LX90 LNT - my first thoughts

[Rohan]

Well 2 weeks on and 3 viewing nights under the arm thought i might make a quick post about my thoughts on the LX90.

In terms of viewing last night was supurb, clear skys, no wind at all, light pollution a problem but what can ya do.

Anyway to be honest i'm not very happy with my scope. So far it hasn't impressed me much. My main concern has been the GOTO. The first night it was fine, second night it stuffed up a lot and i had to realign it twice before getting feed up. Last night it took 5 attempts to get a succesful alignment. I checked everything, date, time, location, comfirmed the stars on my computer and it still failed. When it slewed to the alignment stars it wasn't even close to them, often 45+ degrees off. The first night it stopped right on them.

So obviously when i did get it succesfully aligned went for a spin around the universe. Saturn, not in eyepiece, had to aling with the finder. Jupitier, just in the eye peice but still abit dodgy. Then went off hunting galaxies, nebs and so on. Everytime what ever it slewed to looked nothnig like what i was expected. Eventually i just wizzed around looking for something interesting. Came across a bright yellow star and was wondering what it was, used the identify option and autostar came up with the jewal box. Funnily enuf i was no where near the jewal box. Checked the dec and RA locks and they were firm on and the scope had not moved at all.

Told it to GOTO Omega C. and was off again, finally tried Jupiter so i could defianatly check it was off. Got the rough location but still didn't make my finderscope. By then i had had enuf so packed up and went inside.

Unfortunatly the setup of my house & backyard prevent me from been able to focus on anything far away (land objects) so i havn't had a chance to train the drives. Anyone think that will help. I guess i have taken the wrong approach to astronomy by getting a GOTO, if the scope points at something i don't always know if its miles off or i just can't see anything because a) scope to small or b) city lights.

Or maybe i just expected way to much for an 8". So far i'm worried that i may have just spent $3500 on a large paper weight. Will try get out to a dark site in the next few weeks to re-ignite my interest.

[westsky]

Hi Rohan , from my experence with meade goto's you must train the drives, I have converted two of my EQ5 mounts to Meade goto's and had the same problems as you describe this ended after I trained the drives, Don't give up on Goto yet it is a good aid in light polluted sky's

David.

[Striker (Tony)]

Rohan,

That sounds ordinery......Mine has never stuffed up like that...sometimes the first alignment star can be well off but then the second is very close.....and away I go.....very rarely the object wouldn't be in the FOV with most of the time always centered....

Have you tried just holding down enter for a couple of seconds after you have alighned...after the alignment just goto say Saturn and make sure its in the center FOV and hold down the enter button....this will ask you if you want to sync on Saturn just enter again....I only do this if I have accidental bumped the scope and gone out of alignment.

Just try it......

I have been amazed how accurate the LX200 have been....and now its sold...go figure...lol

[trufflehunter (Wayne Robinson)]

Sorry to hear that, Rohan. You and I received our LX90's at about the same time and my experience has been exactly the opposite. Every Go-To has not only been successful, but the object is dead centre in the middle of the field. The tracking is also spot on. I always use a Meade 12mm illuminated reticle ep (167X) to set the alignment stars, and the last time I left the second alignment star, Denebola, on the cross hair while I fiddled around for about 15 minutes. When I came back, Denebola was still right on the cross hair.

No, for me, the tracking and go-to capabilities of the LX90 have far exceeded my expectations to the point of being scarey!

Are you using Automatic Align? I can't use that because, usually, at least one of the alignment stars that Autostar chooses is behind a tree or a building. Therefore I have to use the 'old fashioned' Two Star Alignment. That way I get to choose my own alignment stars and I've been using Alpha Crucis and Regulus (or Denebola) because they're currently about as far apart as I can get. And 'as far apart as you can get' is what you should aim for.

The only disadvantage of Two Star Align is that you must place the scope in it's "Alt-Azimuth Home Position, meaning level the scope (I use a little 'bulls eye' bubble level) and point it due north (yes NORTH, not SOUTH! it doesn't have to be exact, but the closer you get it due north, the closer the scope will slew to the alignment stars). This was the only method available with the Autostar on my previous LX55-AR6, so I'm quite comfortable with it. Except in the older scope you had to enter the date and time every session. At least with the newer ones, the LNT module holds that info, making it easier. And it's ability to hold the date and time is the only advantage offered by the LNT module, in my view!

I actually prefer the Two Star Alignment, not only because I get to choose the alignment stars, but also it's QUICKER! The scope doesn't have to go through it's 'find north' and 'level' routines. I can manually level it, roughly point it north, tell it to do a Two Star Align and have it up and running in less time (and with more surety) than letting it do its own automatic thing!

Just a thought... speaking of date and time... is yours correct? Is your location correctly entered into Autostar?

I hope this helps in some way. I really feel for you. There's nothing worse than having your hopes dashed. But don't give up hope! The LX90 is a magnificent instrument, and 8" of aperture (in reference to the other fear you mentioned) will show you just about everything in the Autostar database, often in breath-taking detail. Try the ideas I mentioned above and see if that works. If not, then there's just something else that needs 'tweaking'.

By the way... if there IS something I don't like about the LX90, then it's the Red Dot Finder. It's a joke. I just pretend it's not there!

[trufflehunter (Wayne Robinson)]

I meant to add... all this is "out of the box". I haven't trained the drives or calibrated the sensors. I haven't needed to! All I've done is added 'bob's knobs', which I'm hoping to use tonight on a star test to get the collimation spot on.

[[1ponders] (Paul)]

I sorry to hear that things aren't happening for you Rohan. Truffle has the right of it when he says the 8" is a great medium-small scope. The depth of field and clarity are fabulous for this particular type of scope. So persevere. If you haven't already done so some things to check are, do you have a daylight saving option, the scope hasn't defaulted back to the Norhtern hemisphere, your RA drive is centered (release the clutch, rotate the forks all the way in one direction, by hand and then rotate back one turn),

David, Tony and Wayn have hit it pretty much on the head. While I have the LX200 the principle is much the same, except the telescope fills in all the latitude, time etc details for me. Certainly train the drives, though I hadn't when I first go my scope and if functioned fine. (for me, then - I'm a little bit more discerning now). Unless I'm going to a new site I usually only use the two star alignment like Wayne, not the Automatic.

I had a similar problem when I aligned on a star after the autostar selected it, slewed to near it and then asked me to center and press enter. I of course centered the wrong star. after completing the alignment autostar still said "alignment successful" Go figure.

If all else fails, and I mean all else, go into your setup menu and reset everything to default. This means you will have to re-input all your user specific information including drive training info, but at least you will be starting with a blank slate so to speak. there are two main benefits of doing this. 1. If you have inputted somthing incorrectly accidentlaly then it will be erased and the new corrected info will then take over. And 2. You will really get to know your setup menu and manual . I've actually reset mine 3 times (once accidentally so that doesn't count) simply for that reason - to get to know the menu items on the autostar.

BTW when Autostar slews to a star during alignment it intentionally doesn't slew directly to the star. It deliberately misaligns, so you hve to guide to the star. I'm not sure I understand why, but I seem to recall something about helping to calibrate the alignment process. Sorry i can't be more specific. I'll try to remember where i heard/read about that and let you know.

Good luck

[Dave47tuc (David)]

Well not much i can add, but to say most problems are user input in the AutoStar mistakes. Easy done..

Meaning (not sure on the new LX90) but you must enter all information correctly.

Get the tripod level, make sure your alignment stars are in the centre of high power eyepiece.

Train drives.Do this in the daytime on a distance object.

Make sure all settings in the AutoStar are correct. For your location.

Good luck it will work very well once set up right.

[Mick (Michael)]

I never use Automatic Align, I use two star alignment and pick my stars this works for me. Do you wait for the beep before centring the alignment star? I've never had any problems with tracking or alignment with my Lx90 in 3 years of use. I hope you can sort things out Rohan, Autostar is a wonderful tool.

[acropolite (Phil)]

Rohan,
I got the latest LX90 in the same shipment. When I do auto alignment, the alignment stars are a couple of degrees out, but once aligned, the goto puts the object at the top right of the view; close enough for now. Sounds like Wayne's method of manual alignment is better. I have yet to correct the Lat/Long which I know is a little out and each time I have aligned I have had metal within a few metres of the scope which would effect it's north sensing. Maybe your LNT module is faulty. My scope was inaccurate out of the box, but I immediately found that Bintel had the wrong date entered and once corrected it performed OK. I had a bit of trouble with the red dot finder but once I got it working correctly I found it really useful. I haven't got anything else to compare with but I'm impressed with the optics so far. Sounds like you have some problems, given that the unit worked fine the first time. I also noticed in one of your other posts, a long DC power cord in the pic, you probably will have a substantial voltage drop over that cable and that could be causing your problems; I would recommend trying it on drycells in the supplied base compartments. If you get some duracells from an office supplies place you should be able to get them for under $1 each. (Meade claim 60 hours to a set but my estimate is more like 6 hours.) That will give you a stable power source for testing and at least eliminate one possibility. Don't fall in to the trap of measuring the voltage on the plug of your cord as this figure is meaningless unless under load. I would also try manual alignment as Wayne suggested, then if it's still faulty give Bintel a call.

[rumples riot]

Several things have sprung to my mind from my own experiences.

First use an illuminated reticle to do your alignment, you will get excellent alignments if you do this (and also do the train the drives and calibrate sensors). Two make sure you have the right stars. It is very easy to make a mistake and use the wrong star. I have done it several times and I have been involved in this hobby most of my life and still don't know all the star names. Three make sure that you set up your scope on solid ground. I cannot emphasis this enough. I once set up on lawn in my parents yard and wondered why the scope would loose lock all the time. Until it dawned on me that the lawn was providing just a little give and this can make a huge error in the sky.

Yes recheck all information in the system and yes check to see if daylight savings is set. That alone will cause the scope to go to the wrong place all the time.

BTW Truffle you can shuffle betweem stars on Automatic. You can shuffle up and down the list at least 6 times before you have to use it star it chooses.

Anyway Rohan good luck, ask more questions if you need, there are plenty of us here that own Meade Fork mounted scopes. I am sure between all of us your scope will doing what it is meant to in no time.

[Rohan]

there is defianatly nothing wrong with my inputs, date is correct, time is correct (DS is off) and my Lat Long are spot on. Still it points off. Prob won't be able to get out again for 4+ days but will try a few different methods when i do.

I use the auto align and use sirrus and canopus as the stars. It choose them but they are also the brightest for me and im 100% sure where they are. I live very close to the city so light pollution is quite bad.

IN regards to viewing, will be dissapointed untill i see something worth it. At the moment all i see is black with a few stars, but at i'm putting that down to the crap GOTOs.

Thanks for all your comments.

[rumples riot]

The two stars it picks could be part of the problem. I found that when I used both Sirius and Canopus in Alt Az mode that the separation between the stars is not far enough apart. Certainly use as your first star then select another star much further away. This will give your scope much greater angular separation and therefore more accuracy with the calculation for setup.

What surface are you setting up on? Like I said grass can be a problem.

Just remember in terms of what you can see in the city, faint objects will be harder to see. A good example for my scope is centaurus A. A side on galaxy is very very faint in my 10" scope. Using averted vision helps a lot and detail can be seen, but your eyes have to be adjusted. Try for Eta Carina, the dust lanes are easily seen and your scope will pick it up. Orion's nebula is also a good one to see. As is the sculptor galaxy (not available for a couple of months). Just remember that you don't have a 18" scope and somethings will not be seen easily.

Anyway tell me more?

[ballaratdragons (Ken)]

Good Grief, do you guys really have to go through those precedures every time you want to use your scope? If it is permanently mounted in an observatory do you still have to do this alignment thing each time?

From what I have read above, I don't think I will ever want GoTo.

[Rohan]

No, if its permanatly mounted when you finish your observing session you select the PARK option. This parks the scope and allows you to turn it off but it retains alignment detials. You only have to align it when you move the scope.

[ballaratdragons (Ken)]

Thanks Rohan, It was really turning me of wanting GoTo. When the time comes for me to get a decent Goto it will be permenently housed.

[Rohan]

and forgot to say earlier that the power supply i use is one bintel supplied me, the cords are quite long so maybe its losing abit of power. Might do a run with batteries one night.

[acropolite (Phil)]

Ken, you can push the meade around just like a dob if that's your wish. The auto align (using sirius and canopus which at 42 south are almost overhead) takes only a couple of minutes and has been accurate enough on my LX without training. The long cord thing is critical Rohan, most people simply don't realise how heavy cables should be at 12 volts. I used to be a solar dealer and saw many cases where excessive resistance in 12 volt cables caused 12volt flouros to burn out. The cure was always the same, usually 6mm sq cable. If you've got say 4 x 15W 12volt flouros you've got just on 6 amps of current. Just 0.5 ohm of resistance and you've lost 3 volts and given that 12 Volt flouros don't work below 10.5 volts you can imagine the consequences.

[Rohan]

sorry acropolite, im not an electrician so all that doesnt mean much to me. I do get the long cord = bad thou.

[ballaratdragons (Ken)]

Originally posted by acropolite
Ken, you can push the meade around just like a dob if that's your wish.

Nah, when I get a GoTo I'll use the computer to do the work. I'll still keep the Dob for push/pulling around the sky.

What I really want is a huge reflector GoTo. Bit worried about keeping a corrector plate clean.

[acropolite (Phil)]

have a new found respect for you dobbers, how you get there in the first place amazes me and you must keep nudging all the time to keep your target.