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Meade always supplys an inexpensive 90° prism-diagonal with the LX90's - has for years. As well as a 26mm Plössl eyepiece. I'd suggest getting a 2" star-diagonal. These will come with a 1.25" adapter so you can use both 2" and 1.25" eyepieces.

Until you've had the scope cooled for about an hour in the outside air, and you've focused outdoors on a distant object/building/etc - I'd not be worried about collimation. It's pretty hard to knock these telescopes out of collimation. Like dropping it down a flight of stairs.

Until you find out what sort of objects 'up there' interest you the most, I'd hold off on any expensive eyepieces - though your scope is quite worthy of top-end ones - and maybe look at some used eyepieces for now. These can be re-sold for about what you pay for them, and they'd help you learn about your preferences.

Have fun -

Dave

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1 hour ago, Jimmystargazer said:

Another question.. I only have a 26mm eye piece. I assume I need another to view planets? Like a 12.4mm.. would love to view Jupiter and Saturn rings etc.. used the other night and literally saw nothing like I know the telescope is capable of..  if I do need other eye pieces what are your thoughts on a zoom eye piece? 8-30?.. or some thing similar?

Again thank you all for you help and in out.

Jimmy

Another question?  No problem at all.  You've come to the right place.

Your 200mm Schmidt has a focal-length of 2000mm, and is considered a "slow" telescope, at its f/10 focal-ratio.  The nice thing about telescopes with slower focal-ratios is that most any inexpensive eyepiece will work very well and provide pleasing views.  For the 1.25" format, a 32mm ocular would afford one of the lowest powers practical...

2000mm ÷ 32mm = a power of 63x; a 40mm: 50x, and the very lowest power available in the 1.25" format...

http://www.365astronomy.com/32mm-GSO-Plossl-Eyepiece.html

http://www.365astronomy.com/40mm-GSO-Plossl-Eyepiece.html

Vixen makes very good Plossls... https://www.firstlightoptics.com/vixen-eyepieces/vixen-npl-eyepieces.html

I have the Vixen 6mm and 30mm...

58e445bccfc67_Vixen6mm30mm.jpg.f95b93109c219fd929d2ab7a0c2b79e8.jpg 

The 30mm's field-lens is extraordinarily-large, and through which to look.

The Antares Plossl line-up... http://www.rothervalleyoptics.co.uk/antares-plossl-eyepieces-125.html

But where a Cassegrain really puts forth lies at the moderate-to-high powers.  On most nights, you can use an 8mm...

2000mm ÷ 8mm = 250x, and for the Moon, the planets, and double-stars...

http://www.365astronomy.com/8mm-the-planetary-uwa-eyepiece-58-degrees-1.25.html

This 9mm(222x) has a somewhat wider field-of-view...

http://www.365astronomy.com/TS-Ultra-Wide-Angle-Eyepiece-9mm-1.25-66o-with-Improved-Coating.html

If you can wait on the boat, and do without the chromed barrel, this is the same eyepiece...

http://www.ebay.co.uk/itm/1-25-31-7mm-Ultra-Wide-Angle-9mm-Eyepiece-Lens-66-Deg-for-Telescope-Best-track-/152129833857?hash=item236ba50b81:g:G8wAAOSwAuNW3lNp

Incidentally, you do not have to purchase eyepieces and accessories of the same brand as the telescope.  I've encountered some who think that you do, that they must match, but that is incorrect.  Any brand of telescope may use any brand of eyepiece or accessory.

For a relatively-moderate power, something in the 16mm+/- range would do nicely.

Avoid eyepiece sets, such as these...

https://www.harrisontelescopes.co.uk/acatalog/795.jpg

https://www.harrisontelescopes.co.uk/acatalog/celestronepkit.jpg

https://www.harrisontelescopes.co.uk/acatalog/series4000set.jpg

https://images-na.ssl-images-amazon.com/images/I/51YYSxbn9IL._SY355_.jpg

It's best, rather, to put together a set over time -- over the weeks, the months, and the years even -- and tailored to your observing habits.

Always give careful thought to what is placed between the eye and the sky at night, and for best results.

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For the record, when observing at night, it makes no difference if the images are backward or upside-down, therefore always use a star-diagonal at night.  Now, you can use an Amici at night, but the view may be narrower, in addition to seeing what is known as an "Amici line" when viewing brighter objects...

post-232934-0-79911600-1426806265.jpg

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Hiya, has anyone mentioned dewing of the corrector plate yet? (glass bit at the front). if you don't already have a dew shield I'd make or buy one, they are an absolute must for an SCT type telescoope like this. Dewing of the corrector plate would make the image pretty soft so worth checking for.

Easy way to check collimation is to defocus a star in the centre of the eyepiece, it should look like a doughnut with the inner circle dead centre of the outer circle. If the inner circle is off to one side then the scope needs collimating in which case follow this video guide (be careful of screwdrivers and corrector plates!) 

 

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When doing the 'Star-Test' for collimation, a magnitude 2.0 star is suggested. Polaris (alpha-Ursa Minor) is the best choice - as it won't be moving across the sky by much at all. Start with about 200X and slowly increase untill you have a good view of the difraction-rings (circular-lines around the 'donut')

Dave

 

P.S. When using a screwdriver near your corrector-plate, keep the scope either level or slightly nose-down - this to protect the corrector when you manage to drop the screwdriver. :p

 

2b8e9b4a-0de4-4d48-a008-e1e1c8937967.gif.jpg.035e0437a9e5e54cf6646a8ac0b75c20.jpg

Diffraction-Rings

Edited by Dave In Vermont
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My first scope was an LX90 too, it's a good quality instrument and you can get a lot out of it, you just have to be patient and work through the various challenges.

Collimation

Collimation is important, and you can do a quick star test to get a rough idea of what it is currently like, as mentioned in the post above. I'd be inclined to only check the collimation to try to gauge if it's out or not without trying to improve it initially though. If the inner part of the donut is roughly centered when a star is out of focus, it's likely close enough to make do with for a couple of nights whilst you get used to everything else first. It will also give you a reference point for when you do start to try to improve collimation which is quick to do once you know how (5-10 mins) but can easily end up taking up a few sessions when you're learning.

Cooling

The comment about letting your scope have chance to equalise the temperature with ambient is vital, don't bother trying to collimate until the scope has had an hour or so to equalise.

Alignment

As far as stars for alignment not been visible, do you mean the scope isn't pointing in the correct direction or close enough to them, or that they're blocked by trees/house etc If the latter, you can request the autostar select another star. I forget if it's via pressing mode or the up/down arrow off hand though. It's in the manual either way.

As long as your tripod is roughly level and you put the scope pointing north and have the date/time/location correct, the scope shouldn't be too far away from the target star, although it's unlikely to be in the eyepeice, it should be in the finder or very close.

One tip for pointing the scope north. Center polaris in the eyepeice and then slew the scope in the vertical direction only until it is horizontal (use a spirit level when you're close). That is assuming you're in Alt/Azimuth mode and not using a wedge, check your autostar is correctly configured for that. If it's set to polar and you're not using a wedge you'll run into all kinds of problems.

Focusing can be tricky to do well at first and on some nights if the seeing is poor you'll never really feel like anything is in focus.

Dew Shield

The earlier post about a dew shield, do not ignore that advice. Get an inexpensive 8" flexi shield which should be around £25 (or search the forums for examples of people building their own), it's invaluable.

SCTs will collect dew like there's no tomorrow and once it sets in, that's it, you're done for the night as you can't just wipe it off and even if you heat it to evaporate, prevention is better than cure as deposits can build up on the corrector plate.

I as I imagine most others do, use a dew shield + heater strip. You can avoid the cost of a heater strip for a while, but I would buy a dew shield before anything else, although I'd also consider picking up a star diagonal as well, your back will thank you on that one :)

A first scope is quite the learning curve as you'll be unsure if issues are you or the scope at first. The comment about heading to a astro meetup is a good one. Other than that, try not to get frustrated, a bit of patience and persistence and it'll eventually become second nature and you'll wonder why you ever struggled :)

Edited by Hicks
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2 hours ago, Hicks said:

A first scope is quite the learning curve as you'll be unsure if issues are you or the scope at first.

Never have a read a truer word and it doesn't matter what sort of telescope you have!

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I would ignore collimation until you can at least see things in some manner, there is a greater chance of making it worse rather then better. The almost standard way is to check with a star test and as you seem not to be able to get a star in sharp focus then a star test is pretty pointless. Collimation on an SCT is not really something to do without a fair degree of research first and a reasonable amount of preparation.

Have you changed the data ? I assume here that there is no GPS on the scope, and even if there is it is a good idea to set your own. GPS can take some time to get a location and other data. Simple one are you telling it DST = On ?

If you want an eyepiece then get a 32mm plossl or a 40mm plossl, at this time get the widest field of view you can, especially with the focal length of the LX90.

Alignment is usually easy but again with the focal length and reduced field of view North has to be North and level has to be Level. A compass is not accurate enough for North. And as Polaris is off true North about the same as a compass is then neither is aiming it at Polaris. The Meade "Level and North" is relatively easy to get going with but it does all rely on the scope and mount being fairly accurately level and North as the initial start position. Spend 5 to 10 minutes getting it so.

One other aspect is if there was/is old data in there then you may be better resetting the handset and entering all aspects again yourself. Sometime they just need it doing - half convinced that old data lingers around and so upsets things.

Aligning finder and main scope is a daytime exercise on a distant object, distant = about 2 miles, not the ariel on the roof over the road.

By the way forget an erecting prism, little point in one with that scope, when you get it going.

Edited by ronin
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On 05/04/2017 at 22:26, Dave In Vermont said:

When doing the 'Star-Test' for collimation, a magnitude 2.0 star is suggested. Polaris (alpha-Ursa Minor) is the best choice - as it won't be moving across the sky by much at all. Start with about 200X and slowly increase untill you have a good view of the difraction-rings (circular-lines around the 'donut')

Dave

 

P.S. When using a screwdriver near your corrector-plate, keep the scope either level or slightly nose-down - this to protect the corrector when you manage to drop the screwdriver. :p

 

2b8e9b4a-0de4-4d48-a008-e1e1c8937967.gif.jpg.035e0437a9e5e54cf6646a8ac0b75c20.jpg

Diffraction-Rings

Thank you Dave.

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On 07/04/2017 at 17:02, Hicks said:

My first scope was an LX90 too, it's a good quality instrument and you can get a lot out of it, you just have to be patient and work through the various challenges.

Collimation

Collimation is important, and you can do a quick star test to get a rough idea of what it is currently like, as mentioned in the post above. I'd be inclined to only check the collimation to try to gauge if it's out or not without trying to improve it initially though. If the inner part of the donut is roughly centered when a star is out of focus, it's likely close enough to make do with for a couple of nights whilst you get used to everything else first. It will also give you a reference point for when you do start to try to improve collimation which is quick to do once you know how (5-10 mins) but can easily end up taking up a few sessions when you're learning.

Cooling

The comment about letting your scope have chance to equalise the temperature with ambient is vital, don't bother trying to collimate until the scope has had an hour or so to equalise.

Alignment

As far as stars for alignment not been visible, do you mean the scope isn't pointing in the correct direction or close enough to them, or that they're blocked by trees/house etc If the latter, you can request the autostar select another star. I forget if it's via pressing mode or the up/down arrow off hand though. It's in the manual either way.

As long as your tripod is roughly level and you put the scope pointing north and have the date/time/location correct, the scope shouldn't be too far away from the target star, although it's unlikely to be in the eyepeice, it should be in the finder or very close.

One tip for pointing the scope north. Center polaris in the eyepeice and then slew the scope in the vertical direction only until it is horizontal (use a spirit level when you're close). That is assuming you're in Alt/Azimuth mode and not using a wedge, check your autostar is correctly configured for that. If it's set to polar and you're not using a wedge you'll run into all kinds of problems.

Focusing can be tricky to do well at first and on some nights if the seeing is poor you'll never really feel like anything is in focus.

Dew Shield

The earlier post about a dew shield, do not ignore that advice. Get an inexpensive 8" flexi shield which should be around £25 (or search the forums for examples of people building their own), it's invaluable.

SCTs will collect dew like there's no tomorrow and once it sets in, that's it, you're done for the night as you can't just wipe it off and even if you heat it to evaporate, prevention is better than cure as deposits can build up on the corrector plate.

I as I imagine most others do, use a dew shield + heater strip. You can avoid the cost of a heater strip for a while, but I would buy a dew shield before anything else, although I'd also consider picking up a star diagonal as well, your back will thank you on that one :)

A first scope is quite the learning curve as you'll be unsure if issues are you or the scope at first. The comment about heading to a astro meetup is a good one. Other than that, try not to get frustrated, a bit of patience and persistence and it'll eventually become second nature and you'll wonder why you ever struggled :)

Thank you Hicks.. star diagonal on order..

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On 05/04/2017 at 02:40, Dave In Vermont said:

Meade always supplys an inexpensive 90° prism-diagonal with the LX90's - has for years. As well as a 26mm Plössl eyepiece. I'd suggest getting a 2" star-diagonal. These will come with a 1.25" adapter so you can use both 2" and 1.25" eyepieces.

Until you've had the scope cooled for about an hour in the outside air, and you've focused outdoors on a distant object/building/etc - I'd not be worried about collimation. It's pretty hard to knock these telescopes out of collimation. Like dropping it down a flight of stairs.

Until you find out what sort of objects 'up there' interest you the most, I'd hold off on any expensive eyepieces - though your scope is quite worthy of top-end ones - and maybe look at some used eyepieces for now. These can be re-sold for about what you pay for them, and they'd help you learn about your preferences.

Have fun -

Dave

Hi Dave.. hmm.. but of a variation in costs out there... Would this do?

https://www.amazon.co.uk/gp/aw/d/B007RTTLUW/ref=mp_s_a_1_14?ie=UTF8&qid=1491863412&sr=8-14&pi=AC_SX236_SY340_FMwebp_QL65&keywords=2"+star+diagonal

Or anything else you'd advise?

Cheers.

 

Jimmy

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I have a SCT of the same aperture and focal length. I use 25mm, 15mm and 8mm eyepieces with it. All are 1.25". You only want 2" eyepieces for lowest power/widest field as the 1.25" are cheaper and more widely available. Plossl types are good enough at 25mm and 15mm unless you have exacting requirements or deep pockets. I have not invested in any lower power (wider field) or 2" eyepieces as I have other scopes for that.  For my scope the cost of a 2" visual back, 2" diagonal and 2" eyepiece adds up to an off-putting sum. But if you have no other scope you may feel it's worth it.

You will need to get the finder (finders) to work and be accurately aligned before you can proceed to aligning and using the GoTo electronics, as the field of view of the main scope is fairly small. Assuming the hardware works as it should, you will scarcely need the finder once the GoTo is set up, and you should be able to find large numbers of objects.  While GoTo systems differ, there is usually a choice of alignment modes e.g. One Star or Solar System object - quickest and least accurate, Two Star - more accurate , Three Star - most accurate and the most fiddly.

Even if the mount has an equatorial wedge (and corresponding settings in the software) you should get used to using it strictly in alt-azimuth mode (mount base horizontal) first - that may prove challenging enough to start with.:icon_biggrin: The equatorial wedge is principally for astrophotography.

I'm not sure how your Meade is powered, but if it uses internal dry cells, think about getting an external power pack for it soon.

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To find the magnification of eyepieces for your telescope, you simply divide the Focal-Length (FL) of the telescope by the FL of the eyepiece. Example:

Let's say your scopes' focal-length is 1,000mm. And you give it an eyepiece of 800mm. - you do this:

1,000mm / 8mm = 125X

I hope this helps! :thumbsup:

Dave

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14 hours ago, Jimmystargazer said:

Next thing to buy is a better eye piece.

Would love to show the kids close up of the moon's craters and  Saturn and its rings if that's possible on my scope.

2" 8mm option?

Thoughts?

Cheers.

Jimmy

Were you able to determine that you can in fact connect a 2" diagonal to the telescope?  You will need a specialised adaptor to connect one, if one is not already fitted...

https://www.telescopehouse.com/accessories/meade-lx/meade-sct-thread-to-2-adapter.html

The goal of upgrading to the 2" format is in realising the lowest powers with the telescope.  For example, you can insert this 2" 56mm ocular for one of the lowest powers with your telescope...

https://www.harrisontelescopes.co.uk/acatalog/Meade_Series_4000_56mm_Super_Plossl_Eyepiece_2_.html  (36x)

That's why owners of Schmidt-Cassegrains outfit them with a 2" visual-back, for the lowest powers.

At the moderate-to-high powers, the 1.25" format is generally preferred.

An 8mm ocular will give a power of 250x...

http://www.365astronomy.com/8mm-the-planetary-uwa-eyepiece-58-degrees-1.25.html

You can back off the power a bit with a 9mm...

http://www.365astronomy.com/9mm-the-planetary-uwa-eyepiece-58-degrees-1.25.html (222x)

...if the atmospheric seeing will not permit 250x.  

Or, you can go with a 12mm...

http://www.365astronomy.com/12mm-BST-Explorer-ED-Eyepiece.html (167x)

The Moon and planets show considerable detail at 167x.

You might wonder as to why Schmidts are not equipped with 2" visual-backs there at the factory, when they're new.  The reason is simple...

58ed62d6876cf_8Schmidtprimary.jpg.1c1d1ab2c454d860c50aba80c8a86fb2.jpg  

The hole in the center of a 200mm Schmidt's primary mirror, and through which the light from the object passes, is not 2" in diameter.  It's more like 1.5", and ample for the 1.25" format.  The inside of a Schmidt-Cassegrain...

sct_scope.jpg

But given that extra 0.25" of the hole's diameter, 2" eyepieces can be used to make use of that extra bit, and for the lowest powers and the widest views that 2" oculars can provide with the design.  You won't get the full view of a 2", like you would with a Newtonian or refractor, but you will get more than what a 1.25" 32mm or 40mm ocular can provide, and even lower powers in addition.  It's a compromise, and simply to make a Schmidt more versatile.  As a Schmidt comes from the factory, it is primarily configured for the moderate-to-high powers, and with the 1.25" format.  I think that many users simply stick with the 1.25" format, aside from the more adventurous.

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21 hours ago, Peter Drew said:

An 8mm eyepiece is going to give too high a power for most sky conditions, a 12mm one would see more use.   :icon_biggrin:

http://www.365astronomy.com/12mm-GSO-Plossl-Eyepiece.html

 

Assume this would be a decent first buy? Or other poster has suggested 25mm, 15mm and 8mm options..

 

The 12mm will allow for a close view of the moon but will it also be useful for planets? Or would I also need to buy an 8mm option too?

cheers

jimmy

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On 10/04/2017 at 23:32, Jimmystargazer said:

Hi Dave.. hmm.. but of a variation in costs out there... Would this do?

https://www.amazon.co.uk/gp/aw/d/B007RTTLUW/ref=mp_s_a_1_14?ie=UTF8&qid=1491863412&sr=8-14&pi=AC_SX236_SY340_FMwebp_QL65&keywords=2"+star+diagonal

Or anything else you'd advise?

Cheers.

 

Jimmy

 Can't see that anyone has confirmed that you need either a SCT diagonal, that is one with a screw on attachment to attach to the LX90 or a screw on tube that allows a non SCT diagonal to be fitted. As I recall, the LX90 only comes with one that takes a1 1/4 pushfit diagonal. I think we used a William Optics tube, I had a Nexstar 8se and used the dedicated 2inch diagonal. Both solutions worked well. I preferred the dedicated diagonal because I was short of distance between the rear of the scope. There was a danger the diagonal would fit the mount, thus wrecking alignment.

Anne

 

Edited by Anne S
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6 minutes ago, Anne S said:

 Can't see that anyone has confirmed that you need either a SCT diagonal, that is one with a screw on attachment to attach to the LX90 or a screw on tube that allows a non SCT diagonal to be fitted. As I recall, the LX90 only comes with one that takes a1 1/4 pushfit diagonal. I think we used a William Optics tube, I had a Nexstar 8se and used the dedicated 2inch diagonal. Both solutions worked well. I preferred the dedicated diagonal because I was short of distance between the rear of the scope. There was a danger the diagonal would fit the mount, thus wrecking alignment.

Anne

 

Thanks Anne. I was literally just about to order the diagonal.... I'll wait off and wait till home after work to check the scope.. 

Appreciate your input.

So basically I need to check that the eye tube bit as a screw attachment and need to measure the tube bit too?

Thank you..

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8 hours ago, Alan64 said:

Were you able to determine that you can in fact connect a 2" diagonal to the telescope?  You will need a specialised adaptor to connect one, if one is not already fitted...

https://www.telescopehouse.com/accessories/meade-lx/meade-sct-thread-to-2-adapter.html

The goal of upgrading to the 2" format is in realising the lowest powers with the telescope.  For example, you can insert this 2" 56mm ocular for one of the lowest powers with your telescope...

https://www.harrisontelescopes.co.uk/acatalog/Meade_Series_4000_56mm_Super_Plossl_Eyepiece_2_.html  (36x)

That's why owners of Schmidt-Cassegrains outfit them with a 2" visual-back, for the lowest powers.

At the moderate-to-high powers, the 1.25" format is generally preferred.

An 8mm ocular will give a power of 250x...

http://www.365astronomy.com/8mm-the-planetary-uwa-eyepiece-58-degrees-1.25.html

You can back off the power a bit with a 9mm...

http://www.365astronomy.com/9mm-the-planetary-uwa-eyepiece-58-degrees-1.25.html (222x)

...if the atmospheric seeing will not permit 250x.  

Or, you can go with a 12mm...

http://www.365astronomy.com/12mm-BST-Explorer-ED-Eyepiece.html (167x)

The Moon and planets show considerable detail at 167x.

You might wonder as to why Schmidts are not equipped with 2" visual-backs there at the factory, when they're new.  The reason is simple...

58ed62d6876cf_8Schmidtprimary.jpg.1c1d1ab2c454d860c50aba80c8a86fb2.jpg  

The hole in the center of a 200mm Schmidt's primary mirror, and through which the light from the object passes, is not 2" in diameter.  It's more like 1.5", and ample for the 1.25" format.  The inside of a Schmidt-Cassegrain...

sct_scope.jpg

But given that extra 0.25" of the hole's diameter, 2" eyepieces can be used to make use of that extra bit, and for the lowest powers and the widest views that 2" oculars can provide with the design.  You won't get the full view of a 2", like you would with a Newtonian or refractor, but you will get more than what a 1.25" 32mm or 40mm ocular can provide, and even lower powers in addition.  It's a compromise, and simply to make a Schmidt more versatile.  As a Schmidt comes from the factory, it is primarily configured for the moderate-to-high powers, and with the 1.25" format.  I think that many users simply stick with the 1.25" format, aside from the more adventurous.

Thanks Alan...

Kind of none the wiser of which I need to buy LoL...

Think I need to measure the eye piece aperture and check if it has a screw attachment too before ordering.

You are all GREAT!

Cheers

Jimmy

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20 hours ago, Cosmic Geoff said:

I have a SCT of the same aperture and focal length. I use 25mm, 15mm and 8mm eyepieces with it. All are 1.25". You only want 2" eyepieces for lowest power/widest field as the 1.25" are cheaper and more widely available. Plossl types are good enough at 25mm and 15mm unless you have exacting requirements or deep pockets. I have not invested in any lower power (wider field) or 2" eyepieces as I have other scopes for that.  For my scope the cost of a 2" visual back, 2" diagonal and 2" eyepiece adds up to an off-putting sum. But if you have no other scope you may feel it's worth it.

You will need to get the finder (finders) to work and be accurately aligned before you can proceed to aligning and using the GoTo electronics, as the field of view of the main scope is fairly small. Assuming the hardware works as it should, you will scarcely need the finder once the GoTo is set up, and you should be able to find large numbers of objects.  While GoTo systems differ, there is usually a choice of alignment modes e.g. One Star or Solar System object - quickest and least accurate, Two Star - more accurate , Three Star - most accurate and the most fiddly.

Even if the mount has an equatorial wedge (and corresponding settings in the software) you should get used to using it strictly in alt-azimuth mode (mount base horizontal) first - that may prove challenging enough to start with.:icon_biggrin: The equatorial wedge is principally for astrophotography.

I'm not sure how your Meade is powered, but if it uses internal dry cells, think about getting an external power pack for it soon.

Thanks Geoff..

Just managed to get the LNT module working.. had plugged into the wrong hole... So from set up I had the telrad the wrong was round, so didn't do anything and the LNT plugged into the wrong hole.. So didn't work either.. Got rather frustrated trying to use my phone app to level and find magnetic north at 12.30 am! LoL...

Been cloudy skies since so just waiting for a decent evening to try the telescope out again.. LoL... Learning curve in deed.. the school boy errors don't help.

Thanks for your input.

Jimmy

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On 07/04/2017 at 17:02, Hicks said:

My first scope was an LX90 too, it's a good quality instrument and you can get a lot out of it, you just have to be patient and work through the various challenges.

Collimation

Collimation is important, and you can do a quick star test to get a rough idea of what it is currently like, as mentioned in the post above. I'd be inclined to only check the collimation to try to gauge if it's out or not without trying to improve it initially though. If the inner part of the donut is roughly centered when a star is out of focus, it's likely close enough to make do with for a couple of nights whilst you get used to everything else first. It will also give you a reference point for when you do start to try to improve collimation which is quick to do once you know how (5-10 mins) but can easily end up taking up a few sessions when you're learning.

Cooling

The comment about letting your scope have chance to equalise the temperature with ambient is vital, don't bother trying to collimate until the scope has had an hour or so to equalise.

Alignment

As far as stars for alignment not been visible, do you mean the scope isn't pointing in the correct direction or close enough to them, or that they're blocked by trees/house etc If the latter, you can request the autostar select another star. I forget if it's via pressing mode or the up/down arrow off hand though. It's in the manual either way.

As long as your tripod is roughly level and you put the scope pointing north and have the date/time/location correct, the scope shouldn't be too far away from the target star, although it's unlikely to be in the eyepeice, it should be in the finder or very close.

One tip for pointing the scope north. Center polaris in the eyepeice and then slew the scope in the vertical direction only until it is horizontal (use a spirit level when you're close). That is assuming you're in Alt/Azimuth mode and not using a wedge, check your autostar is correctly configured for that. If it's set to polar and you're not using a wedge you'll run into all kinds of problems.

Focusing can be tricky to do well at first and on some nights if the seeing is poor you'll never really feel like anything is in focus.

Dew Shield

The earlier post about a dew shield, do not ignore that advice. Get an inexpensive 8" flexi shield which should be around £25 (or search the forums for examples of people building their own), it's invaluable.

SCTs will collect dew like there's no tomorrow and once it sets in, that's it, you're done for the night as you can't just wipe it off and even if you heat it to evaporate, prevention is better than cure as deposits can build up on the corrector plate.

I as I imagine most others do, use a dew shield + heater strip. You can avoid the cost of a heater strip for a while, but I would buy a dew shield before anything else, although I'd also consider picking up a star diagonal as well, your back will thank you on that one :)

A first scope is quite the learning curve as you'll be unsure if issues are you or the scope at first. The comment about heading to a astro meetup is a good one. Other than that, try not to get frustrated, a bit of patience and persistence and it'll eventually become second nature and you'll wonder why you ever struggled :)

Thank you for your amazing advice and input..

Lots to take on board but getting an idea of essentials I must buy to get more out of my scope...

Mainly 90° tube, 12mm eyepiece and a few shield...

Cheers.

 

Jimmy

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3 hours ago, Jimmystargazer said:

Thanks Anne. I was literally just about to order the diagonal.... I'll wait off and wait till home after work to check the scope.. 

Appreciate your input.

So basically I need to check that the eye tube bit as a screw attachment and need to measure the tube bit too?

Thank you..

Just have a look at First Light Optics. They show the adapter required for a standard, push fit diagonal. At the back of your LX90 is a screw thread. You won't be able to insert a pushfit diagonal as they are designed to go into a crayford type focuser. You probably had am adapter fitted to allow you use he supplied 1 1/4 diagonal. You will need to replace this adapter to fit a 2 inch diagonal. FLO have standard, push fit diagonals but they also sell the adapter to convert it to a SCT type. Not a bad idea as you can use the diagonal in SCTs as well as refractors. 

Hope that clarifies things.

Anne

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