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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 works now?? 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

I'll be on it shortly. Put the 100 out and had a quick peek at Gassendi. Perfectly presented. Just let the scope cool a little and we're off.

Aurorawatch sent a red alert earlier, so we walked to a spot out of town with no street lighting and a decent northern horizon. As the last glow faded in the west, we strained our eyes to the north. Was there a faint, mauve tinge to the sky there? We both thought we could see it, but not definitively. Aurorawatch had by now downgraded to yellow, so we headed back. Next time...

Irresponsible behaviour: Nagler 2-4mm zoom on 2mm + 2.2x barlow (the Parks GS 2x is 2.2x really) in a 900mm FL scope = 989x 😬 Apollo astronaut viewpoint gliding over the lunar surface. I'll pretend that the floaters are a dirty command module window 😉 Highly un-scientific, but fun 😄

Hi folks After 6 years or so I am getting back into stargazing 🔭 Previously I had an 8 inch Skywatcher Dob which I struggled with and became too fixated with aligning mirrors to enjoy the skies. Before that I had a beautiful Skywatcher refractor but the equatorial mount took a while to set up and take down. So…currently I’d like something compact and easy to set up and use. I was thinking of the Celestron SE 4inch Maksutov Cassegrain. My interest is mainly planetary. Is this a good choice? Any help and recommendations would be greatly appreciated. Thanks to all Neb

Swapped out my RedCat setup for the Esprit120 which I think I'll be using in visual mode for the next few weeks as it is starting to get light well into the evening. I bought the Esprit 120 about a year ago and I still haven't really put it to work on imaging -I've been having too much fun using the RedCat. So this is really the first proper shakedown with the 120. Tonight I will be mainly looking at the Moon - it looks glorious, nice and sharp and no colour fringes whatsoever. I'm looking forward to playing around with this over the next few weeks, I'm going to keep it in visual mode until the autumn arrives. Jim

I'd give it a clean up with some steel wool then wash off any dust. You can use warm water and fairy liquid, then dry with paper towel and allow to dry on a radiator for a few minutes. Duraglit wool is also good to help clean up any bare metal but also needs cleaning off afterwards. Rust-Oleum sage green spray paying gives a nice finish. It's not an exact match but its close enough not to be obvious. It's also pretty hard wearing once completely dry. It's also cheap, so weights etc can be resprayed whenever necessary.

Good seeing tonight. I've been able to get really sharp and crisp views of Gassendi, it's rilles, central peak and fractured floor using the Svbony 3-8mm zoom (4mm setting) AND a Parks GS barlow which gives a combined magnification of a rather ludicrous 494x. Stepping up to 566x and a touch of the sharpness is lost although the views are still quite impressive. The scope is my old ED120. Schiller looks like a huge divot close to the terminator. The Parks GS barlow is the same optically as the old Celestron Ultima. Nice glass 🙂

You generally don't want to touch the highlights level on the right as it's your brightest parts (ie stars) and if you're not careful you'll oversaturate them and any glow and cause them to bloat. The mid is the control. It's usually better if you're trying to reveal faint signal to work on starless images, then recombine the stars after the stretching is done. This isn't so necessary when doing galaxy processing.

I purchased a Wi-Fi camera for my ‘scopes. I could not get the damn thing to connect. I tried a cheap Tesco CMOS webcam many years ago and a Phillips Toucam ll and although I did not do any imaging at that time, the views certainly made it a great tool for outreach events. Only downside is the length of the USB cables. I now have a secondhand ZWO ASI120MC, so I am looking forward to see how that performs.

The thing with rust which I presume is on it, if it's on the metal it is extremely difficult to get rid of without some sort of real surface grinding and pre treatment, hammerite is supposed to cover the rust and metal but does it continue to rust underneath? When I painted an area on a previous car, even when sanded down to bare shiny metal, a few coats of primer and a few coats of spray paint and lacquer, it still continued to rust a few months after. I suppose this application it isn't so exposed to the elements. With paint you usually want a good keyed (textured) surface so there's something and more surface area to adhere to in the absence of an electro static process. Maybe use a coarse grit sandpaper to finish the surface prior to coating. You can always sand down with wet and dry to smooth it off afterward but needs a few coats of paint prior.

Can I show something that I unexpectedly did see in a 5" Mak that I would have normally expected to see in an 8" Newt? A spider.

Mmm, very interesting, This was actually a specific example I did wonder might be easier in the frac., without diffraction spikes, and very uneven brightness.