Cosmic Geoff

Why pay £25 for the Amazon supply, capable of delivering 24v and zapping your kit, when you can buy a switched-mode supply rated for astro use at 5 amps at +12v, and rated for outdoor use including low temperatures? Lynx Astro 12v DC 5A Low Noise Power Supply | First Light Optics Cheaper than a battery power tank.

Dew shields are a non-optional accessory for SCTS, just like refractors always have a dew shield. The reason manufacturers don't provide them for SCTs is presumably because it makes their product look ugly and adds a small cost. Depending on the depth of your pocket and the severity of local conditions, you can use a home-made cardboard or foam plastic shield, a purchased dew shield, or (in the case of Celestron) a smart-looking black metal shield and a heated ring that replaces the corrector plate retention ring. The dew shield works by preventing the relevant parts of the telescope radiating heat to the (very cold) night sky and becoming cold enough to condense moisture.

Did you get a manual with it? If not, download the Skywatcher manual for the HEQ5 as a .pdf and print it out. And study it. Quite of the information you may find online is misleading. You need to mechanically polar align the mount - roughly for visual use and more accurately for astrophotography. The "home position" has the telescope OTA above the mount and pointed at the north celestial pole (close to Polaris). The GoTo mount will use the home position as a reference when starting a star alignment, or when resuming from Park.

It would be helpful if you explained what you intended to do with that camera and 5 SE and ASIAR, and whether you expect your 11 year old daughter to be able to operate it. From the information you have provided, I would say that this combination of kit is not going to do anything useful. The 5 SE is not suitable for deep-space astrophotography. If you want to do planetary astrophotography, a colour camera would be a better choice, and an ASIAR will not be needed.

Earlier this year I used a 50mm aperture f4 finder/guider to image that bright comet that received a lot of attention. (C/2022 E3 ZTF). I used it with an ASI224MC. Mainly I wanted to ensure I got the whole comet in the field. Yes, it did work, but I got better images with a 102mm f5 refractor. OTOH, if I want to take a widefield shot again I will know what to do.

Having guilty feelings about using GoTo is faintly absurd. There is no "rule" that says amateur astronomers have to find objects the old -fashioned Victorian way. But hold on a minute - Victorian observers often had the advantage of having brass setting circles of a useful size , which modern mounts don't have, and dark skies in urban areas, which we don't have either. And without electronics the whole pursuit of modern digital astrophotography would be impossible. So if you enjoy using GoTo, use it and don't feel guilty.

You need to make some attempt to match the effective focal ratio to the pixel size of the camera. This means that with larger pixel sizes and fast telescopes you need a Barlow. The newer dedicated planetary cameras often have 2.9um pixels which will match with a f10 SCT without requiring a Barlow lens. In practice a dedicated planetary camera is likely to be easier to use and offer a higher video frame rate than a DSLR.

If budget is limited, note that pallet-loads of refurbished business laptops are available on Ebay for far less than the cost of a new one, so you should be able to find something suitable. I bought a Dell Vostro, about 6 years old, with Win10, 7th gen. i5 processor, 8GB memory and 256GB SSD for a trivial sum and use it for EAA and planetary imaging. It plate-solves quickly too. I suggest you don't buy anything below this spec, and in particular avoid older machines with hard drive, as these are power hogs. I note in passing that you can buy a new Win 10 laptop for £100 or less (!) but the performance is what you'd expect considering that a new laptop can cost up to £4000. So avoid the cheapies.

To bring this back to topic: It looked like the bolt I found that fitted the plate in the base of my SLT was either 1/4" BSW or 1/4" UNC. I had a thought last night and tried screwing a couple of camera tripods into the base of the SLT mount. Both fitted perfectly. Looking up the camera tripod thread, I find it is 1/4 20 UNC So that answers the original poster's question. Just to kill off the 11mm suggestion: 11mm is a lot bigger than 1/4". My SLT also has a rectangular label stuck to the underside, but it has something completely different printed on it.

I have a screw that fits that threaded hole. I made an adaptor from SLT head to EQ-5 mount, and the screw in question is a coarse thread, which I think is a British 1/4" BSW thread. But I just found a screw in the junkbox that fitted, so I could be wrong.

I found that my Celestron CPC800 would occasionally malfunction when directed via GoTo to near the zenith (80 to 90 deg altitude). Instead of slewing to target, it would just keep moving slowly past the 90 deg altitude. I could regain control by stopping it with the handset and redirecting it somewhere else. I never did find out what the problem was.

That same error is a straightforward DIY fix on a Celestron SLT mount - just reload the mount (not handset) firmware. It actually means 'no response from mount'. If that doesn't work, check connectors.

We could help you more if you gave more detail. If you are measuring the internal diameter of your bowl as 9.8cm. a SLT mount will not fit.

It could be for guiding, or for connecting the RA +DEC hand controller which does not appear in your photos.

The SLT mount head sits in a bowl with an internal diameter of 125mm at the top. Why do you want to fit the SLT mount to the 80GTL tripod?

No idea. Which items do you have? I can measure up the SLT bowl so you can compare it with the 80GTL bowl. What are you trying to achieve? If the 80GTL mount is built for a lighter scope than the SLT mount, mounting a scope like a 127mm Mak (the heaviest recommended for the SLT mount and tripod) will not go well.

The current AVX and CGX both have 2" steel legs. The legs on a SE 6/8 are much thinner.

First of all, note that the Prinz 330 is potentially a good-quality telescope, and made in Japan. As for the mount, I should think there is little chance of securing replacement parts. It is not clear what the effect of the breakage is. If the mount can be operated by turning the black knob, you could just leave it as-is. Otherwise, your best move would be to find a mechanical engineer who can effect a repair. In theory, you could have the telescope put on a better modern mount, but I anticipate this would cost far more than you paid for the whole outfit.

The Dwarf2 (already available) and Seestar S50 (coming soon) are apparently intended for EVA style quick imaging rather than traditional astrophotography. I have done EVA (electronically assisted visual astronomy) with a 102mm f5 achro, ASI224MC camera and EQ5 Synscan mount, + laptop - all gear I had already. The Seestar S50 does the same thing, but in a much smaller and more automated package.

Buying a used AVX would be a sensible move if you want to stick with Celestron. The Nexstar system is relatively easy to use. Or a used Skywatcher EQ5 Synscan if you prefer. The load capacity is slightly less than the AVX, IIRC. A resurrected CG5 GoTo would not be a great choice from what I've read, even if you could find the parts and they fit a 20 year old mount. Somebody somewhere might want a manual CG5.

If you intend to do anything with the Celestron mount it would be useful to establish what model it is - CG4 or CG5? - and how many teeth are on the wormwheels. Both were clones of Vixen mounts (as are, it seems the Skywatcher EQ3 and EQ5). The GoTo version of the CG5 was superseded by the AVX. The CG4 is said to be similar in weight class to the EQ3. Going by what I have read, the CG5 GoTo was not very reliable.

I tried my smaller planetary imaging setup in order to get Venus in twilight. 127mm Mak, SLT mount, ASI462MC, filter wheel. Venus 15.7", Mars 5.7" Ther Mars image is expanded x2. The shot of Mars far exceeded my low expectations, given the smaller scope, a bouncy mount and the wind, and shows Syrtis Major, Utopia and the N. polar cap.

I suggest that you read reviews of the Svbony 105 and 205 with care. One would not expect the 105 to do much at its low price. The ZWO ASI224MC is a planetary camera which does work well for DSOs, asides from the comparatively small field of view. There are other alternatives, and if you want worthwhile results, I suggest you study these products and get a camera with an adequate performance and chip size, and be prepared to pay for it. As background, I have an old Celestron Solar System Imager camera (the cheapest in the range at the time, similarly priced to the SV105) which is not much good for anything, and a USB2 ZWO ASI120MC which works quite well for planetary imaging but is useless for DSOs (far too noisy).

I also ordered one, and considered ordering direct, but they wanted an ID number I didn't understand, so mindful of potential customs and VAT charges I decided to order via an UK distributor.

A number of mounts in this class are basically the same. If this mount is sufficiently similar to a Sky-watcher EQ-5, you can bolt on the Synscan upgrade kit (about £359) and away you go. For a little more money, you could possibly source a used EQ-5 Synscan mount, complete. If not, there are DIY routes for adding a GoTo that can be controlled from a laptop, i.e source 2x motors and build a controller board.