Cosmic Geoff

Looks like a de-bayering issue to me too.  Next time, save the file in .ser format and you will not have to de-bayer it.

Another Mars image ... in this one I have managed to record Olympus Mons which did not show in earlier images I made of the same longitude.  The seeing seemed good, but the sky was hazy and cloud-free as I set up. By the time I was ready to image, some cloud had come over, and instead of clearing it developed into 100% cover and an unexpected heavy shower.  As I was dismantling the now very wet telescope the sky cleared again offering a tempting view of Mars so I put all the bits back, aligned on Mars and took a series of videos.

Kit: CPC800, ASI224MC, ADC.   20% of 5000 fromes, processed in Registax6.  I also tried a x2 Barlow but those images did not turn out well - looked out of focus.

You mean, is it a 10-second swap or does it require some engineering?

If you post some pictures of how the 'scope is fixed to the mount, we might be able to tell you. Many scopes and mounts use a standard dovetail clamp. 

If you know what latitude the mount was set for, it should not be a problem to stick the scale back on.  The scale on my EQ5 does not seem to be aligned accurately anyway - it's really just a guide prior to doing a polar align.

If you have no idea what latitude it was set for, why not polar align it the next clear night and then stick the scale on?  You probably can't zero the scale as it is not meant to be used at 90 deg or 0 deg latitude.

If it helps, the alt-azimuth Nexstar  GoTo mount bundled with the C6 is one of the easier GoTo systems to master and use (I also have a EQ5 Synscan).  I don't like the Synscan system.

If you look, you will find several alternative bundles incorporating the C6 OTA.  There was one deal which effectively threw in a free GoTo mount. Others included an nice Evolution alt-az GoTo, and there is one with an AVX German equatorial.   The cheapest ones might prove too wobbly, but the C6 SE has the same mount as the C8 SE.

Whether you want the convenience of GoTo and actually being able to find stuff, or the simplicity of a Dob (apparently it can be used without the GoTo) is entirely your choice.  As with the C8 SE, the assembly of C6 SE tripod/mount/OTA is light and compact enough to be carried out through a standard door in one lump.

As for reliability and quality, the Celestron SCTs are well made and the design has been popular for the last four decades.  Electronic gear does eventually tend to fail, but in this case a likely scenario is that you would take the opportunity to upgrade the mount with a new and better design, retaining the same OTA.   My C8 SE mount is several years old, and still working.  The electronic engine control system in my car is still working after nearly 20 years.

I have never seen M33 (or M1), despite looking for them on occasions. I think that very dark skies are needed. 

I managed to get faint images of them with my EEVA setup, which underlined the difficulty of seeing them visually.

1 hour ago, Neil H said:

If levelling is not important  why does the manual tell you to level the mount using a spirit level

Probably because it makes for simpler instructions.  As discussed above, the alt-az mount does need to be accurately leveled for a 1-point (1-star or solar system) alignment, but as various people have found, not for multi- point alignments.

The alt-azimuth Nexstar and equatorial Sky-watcher Synscan systems differ significantly, so cross-comparisons are not necessarily valid.

Leveling the mount is only critical if you are relying on a one-star or planetary align.  Otherwise you can get away with the mount just looking level, eg if you have set up on concrete that is supposed to be flat.  The C8 SE can be carried out in one lump, which is a reason for not taking the assembly apart to accurately level it. 🙂

With the Celestron SE mount, to level it you are meant to set the little bubble level on the machined top surface of the tripod (the only true flat surfact in the outfit), which admittedly is a bit of a faff.  I'd do this only  if setting up on uneven ground or if intending to use the solar system align.

With your £2000 you could buy some quite useful kit, but I would suggest that you first buy a relatively inexpensive outfit to see how you get on.  There is unfortunately no all-rounder scope that does everything, especially if you want to do imaging.

An 80mm aperture apochromatic refractor  on an EQ-6 mount would be a fine setup for deep-space imaging, but not much good for general observing or planetary imaging.  I'm told that deep-space imaging is an expensive and very demanding hobby.

A CPC800 would be fine for planetary imaging (with a specialist planetary camera, not a DSLR) and general observing, but not good for deep-space imaging.

Various outfits such as a 8" Dobsonian or a Celestron C8 SE would be fine for visual observing but not much good for imaging anything.

No doubt someone will suggest an outfit that comes closer to meeting your requirements. 

I should also point out that an alt-azimuth GoTo mount (primarily suited for visual observing and planetary imaging) is generally much quicker and easier to set up than a German equatorial GoTo (required for deep space imaging and not much else).

I would suggest that if you are determined to 'dive in at the deep end' that you think in terms of 1 mount + 2 different scopes, or 2 mounts and 2 scopes, rather than trying to find a compromise. 

I have used a ZWO ASI120MC with good results. The ASI120MC-S should be more or less in your budget, or look for a second hand one.

First advice - do not unclamp the OTA from the mount. I never liked doing this and until I fixed a handle on the side of the tube only ever did it over a carpet with the mount detached from the tripod. It is hard to get a grip on a 9" dia OTA that does not have a handle!

AFAIK you are expected to keep the mount head and OTA as a unit, and unscrew the mount from the tripod if you have to.  If you keep the legs retracted, it is possible to pick up the whole assembly and carry it through a standard doorway.

The mount should track just fine if you get all the GoTo setup right (lat/long, timezone, date format, DST) and remember to complete the procedure by pressing Align (otherwise it will not track).  GoTo tracking can be very good - i.e. keep an object in low-power field for hours.  There are three menu options for tracking rate (siderial, lunar and solar IIRC).   IIRC the date should be in USA format.

You need a proper external +12v supply and a good plug connection, otherwise the mount may misbehave.

Out of focus objects always have a black hole in the middle with these SCTs (because of the central obstruction).  If it does not look symmetrical, check the collimation.

6 hours ago, Hoopla said:

thanks for the advice. I assume the EQ3 Pro can track Mars though or am I wishful thinking? 

You have the Eq3 pro Synscan? If you set it up properly, it will track Mars as well as the starry sky. All GoTo mounts will track planets once set up. The default siderial rate will track Mars. Yes, Mars does move across the sky, but not fast enough to matter in an hour or two.

Imaging planets is something of an art.  You can get an image with your telescope, but you need a Barlow lens to increase the image scale, and a camera capable of taking a video. A single shot is guaranteed to look distorted and blurry, because of the 'seeing'. You can try using a DSLR, but it is better to use a dedicated planetary camera, capable of taking several thousand frames of video at up to 200 frames/sec, and with a cropped region-of-interest to speed things up and save on storage. And then process the result.  With good seeing you should be able to get a decent result.  Have a look in the Planetary Imaging thread here to see what others have achieved (and with what kit).

You also need a mount that will at least track, but it seems you have that.  And a good RACI finder to re-find Mars should it wander out of shot.

13 hours ago, Spacecake2 said:

Do you mean Nextar 8SE?

This:

https://www.firstlightoptics.com/se-series/celestron-nexstar-8se.html

What does OSC stand for? From the context is seems to mean 'colour' so why not just say 'colour'?

I Googled the meaning of OSC and found it could have over 120 possible meanings. 

There is no 'should' here. If you want better performance, buying a bigger scope will do what you want.  I would suggest a Celestron C8 SE as the next step up. Unless the seeing at your location is consistently bad, the C8 will give better performance, both visually and with a planetary imaging camera.

Seeing in the UK has a large influence, and there have been nights when I took better images with my 127mm Mak than with the C8.  If the seeing is really good (usually outside the UK) it is worth using apertures of 14" or more.

If cost is an issue, note that SCTs are often available used at a large discount on the new price. 

11 minutes ago, rnobleeddy said:

Thanks. Does that apply to using a DSLR to record video? In either case, it makes sense to use the zwo with a 1.25" Barlow.

The thinking for the scope was a longer focal length would be better. I've recently got an EQ6 so should be ok for something bigger, but I expect I'll always be more interested in DSOs, and afaik, there's nothing that can be good at both?

With DSLRs, recording video is an afterthought, while recording high-speed video is the whole point of a planetary camera.

Planetary imaging - best with big SCT.

Deep space imaging - small high quality refractor (or a 130PDS) recommended.

16 hours ago, Shepdog said:

What about an actual camera? Like they use for full blown astrophotos?

You mean a DSLR?

The reasons people use a DSLR for astrophotography are twofold - a lot of people already own one, and if you want/need a large sensor with lots of pixels, it is usually much cheaper to buy it as part of a DSLR than as a dedicated astronomy camera.

If you actually try it yourself, you will find that using a purpose made planetary camera is quite straightforward, while operating a DSLR in the dark, where you can't see the controls, can't see if it is in focus or if the exposure is correct can be a right pain.  A DSLR sensor is bigger, and often with bigger pixels, than you want for planetary imaging.  If your telescope & mount will not take the weight of a DSLR that just indicates your setup is not suitable for imaging.  For any sort of imaging you want a very solid mount that at least tracks.

I would not. The eye relief will be small and it is too powerful for the telescope.  The quality will be OK, and anyway a Mak with its long focal ratio is not demanding of eyepieces. An 8mm eyepiece would be more suitable.

You should use the ASI120MC and the 2x barlow.  There is no point in using a DSLR for planetary imaging unless it is the only camera available. You do not need a large sensor for imaging a small dot.  As you say, it would be as well to have an x3 barlow (for use when conditions are good and to increase the image scale.)

If you want a better OTA, that means a bigger or longer Newtonian (which will probably overload your mount) or a 6" or 8" SCT (which will probably overload your budget).

56 minutes ago, Quicky said:

Any recommendations for one under 100 quid??

If you are feeling lucky, check: "T7C ST4Guide Star Planetary Telescope Electronic Eyepiece Camera High Speed CMT"  on Ebay at £73.46.  This seems to be the Datyson T7C camera, supposedly a cheaper clone of the ASI120MC (USB2) which is now replaced by the ASI120C-S (USB3).

One of our forum menbers bought the Datyson T7C and thought it worked okay.

A decent planetary imaging camera costs several hundred pounds.  The first one I bought cost a lot more than this one you cite and it was still pants. You get what you pay for.

23 minutes ago, Floater said:

Welcome to the forum ... and harsh reality!

Personally I found telescopic views of the planets a little disappointing.  In the end I turned to planetary imaging, which on most occasions showed me a lot more detail.  Maybe I am not a skilled visual observer, but with my 127 mm Mak I mostly could not make out Jupiter's Great Red Spot, yet when I imaged Jupiter with the same scope the image clearly showed the size, colour and shape of the GRS.

Currently I could make out some surface detail on Mars visually with a C8 SE but my images showed more.

I am not convinced by the notion of a 'good all round' scope.  Designs vary so much that the result is usually more suitable for one function or another.  In the interests of transparency, I should reveal that the outfit the dealer was 'pushing' on you is the very same model I nearly bought to take home some years ago, but did not because it was out of stock at that store.

Re that dealer recommended outfit: almost nobody ever complains of buying a bad Maksutov.

Mak - good buy.

102mm - fine if you wanted a small, compact, portable instrument.  A bit on the small side for planets or some deep space objects like galaxies.

GoTo - good if you want to be looking at objects rather than for them, and don't mind having to deal with an electronic mount.  It is particularly useful if you live in an urban area.

f10 (or longer?) focal ratio - makes it good for objects requiring some magnification, e.g.  double stars and planets.   Not so great if you want to look at extended objects, eg the brighter and more famous open clusters.

If you see a contradiction above re. planets, well, right. They can look underwhelming when seen through a smaller telescope. 

Unless you are in the fortunate position of being able to try out several instruments before purchase, your first scope becomes part of an exercise of figuring out what your main interests are and what kind of scope you want to buy next.

If you want to take pictures but do not want to make the effort of mastering imaging techniques, have a look into EEVA - taking images that are viewed at the telescope.  See the sub-section in this forum.  I have used a 102mm f5 refractor with a ZWO ASI224MC camera and Celestron SLT alt-az GoTo mount mounted on a wooden tripod for some EEVA. I managed to do some interesting things with it,  taking images that plainly included Pluto, imaging various comets, globular clusters,  and Messier objects M1 and M33.  Some of these objects could not be seen visually with any of my telescopes.

Note that this gear list is not a 'recommended' list - I had all that gear on hand anyway.

Dobsonians are not really suited for imaging. Sure, people have taken images with them, but you can also row across the Channel if you really try. Most people prefer the ferry. 🙂