyepiece is fully-multi-coated, by the way, more congrats to Sky-Watcher for taking accessories seriously.
Another improvement: the tiny original screws are replaced by homemade larger screws. Those white plugs are used in the assembly of furniture, but only one tool store had them, and only once. I bought the two packs they had, can't find them anymore, anonymous packaging. They include a piece of threaded 6mm rod of the right length, just had to plane the tip. I superglue a stainless washer at the top, and fill the space with O-rings. Only those at the outside need to be glued, the others are pinched between them. Just seeing the screws makes the advantages obvious, compare with the two original plastic screws. Hard to grab with gloves, or even without gloves for that matter.
Now the flocking. The foam side of adhesive velcro is ideal for small areas. I don't glue it to the tube because that would make replacement messy. Instead, I glue it on a strip of paper.
Then I fold it into a loop, and tape it. It's not round now but it will when it's forced inside the tube. That might be a useful trick when flocking larger tubes; glueing directly onto the tube allows no mistake, and can force you to leave a poorly applied flocking if it sticks too hard. Can't remove that thing but I need to adjust it! GRRRRR!!
The finder is so short, only two rings did the job. Do not put that too close to the objective or it will enter the light cone. So, a few millimeters are not flocked but that's okay because the tube was already painted flat black, and all the rest of the finder is treated. Sky-Watcher put a sensible baffle in the back.
There, the light cone is not eaten up by the foam, we have a clear view of the optics' edges from objective to eyepiece. The criteria are the same for bigger refractors.
Before any flocking and blackening was done, the inside of the eyepiece was that shiny, the reflection on the side is very bright! Pic taken through the completely assembled finder.
It was very tough getting a pic at the same angle, the flat camera objective is hard to position as accurately as the eye with its round cornea, but it's clear the lateral reflections are much dimmer. Again, picture taken through the complete finder even if it might look like the eyepiece was removed from the tube.
Before the black-ops job.
After the ninjas came. Sorry if the shot is blurry but the brightness comparison still stands. The area around the pupil is darker, and even the inside of the eyecup is darker since I applied a little blackboard paint there, too. It's shiny on the top picture but matte here.
And if the difference does not impress you, see how the tests shots were made: with this setup, flashlight at an angle, and only one inch from the dewshield. Note how a few extra O-rings between the objective cell and the finder bracket keep it from playing. Another set of O-rings between the prism housing and the bracket complete the task. Finders moving fore and aft, and allowed to rotate lose alignment. Thanks to the firm push of these rubber rings, the tube is held tight but free to be adjusted.
I had to buy a few O-rings for something non-astro, but of course you have to take the whole box. Not liking to leave tools unused, I looked for ways to make these rings profitable. One of the useful tasks was as loosened screw safety. This finder won't fall off to the ground.
She's not missing anymore.