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ArieSirius123
super member


Reged: 12/10/10

Loc: wesley chapel, FL
meade ds-90
      #4276496 - 12/28/10 02:59 PM

anyone ever use one of these?

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artao
super member


Reged: 10/06/10

Loc: SW Wisconsin
Re: meade ds-90 new [Re: ArieSirius123]
      #4276519 - 12/28/10 03:11 PM

I have one, if your talking about a 90mm f/11.1 (1000mm) refractor on a GOTO mount with a model 494 hand controller.
I found mine in the garbage, with neither eyepieces nor power supply. The mount and focusser needed a little TLC, I borrowed eyepieces for a few years and have now bought my own, and use one of those all-in-one AC adapters for power. I also had to modify (well, replace) the EP holder to take 1.25" EPs.
Perfectly useable scope! I have seen wonders galore using it, and know it will continue to give me joy for years to come.
It's VERY important to get good alignment to use the GOTO I've found. There's a couple degrees of play in both altitude and azimuth that I can't seem to get rid of. The focusser works, but needs improvement or, preferably, replacement. I'd also like to upgrade to a 495 or 497 hand controller, to make it easier to hook my computer up to the scope. The finder scope completely sucks, but is "useable". I must replace that, sooner than later.
I've used it a little for astrophotography even, mostly limited by my *BLEEP* web-cam. Just the Moon and Jupiter so far.
Anything else you wanted to know?

EDIT : seriously? bleeped for that word, started with a 'c'?

Edited by artao (12/29/10 01:07 AM)


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scott m
sage
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Reged: 12/06/07

Loc: Hatfield Pa
Re: meade ds-90 new [Re: artao]
      #4276527 - 12/28/10 03:18 PM

I have two of them; optically they are pretty good. I did replace the focuser with a metal rack and pinion from Meridian versus that plastic thing they put in. I also mounted mine on a Orion AstroView.

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ArieSirius123
super member


Reged: 12/10/10

Loc: wesley chapel, FL
Re: meade ds-90 new [Re: scott m]
      #4276782 - 12/28/10 05:34 PM

thanks. actually i did want to know a little more about it. like...how much did these cost new? also whats the process like to align it so that the goto works. also can you just use it like a point and shoot if you dont want to use the computer. thanks a bunch

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sg6
professor emeritus


Reged: 02/14/10

Loc: Norfolk, UK.
Re: meade ds-90 new [Re: ArieSirius123]
      #4276862 - 12/28/10 06:19 PM

You can use it without doing the goto setup, I assume that it will be powered up so in that case point it north to start with. That way the motors will be driving it more or less correctly when it is simply tracking whatever object you find.

If I cannot be bothered with the alignment I simply level the scope, point north and tell it to do the easy align and simply say OK when the scope stops at what may or may not be the 2 alignmnet stars.

At least then when I drive it to something the scope tracks fairly well so the viewing is longer before adjustment is needed.


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ArieSirius123
super member


Reged: 12/10/10

Loc: wesley chapel, FL
Re: meade ds-90 new [Re: sg6]
      #4277052 - 12/28/10 08:10 PM

i think im going to buy a used one that apparently hasnt been used (i know that sounds funny). gonna go check it out next week.

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artao
super member


Reged: 10/06/10

Loc: SW Wisconsin
Re: meade ds-90 new [Re: ArieSirius123]
      #4277494 - 12/29/10 01:01 AM

Can't say what they were (are) new, but when I found mine and looked it up on eBay, I saw a couple for around $250, including eyepieces and the power cord (DC I think)
Alignment.
First off, it's important to have the scope balanced decently. I like to have mine slightly front-heavy as opposed to neutral for a more positive drive engagement. My observation is that I get better tracking that way and the eyepiece stays at a more comfortable viewing height. You also need to calibrate and train the motors, which is a fairly simple process.
It may go without saying, but I've found that to rarely be true, so ... You've also gotta have your Lat./Long., date, and time entered accurately.
Once you've got that, it's rather simple. I always do the two-star when I actually align.
I pick two stars with quite different sky locations. Say one at least 65 degrees high, and another closer to 20 or so, and at least 100 degrees east or west of the first star. I'll align on the two stars, then tell the scope to slew to Polaris. If it's too far off, I re-do the alignment. If it's ok, I slew to some other bright star, then hold down the 'Enter' button to put it into 'correction' mode (that's not what it's actually called, sorry). This turns off tracking temporarily, and asks you to center the object, then hit 'Enter' again. Basically, it corrects GOTO and/or tracking errors a bit. I often repeat this on different stars, GOTO-ing them, until I'm happy with how centered the requested object is. Usually doesn't take more than 2 tries, tho I've had to do up to 5.
Using this process, I have left the scope tracking, unattended, for up to 4 hours and come back to find the object still in the eyepiece.
Sometimes I just use it un-powered for simple Lunar or planetary viewing. Other times I power it but don't bother with alignment. Quite nice so you can use the handbox to move the scope instead of trying to nudge it around by hand.
If the scope's in decent condition and a good price, GO FOR IT!! You'll be pleased I think.


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ArieSirius123
super member


Reged: 12/10/10

Loc: wesley chapel, FL
Re: meade ds-90 new [Re: artao]
      #4277533 - 12/29/10 01:50 AM

how nice. its apparently like new, "not used" was the exact wording. spoke to the lady who seemed to not have a clue or an interest in what she had. 100 bucks.

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ArieSirius123
super member


Reged: 12/10/10

Loc: wesley chapel, FL
Re: meade ds-90 new [Re: ArieSirius123]
      #4277600 - 12/29/10 03:47 AM

i was just reading about the thing only accepting .965 eyepieces?! thats no bueno,..right? its the ds90-at

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StarStuff1
Post Laureate
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Reged: 04/01/07

Loc: South of the Mason-Dixon Line
Re: meade ds-90 new [Re: ArieSirius123]
      #4277627 - 12/29/10 04:50 AM

If it is new and only $100 it is hard to go too much wrong. I paid $125 plus shpg a few years ago for the same package without an OTA.

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ArieSirius123
super member


Reged: 12/10/10

Loc: wesley chapel, FL
Re: meade ds-90 new [Re: StarStuff1]
      #4277638 - 12/29/10 05:20 AM

does anyone know whether it accepts 1.25 eyepieces. the ds90-at

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artao
super member


Reged: 10/06/10

Loc: SW Wisconsin
Re: meade ds-90 new [Re: ArieSirius123]
      #4278288 - 12/29/10 01:47 PM

did a quick search. looks like some came with .965" an some came with 1.25". Mine took .965", but I used an old vitamin bottle that just so happened to fit the draw-tube AND have an appropriately sized neck ..
and looky looky what I found, from the cloudy nights archive LOLz
http://www.cloudynights.com/ubbarchive/showflat.php/Cat/0/Number/193378/page/173/view/collapsed/sb/2/o/all

EDIT: unfortunately, the links in the forum don't appear to work anymore

Edited by artao (12/29/10 01:48 PM)


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ArieSirius123
super member


Reged: 12/10/10

Loc: wesley chapel, FL
Re: meade ds-90 new [Re: artao]
      #4278484 - 12/29/10 03:35 PM

if it does come with the .965 eyepieces, would this help.....

http://cgi.ebay.com/Antares-0-965-1-25-90-degree-Hybrid-Mirror-Diagonal_W0QQitemZ110610320625QQcategoryZ74925QQcmdZViewItemQQ_trksidZp5197.m7QQ_trkparmsZalgo%3DLVI%26itu%3DUCI%26otn%3D5%26po%3DLVI%26ps%3D63%26clkid%3D5998085588747612791#ht_3517wt_851


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artao
super member


Reged: 10/06/10

Loc: SW Wisconsin
Re: meade ds-90 new [Re: ArieSirius123]
      #4287354 - 01/02/11 06:02 PM

Sorry it took me a few days to get around to this. Here's those pics you requested of my scope.
The long narrow tube across the top is my initial attempt to make a camera mount for the scope. It is currently under re-consideration and re-construction.

Angle #1:

===================================='

Angle #2:

====================================

My modification to accept 1.25" eyepieces:

====================================

I added this bubble level from the local hardware store too:

====================================

Hope that helps, or is at least interesting.


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artao
super member


Reged: 10/06/10

Loc: SW Wisconsin
Re: meade ds-90 new [Re: artao]
      #4287359 - 01/02/11 06:04 PM

Also, the black rectangles on the legs are strips of velcro. I put matching velcro on the back of the handbox, and thus can quickly stow the handbox on any leg of the tripod.
Any other questions, feel free to ask.


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rdandrea
Carpal Tunnel
*****

Reged: 06/13/10

Loc: Colorado, USA DM59ra
Re: meade ds-90 new [Re: artao]
      #4287372 - 01/02/11 06:08 PM

Why not just bolt a standard accessory dovetail to the rings and attach a ball head for your camera?

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artao
super member


Reged: 10/06/10

Loc: SW Wisconsin
Re: meade ds-90 new [Re: rdandrea]
      #4287948 - 01/02/11 10:44 PM

Well, for one thing I don't have one and can't afford one right now. But also because the set-up is meant for eyepiece projection photography.

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rdandrea
Carpal Tunnel
*****

Reged: 06/13/10

Loc: Colorado, USA DM59ra
Re: meade ds-90 new [Re: artao]
      #4288554 - 01/03/11 10:27 AM

Ahh, I wasn't clear on what you were doing. I was thinking piggy-back.

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ArieSirius123
super member


Reged: 12/10/10

Loc: wesley chapel, FL
Re: meade ds-90 new [Re: rdandrea]
      #4290439 - 01/04/11 12:52 AM

i just got mine today. i also had "first light". i saw a very tiny jupiter with no details on it, basically a white orb, it was cool to see the moons around it tho. really cool although i was expecting a cloud band. really dark sky too. maybe its the junk .965 eyepieces that im going to replace immediately. anyway, i couldnt really make the goto work, but the motor is strong that much is clear. with some more practice ill get it soon enough im sure.

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artao
super member


Reged: 10/06/10

Loc: SW Wisconsin
Re: meade ds-90 new [Re: ArieSirius123]
      #4294483 - 01/05/11 06:31 PM

I've had excellent views of Jupiter with mine, but with decent eyepieces. I've been able to crank this scope up to 220x on the moon, and I was mostly happy with the view. even 330x worked, but the views were far fuzzier.
of course, seeing was EXCELLENT that night. I've looked at Jupiter up to 220x as well.


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Terike
journeyman


Reged: 01/01/11

Re: meade ds-90 new [Re: artao]
      #4294936 - 01/05/11 09:40 PM

I have the same scope and mount setup as you. Though I have a diagonal eyepiece converter to 1.25.

I will be trying to control from the computer very soon. Have you had any problems or do you have any advice that might help me setting it up for my first time?


Clear skies!


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ArieSirius123
super member


Reged: 12/10/10

Loc: wesley chapel, FL
Re: meade ds-90 new [Re: Terike]
      #4294942 - 01/05/11 09:44 PM

best advice is to read the manual for the autostar really. not too difficult to understand after you read it over some.

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ArieSirius123
super member


Reged: 12/10/10

Loc: wesley chapel, FL
Re: meade ds-90 new [Re: artao]
      #4301755 - 01/09/11 01:08 AM

i just wanted to report on this telescope seeing as tonight was the first time i really was able to get it accurately aligned with the goto. i was able to enter anything in the handset and the telescope would find it, and track it, dead on. optics were pretty good too. not as good as a 12 inch dob but pretty damn good for a 90mm refractor. overally very pleased with this telescope. looking forward to getting a 1.25 inch stepback.

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zvaragabor
member


Reged: 01/25/11

Re: meade ds-90 new [Re: artao]
      #4340839 - 01/26/11 05:52 AM

Hi all, I'm thinking of buying a second-hand DS-90. If the objective len is in perfect condition, does it worth a buy? How does it perform compared to a SW or a Cel 90/900? And could someone tell me what's the tube diameter at the focuser end? I've read some comments about the poor focuser design, and that everyone recommends a focuser change, so just to know which size fits in. Any answer would be appreciated. Thanks!

Cheers,
Gábor


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scott m
sage
*****

Reged: 12/06/07

Loc: Hatfield Pa
Re: meade ds-90 new [Re: zvaragabor]
      #4341121 - 01/26/11 09:53 AM

Don't know how it compares to the SW or Celestron but a 86mm focuser fits. I replaced the one on mine with a metal R&P from Meridian.

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zvaragabor
member


Reged: 01/25/11

Re: meade ds-90 new [Re: scott m]
      #4341145 - 01/26/11 10:06 AM

Thanks scott. You use this scope right? Are you satisfied with it? I'm mostly interested in its optical performance.

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ArieSirius123
super member


Reged: 12/10/10

Loc: wesley chapel, FL
Re: meade ds-90 new [Re: zvaragabor]
      #4341346 - 01/26/11 12:00 PM

i have one. its my first scope and i can say that it compares quite nicely to much more expensive scopes ive looked through at star parties. apparently some of them came with .965 eyepiece and some didnt. mine did. and im yet to replace them and even with those eyepieces ive got some awesome views. the goto works pretty good too.

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scott m
sage
*****

Reged: 12/06/07

Loc: Hatfield Pa
Re: meade ds-90 new [Re: ArieSirius123]
      #4341611 - 01/26/11 01:51 PM

Optically it's great very little CA on planets and I think I have had my best views of M42 and the double cluster through this scope.

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sailor70623
Post Laureate
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Reged: 01/12/08

Loc: Ok.
Re: meade ds-90 new [Re: artao]
      #4341703 - 01/26/11 02:29 PM

The scope as far as f11 achros goes is fine. Focuser upgrades can help it out a lot. The DS Go-To can work good, but is a bit weak. Make sure it works before you buy. Balance is very important with these units. They do eat batteries. I use my DS Go-Tos with a 12v to 9v adapter and run them off a deep cycle marine 12v battery. The iOptron mounts work a bit better, and the Se mounts from Celestron are much better, but a good working DS mount can be a lot of fun. If you up grade the mount later, these mounts the DS) hold the smaller 60mm scopes just fine. (80mm short tubes too). I have even used them for my 90mm Maks and they work well then too.
The guts on the DS mounts are plastic, and they do break easily. Depending on how much of a DYIer you are, repairs are possible, but not easy. The biggest fown side is that you need power with these mounts. When the batteries are dead, they do not work. Alignment and training and calibration are importabt with these mounts. It can be a challenge for beginners. Once you get the steps down, it's not so bad.


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zvaragabor
member


Reged: 01/25/11

Re: meade ds-90 new [Re: sailor70623]
      #4341904 - 01/26/11 03:34 PM

Thx guys. Sailor, sorry I forgot to mention, it's just the tube I'd like to buy. And the mound would be an eq3. Thank you anyway, useful advice.

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sailor70623
Post Laureate
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Reged: 01/12/08

Loc: Ok.
Re: meade ds-90 new [Re: zvaragabor]
      #4341912 - 01/26/11 03:36 PM

Then if it's a good price, go for it.

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scott m
sage
*****

Reged: 12/06/07

Loc: Hatfield Pa
Re: meade ds-90 new [Re: zvaragabor]
      #4342216 - 01/26/11 05:42 PM

I have mine mounted on an EQ3 (Orion AstroView) a little shaky at high power but not bad. I think it has to do with the length of the scope versus the weight of it.

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zvaragabor
member


Reged: 01/25/11

Re: meade ds-90 new [Re: scott m]
      #4344374 - 01/27/11 03:44 PM

Bad news, I was late, unfortunately someone took the telescope. Now looking for another scope... Thanks for all the help.
Cheers


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wagner lip
sage


Reged: 01/12/11

Re: meade ds-90 new [Re: zvaragabor]
      #4347358 - 01/28/11 08:19 PM

Last week I bought a DS-90 with the Autostar #494, diagonal and eyepieces are 1.25". I went to pick it up with the seller almost 3 hours from home here in Florida.

I disassembled everything, cleanned everything with warm soappy water and soft brush and cloth as it should. No kidding, disassembled even the main lenses and the guts of the 9mm eyepiece that came along, with extra care, distiled water with small quantity of windex. Fingerprints on the lenses are not a good thing, but I was able to clean everything without compromising the coatings. Ended up pristine clean.

Believe of not, the mount legs were never extended.

The #492 motors units (gears, shafts, photosensor) went through a special care, wash and clean up. Everything was in good shape, but mechanically out of alignment everywhere.

Replaced some washers and nylon retaining nuts on the worm/gear units with brand new ones from Ace Hardware, now they are working like a violin.

I noticed that some people complain about large backlash on DS motors, the problem is mostly adjustment on the worm/gear pressure and worm axial slack movement, easily reduced by the nylon retaining nut adjusment. The worm shaft has a type of conical slug in the opposite side of the nut, if the nut is not correctly tied, the conical slug doesn't go correctly into his bed and the worm ends up with larger distance from the gear... large backlash.

There is a mechanism to fine adjust the distance from the worm to the gear, it is at the nut side of the worm's shaft. It is a kind of bed elevator for the shaft, in the form of a black nylon nut, it pulls the worm's shaft against the gear, adjusted by a tiny alen screw locked by a small nut at 90 degrees to the shaft. The adjustment should be done only after everything else is adjusted (mostly the conical slug in the correct place) and lubed.

A common mistake is to apply grease in the clutch, between the gear and the large locking washers on each side of it. If you do, you will need to apply more force on the knobs to lock the scope (clutch) to the motors. Just wash the gear and the washers in warm or hot soappy water to remove any grease, use a toothbrush to help. After dry, apply a narrow white lithium grease on the gear teeth band and over the worm and that's it. You can apply lithium grease on the support plastic bearings of the worm shaft.

The DS-90 tube is heavy, large mass, the #492 motors are not that strong for this brute, lacks muscle, so tube balance should be pristine. Because of the mass of the scope, the motors will consume more power than most of the other DS scopes. For that I don't use regular AA batteries. I use a power adapter (12V @ 2A) or a 12V@7A Powersonic Lead Sealed battery underneath the mount, or tied to a tripod leg.

Found the plastic encasing the worm/gear underneath the mount base with 3 to 4mm of slack to the base (horrible backlash), like if it was with loosen screews, even so the 3 screws that hold it underneath the mount base where tied. Removed everything, clean, glued a thin silicon band (rubber band should do the trick) in the grove (on the plastic case) that touches the underneath of the mount base. Upon assembly it is now solid. It should had a "O-Ring" or some grooves to avoid it being only hold the plastic case by the tiny screws. With the constant force of the motors back and forth, and friction, the screws openned a wider hole in the plastic, causing the problem. The silicon/rubber band will solve it for years.

The Autostar Computer Controller #494 was telling me some motor problems upon power up. Google told me it could be several things, including bad connection on the coiled cable. Measuring continuity between the RJ31 connector and the inside connector of the #494, found the green wire (pin #4 or #5 on the RJ31) with no contact. Just use the RJ45 crimp tool to recrimp the RJ31, and bam! working like a charm.

The output gear of one #492 motor has one tooth with a small damage. From time to time it skips a step. I am already shopping for a gear replacement. As a matter of fact I am requesting 2 extra #492 motors for safe future, Meade is not manufacturing those any longer.

The DS-90 has fantastic optics, simple, clean, clear and easy, nice light. The viewpiece of 9mm gives around 110x magnification, you can see an orange vertical band on Jupiter, and Saturn is like a little white bird sliding in the black sky, will be stuck in my mind forever.

Aperture of 90mm (3.5") is not that much, but make wonders. This kind of scope really needs a TELRAD urgently. The viewscope that comes with it is a total waste of time.

The AutoStar unit works very well in this unit.

You *MUST* setup the AutoStar controller with your correct Lat/Long (or city), and perfect Date/Time (and DayLight Savings info). Date and Time is required at each power off/on.

Then you need to do the inicial physical setup, very nice horizontal alignment with the tripod and scope. Use a couple of good round (360 degrees) bubble levels, one for the mount and legs, another for the scope itself, then point everything (horizontally) the best you can to the sideral north. Then proceed with the two stars alignment. After that, things works very nice most of the time.

The original focuser has some small vertical slack, but not a problem if you use the #494 and motors to fine adjustment of position.

I have severe back pain. It seems that all refractor scopes are no good for people like me. As the pivot point of the mount goes in the middle of this 40 inches scope, any lateral or vertical move will require you to do the same on the eyepiece. After 90 minutes of playing outside, my back was killing me. I am not that athletic anymore.

I will hate to depart from this DS-90 unit, but it seems the obvious path for my back sake.

The DS-90 is an impressive unit, it is not small, it has personallity and size. People look at it and say "wowa, for sure this is not a toy".

This week I was able to find a ETX-90EC with lots of bells and whistles. With much less movement on my side, my back is already thanking me.

Of course I am still waiting HayNeedle to deliver the second box of my brand new CPC800. The scope itself is in the box here waiting the mount and power bucket that are on backorder from Celestron.

In some way I need two scopes, this way I am trying to have my teen-18-ager boy along me on those Saturday cold nights. Yeah right! At least after he returns home late night!

Edited by wagner lip (01/28/11 08:20 PM)


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rdandrea
Carpal Tunnel
*****

Reged: 06/13/10

Loc: Colorado, USA DM59ra
Re: meade ds-90 new [Re: wagner lip]
      #4347386 - 01/28/11 08:39 PM

Good, thorough post. Thank you.

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mexjon
Poet Laureate
*****

Reged: 12/01/10

Loc: Florida - Yucatan, Mexico
Re: meade ds-90 new [Re: wagner lip]
      #4347439 - 01/28/11 09:14 PM

Wagner- Very informative post! Now that you have that ETX90 EC, make sure you do the same good cleaning job to the right friction clutch so yours doesn't end up broken like mine. Apparently previous owner(s) had over-tightened instead of cleaning and sanding the right tube adapter as they should have. Probably had a lot of grease preventing friction, and they just kept tightening away. By the time I got it, most of the damage was done and it soon broke on both sides of the clutch.

Thanks for your thorough report on your DS. I enjoyed learning about it.

Cheers


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wagner lip
sage


Reged: 01/12/11

Re: meade ds-90 new [Re: mexjon]
      #4353350 - 01/31/11 02:56 PM

John, yesterday I disassembled the ETC90-EC, clean, sand, adjust, lube. It was a nice task. I am posting the work in a new thread, including some pictures of the fork motor noise reduction trick and sealed lead acid battery support.

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mexjon
Poet Laureate
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Reged: 12/01/10

Loc: Florida - Yucatan, Mexico
Re: meade ds-90 new [Re: wagner lip]
      #4353403 - 01/31/11 03:23 PM

Quote:

John, yesterday I disassembled the ETC90-EC, clean, sand, adjust, lube. It was a nice task. I am posting the work in a new thread, including some pictures of the fork motor noise reduction trick and sealed lead acid battery support.




Very good. Avoiding a major problem by getting all that done. Hope you enjoy it.


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artao
super member


Reged: 10/06/10

Loc: SW Wisconsin
Re: meade ds-90 new [Re: mexjon]
      #4355021 - 02/01/11 07:53 AM

@Wagner -- thanks for all that info, i'll have to take mine apart and check those adjustments. I do have a backlash problem on both axes, which seems to exist IN the mount, not the gearpack. I've read of "the leather washer fix", but am having difficulty re-locating that info. Do you, or anyone one else, know anything about this??
Also, regarding your disassembly and cleaning of the main optics ... how difficult was it to maintain collimation? Is the lens assembly sensitive to rotational collimation as well?


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mexjon
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Reged: 12/01/10

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Re: meade ds-90 new [Re: artao]
      #4355937 - 02/01/11 03:27 PM

Quote:

@Wagner -- thanks for all that info, i'll have to take mine apart and check those adjustments. I do have a backlash problem on both axes, which seems to exist IN the mount, not the gearpack. I've read of "the leather washer fix", but am having difficulty re-locating that info. Do you, or anyone one else, know anything about this??
Also, regarding your disassembly and cleaning of the main optics ... how difficult was it to maintain collimation? Is the lens assembly sensitive to rotational collimation as well?





I read on Google that the leather washer info is on the Yahoo DS Group.


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wagner lip
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Reged: 01/12/11

Re: meade ds-90 new [Re: artao]
      #4356493 - 02/01/11 07:09 PM Attachment (31 downloads)

Artao, I removed 3 screws on the front DS-90 lens black lens tube, it came out with lenses.

Put some pencil marks on the black plastic lens tube and white tube.

Then with small force I was able to unscrew a large ring in front of the lenses. This ring hold the two lenses in place.

Now slowly I insert a clean microfibre cloth inside and against the lenses, turn it upside down and "pourred" the two lenses over my hand, marking each lens in the border with pencil (Lens #1 arrow to front, up, same for lens #2).

For a more permanent marks you can use the "house owner's" nail polisher (at the edge of the lenses) and wait it to dry.

After cleanning the lenses very well (distiled water, few drops of windex, I use microfibre cloth, clean perfectly), observe the lenses against a strong light, initially it is never clean. Be carefull to not clean the pencil marks.

Then wait it to be really dry and here comes the tricky part, holding the lenses together and insert it back into the lens tube.

After you find it out, it is easy. Use a clean cloth (microfiber) over the top open of a regular tall water drinking glass and deposit the lenses aligned over the cloth, over the glass. The glass will serve as a temporary tall support, and it must have a smaller diameter than the lenses.

Now slowly cover the lenses with the black plastic lenses tube, following the alignment marks done previously by pencil.

After the tube is down in place, hold everything together, tube, lenses, cloth and cup with some pressure, and turn it upside down, remove the glass cup and cloth, screw back the large front black plastic ring.

Insert all the unit in front of the telescope tube, align with marks, with holes, screws. That's it. There is no ajustments to be done.


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ducatirob
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Reged: 06/15/05

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Re: meade ds-90 new [Re: artao]
      #4357351 - 02/02/11 04:19 AM

Here's the web address showing the leather washer fix; http://jjacobso0.tripod.com/themeadeds90ec/id4.html
I've owned my DS 90 for around 10 years. It Still gets alot use, Hpoe this helps you.
Rob


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artao
super member


Reged: 10/06/10

Loc: SW Wisconsin
Re: meade ds-90 new [Re: ducatirob]
      #4357794 - 02/02/11 10:51 AM

Thank you all three for the info. I had tried googling, but only found references to the washer fix, not the actual "how-to", and my older links were mostly broken ... I eventually found the link ducatirob posted.
@wagner - Very Thank You! for the in-depth description. My optics could use some TLC, but I've been kinda afraid of screwing them up ... this is my only scope, so I don't want to destroy it, obviously ... I've got a lens-cleaning kit, including lens-solution and disposable lens-paper, as well as a microfiber cloth, that I can use. It's just that condensation has left various dirt spots on the lenses where I'd have to take 'em apart to get to.
Now I'm not quite so scared


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ArieSirius123
super member


Reged: 12/10/10

Loc: wesley chapel, FL
Re: meade ds-90 new [Re: artao]
      #4359862 - 02/03/11 03:30 AM

good link ducatirob, was able to fix the clamp on one of the legs. thanks.

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zvaragabor
member


Reged: 01/25/11

Re: meade ds-90 new [Re: ArieSirius123]
      #5545300 - 11/29/12 10:48 AM

Do anyone know the inside diameter for the tube? Or could someone measure it?
Thanks!

Edited by zvaragabor (11/29/12 11:32 AM)


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zvaragabor
member


Reged: 01/25/11

Re: meade ds-90 new [Re: zvaragabor]
      #5644258 - 01/26/13 11:44 AM

Finally I managed to buy a second-hand Meade ds-90 OTA. I'm so happy! It will be my double-star hunter. I found that the only coated side of the lens is the concave len. Is that the case with eveyone else's ds-90?

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