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View Full Version here: : Setting up Luminova telescope


Astrochem
02-07-2015, 10:24 AM
Hello, I'm brand new to the site and have questions about setting up a Luminova telescope, model 40-114675. The manual talks about the polar axis, declination axis and hour axis and many clamps and screws, but the drawings are so small it's hard to see which is which. I'm attaching pics and I'm hoping someone can be patient enough to help me understand what I need to do. Thanks in advance for helping.

The 1st pic is the accessory tray fitted to the tripod legs. There were rubber mounts on the end of the flanges, but I don't think they should stay attached because at least one of them will overlap the hole for an accessory. Is this correct?

The 2nd pic is the first of the equatorial mount. I would like to know which scale is showing, and the purpose of the bolt on the left. It doesn't seem to perform any function that I can see. Tightening or loosening it has no effect on the movement of the mount.

The 3rd pic of the second of the mount. What is the purpose of the bolt on the right? Again, I see no difference in movement of the mount when it is tightened or loosened.

The 4th pic shows the entire mount with all three scales. Which ones are they, from top to bottom?

Finally, the last pic shows the lens setup. This telescope came with three small lenses in individual containers, an eyepiece tube about six inches long and a Barlow lens. I think the setup should be either the eyepiece tube and a small lens, or the Barlow lens and a small lens, but not both the eyepiece tube and Barlow with a small lens. At the moment, no matter what combination is used, the view through the lens is cloudy.

I understand the function of the finderscope for this telescope, and I understand that is necessary to align the view in the finderscope with what is seen in the telescope. The view through the finderscope is as clear as I would expect.

Thanks again for reading through this and helping me to understand.

Astrochem
03-07-2015, 02:09 AM
Hi, I was able to figure many things out after reviewing it all again but still need some help.

I now understand the function of all clamps and dials. I'm adding this information so anyone who has questions can benefit from the explanation. The sequence of the scales from top to bottom is declination - hour - polar. I can see where the bolt I identified in the 2nd pic is the fine polar axis control and I can see that the bolt I identified in the 3rd pic locks the equatorial mount completely.

I followed the procedure in the manual for balancing the telescope. After setting the polar axis to my latitude (37deg), setting the declination to 90 and rotating the scope until the counter weight rod was horizontal, the telescope was not balanced. The counter weight is at its lowest position and cannot add any more gravity to that side and moving it up the rod will make the situation worse.

I've taken a pic of the setup and I have the hour axis locked.

What to do?:shrug:

ZeroID
03-07-2015, 05:59 AM
Hi Brian and :welcome:.
This 'Equatorial' stuff is a bit confusing to begin with isn't it ?

Please forgive me if I take you back to basics in explaining a few things.
The purpose of the Equatorial mount you have is to allow it to track a stars (or planet, moon etc) movement during the night so it can be viewed without constant readjustment and also for imaging using longer exposures.
The picture in the last post shows the Polar axis. You say you have set that to 37*, your latitude. This then needs to be aligned along a Nth to Sth line with the scope end towards the Sth ( Most instructions refer to the Northern hemisphere which is reversed of course ). That should point it at the Sth Celestial Pole (SCP) the centre of our astro view.
The scope can then be pointed at any object in the sky and should 'follow' it if motorised or at least stay in view if you slowly rotate the flexi knob for the Polar axis.

A couple of proviso's.
The DEC ( Declination) scale on most mounts is not particularly accurate and also relies on the mount being level at the head. There are free Inclinometer applications for phones\tablets which can get this more accurately.
The Nth\Sth line can be found using a compass (allowing for magnetic deviation for your location) or even a phone\table compass app although they can be extremely inaccurate due to local metal influences etc.

The simplest most accurate way is to use a plumb bob at Solar Noon. (Google this for an explanation and time for your location). This is when the sun is the exact North facing point during the day and a shadow line from a plumb bob will be exactly NtTh to Sth. I painted a thin yellow line on my driveway originally and when I built the Observatory and pier did first alignment the same way.

Re the EyePieces (lens as you call them) start with the EP with the largest number (25 ?). Place it in focusser and rack it in and out to see if it reaches focus. Probably not so add the 6" tube and try again. It should at some point become sharp. It will be a bit critical so take it slowly. If it is still not clear and you have checked that there is nothing covering or obstructing the mirrors you may have a problem.

Try this during the day, point it across the road or somewhere a bit distant. Hopefully it should focus and be OK. During the day you will find the viewed image a bit bright and soft, astro scopes are designed for night use and collect a lot of light which can wash out the view.

Next best advice (if you haven't already got it) is to download Stellarium (free) and start learning where things are and how it all works. It can be set to show the sky at your location and therefore show what is viewable right then. It also will give some excellent tuition about the sky and astronomy with it's coordinate systems.

OK, that will do for now. Come back and tell us how it goes and we'll start you down the dangerous and expensive path of astronomy. :thumbsup: :D

julianh72
03-07-2015, 10:57 AM
It's surprising that a manufacturer would sell a telescope with an equatorial mount that can't be balanced! If the mount and scope are well-matched, you would expect to be able to get a good balance with the counterweight somewhere like half to 2/3 down the shaft. Try contacting the dealer and asking if they can give you an extra weight. If they can't oblige, many telescope shops sell extra counterweights, or you might be able to buy one second-hand.

As a temporary measure, try rigging up some extra counterweight, such as a small bucket with gravel or similar that you can hang from the counterweight shaft. (Just make sure that your temporary weight will clear the south-pointing leg as you swing the scope through the vertical plane.) This will allow you to add / subtract weight until you get a good balance, and then you know what size weight you are looking for.

geoluke
18-08-2015, 09:00 PM
I have the same or a very similar scope that I purchased second hand. I had the same problem with mine so I'd suggest that it is probably a common issue with the Luminova telescope and I presume that the telescope is to large for the mount. But anyway I managed to solve my issue with some some chunky magnets that I had lying around (those old horse shoe kind which were pretty heavy). Obviously if you don't have enough magnets or something similar you'll have to add extra weight another way as julianh72 suggested.

OICURMT
18-08-2015, 10:14 PM
FYI... OP is in n the USA...

Scope should be aligned to Polaris