Cosmic Geoff

Physically exactly the same, but the firmware may not be the same. With any luck it will at least demonstrate that your SLT handset is at fault, and it may work fully. If anything weird happens, you may have to do a bit of research to get the full picture, i.e which firmware serves which group of mounts. When I flashed my SLT firmware a couple of years ago, I think there were just two options, one being the wrong one... Was it alt-az and EQ? I found that my C8 SE seemed to work with its original Nexstar handset, with the Nexstar+ handset from the SLT, and a Starsense, without having to reprogram anything.

If the handset was OK and the mount faulty, you probably would get an Error 16 or Error 17 (horizontal or vertical drive circuit not responding). There is not much in the base besides the horizontal and vertical drive circuits. You might care to unplug one of these drive circuits and see if it makes any difference on the display. If you buy a handset and then decide to upgrade the scope, you would get more for the SLT working than as spares/scrap, so you could recover the cost of the repair. Your OTA would definitely sell. At minimum, it seems you are going to have to pay the cost of a handset to get a repaired scope outfit (and a lot more if you upgrade).

I am not familiar with this camera, but an ASI224 planetary camera will record a 1st magnitude star in about 1ms with an 8" telescope. If you focus on "leaves" then stars at infinity may be sufficiently blurred that they fail to show.

I did not read the original post very carefully. ☹️ Seems like the OP did all he reasonably could to check out the fault, which is probably a faulty handset. If the OP acts quickly, there is a Nexstar+ handset for sale for 50 pounds in the For Sale section of this forum.

You may make some progress with your existing equipment, but equally I suspect that a different scope, a dedicated planetary video camera, and a Windows laptop (or dual boot on your Mac) would improve matters. See the images taken with a 127mm Maksutov in the Planetary Imaging thread.

You may have trouble getting an ADC to work with a PDS Newtonian, as it adds several centimetres to the light path. Which is why I suggested using a SCT. I got a used C8 + SE mount for £650. You might get an OTA for even less.

What is the issue with the handset/mount? Mine gave an error a couple of times, and I fixed it by re-loading the mount firmware AFAIR. A bit of a faff, but did not cost me anything other than for the cable and serial/USB interface. The 8 SE - stability for what? It is at the limit with the C8 OTA, but is still perfectly usable as a visual scope, especially if you keep the tripod legs retracted. If you want it purely for visual use, don't let the stability issue deter you. If you have put up with the 127mm Mak on the SLT mount, you should not find the stability of the C8 SE an issue. You cannot just buy the Starsense handset - it is part of a handset/camera package costing £300, and without the camera it just gives a startup error. It is possible to buy the Nexstar+ handset if that is definitely the problem, and not the handset or mount firmware or other cause. I recommend that you get the mount properly diagnosed before doing anything else. You may find www.nexstarsite.com helpful.

Read the AZ-GTI manual.

I suggest you check the 'Planetary Imaging' section of the forum to see what gear others have been using. It's not impossible to image with a Dob (and it's not impossible to cross the Atlantic in 🙂a rowboat. ) But the best tool for the job is a SCT of aperture 8" or greater. The depth of focus makes it easy to attach imaging accessories - cameras, atmospheric dispersion corrector, flip mirror, filters. As for the mount, either an alt-azimuth or a equatorial mount will serve, but it makes the task a lot easier if the mount is rigid, tracks, and has a minimum of backlash. Without accurate tracking, a planet will go out of a 320x240 pixel ROI very quickly. The CPC800, for instance ticks all the boxes with its substantial fork mount, mimimum backlash, and GoTo but unless you get a great second-hand deal may cost more than you want to spend. I also tried using a C8 on a EQ-5 Pro Synscan mount, but by comparison with the CPC800, the amount of backlash was quite annoying, and the potential for a 'meridian flip' when working near meridian transit equally annoying. And you need a good finderscope - just getting a planet onto a small camera chip is a challenge in itself.

I have the impression that some higher priced scope outfits may be difficult for private sellers to shift second-hand. I bought an expensive scope outfit in as-new condition for half the new price AND it came with a boxfull of valuable accessories.

The choice of alt-az GoTo mounts that will handle a 6" or 8" Newtonian is very limited. I am only aware of the Sky-watcher AZ-EQ5 or an Ioptron model. These both cost so much that you might as well look at an 8" or 6" SCT on an alt-az GoTo mount. In fact I bought my used C8 SE for less than the price of either of these mounts. You could also look at Dobsonians with GoTo. They are alt-az...

Without looking up the details, I recall there is a known error in the instructions, and that at the relevant stage you have to press ALIGN instead of ENTER.

Also, if you live near the equator, I think I am correct in saying that putting the CPC1100 on a wedge would entail laying the mount almost on its side, which could place an excessive strain on the bearings.

The TEMPest fans are presumably designed to circulate air through the tube so that the optics cool down to ambient temperature more quickly and achieve best performance sooner. Before buying them, you should carefully check the specification of the EDGE HD 1100 to see if it doesn't already include equivalent fans. Re the wedge, first explain why you want to put the scope on a wedge. This will convert the mount to a fork equatorial mount, which would only be required for long exposure imaging of deep space objects. Despite what the manufacturers and retailers may say, feedback from users of these scopes is that after trying the wedge for these purposes many of them give up and buy a German equatorial mount and a different telescope for the purpose. If this is indeed your aim, I suggest the additional purchase of an EQ-6 Sky-watcher mount and a small aperture short focal length apochromatic telescope, and the book "Making Every Photon Count."

If it won't focus even with a Barlow,, you need to get a different scope designed to accept cameras, or modify your scope.

Not good then; the mount in my profile pic was an EQ-2 clone. You could try an EQ-2 motor kit if you think it's worth the expense and confirm it's the same mount.

If your mount is the same as the Sky-watcher EQ3-2, then there are several motor kits that would fit, including a GoTo.

If you bought a RA motor for your existing mount, you would be able to perform stacked imaging of the Moon and planets. That would be a sensible next step. I don't know anything about the EXOS-2 - it seems not to be a commonly purchased mount.

With most cameras you need to place it further in than with the typical eyepiece. (as much as half an inch closer) With some telescopes this may not be possible without modifications. A Barlow lens may allow you to get focus in this case.

You seem to be comparing a dollar priced scope with a pound priced scope. My own research some years ago indicated that push-to and go-to scopes cost about the same. Even though GOTo have motors and push-to do not, from a manufacturing point of view, they contain the same amount of "stuff". That said, the XT8i looks like a good price - in the USA anyway... To import to the UK, you will have to pay shipping and import duties. The Sky-watcher Dob GoTo costs about the same as a 8' Newtonian on a German equatorial GoTo mount. I suggest you look at other options/makers. Is this purely for visual use?

The image moves when I adjust the levers in my ZWO ADC. Nothing to do with the atmosphere affecting the apparent height - it's something to do with the prisms. Which side do the levers go on? Whichever way gets rid of the colour dispersion.

There are two stages of alignment, centering in the finderscope (or maybe the eyepiece), terminated by pressing ENTER, which automatically changes the slew speed to a slow speed (no, the arrow buttons do not stop working, but it may look like it in the finderscope), and the fine align in the eyepiece, terminated by pressing ALIGN. That's what happens with my Nexstar handsets.

I use the ZWO ADC which makes a marked difference with the levers set suitably. It's not a clone of the Altair so I can't help you with that one.

I tried imaging the same event with a C8, ASI224MC, ADC. The seeing did not look great, and the results, processed in Registax6, (best 20% of 5000 frames) were so poor I am deleting most of them. They look worse than images made a few days ago with my smaller 127mm Mak. I don't think it was a focus problem as I focused on a star, Altair. In previous seasons I have found the results with the C8 imaging very variable - I assume due to the seeing. I am imaging from a town with built-up area for at least a mile to the south. What is the terrain like at your location?

Did you read all of this thread? https://stargazerslounge.com/topic/272708-wedge-for-nexstar-se-68/ Having used a C8 SE for planetary imaging and put up with its wobble and backlash for a season, I think that the idea of putting it on a wedge and trying more ambitious forms of imaging with it is a bad joke.