Cosmic Geoff

It could be anything. Is there no label on the tube that gives a clue? You don't need to know the make in order to clean it. The question is, what parts do you think need cleaning? With any telescope of this sort, shining a torch on the mirrors will highlight any dust and make them look horrible. If you do remove either of the mirrors you will need to understand about collimation in order to get it working after you reassemble. I suggest you reaearch that before you touch anything.

Anyone wanting a "scientific" record of sunspots could look on the daily SOHO site. As anyone who spends any time looking at astro images will know, the orientation of the images varies a lot. Traditionally, many are shown inverted because classic refractors show the object that way. I have also seen deep-space images that were mirror-reversed.

The make-a-finder-into-a-guidescope works best with a specific model of finder and an astro camera with the standard thread, plus an adapter ring that costs 30 to 40 Euros. Or with finder/guidescopes (sold as such) which accept 1.25" eyepieces. Otherwise you may have to to make adaptors up from stock material.

Onstep is a DIY GoTo syetem. Search this forum for 'Onstep' and you should find various threads. You should decide though whether your hobby is astrophotography or building stuff. 🙄

The Evo 8 at f10 will be tolerant of eyepieces. If you want a wider field of view, a 32mm Plossl ( or a shorter focal length eyepiece with wider FOV and higher price) will prove useful. The highest power eyepiece I regularly use in my C8 is 8mm.

If you have the budget, try using a dedicated planetary camera (+ Barlow lens) + 'lucky imaging' software. I can't remember if I tried imaging Saturn with my 127mm Maksutov, but I have tried it on Jupiter and got various shots showing the cloud belts and Great Red Spot quite clearly. Maybe it's my eyesight, but I can see a lot more on the processed images than I could visually.

The proper EQ5 kits (including handset controller) are sometimes available used, and not expensive. I assume budget is an issue here. There are actually several variants of motorizing available to you: RA only RA + Dec RA + Dec (enhanced) to facilitate guiding for imaging. D.I.Y. GoTo (various). Cheaper than the real thing but involves a lot of skilled work. Skywatcher EQ5 Synscan GoTo upgrade kit. Recommended for imaging and easy to fit. Makes your mount equal to the commercial Synscan mount. Synscan is capable of impressive aiming accuracy but needs some skill and effort to get the best out of it.

I observed this last night with my C8 and a magnification of about x250 as an easy double-double (7.9" and 11.9") Splitting the 1.1" AB would have been a tough call under these conditions. I could also just see the split of Nu Scorpii CD in the multiple Nu Scorpii system - another visual double-double (actually septuple)

Two elusive planetary nebulae in Sagittarius: I tried to image these with my CPC800, but it was a total fail. I tried again last night with my 102mm achro, ASI224MC camera, EQ5 Synscan + platesolve and resync. For some reason the NGC6537 field refused to platesolve but the target was in field anyway. The starfield around NGC6567 is exceptionally rich. I had to look at online images today to pick out the planetary nebulae. Both were low down in a hazy sky.

See this post:

I think you may be in danger of trying to run before you can walk. It also appears that you want one scope and mount to cover all bases. From your equipment list it seems you are mainly interested in imaging. There is no such thing as a telescope that can do it all. That's why I have four, and four GoTo mounts. The Star Adventurer seems mainly suited to wide angle imaging with a telephoto lens or small scope. The 6" SCT (mainly suitable for visual use) does not seem a good match for it. I suggest that rather than buying an expensive cooled camera you start with a cheaper uncooled one or a DSLR (you may have one of the latter already) and instead of the ASAIR use an existing laptop. Once you have had a go you will be better placed to judge what you really need to buy. If you intend to image with a 6" SCT you need a serious mount like a HEQ5. Check your local laws before going anywhere near a green laser pointed at the sky.

The mount looks rather like the SLT mount. I don't know how helpful this information is. I have three Nexstar alt-az mounts of varying ages and models, and several handsets (Nexstar*, Nexstar+ and Starsense). I have swapped the handsets around for various reasons and found that all the combinations worked, so the mounts are clearly not fussed about what version of handset is connected. My SLT mount works with both the Nexstar* and Nexstar+ handsets. If possible, ascertain what firmware is actually loaded in the handset and mount. Then you can figure out with the aid of nexstarsite.com whether they are actually compatible. Do not try to upgrade the firmware unless you are really sure what you are doing. I have found that the SLT mount firmware is prone to getting corrupted (giving an error 16 or 17 = no response) which can be fixed by reloading the firmware.

What kind of imaging do you want to do? I have two imaging setups, one with a 102mm achromat and the other with a 8" SCT + focal reducer. They address different field widths. If you want to capture wide (ish) fields, you want a short focal length and a small scope. If you want to capture detail on small planetary nebulae and diatant galaxies, you'll want a longer focal length and a bigger scope. The 102mm achromat is set up to plate-solve and re-sync, but that does not work so well with the SCT and its narrower field of view. You don't mention a camera - many people use a DSLR. You may already have one. Note that using an older model of DSLR can be a severe pain for various reasons. Dedicated astro cameras are easier to use but those with chip sizes comparable with a DSLR are expensive.

No, but I have a flip mirror I bought used IIRC, which has no evident branding other than 'TS'. It worked well, and has various bits which unscrew to make attachments more versatile, and the eyepiece focus can be adjusted. However I have switched away from using it, partly because the combination of this and a focal reducer and camera was too long for my SCT mount and made it impossible to image anything at medium or high altitude. The equally effective alternative is to use Precise GoTo and if necessary a right-angle finder to get the supplementary guide star centered. I also had a worrying accident when I unscrewed the camera from the flip mirror in the dark and found I had unscrewed part of the camera and nearly lost the optical window.

It is notable that views tend to differ depending on which side of the Atlantic the respondent is on. Personally I feel no need or desire to use a laser pointer. My scopes are aimed by GoTo, which means that if I am using a red dot pointer at all I am not aiming at alignment stars with extreme altitude, and I also have a right angled finder. Starsense also avoids the desire to use a laser pointer. Not trying to point the finger at anyone, but are some respondents (legally) using laser pointers that would be illegal under UK regulations?

This is the early single-arm GoTo model? Some pictures and part numbers might jog someone's memory. If the LCD on later models is the same, that raises hope that it can be sourced from somewhere as an electronic part. Is there any serial port that could be used to computer control the mount, thus bypassing the display or handset? The nuclear option is to de-mount the OTA and put it on a new mount.

You could replace the altitude T-bolt with any bolt of suitable length with the correct thread. As for the loose leg bolts, any hardware shop or car accessory store should be able to sell you a suitable spanner or adjustable wrench. You won't get an easier mount for <£40 unless you are very lucky and find one in a charity shop. There are mounts that would suit you better but they would cost you more like £200 new.

You could try obtaining a suitable external regulated +12v power supply with centre positive and plug it in and see what happens. Few people continue to use these mounts with internal batteries. One possibility is that the handset has developed a bad connection where it plugs in so you can't see it light up.

Of the suggested items, a AZ-EQ5 + 10" Newt costs around £1814, an AZ-EQ6 + 10" Newt costs £2284, and a Celestron Evo 8 costs around £1970. A CPC800 is ~ £2025. An Evo 925 is around £2449, a CPC925 £3249 A CPC1100 is £3995. Note that used SCTs seem not to hold their prices well, so can often be had for far less than the new price (as I can personally confirm 🙂) ie arounf 50%. So many C8's have been made that if you want to buy a used one you can always find one. As is widely quoted, for other astro gear it's more like 66%. The new CC scopes look good, but seem to be available as OTA only - attractively priced (in 8" size) but look like they would need a substantial mount.

I wouldn't - it is clearly designed to slew under power only. With a manual Dobsonian I was thinking I could add a setting circle and an inclinometer I tried using manual setting circles and inclimometer with a 8" Newt and EQ5 manual mount, and soon decided it was a waste of time and I wanted a used C8 SE (which cost me £650).

All the C8 OTA's are essentially the same - the only differences are the various colours and that some have a grab handle - it depends on what mount it is bundled with. (There is also the Edge HD, but that is intended for imaging as well as visual). As for the SE mount, it is on the limit, but good enough for visual use in a sheltered location, and on the plus side is portable enough for you to pick up the whole setup and carry it through a domestic doorway. The SE 6/8 mount is a little more substantial than the SE 4/5 mount, or your Synscan AZ GoTo, but I suggest you reserve it for the C8 only as you don't want to be detatching and re-attaching the fat and handle-less C8 OTA unless it's really unavoidable. It's alto the wrong shape for long OTAs. The Celestron Schmidt-Cassegrains have been in production for at least 40 years. Some people have re-mounted the really old ones and found they work as well as ever after a bit of maintenance. As I mentioned, you have a choice of bundled mounts for the C8 OTA (and Celestron also do their Schmidt-Cassegrains in larger sizes). If you have no interest in imaging, either a Schmidt-Cassegrain or a Classic Cassegrain, or a GoTo Dob should suit you.

You could have a 10" Dob Newt, but from what I've read the Goto Dobs are suited to visual only (check the imaging threads). A Newtonian on an AZ-EQ mount would work, but the mount would be a bit pricey. I have an 8" Celestron Schmidt-Cassegrain and am quite pleased with it. You can buy the Celestron C8 with a choice of bundled mounts, both Alt-AZ goto and equatorial GoTo. Or put it on any other mount you like (it's not a heavy OTA). Used, they are quite reasonably priced - half the price of new last time I checked. The SE mount is portable but a but flimsy, the Evolution is said to be better and the CPC800 package is great for visual and some kinds of imaging and solid as a rock, but a bit heavy. CC has good reports if you want a visual or planetary imaging scope, but never seen one. Apparently heavier than the Schmidt-Cassegrain of same aperture..

What do you want to do and what's your budget? Unless your object is to buy a good spotting scope with occasional astro use, I would recommend avoiding the 'One scope does all' solution and buy 1 spotting scope and 1 astro scope with your budget. BTW, if you buy a Startravel 102mm widefield achro telescope for around £200, it comes with a terrestial 45 deg erecting prism and 2 eyepieces, so as well as its (widefield) astro uses, it could be used as a spotting scope (though not the best-ever spotting scope regardless of expense). Also needs a mount. For a satisfactory view of Saturn or Jupiter (rather than seen the rings and belts, sort of) a fairly high magnification is required. Some spotting scopes will zoom, but zoom telescopes and eyepieces have some undesirable issues.

You don't explain how you are taking the image. If you are using a planetary camera, the capture software should have a histogram tool or suchlike to tell you if the image is correctly exposed. If you have live view, adjust the exposure till you can see the cloud belts.

The thumbscrew for an EQ-5 5Kg weight has a thread of 8mm diameter, but only the outer 20mm is threaded. The end of the screw is plain and thinner (and the inner part of the hole appears smaller). If you copy this, it should be easier to make, and you are less likely to break off your tap in the hole if you are only threading the first 20mm or so.