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I do a bit of that when the moon is bright as well. Adds some variety 🙂 I've packed in now (wimp !) - keep on trucking @Mr Spock 👍

Balance is ok. I had no issues tracking for the past 3 months I had it and it just stop tracking at the azimuth.

Just took in half a dozen bright and familiar doubles. Back to the moon now:-

Quick snap with the D500 taken just now - 00:45 in the morning

How is the balance of the scope? The clutch can only lift so much, and heavy eyepieces, etc., might be too much for it to handle. If that’s the case, a counterweight on the lower half of the scope might be the solution.

I've an OMI mirror, tested at 532nm (green). Here's their tech note on interferometry results: https://web.archive.org/web/20080509195633/http://www.opticalmechanics.com/technical_articles/interferometric_testing.html The numbers quoted for your mirror are very good!

I notice in the Tak the field curvature seen in the f5 Newt isn't there. I'm guessing therefore it's f related. From 8 all the way down to 3 it's turning in a great performance. The difference between it and high end eyepieces is very small indeed and you could be happy (as a refractor owner) with this as your main eyepiece. I think f5 Newt owners should look elsewhere. For the money it has to be the best bargain ever.

No, you don't need to ever justify a purchase to anyone else (except perhaps your family CFO, if you know what I mean). I'm just trying to figure out what I've been missing with this scope. I'll try some more widefield viewing with it.

Also depends on the OEMs QA requirements including salt spray test specification as to what methods they use. I find for DIY spray paint works well, ensure its done in a ventilated space, if outdoors try not to do it during a breezy day and in an enclosed area as spray travels far in the air (be sure to mask areas if space is limited). Do it in a reasonably medium temp, too cold and there's risk of moisture being present, too warm and it doesn't set (finish) as well but dries quicker. Spray lightly in a few passes intially (say moving 30cm in a second, over again say 3-5 times), then do a thicker slower one time pass on top being careful not to cause drip marks (too heavy/slow with the spray movement). Two or three times with this method leaves a nice even finish as without the quick pass layers the heavy layer is uneven and dries as such. I've done this to match original powder coat quite well as well on vehicles.

Having a great lunar session. Seeing is quite good if a little wobbly. It's the long period wobble you get sometimes. Gassendi N is resolved into a crater and is a fine sight with the rille next to it. A good chance to evaluate eyepieces again - full report to come. The Svbony 3-8 field curvature I noted in the f5 Newt is not evident in the f7.4 apo - interesting. Comparing the 3mm setting, it's very good, falling just short of the 3.3mm TOE and 3.5mm LVW. I prefer the view through the LVW, it has that 'easy on the eye' feel to it. That's another eyepiece better in the f7.4 - in the f5 it's too easy to get blackouts from incorrect eye position. Same. It's an interesting feature. Shame I didn't have the 12" out so I could get a bit more magnification. The south part of the Schiller Annular Plain, or whatever they call it now, is very prominent. Going back out now - there's so much to see yet!

Another slight show from the Aurora, it was very active earlier before dark, ok for the Southern hemisphere. Dodgy phone pic

It's down to one thing in reality: electrocoat. The bodyshells are chemically cleaned in an acid-dip then electro-plated with an epoxy basecoat. This being electro-plated means it achieves 100% coverage, inside and out. It's the layer under the primer and unless it's damaged it'll outlast the vehicle's lifespan.

Interesting, thanks for all the responses. I lean towards Bill Paolini’s thoughts as presented by @JTEC, but local opinion seems to be evenly divided. As for adding heaters to secondaries, I’ve avoided that for the same reasons, and decided that dew-opacity signals “end of session”. Luckily I’ve found that there’ve been overall surprisingly few heavy-dew nights, and this is Ireland! Magnus

Step 1: sandpaper or paint stripper the existing paint off. Step 2: kill the rust. My preferred method is phosphoric acid. Nasty stuff, must be used with a lot of care. Proprietary rust-killers are also available. Step 3. primer, from local motor factors. Step 4. enamel or similar topcoat in colour of your choice, also from motor factors.

Cars have extensive multi stage pre treatment done to the metal as prep prior to paint including galvanisation where applicable. Once the surface gets rust or the bare metal is exposed it's pretty much guaranteed to rust again. Even aluminium goes through similar pre treatments. The best you can do is advised, use a mechanical means to grind the rust off if present (dremels are useful things to have lying around, or a 4 inch angle grinder) unless the corrosion is not too much of a concern.

In these photos, what I am looking for?

Thanks. It seems that I have lost torque to turn the wormwheel and brass when 'tracking' although at higher speed it works; this is with no clutch and large wheel?. Hmmm After shutting down and restarting it turns with and without the wheel?? Most peculiar

2+3 seem to work.

I've used hammerite at work, sadly they bought it in paint pots and we were painting onto paint (valve handles needed to show what the valve carried by colour) Brushing it on wasn't most effective... They looked a bit like a red tar monster when we were done haha. Bare mild steel will corrode very rapidly in wet environments. Rust is also supposedly self-perpetuating and a small amount of rust formation will crack or bubble paint allowing more oxygen access to the metal. I suggest completing rust removal, preferably by wire wheel (you can buy them for home electric drill chucks, flapper wheel may also work). If you want to ensure it's moisture free in the cracks or pits you could always stick the metal in an oven at a skin safe temperature for a few minutes. I need to think about all this myself, as my HEQ5 is starting to look a bit shabby with some parts of it rusting up and the counterweights losing their paintwork... Eventually it just catches rust and there's nothing you can do about it I guess. I suspect modern cars can avoid rusting on bodywork much more easily since they can control the conditions and state of the bare metal much more easily in the factory before applying multiple layers of rust protection below the paint.

Many beginning amateur astronomers will purchase a Donsonian as their first telescope, and it’s an excellent and extremely cost effective choice. Part of Dob ownership includes learning about collimating and cooling the mirrors, improving the primary mirror cell, cleaning the mirrors, and a bunch more, but that’s all part of the experience and with the right tools, knowledge, and attitude, it can add to the enjoyment of owning and observing with your Dob. I’m going to talk about something else that’s just as important as those other activities, but that is much, much, easier. You already know from the title that this thread is about leveling your Dob base, but why is it important to do so? It’s important because if your base isn’t level your telescope may, with assistance from gravity, swing on its own accord away from your target. This can be frustrating because first off you expect the scope to stay where you point it, and when it doesn’t that’s not good. Secondly, you may try to compensate for this behavior by adding in additional friction, but too much friction can make tracking erratic; also, not good. Enough intro, here’s what you’ll need: You’ll need two easily obtained and relatively inexpensive items; a bubble level and a leveling wedge. I went fancy with my bubble level, but I recommend something less fancy like this because large enough and sensitive enough without being too sensitive: https://www.amazon.com/dp/B08ZYKKYY3/?coliid=I17ZPQ49GZF5C6&colid=3DKYFKLVLPA3S&psc=1&ref_=list_c_wl_lv_ov_lig_dp_it I also went fancy with the wedge, which is really a door stop, and it looks like this: https://www.amazon.com/gp/product/B01F6KSDZW/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1 This particular door stop is worth the extravagance because its concave top won’t slip out from under your Dob’s foot, and it’s large enough to accommodate most reasonable slopes. Splurge - you’ll be glad you did. Also helpful to mark the location of the three feet under your Dob are these small self-adhesive dots: https://www.amazon.com/gp/product/B000BMBU9M/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1 Let’s level! Here you see the base plopped down on a fairly steep slope, probably four or five degrees or more. My bubble level is affixed to the top of the Dob base with strong double sided tape so I don’t forget it and leave it behind at the end of a long night’s observing. Note that the alignment line on the level is aligned with the dot on the base, and is also aligned with the center of the base, which is out of view. Also note the location of the bubble at the top, and a bit to the right of, the alignment line. Here’s a lower angle view. Note the yellow dot in the bottom half of the base; it marks the location of one of the three short feet under the base. Here’s the trickiest part because there are two steps. First, align the two dots. Next, and while keeping the two dots aligned together, rotate the Dob base in place until the bubble is split by the alignment line on the bubble level. When you’re done it should look like this: All that is left is to slide your wedge under the foot of the base located below the yellow dot to bring the bubble into the center of your level, as shown. Your base is now level. Without rushing I can easily level the base in way under half a minute. The result is a scope that locates and tracks objects easily, and that stays where it’s pointed. Good luck!

ive had the 152 starwave about 6 months and love it. the red to me looks fantastic. As far as weight goes, im 69 yo and dont think its heavy, i carry it about the house upstairs downstairs and out onto my pier, no problem, there must be some very weak people on here hahaha. Also i observe away from home a lot and use the scope on an AVX mount and a great team they make. Anyone that wants a 152 frac id say go for it.

I'd not come across this book, so thanks all for mentioning it. Turns out you can browse it on the Internet Archive. https://archive.org/details/atlas-of-the-messier-objects-highlights-of-the-deep-sky/page/219/mode/1up (it's the old edition, obviously)

I didn't buy it for planets , that's why I have an 8" SCT .. I bought one (again) for widefield viewing . To me it's the perfect combination ..but of course no scope is perfect and there will be the doubters although I'm not sure why as no opinions were sought.I really like refractors and although I don't dislike reflectors for me they are awkward beasts. ( I have owned many ) . Anyway , not sure why I need to justify a purchase . Ultimately every scope that is bought is inferior in some way .. I suppose in a perfect world we would all buy the James Webb telescope .

Ultra thin too.

Some years ago, with my 250PX, I had problems with slewing and tracking in the Az axis. It turned out to be one of the encoder ribbon cable connectors adrift from its position on the control board's pins. The ribbon cable layout may have been defined before the ferrite rings had been added (probably to pass regulatory EMC tests) and there was little slack in the cables. It was difficult to spot the poor connection, as it was under the control board. The problems went away once I had re-seated the plug, and has been fine since. The clutch friction is a compromise between (1) good motor drive, and (2) manual operation without using the handset. Geoff