Cosmic Geoff

I have several genuine Ross London telescopes and so have taken an interest in the serial numbers. I have never found a definitive guide to the serial numbers, but the lower the number, the earlier the date of manufacture.  49994 could be of the order of 100 years old. But what is it?  It looks like it could be an exchangeable eyepiece for a spotting scope.

Just now, CraigT82 said:

Well you can trust CN to bash a £125 product because a £3500 version performs better. 

I have the ZWO version and I like it. I use it mainly for imaging but have used it for visual and it does help when targets are low, especially in larger apertures.Takes a bit of practice to set up but well worth it for the price.

I second that.  It's an accessory well worth having.

I have an 84.48 WH LiFePo4 power tank, which I bought because they are lighter and supposedly more durable than lead-acid.  I am happy with it so far, and (wrapped in a clear plastic bag) it was great for working under my car. Also looks like a great emergency light for power cuts.

I also have a car starter, acquired with a telescope, which powers the scope and also can inflate my car tyres.🙂

I also have a 7AH sealed lead-acid battery which I bought several years ago which now seems to have lost capacity. 

I had a similar problem when one of the plastic mouldings forming the extender clamp of a SE6/8 mount leg cracked across.  I stuck it back with Araldite and cut a piece of metal tube to sleeve over the repair, securing it with the Araldite.  Even without paint, the repair is not noticeable unless one crouches down to look.  Note that you do NOT have to do up the clamps too tightly to stop the leg retracting under load.

If you replace the 200PDS with an 8" SCT you will find it is much lighter and easier to handle, and it is much easier to attach sundry devices such as cameras, flip mirrors and filters because of the large focal range.

22 hours ago, FMA said:

Hi, I have a few question.As you can see im bit lost.....If someone would answer me.....

 

1. I f I have a telescope with go to, but im using ipad with skysafari to move it.....is it redundant the goto thing?

2. do you need to polar align a scope and after align to 3 stars every time? can you align just to 3 stars and no polar align? what happens to those which the tree of the neighbour don't allow you to see polaris?

3. its the starsense the only product to align the telescope by itself?

4.if using for visual and go to, why ez its better than equatorial if its the goto moving it for you?

5.to connect ipad to telescope you need a wifi expansion......do the asiair pro include that?

6.if you use skysafari or goto, do you need another small guide scope? I mean. I see people use the big scope and always has a small one with a wide view....but if the goto its taking you to the things, whats the point of the small one?

7.i like the William optics 73 apo. If I buy that one, can I see straight away or need to buy eyepieces?

plenty of doubts as you see......thanks!

 

1: Skysafari etc will not make the GoTo redundant. You still have to use the GoTo setup though you may be able to dispense with the GoTo handset.

2: You do not need to polar align a GoTo mount unless it is the equatorial variety.  You do not need three stars to align - you can align on 1 or 2 stars or 1 planet though this is less accurate.

3: No.

4:  I don't know what you mean.  For visual use, equatorial GoTo is an unnecessary encumbrance compared with alt-azimuth.

5: No idea.

6: A GoTo mount always needs a finder for initial setup. Often a cheap red dot finder will suffice, as you will not be using it during the viewing session.  Guide scope? Are you talking astrophotography? That is a totally different ballgame.

7: No idea. Most vendors supply one eyepiece with an OTA (bare telescope), then you have to buy a set of eyepieces yourself.

If you fitted the motor focuser because of vibration, you can probably ditch it if you are using the EQ3-2.  I found that the AZ-4 and EQ-5 mounts were like solid scaffolding when compared with the lightweight GoTo mount & tripod that came with my 127mm Mak.  They were orders of magnitude less wobbly.

15 hours ago, banjaxed said:

I should have mentioned that I have a motor focuser which does not fit in the present position. I think tube rings are needed to sort things out. Does anyone know if the dovetail fixing nuts are loose or attached to the tube ?

Why are you using a motor focuser at all? I do not have one for my 127mm Mak. In my experience, the more solid the mount, the less one thinks about remote focusing devices.

If I look through the meniscus of my Celestron 127mm Mak, at the positions of the dovetail screws I can just see two screw ends, as though they are screwed through a threaded hole in the tube wall. Further enquiry might be wise.

14 hours ago, banjaxed said:

Just had a thought that it would be easier to move the dovetail to the right position but I am unsure if you can remove the back off a 127 Mak without causing any problems. Has anyone removed the back or is it not recommended ?

I wouldn't take it off if it was mine. And I don't think this is necessary (see above).  Note also that you can swivel the diagonal to any angle you like without having to rotate the main tube in rings.  I have put my 127mm Mak (intended for alt-azimuth mount) on an EQ-5 a few times without feeling I was having a particular problem.

Depends on what degree of rigidity you find acceptable.

The SE 6/8 GoTo mount commonly bundled with the C8 is probably more stable than the AZ5, but still not great. It is stable enough to operate as a portable visual mount but that's it.  The SE 6/8 mount has 1.5" stainless steel legs.   Being a narrow field f10 instrument, the C8 is better suited to rigid mounts with powered tracking etc.

I've seen Mercury with the naked eye in earlier apparitions. It is easier to spot if you know exactly where to look.

As for Pluto, mentioned above, this minor planet will be nearly impossible to see visually.  It is very faint, requiring a large telescope, and at that magnitude there are hundreds of brighter stars in the field. After several attempts, I managed to log Pluto using a 4" refractor, camera, platesolving and star charts.  

I suggest trying out the idea without the friends and family, so you have an appreciation of any difficulties involved.  How, for instance, are you going to find the objects and keep them in the field of view?  How wide is the effective field of view?

If you were buying a car you would shortlist according to the following kind of checklist:

Budget, size of your garage or parking space, no. of seats or luggage space, intended use (commute or track racing), technical spec, fuelling (electric charge point available?).

Same sort of thing with a telescope: budget, max size/weight, GoTo or not, power availability, usability, astrophotography aspirations? 

I did manage to tweak the alignment of a pair of Bresser binoculars which I bought at Lidl. They had two alignment screws on each side hidden under the rubber. They were clearly too cheap to send to a repairer. I had the objective of a vintage telescope replaced and it cost me over £100.

If you cannot source the actual part, you should be able to make up something from standard parts, or have an engineering workshop make one from steel bar stock.

Seeing that long extension tube immediately rings an alarm bell. You need to eliminate it and get the eyepiece closer to the main telescope body. 

I agree with  the comments above.

Don't think that one telescope will do everything, because it won't.

Don't expect it to be cheap, because it probably won't be.

Don't expect amazing views of the planets from a small telescope. To see anything that resembles Michael Wilkinson's image of Jupiter above you need to image it with a large telescope and process the data.

In the UK, buying stuff is cheap, but paying anybody to do work or  make special parts is expensive.

In Algeria as you suggest, importing stuff is expensive but having somebody make parts should be cheap??

The number to select and control the telescope will be set up by you. The first being 1 and any addition being 2.

Depending on the exact hardware involved, you may also have to select a computer port and be sure to use the same port each time you set up the cables.

This laptop has a handwritten sticker on it which reads: "Stellarium 'goto' Ctrl+1".  Another sticker has an arrow and "Port 3 -Scopes."

Few users think that powering the mount with 8x AA cells is a serious option. You could use any sort of suitable external power from any supplier, but the Skywatcher power tank will do fine.

Basically, there are two routes open to you: either take the telescope to somebody who has the experience and expertise to see what is wrong and put it right, which they would probably be able to do quickly.

Or do the work of obtaining said expertise yourself: learn how telescopes of this type are adjusted and tested (collimated), and what you can expect to see as the telescope goes in and out of focus, and how critical the focal adjustment is.

Possible reasons for inability to focus: telescope severely needs collimating, it has been modified for camera use, you have inadvertently included (or excluded) some tubular extender which changes the eyepiece position.  Typical of this design of telescope is that the mechanical range (in/out) of the focuser is fairly limited compared with some other designs where one can hang any accessory on the telescope and still get it in focus.

What is your budget (in Euros etc) for fixing this problem? The more practical solution may be to purchase another mount. Alternatively,  fabricating an altazimuth (movement up/ down and around) mount for a small telescope from basic materials is not beyond the capabilities of the average person.  When I was a youth, I made a mount and tripod for a small telescope from bits of wood and metal.  Or have somebody make the missing parts.

It is not clear what parts are missing. You have highlighted "u-shaped base" which seems to indicate that you in effect do not have a mount. What is the full story? If you cannot complain to the seller, maybe you need to buy another mount.

I have used a binoviewer successfully with my 127mm Mak and my 203mm SCT.

The key issue here is that the binoviewer adds around 100mm to the optical path. This is a major change in path length, and the focus mechanism of the Mak will cope with it if you wind it enough. Point the telescope at a very bright point target, eg Sirius or Venus, and wind the focus in the direction that makes the 'donut' smaller, till it comes in focus.  You will have to do the reverse to stop using the binoviewer.

Some telescope designs, eg the Newtonian reflector, will not cope with the extra 100mm path at all unless you can use a Barlow, but Maks and SCTs will all be fine.

What is the laptop endurance? Several hours is typical.   If that is not sufficient, you'll have to invest in a large heavy battery, plus converters to convert 12v to 240v or 19.5v. Or a long mains cable.

My imaging laptop has a 2 hour endurance, but I manage for the kind of imaging I do.

Depends what you mean by "camera tripod" - some will wave in the breeze, other more expensive ones will be as stable as a budget portable astro mount.  If you have an expensive and substantial camera tripod, by all means try it, otherwise buy an astro mount that is suited for the job. Be aware that camera tripods are designed to hold the camera in a fixed position, not track a telescope across the sky as the earth rotates. 

The dovetail bar is normally at the side of the Mak. If you make use of a camera thread in the dovetail bar, be prepared for finderscope etc to assume an odd position.

1- not significantly. Nothing you need to worry about.  Most lower priced telescope holders are like this.

2- Not entirely sure what you mean, but clamp it in the position that best balances the tube when placed horizontally.

3- Leave them alone till a) you think it needs collimating and b) you have read up on how to do collimation. If the telescope seems to be working well (stars look sharp) leave well alone.