Cosmic Geoff

I have used a similar setup, and I was able to flip between the ASI224MC (in focus) and 25mm eyepiece (roughly in focus) with the camera screwed directly to the mirror box via the T-thread adaptor. TBH I have never bothered my head about "back focus". Unless the camera is a) in focus and b) accurately aimed at Jupiter, i.e dead center* in the eyepiece, you won't pick up a thing. The camera field is much smaller than the eyepiece field even if you select the full chip as the ROI. I suggest dispensing with the flip mirror as you should not need it for locating in-your-face bright objects like Jupiter. * or maybe offset by a small amount depending on the mirror setup.

Been there, had that experience. Read my earlier post. You will not get anything unless the camera is almost in focus.

If you want a quick and comprehensive answer, I suggest you read the other threads here generated in answer to similar queries. As for you will need to define what you mean. There is nothing in a £150 telescope outfit that will connect to a phone, unless you mean using the phone as a camera to take snaps through the eyepiece.

You may get various suggestions about the finder. A straight-thru optical finder will prove a pain in the neck (literally). A 9x50 right angle or corrected-image right angle finder (RACI) plus a red-dot finder is a good combination. You could add another bracket, or get an adapter to mount both on the same bracket.

Forget the Celestron wedge. Your 8SE outfit is primarily intended as a (portable) visual scope. It can also be used for planetary imaging with its alt-az mount, but it is better to use a dedicated planetary imaging astro camera. With patience, it is possible to get good results. The mount is really not suitable for long exposure deep space imaging. It is possible to re-mount the optical tube on an equatorial mount (at considerable expense) and use it for deep-space imaging of smaller objects, but this is not really an exercise for beginners. The consensus among people who have actually tried imaging with a wedge is that it is a bad idea, and it is better to use an equatorial mount, which gives a superior performance and is easier to polar align.

You have not specified what size of scope you are using, or the camera, or the size of the captured video, or the programs used to stack and sharpen. If you are asking for feedback, it helps to give as much detail as possible. I have not double-checked by comparing your image with one of my recent shots, but have you corrected for the L-R swap introduced by a star diagonal? (You can easily correct this by ticking a box in Registax.) Overall, your image is not bad and shows a lot of surface detail. As for the fringing, there is an effect that occurs when trying to process Mars images. it is common enough to have acquired the name of "rind", and is an artificial brightening of the fully illuminated limb of the planet. It seems to occur with over-sharpening.

I have found that with the similar EQ5 Synscan that inaccurate GoTo is all too common. If you want a more accurate GoTo, you need to select alignment stars on the same side of the sky as the object you want to observe, and with one of them not too far from it. Or use platesolving. I routinely find that platesolving corrects the aim by 0.3, 0.5 or 0.7 degrees.

I have a 102mm Skywatcher Startravel, and agree that the performance is not great. But this is a f5 achromat, and if you think its performance is typical of what you would see with a f10 achromat, you are entirely missing the point. A chart has been posted more than once on this forum showing the colour correction performance of achromatic telescopes according to focal ratio and aperture. Large apertures with short focal ratio are dire, while small apertures and long focal ratio are very acceptable. I own a vintage 70mm achromat refractor with a very long focal ratio and the colour correction is entirely adequate, and the overall performance is superb. On the other hand, it is rather long and heavy. 🙂 You clearly appreciate the quality of premium priced kit. But will your family appreciate the difference when looking through they eyepiece? I doubt it.

If you want a 4" refractor for visual use, there is no need to spend that much money. For centuries, amateurs were entirely happy with achromatic refractors of long focal ratio. A present-day example is here: Sky-Watcher Evostar 102 (EQ3-2) | First Light Optics Recently the various ED scopes have appeared, which offer a potentially better colour correction in a shorter tube, at a substantially higher price. The combination of a short focal ratio and good colour correction is particularly relevant to deep-space astrophotography. Not so much for visual use. If you want to spend your money on an expensive premium scope, that's up to you, but if you are willing to spend £2000 there are plenty other options with bigger aperture and features like GoTo.

Good effort with a 70mm refractor.

If one likes an 8" Dobsonian, that's fine. But if you decide it's not for you, the options (at the same aperture) are to go for an equatorial mount, with the pluses of potential use for imaging, having GoTo, and the minuses of increased cost, weight and complication. Or go for an 8" SCT, with a much lighter OTA and the potential for having a lightweight GoTo mount in a portable visual setup, or an equatorial mount with potential for imaging. Or on a heavy duty fork mount if that takes your fancy.

Here is one of my best results on Mars, taken at 22.40 UT on 8 Nov. 8" SCT, ASI224MC, IR-cut filter, ADC, Sharpcap 5000 frame video. Processed with Autostakkert, Registax, Photoshop Elements. Diameter=15.9", so almost at maximum dia for this opposition.

No replies yet? One would expect collimation to be more critical than with a f6 Newtonian. But does it go out of collimation? Is there even a collimation adjustment? Are the cheap eyepieces good enough to give the best performance? A f4 Newtonian would normally demand some rather expensive eyepieces.

As you can see from my signature, I have some equipment similar to yours. I would suggest that you get a tri-pier (a semi-portable pier with three feet) and park it in a suitable part of your garden, put the EQ-5 Synscan mount head on it, polar align it, and leave it permanently in position. Sky-Watcher Pillar Mount | First Light Optics You will need a waterproof cover. Then after a session you can 'park' the mount, power off, remove the scope and cover the mount. At next session, attach the scope, power up, un-park, and you are ready to go - no polar aligning or GoTo aligning needed. I use the mount mainly for EEVA (q.v.) style imaging, and plate-solve to confirm the targets.

I have a C8 SE with the same style of finder. Sorry I can't offer any further advice. I assume you have tightened the two long bolts that pass through the 2 inch long clamp under the finder body? My finder is fairly rigid for what it is. Is there any way you can get someone familiar with these finders to take a look at it? If you want to replace the whole thing, I recommend the Baader SkySurfer III finder. I have had three of the basic red dot finders like the one in your photo and they all started acting up after a while and refusing to light up the red dot.

This is a common request. I suggest you read the replies here made to similar queries, and come back if you need an answer to a more specific question. £100-£250 seems too low for a tracking mount. Either simplify your requirements or be prepared to spend a lot more money.

A dew shield is an essential accessory for a SCT, not an optional extra. A dew heater may be additionally needed in severe cases. (I don't use dew heaters myself). I have recently learned that Celestron supply a heater ring that replaces the corrector plate retaining ring and gives a neater solution than using a heater band.

Yes, they do have small sensors, and the FOV is small. Acquiring the target is a skill you just have to master. One way of doing it is to center the planet in an eyepiece (it does not have to be in focus) and then swapping in the camera. Another way is to use a good quality optical finder to get the planet on the sensor. The capture software should be set to acquire all the pixels when finding the planet - you can reduce the ROI (region of interest) to e.g. 320x240 pixels once the planet is centered.

A voucher or cheque would be the safest option. If you are determined that it be a surprise, I suggest a classic long-focus achromatic refractor on an alt-azimuth manual mount. Some people are in love with these traditional scopes, so your husband is unlikely to dislike it. Aim to spend at the upper end of your budget. Something like this, but maybe with the longer Evostar 90 OTA. Sky-Watcher Evostar-90/660 AZ Pronto | First Light Optics

Replace the 10mm eyepiece with a decent one. Plenty advice here on eyepiece choice. 🙂 And make, or buy, a dew shield. That's essential equipment for a Mak.

I suggest that you not bother buying any more accessories for this telescope. The mount is not adequate for any sort of imaging. I suggest that if you are interested in imaging, you do some research on what is actually entailed. Reading the forums here would be a good start. Astro imaging is a very expensive hobby. You can certainly re-mount the scope, but I don't think you will find the suggestion of an EQ-5 Synscan at around £700 amusing. I suggest you enjoy the scope as it is, and consider buying a better beginner's scope in the course of time. There is plenty of advice about buying a beginner scope here.

Eyepiece position is not really an issue with small alt-azimuth mounted telescopes. But you should factor in the use of some kind of stool to stabilise your body position and aid reaching the eyepiece. Standing to observe is not really practical for serious observing. I do not use WiFi and am happy using the plain old handset. In my opinion the Celestron Nexstar GoTo software is a little easier to use than the Skywatcher Synscan. If you want to image anything, you will probably need to (expensively) re-mount your chosen telescope, though you might get away with using the mount it comes with for some planetary imaging.

Get it repaired. There are various threads here on this or similar issues. Much cheaper than buying an EQ6. Is a flex-tube suitable for single-sided attachment?

A 'digital eyepiece' is a digital camera - generally a cheap one, it appears. I think you will find such a device disappointing. The main issue is that the sensor chip is generally small - similar in size to the field of a 5mm focal length eyepiece - and this is unlikely to give you the eyepiece replacement effect you may have in mind. You can try it for yourself, as these devices seem inexpensive, but your money might be better spent on an eyepiece upgrade. The eyepieces supplied with telescope outfits are usually poor.

The AZ-4 might do (7 Kg max). I suggest though that you get an EQ-5. get it set up and mark where the tripod feet go. Then next time you use it, just take it out and put it down on the marks. Good enough for visual. As you say, you can upgrade this mount later to motorised (or GoTo).