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hey people,

just got my new telescope delivered. its an 8 inch reflector with a weird looking EQ mount. iam having trouble setting up my telescope. also its hard to point at something, along with that, i see the image rotated at 200+ degrees, near to inversion.

any help? how do i proceed?

PS: any help with the setting circles would also be appreciated 

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20171013_192419_HDR.jpg

Edited by ronny_shri
pics

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Sorry I can't help but congratulations on the scope. It looks like you're going to be amazed.

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First off, you're missing the counterweights, so you'll only be able to use it as an alt-az mount for now.  Tip the latitude adjuster all the way back until shorter chromed rod is straight up and down.  That will become your azimuth axis.  The longer chromed rod will then be your altitude axis.  You'll be able to move it up/down, left/right just like a Dobsonian (or cannon) mount.  That should be a lot easier and more intuitive to move about the sky for now.

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39 minutes ago, Louis D said:

First off, you're missing the counterweights, so you'll only be able to use it as an alt-az mount for now.  Tip the latitude adjuster all the way back until shorter chromed rod is straight up and down.  That will become your azimuth axis.  The longer chromed rod will then be your altitude axis.  You'll be able to move it up/down, left/right just like a Dobsonian (or cannon) mount.  That should be a lot easier and more intuitive to move about the sky for now.

sir, first off thanx alot to reply so quickly. i was searching for the same thing u mentioned so thank. if iam correct , you are telling me the way to make my EQ mount into an ALT-AZ mount. though i did not get it completely . again, i knw from your end you tried to make it as simple as possible, but if u may, pls elaborate the steps. 

i will keep posting the pictures for your advice as well.

hope u understand and neglect the stupid questions iam asking and help a newbie get started :D  

thnx again

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1 hour ago, domstar said:

Sorry I can't help but congratulations on the scope. It looks like you're going to be amazed.

thnx alot , i hope to see some good views.

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I think I can see a counterweight in the 1st picture posted, on the table to the left of the scope ?

Is the mount equipped with slow motion controls ? - I can't see any of those.

You should be able to rotate the scope tube, to change the orientation of the view, if you loosen the tube rings a little - be careful to support the back end of the scope while doing this.

 

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41 minutes ago, John said:

I think I can see a counterweight in the 1st picture posted, on the table to the left of the scope ?

Is the mount equipped with slow motion controls ? - I can't see any of those.

You should be able to rotate the scope tube, to change the orientation of the view, if you loosen the tube rings a little - be careful to support the back end of the scope while doing this.

 

no sir, that is one i took out from a barbell that i had in my gym. i tried using it as a counterweight. and no, the mount is not equipped with slow tracking knobs. 

iam able to rotate the OTA ,  but i do not knw how to make it point where i want it to point. should i post more pics of my assembly for your reference?

 

btw thnx for your post  

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Here is a photo of an equatorial mount being used as an alt-azimuth mount but with the counterweight bar missing on this one. In the second photo I have shown what you will need to move to get your mount into the same configuration. The bolt that sets the latitude of the mount will need to be loosened and then tightened with the mount in the new position. The counterweight bar can stay on the mount.

post-3933-14073952817648_thumb.jpg

20171013_192403_HDR.jpg.8183dbd36de97fcb1d03689383c1de82.jpg

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Thanks John, those pictures help a bunch to explain what I was going for.  The OP may need to move the scope forward or backward in the tube rings to achieve balance in altitude as well.

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hey , i tried to modify it as suggested. here are the results, hope i did it right.

iam able to rotate it in x and y axis. i hope that was the goal.

.

.

i would love your inputs and suggestions .

PS: what more do you think i should do? iam hyper excited :D

 

thnx again for replying .  @Louis D @John @domstar

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Looking good! Probably better with the weight on it to keep things balanced.

What is the long metal bar across the top of the scope?

Do you have a finderscope? If not you will have trouble finding things but otherwise try sticking an eyepiece in and looking at a bright star to see if you can focus.

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1 minute ago, Stu said:

Looking good! Probably better with the weight on it to keep things balanced.

What is the long metal bar across the top of the scope?

Do you have a finderscope? If not you will have trouble finding things but otherwise try sticking an eyepiece in and looking at a bright star to see if you can focus.

thnx alot for your reply. the weight is not actually doing anything as it is not gonna move in that direction. but yea, i will let it be there.

the metal bar u see is to move the scope around by holding on to it.

yes i did get a finderscope with it (a small one though), you can see it in the previous pics. also i was thinking about replacing it witha green laser. what would you suggest i do?

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Judging from the previous photos you can slide the bar that is currently serving as your vertical axis over to get the telescope as close as possible to the centre of the mount. Once that is done turn the telescope to the horizontal position and slide it back and forth in the rings until it is well balanced. You can also twist the scope in the rings to angle the focuser up slightly. At low elevations that will be a bit more comfortable and it will also allow you to look through the finder more easily. You will want to roughly line up the finder and telescope on a distant object before nightfall. Find the furthest thing that you can see with the telescope and then adjust the finder to match. You will then have to do this again at night on a bright star or planet. I would not use a green laser. A red dot finder will do pretty much the same job without affecting pilots or drawing unwanted attention to you. 

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7 minutes ago, ronny_shri said:

thnx alot for your reply. the weight is not actually doing anything as it is not gonna move in that direction. but yea, i will let it be there.

the metal bar u see is to move the scope around by holding on to it.

yes i did get a finderscope with it (a small one though), you can see it in the previous pics. also i was thinking about replacing it witha green laser. what would you suggest i do?

I actually think the weight is quite useful to have there. Even though there is no movement in that direction, the whole rig is quite heavily weighted on the scope side in the alt-Az configuration so you need to be wary it doesn't topple over. The weight will help avoid that.

I would pop the Finder scope on and see if you can get it aligned with the eyepiece view. Easiest to do in daylight on a distant pylon or aerial. Laser pointers can be quite controversial because of the risk of accidentally targeting aircraft. I tend to think that they are best kept for outreach sessions where you flick them on and off relatively quickly and are focussed on what is in the sky all around you.

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I think you did very well in your choice of instrument - an 8" (inch) Newtonian-Reflector truly is a "Lifetime-Telescope." by this I mean that with aperture like that, it can deliver good views of new and interesting DSO's, and other such objects, every night of one's life - if you started your observations the day you were born! Now one thing you'll be wanting to change:

The finder-scope I see on it will give you much unnecessary pain & suffering. Two reasons why - 1.- It's really to small, in terms of aperture, to be able to locate many things out there. I am guessing it's about a 6 X 30mm. And I'd suggest an 8 or 9 X 50mm model. And 2. - It's straight-through optics means you have to bend and twist your neck to see through the thing in the first place. My personal favorites are the RACI finder-scopes. RACI means 'Right-Angle Correct-Image' - such as the one shown here:

 

59e16d060f5ea_GSO8X50mmRACIFinder-ScopewithBracket.thumb.jpg.ce9cdb70f9349333b6f8f4caaf833a3c.jpg

 

Everyone has a favorite design. Some people prefer the use of electronic-finders that work by projecting a red-dot on the view of the sky through the finder. And some people like having both types. There's no right or wrong, it's what you like best.

Keep us updated, please? It's to be expected to have many questions to get the most from your beautiful telescope. And we enjoy helping to provide answers. And you'll soon (sooner than most people think) be one of the people answering questions from other people who just bought a wonderful, new telescope!

Enjoy!

Dave

Edited by Dave In Vermont
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Hopefully someday you can get the proper counterweight for it, so you can use it as it was intended, as an equatorial mount.  If and when that day comes, check back in with us, so the EQ crew can chime in with their helpful suggestions.

Spend your time getting familiar with aiming and focusing your telescope on bright objects.  Also, you should do a quick star test of mirror collimation by centering Polaris and then defocusing it to check that the diffraction rings are round and centered within each other.

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Astroboot often have counterweights listed, although you need to check the diameter of the shaft it is going on as they do vary. Also check pricing vs FLO as Astrobbot shipping can be expensive for large/heavy items.

http://www.astroboot.co.uk/AstroBoot

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10 hours ago, Louis D said:

Hopefully someday you can get the proper counterweight for it, so you can use it as it was intended, as an equatorial mount.  If and when that day comes, check back in with us, so the EQ crew can chime in with their helpful suggestions.

Spend your time getting familiar with aiming and focusing your telescope on bright objects.  Also, you should do a quick star test of mirror collimation by centering Polaris and then defocusing it to check that the diffraction rings are round and centered within each other.

all i understood was the counterweight part, which the provider will dispatch within few days. will ping you asa i get'em. meanwhile iam using my gym weight plates and it is set up as an alt-az mount config. 

its monsoon season here in india, so i think i need my luck to get a clear sky night, but still lets hope for the best

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11 hours ago, Dave In Vermont said:

I think you did very well in your choice of instrument - an 8" (inch) Newtonian-Reflector is truly is a "Lifetime-Telescope." by this I mean that with aperture like that, it can deliver good views of new and interesting DSO's, and other such objects, every night of one's life - if you started your observations the day you were born! Now one thing you'll be wanting to change:

The finder-scope I see on it will give you much unnecessary pain & suffering. Two reasons why - 1.- It's really to small, in terms of aperture, to be able to locate many things out there. I am guessing it's about a 6 X 30mm. And I'd suggest an 8 or 9 X 50mm model. And 2. - It's straight-through optics means you have to bend and twist your neck to see through the thing in the first place. My personal favorites are the RACI finder-scopes. RACI means 'Right-Angle Correct-Image' - such as the one shown here:

 

59e16d060f5ea_GSO8X50mmRACIFinder-ScopewithBracket.thumb.jpg.ce9cdb70f9349333b6f8f4caaf833a3c.jpg

 

Everyone has a favorite design. Some people prefer the use of electronic-finders that work by projecting a red-dot on the view of the sky through the finder. And some people like having both types. There's no right or wrong, it's what you like best.

Keep us updated, please? It's to be expected to have many questions to get the most from your beautiful telescope. And we enjoy helping to provide answers. And you'll soon (sooner than most people think) be one of the people answering questions from other people who just bought a wonderful, new telescope!

Enjoy!

Dave

thanx alot @Dave In Vermont , i will keep updating the pics as i proceed . 

thnx for your reply :D

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6 minutes ago, ronny_shri said:

its monsoon season here in india, so i think i need my luck to get a clear sky night, but still lets hope for the best

Worst case, set it up inside pointing out a window at the most distant object you can see which is hopefully over 1000 feet away.  See if you can put that object in the view finder first and then see if it is in the main telescope's view when using your lowest power eyepiece (biggest mm marking).  Then try to bring it to focus.  It may still be too close and you may have to lift the eyepiece up and out of the focuser to reach focus, just be careful.  If the two aren't pointing at the same object, adjust the front and back screws on the finder until they are.

You may want to investigate getting a reflex finder.  They come in many types.  Red dot, Telrad, QuikFinder, etc.  Anything would help getting the scope in the right vicinity.

I use a green laser sight as well, but you have to know your local laws and be aware of local aircraft flight patterns.  I have no idea what the laser pointer laws are like in India.  They are downright draconian in Australia.  In the US, no one really cares what you do with one until you shine it in a pilot's eyes, then they will send police helicopters out to hunt you down with IR cameras.  I'm not exaggerating.

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5 hours ago, Louis D said:

Worst case, set it up inside pointing out a window at the most distant object you can see which is hopefully over 1000 feet away.  See if you can put that object in the view finder first and then see if it is in the main telescope's view when using your lowest power eyepiece (biggest mm marking).  Then try to bring it to focus.  It may still be too close and you may have to lift the eyepiece up and out of the focuser to reach focus, just be careful.  If the two aren't pointing at the same object, adjust the front and back screws on the finder until they are.

You may want to investigate getting a reflex finder.  They come in many types.  Red dot, Telrad, QuikFinder, etc.  Anything would help getting the scope in the right vicinity.

I use a green laser sight as well, but you have to know your local laws and be aware of local aircraft flight patterns.  I have no idea what the laser pointer laws are like in India.  They are downright draconian in Australia.  In the US, no one really cares what you do with one until you shine it in a pilot's eyes, then they will send police helicopters out to hunt you down with IR cameras.  I'm not exaggerating.

thanx @Louis D , i will do as u said, and try to align the finder with my telescope. 

well green laser is just "way cooler" than our usual refractor finders. plus it makes me feel like i have a light saber attached to my telescope so makes it much more fun tis way.  what i thought was , putting a laser on to the OTA will remove my efforts of bending and looking through the small scope, rather i can comfortably see a green line running in the night sky towards the object i want to point it at, so just a bit of dedicated and precise alignment and i guess iam set. iam also trying to get a decent finder as @Dave In Vermont suggested, but i broke my wallet with this set up so i think i have to wait for a while before i get enough $$$$ to buy anything else.

 

and about the LAW regarding laser here in india, well as sad it may sound , but police here actually do not care at all about these issues. basically because there is nothing for them to gain ( or earn ). plus air traffic in my area is not that much . so if you experts feel that a green laser will do the job, all i have to do is pop in a pair of AAA+ in them and iam set.

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Relative to GLPs, here's a Cloudy Nights thread on the subject.  I went this route, with a picatinny rail mounted green laser sight.  It has built in alignment screws that work well enough.  Once set, I just leave one on each scope since they're cheap and solid metal mounted on solid metal and thus never lose alignment.  The remote momentary switch is really nice.  I can push it without jarring the scope if I want to verify where I'm pointed.  Once aligned, you can see the tip of the light beam in the center of the field of view in the main scope.

I started using them because my aging back and neck have a hard time bending around to use a reflex sight.  That's doubly true when locating objects near zenith.

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It should be pointed out that using green-lasers, either as a type of finder or to point out objects in the sky, can be very hazardous to aircraft as well as to your own personal freedom!

I don't know the laws, or restrictions, on green-lasers in India, but in the USA if you hit a passing aircraft - you can be put in federal-prison for up to 20 years! Low-power "Greenies" can have a range of upwards to 2½ miles. It's all to easy to accidently 'flash' this into the cockpit of the aircraft and interfere with the pilot or co-pilot's vision. If you blind the flight-crew operating the aircraft - you could cause a tragic accident that results in the aircraft crashing to the ground and killing those onboard. This is why the laws are meant to prevent use by anyone other than by people who will keep the direction of these devices under constant watch. And why the green-lasers are only available with a "momentary-switch." But what is possible is to easily by-pass this switch and allow it turned on and left without constant supervision.

59e2bfbfa26de_ON-OFFSWITCHFORLASERS1.JPG.ddc6817921e7f05a0205c4af3f281f10.JPG

 

And some people actually use these to fire them at aircraft purposely - usually drunken idiots. If you wish to use these as a finder, you really need to check your local laws first. Imagine how you'd feel if you accidently caused a 747 loaded with passengers to crash! It is up to you, but I'd strongly suggest finding another way to help you find things up in space.

'nuff said -

Dave

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Also, it only takes one incident for amateur astronomers to be equated in the popular mind with drunken idiots who point green lasers at aircraft. And we don't want that. These devices are intended for pointing at things in lecture theatres. So keep them there.

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      Also, how do you support the mirror? Would a support that replicates the telescope mirror cage be appropriate - a 27-point in our case? Or is it a matter to build a concave support that holds the back of the mirror? How accurate/solid should that support be?
      Any experience out there??
       
      I reckon that's enough as a start - thanks everybody in advance for your contribution.
       
      Stay safe! Michele
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