Cosmic Geoff

4 hours ago, chris2 said:

eqpt EXPLORER-200PDS (EQ5)

I used to have a 8" Newtonian mounted on an EQ-5.  Given the size and top weight I think you would be better advised to move (carry) the OTA and mount separately.  The two sections will also store in much less space.

If you can't resolve the problem I suggest just not using the Starsense and GPS together. It won't be a great loss.  If you hook up the GPS alone it will correct your location. Then use the Starsense alone till you change location. You will have to enter the time and date...

I have Starsense fitted on my C8 SE.  I  still have to enter time/date/location, but it eliminates a lot of annoying alignment activity each time I set up the telescope. The final result does not seem to be any more accuurate than a 2-star align.  On the other hand, the handset has some very handy menus for classes of deep sky object, arranged in order of brightness.  Whether you think this is worth £300 is entirely up to you.

BTW, you can store the settings and use the Starsense with up to 2 other scopes.

I have GPS on another Nexstar scope, which eliminates all the annoying setting of time/date/location, so I just have to do a 2-star align.

The C8 is a classic scope that has been in production for many years.  Apparently some of the older ones were great and some years manufacture not so great (rather like wine vintages).  Depends where they were manufactured and to what standards of QC (earlier ones USA made, later ones China).  The C8 is a great scope for visual observing. There are some articles online if you search.

As for astrophotography, people do use them for imaging (small) galaxies, but this is not easy and not for novices.  The C8 is really better suited for planetary imaging.

As for the mount (if any), if it comes with an antique mount you will probably want to replace that with a modern GoTo mount, and this should be reflected in the price you pay.

The red dot finder is not great, but as your scope has GoTo you only need to use it at the beginning of your session. 

If you want to change it to an optical finder there is planty of choice, but you may have to do a bit of work to figure out how to attach it to the 6SE tube.  If you don't get a Celestron finder that has a shoe that bolts straight on, you should still be able to find a shoe that will attach to two of the screw positions on the rear casing and accept a Sky-watcher finder.

Don't be put off Celestron as a brand by your experience with one of their cheap offerings - their more expensive offerings are fine instruments. Their 8" SCT is a classic that has been popular for many years.

From what I have heard, the AZ3 is not a good mount and it is difficult to make the telescope stay where you want it as it tends to tip forwards or backwards being pivoted from underneath.  You should be able to find a better one among the more recently introduced mounts, e.g. the AZ5.

Beginners should avoid EQ mounts as they generate confusion without offering any marked advantage, and the cheap ones are wobbly and of poor quality.

The 'mini-Dob' Newtonian reflectors have a decided advantage in that the bulk of your money is invested in the optics rather than half of the money going to a cheap wobbly mount and tripod.  The problem of what to stand the 'mini-Dob' on is easily solvable (an old table?)

Whether you get a refractor or a reflector is really a personal choice, but in larger sizes the reflectors are cheaper and lighter.   I recommend that you choose your next telescope purely for visual use and don't consider astrophotography at this stage. By all means attach your smartphone and see what you get.  Beginners tend to totally underestimate the level of equipment, skill and costs required to make a proper job of astrophotography.   The requirements for photographing planets and photographing deep space objects like nebulae are different and neither is cheap.    The typical setup for imaging deep space objects using long exposures is a small high quality (apochromatic) refractor mounted on a heavy duty GoTo equatorial mount, plus a DSLR camera, and this typically costs well over £1000.  The book "Make Every Photon Count" is an essential reference.

The other route into imaging is to take wider field images with a DSLR camera mounted directly on a small equatorial GoTo mount.

Not a leading battery brand, but otherwise should be OK.

What are the faintest magnitude stars you can see with the unaided eye on a decent night? If you are looking out over fields the conditions should not be too bad.

Deep sky objects never look very exciting visually - the typical galaxy appears as a faint fuzzy grey blob. The Skywatcher Skyliner 200p is a popular recommendation for beginners as it ticks several boxes - a lot of aperture for the money, simple to operate, quick to set up.  And star clusters should look great through it. A cautionary note - to see faint deep sky objects you first have to find them, and without the 21st century assistance of a GoTo mount this is easier said than done. I used to own an 8" Newtonian on a non-GoTo mount and finding anything other than planets and similar easy to locate objects was a near total fail.

From my edge of town location I can see some brighter galaxies with my 8" SCT.

I own the 127mm Mak SLT and also a larger SE.

The SLT mount is pretty light weight and basic and not suited to anything other than visual observation.  I still use the Mak (yes!) and sometimes the SLT mount on a wooden tripod but have not put together the  original setup for ages.  This mount will be no better with the 5 SCT or 6 SCT mounted on it.

If you can afford the 5SE or 6SE you get a more substantial mount.  The 6SE mount is the same as supplied with the C8 SE and is an adequate mount for visual use and a bit of planetary imaging etc (though for serious imaging you would want a better mount).

You can also buy the C5 and C6 on an AVX German equatorial, and the C6 on an Evolution mount at interesting prices.  Somwthing seems implied here about the quality of the OTA and the adequacy of the SLT mount...

Colour filters are of marginal usefulness, so no need to rush out and buy any.

I have a Baader OIII 10nm filter which makes emission nebulae like M27 easier to see by passing their emission bands.  It makes anything else look dim and green.

In general one cannot see any colour on faint deep sky objects.

I have done firmware updates, but I would prefer to refer you to the instructions on Nexstarsite. I have not tried doing updates with Windows 10.

You do need to sort out the driver for the serial/USB adapter, but I don't see why you are having to pay for a driver. I found a free one.

Unless you need to update to fix a known documented issue, if the mount is working, I recommend that you just leave well alone.

Your problem is likely to be either user data error, or a poor connection at the power input socket. I have had my Nexstars play up because of poor power plug connctions on a number of occasions. The cure is twofold: use a sharp craft knife to slghtly splay out the split 2.1mm centre pin for a better contact.  And fix a cable tie next to the socket and lead the power cable through it.  This will relieve any strain and twisting at the socket as the mount moves around.

I doubt very much that updating the firmware will cure your problem, even if the mount is old.  You can look up and read the small print that tells you what issues these updates are meant to fix. Does it say anything about the scope heading in the wrong direction?

I have the Celestron 127mm Mak which is much the same.  This scope is a 'keeper', and well suited for viewing the planets, Moon and other small objects. Compact, but big enough to be useful. Nobody has ever complained about buying a bad Mak.

Wouldn't a CPC 800 be smaller to store than an equivalent 8" SCT on an EQ mount such as an AVX?

Not significantly, I think. The folded tripods will take up much the same footprint and the OTA would be easy to store once taken of the AVX mount.  And if you are going to move the CPC800 any distance, you may want to use a trolley.

Talking Celestron, the cheapest 8" SCT is the C8 SE.  This is a compact and lightweight package, and I can pick up my assembly and carry it outdoors. Be aware this is a visual scope. If you try to do any kind of imaging with it, you are likely to find there is too much vibration, too much backlash and it's generally a pain. But if you are determined, you can do planetary imaging.

Avoid anything to do with wedges. I have not used one, but from what I have read it is hard to do polar alignment and if you want to do that sort of thing, you should have bought a German equatorial in the first place.

You can buy a C8 bundled with an equatorial mount (AVX).  Probably a good setup for general imaging.

The CPC800 comes with a substantial fork mount, and build-in GPS.  It's a great scope for visual, and planetary imaging and suchlike, and with the alt-az mount and GPS, setup is really easy.  It is extremely stable.  But be aware that the OTA/fork assembly is seriously heavy at around 20KG.

An optical variant is the EDGE HD, which have a corrector to give sharper images to the edge of the (photographic) field.  Not necessary if you want to view or image small objects that don't fill the FOV. And check the price of focal reducers...

Another mount variant - the Evolution - is a better engineered version of the SE format. It has extra features including built-in wifi. Seem to use same tripods as SE though.

All these use the Nexstar software which I have always found easy to use. It features Solar System alignment - a useful feature which some other popular brands don't have.

I hope this helps.

I have taken many pictures of Jupiter, so here is some blunt advice.

The C8 SE is a visual scope. You can use it for imaging Jupiter, but it will be a bit of a pain - mount not rigid enough, too much backlash, etc.  If you are serious about the planetry imaging thing, you should get a decent equatorial mount (the C8 can come bundled with an AVX) or get the CPC800 package. The latter is really rather heavy, but so much more pleasant to use for planetary imaging, and it is nice for visual too, and easy to set up with the built-in GPS.

You need a decent plantary video camera, not a DSLR. I now use an ASI224MC , made by ZWO. They cost around £250.  And preferably a laptop with USB3 port  as this will allow you to increase the frame rate

I don't use a Barlow lens. In theory I should, but the seeing here is generally too bad.

You also need to understand how to take and process the video stream from the camera. There are various online guides. 

For the major planets you don't need a flip mirror, but you will need a good finderscope as the planetary video FOV is pretty small. I used a 9x50 RACI fnder.

And you need a ADC to correct for atmospheic dispersion of light from low declination planets. I use the ZWO ADC which costs about £120 (and worth it.)

I hope this helps. Sorry if it's a bit frank but I a ill and typing this asa break from staring at the TV.

"+ the apparent drawbacks of a Mak makes me a bit hesitant about this type of telescope. "

What apparent drawbacks?

The APO scopes you cite are fine instruments, but I don't think they are necessarily what you want for a first astronomical scope.  Reflector scopes are even better at eliminating false colour.  It is quite likely that you will want to replace your 'first scope' with something else as your astronomical interests develop.

You express an interest in GoTo. If you will be observing in a light polluted area, this would be a decided advantage in finding non-obvious objects to observe. If you are not initially interested in long exposure astrophotography, or in visual only, then get an alt-azimuth GoTo.  An alt-azimuth Goto can be used for short exposure astrophotography and for planetary imaging.

I would suggest that should you buy a 150mm APO and a suitable GoTo mount, you will have spent an impressive amount of money and acquired a heavy outfit that may not necessarily suit your ongoing requirements.

I recommend that you give up the idea of buying a "lifetime scope" as your first purchase, and instead buy a smallish telescope (e.g. 127 or 130mm) and alt-az GoTo package. This might cost around £500 (600 euros?) and would provide an adequate introduction to astronomy.  If subsequently you decide you don't like the scope or the mount, or the tripod, or for that matter GoTo, then you can do something about it without much financial pain.   More to the point, having acquired some experience of handling an astronomical telescope and mount, you will be in a far better position to buy an outfit that suits your needs and interests.

You might even have decided that you want More Aperture, which in practical terms means a Newtonian reflector or a SCT.

On 11/03/2020 at 13:02, daslolo said:

yes, it's about deforking, what i want is dovetailing that fork mount, to put other otas on it

Not sure exactly what you want to achieve. You could piggyback a scope of substantial size on top of the fork-mounted C11. Considering the size and weight of the assembly it will just shrug off the weight of a smaller scope.

Is the C11 permanently mounted in an observatory?

I suggest that the probelem is the mount, and if you had a more stable mount, you would not be looking for an electric focuser.  Fixing the mount is easier said than done, but you could for instance look at gettng an EQ-5 style tripod and making an adaptor plate.

I suspect that some of us are getting frustrated by the OP's apparent inability to deliver a detailed report of the problem, while the OP is hiding from a barrage of techy messages.

I did not have anything to do this afrernoon other than try to compile the following, namely some simplified instructions for the OP which also suggest what could be going wrong, if in fact there is a tectnical fault.

I downloaded the Startracker instructions and have copied some relevant passages along wih my own notes.  These notes cover the initial setup of the Polar Home Position and a one-star align.

Setting the Polar Home Position1.  (page 8 Level the mount, if necessary, by adjusting the length of the three tripod legs.2.  (etc)
A bit wordy.
 In plain English, Polar Align the mount, then with counterweight and telescope fitted, position the counterweight at its lowest position (over North leg) and the telescope above the mount and pointed at the pole star.  Do all this with the power OFF.  The setup should look like Fig 3a in the Manual.  If you do not start from this position, the following setups will not work.

Skip a lot of stuff to Page 13 "Initializing the Handbox" (sic).
This section makes reasonable sense (to me, at least). Engage the RA and DEC locks before you start, otherwise you will lose your setup as soon as a clutch slips.
It doesn't say exactly how you enter the numbers, (and I have not been able to see what the display actually looks like) but probably you can select number groups with the arrow keys and then enter numbers with the numbered keys (or whatever)
You can skip through the Daylight Saving by pressing Enter (or so I assume) No daylight saving this week.
Location: Cornelius Varley helpfully provided the Lat/Long for Dartford, and I am copying these details here. "Your location co-ordinates should be similar to E000 13 11 , N51 26 38 (the centre of Dartford). "
If this looks too confusing, use the other option and select your town and city. "London" will be good enough for now. Time zone for Dartford (or London) is 00.
This should conclude the data entry and the next step is a sky align.

Make sure the telescope & mount are at the Polar Home Position and the clutches are locked.
Press 1 x the ENTER button to access the main menu and select the menu item „Alignment“. Then press the ENTER button. Different alignment methods to choose from now appear.  Select „One Star“, and then press the Enter button.
Do what it says, I guess. Use One Star to start with as this is the simplest option.  I am assuming that you will recognise the alignment stars and where they are in the sky.  Pick a likely one and press Enter. The telescope should slew to the (first) star.
What's happened now? The mount should have slewed to the star with at least finderscope-field accuracy, but if you did a good job earlier it may be in the main eyepiece field.
Did it work? The next stage is to centre the star using the direction buttons and accept the setting.  

Something wrong? There are various possibilities.  With 'Another Clone Mount,' doing the final centering kicks up a fair racket, despite the slow speed.  So you should be able to hear if the motors are still working.
Your power supply may not be man enough for the job of slewing the loaded mount without developing a glitch.  Are you using the supplied dry cell pack? Maybe those batteries are past it several months after purchase.  Or did you buy them from Poundland? They'll be rubbish.  I made that mistake once. Get a new premium quality set.  

Or did you use one of the popular power packs that work fine with Celestron and Sky-watcher mounts and lots of others? Did you know that the Exos-2 mounts use a different standard of power plug from everyone else? Here: (from the manual) Connection power supply: DC- plug 5.5/2.5mm.
If you try using a power source with the popular 5.5/2.1mm plug the results are going to be unpredictable.

Another possibility is that some cable is getting snagged in the dark as the mount moves, with unpredictable results.

Paul - I hope that some of this helps.

11 minutes ago, paul schofield said:

Oh really, good spot sir. A bit vague indeed. I have read and read it so many times. 

That's not really the point. Did you polar align the mount and aim the telescope at Polaris (with power off) as the starting point, or did you do something else?

Firther down it says "5: If steps 1 through 4 above were performed with reasonable accuracy, your telescope is now sufficiently well-aligned to Polaris, the North Star, for you to begin making observations. "   which makes their intent clear enough. Particularly with reference to the clearer EQ-5 Synscan instructions which cover the same ground.

1 hour ago, michael8554 said:

Bizarrely you have to read the pdf manual for the Goto kit, not the manual for the mount !

I managed to find it. (I should get a prize).  Reading through this, the directions for the initial Polar Home Position align are a bit vague, but it seems to be the same as for the EQ-5 Synscan cited above. The one star, two star align etc seem to work as for the Synscan.

I tried finding a manual for the Exos-2 Startracker but could not find one. Failing that, I have been reading through the Synscan GoTO manual (since I should be getting an upgrade kit delivered later today.

Nobody has picked up on my point above about pre-align.  With the Synscan, you have to polar align the mount, aim the attached telescope at Polaris, and then turn the power on.  The system now knows roughly where it is: mount setup and level, scope pointed at Polaris.  (And if it isn't, don't expect any of the following to work) If you go for a one-star align on Rigel, select Rigel and the mount will slew till Rigel is in the finder field (we hope). Centre the star in the finder then in the main eyepiece. Job done.

I assume the Exos-2 works either in exactly the same way or close enough so you can figure it out from the manual.

If there is a function to return to the start position, execute it and see what happens.

Badly behaved electronics can often be fixed by that old engineer's trick - turn the power off, count to two and turn it on again, or  a factory reset.

I have looked at my ZWO ADC (which does have the bubble level).

No rattling, no parts at odd angles.  Just a black body with two levers (and the bubble level) sticking out. To adjust it, I move the two long screws in their slots, in opposition.  No need to tighten or slacken anything.

As I understand it, both the optical elements are thin wedges, and rotating them relative to each other creates some colour dispersion to counteract that from the atmosphere.  I hope that helps.