Meade ETX-70AT / Autostar

Agonist

Popoutman wrote: »

I got a set of plossl eyepieces from an ebay shop (OpticalOverstock) - http://url.ie/4poq for about €60, with 32mm, 12mm, 6mm focal lengths, and a neutral density moon filter.

Thanks for your very helpful reply! I'll definitely get these.

I also got a Lumicon UHC filter - this really does make a difference to looking at the brighter nebulae up there.

Great, I wasn't sure that such a thing was available for the ETX -70. I'll try it without the extender for the moment.

Another upgrade I did was to get a Meade #497 classic controller with the full keypad. I got lucky and found one online for about $70 shipped - I made the cable to connect to a PC serial port, and I now have an updated 4.3 revision with the ability to directly key in NGC and IC numbers, and better tours. I can also control the scope from the laptop when I have my webcam in the eyepiece.

I'm not entirely sure what this means. When I looked for the data cable to connect the telescope to my laptop it seemed like they are all serial cables. I don't have a serial port on my PC. I'd like to upgrade the software/firmware for a start.
I'm looking into having a go at astrophotography but I think I'll wait until I buy my next camera before I buy the accessories I'll need.

It would also be useful to get a flexible focuser extension, helps when fine focusing and when the tube is pointing closer to the vertical.

Yes, I've seen these online and I think I'll get one while I'm buying the eyepieces.
I'll stick with using regular batteries for the moment. It's been too cold to stay out for long this winter so I've only gone through a couple of sets.

I'm in the process of using a powerpack battery to power the scope instead of the AA batteries - I went through 4 sets over the past month in the cold weather and daytime testing.

Thanks a million for the info

Popoutman

Agonist wrote: »

I'm not entirely sure what this means. When I looked for the data cable to connect the telescope to my laptop it seemed like they are all serial cables. I don't have a serial port on my PC. I'd like to upgrade the software/firmware for a start.

The ETX #495 handset use the i2c communications protocol, and all serial ports on PCs use RS232 (standard serial).
The #497 handset will interface with a PC with a simple 3-wire cable and the correct socket types, and can be built by someone with a little bit of soldering experience.
However, the #495 handset needs an i2c<->serial converter and Meade package this as the #506 cable, which is usually about €40 or so. You'd be better off getting a #497 and a cheap cable than getting the #506 cable.
Two biggest advantages of being able to update from the PC to the handset is to be able to put in new objects, and to update the firmware. There is no new firmware for the #495 handset.

Agonist wrote: »

I'm looking into having a go at astrophotography but I think I'll wait until I buy my next camera before I buy the accessories I'll need.

The mount and drive components in the ETX-70 are probably not good enough for anything more than webcam on planets/moon/bright double stars. I see too much slow wandering and vibration of the objects in the view, while fine for visual observation even at higher powers, just isn't good enough for photos longer than a few seconds. I have got reasonable results from stacking webcam images of Jupiter over the past while
If you can put the ETX on a wedge and convert it to an equatorial fork instead of its standard alt-az fork, then you can piggy-back a DSLR on top for many-minute driven photos of starfields.
If your drive is smooth and consistent, you may be able to take e.g .30 second exposures of brighter nebulae and stack them for reasonable results.

Popoutman

I attached the felxi-focus thing I got from the Bay, and to be honest it was crap. The cable that was used to construct the focuser extension has a bend from storage and shipping, and it kept 'falling' and twisting the focus away from where I needed it to be. Back to the standard knob!

dbran

Hi Popoutman

I presume that you mean the #494 handset which is the one that comes with the ETX 70 ie without the numerical keypad. Not alone is there no firmware but there is no safeload facility, making it is risky to do anything with the software in case you accidently corrupt it.

The #495 autostar, (I believe) is essentially the same as as the #497 and just needs the software to be upgraded to make it into a #497.

Kind Regards

dbran

Popoutman

Dbran,
Indeed you are correct, i should have been referring to the #494 handset as the one that uses i2c instead of the standard serial protocols.

Thanks for pointing that out.

djhaxman

Hi all, am just looking to pick some brains here.

Has anyone ever seen the above error on their scope? I have the LXD75 with autostar and when I go to auto align the scope, before it slews to the first star it comes up with the error. I thought it was the battery pack running down, but got a power supply, but no joy. The mount is set up correctly, and I always align to polar north manually, so any help on this would be greatly appreciated!

dbran

Hi

First off I do not have an LxD75 (I have an LX90) so I dont know the specifics of your mount.

However I believe the check mount error arises when either
1) the max elevation setting is on or
2) to stop the mount slewing to somewhere dangerous ie it thinks it might topple over if it slews there etc.

You may be picking alignment stars that are too low and the scope is saying no way.

If you press goto I believe it will continue to the allignment star. You should also check to ensure you have set up the mount correctly.

Try reselecting your telescope' s mount on your autostar. Alternatively try a reset which will return it to factory settings and this might do the trick.

Hope this helps.

dbran

djhaxman

dbran wrote: »

Hi

First off I do not have an LxD75 (I have an LX90) so I dont know the specifics of your mount.

However I believe the check mount error arises when either
1) the max elevation setting is on or
2) to stop the mount slewing to somewhere dangerous ie it thinks it might topple over if it slews there etc.

You may be picking alignment stars that are too low and the scope is saying no way.

If you press goto I believe it will continue to the allignment star. You should also check to ensure you have set up the mount correctly.

Try reselecting your telescope' s mount on your autostar. Alternatively try a reset which will return it to factory settings and this might do the trick.

Hope this helps.

dbran

Cheers for the help but I'm sure it's set up correctly, and this error wasn't always there. The first alignment star it always picks is Capella which is more or less directly overhead, but you are right in saying that it still continues when you press go to. I was using the scope for a couple of hours this evening and had to realign to polaris at one stage as it lost it's bearings. I might try the reset as you suggested.

Thanks for the help and sorry for hijacking the thread

dbran

Hi Djhaxman

I was helping a friend set up his Lxd75 for the first time over the weekend and your check scope error came up on a few occasions.

After making sure the scope was set up right we pressed goto and the scope continued to slew to the alignment stars which we then centered.

The scope actually alligned successfully and the gotos were fine for the night. So I reckon you may be safe enough to just ignore the error if you are sure you have followed all the steps in setting up correctly.

Hope this helps

dbran

djhaxman

dbran wrote: »

Hi Djhaxman

I was helping a friend set up his Lxd75 for the first time over the weekend and your check scope error came up on a few occasions.

After making sure the scope was set up right we pressed goto and the scope continued to slew to the alignment stars which we then centered.

The scope actually alligned successfully and the gotos were fine for the night. So I reckon you may be safe enough to just ignore the error if you are sure you have followed all the steps in setting up correctly.

Hope this helps

dbran

Cheers dbran, but I think you were right - I had a look at it today in daylight and the motor was not sitting on the tripod correctly - the t-shaped handle that is used to hold the two together had loosened so the OTA was not sitting correctly. I think. Haven't had a chance to try it out yet. But it seems like it could be the problem. Thanks for the help!

Is it the N6 from LIDL your friend got? What did you think of it?

dbran

Hi

Yes it was the N6. Not a bad little scope and relatively portable. It set up and alligned very easily once the minor teething problems were dealt with. Gotos were good . Definately a keeper I recon

dbran

Popoutman

Just as a reference, I got myself a little level from Homebase recently and I checked how accurate the button level on the ETX tripod plate was.
Turns out that the inbuilt level is off by about 3 degrees.
I've changed my step-by-step setup and I've started to get much better first gotos.

1. Make sure you have good battery power. I've started using a 12v lead acid battery and it has made a big difference.
2. Level the tripod head, both N/S and E/W. I point one tripod leg towards north, get a rough level N/S with that. I then go E/W with the level, and lengthening the relevant other tripod leg to get the E/W level. I return to N/S and tweak that.
3. Bolt scope to tripod plate.
4. Point roughly north, tighten the Azimuth clutch.
5. Level the tube, using the level or judging by the horizon. I get about 1 degree accuracy there. Tighten the altitude axis.
6. Initialise the scope, making sure that you have already got your Lat/Long accurately entered and the correct time entered.
7. Allow the scope to slew to the first star.
8. Unlock the azimuth and turn the scope by hand until you get the star in line with the scope in left/right. Tighten the azimuth axis. (I've usually got the star at the correct altitude, but my initial north may be off by a little bit.)
9. Loosen the altitude axis and approximately center by hand, and tighten the altitude axis.
10. Center properly in the medium power eyepiece, and try to always go in the same direction for the final movement. I try to always go up and right to the star.
11. Slew to the second star.
12. If the above steps were done accurately, you should find the second alignment star to be in the centre.
13. Enjoy an evening of accurate gotos, and fairly consistent tracking.

I have found the slews to be faster and more accurate after moving from the AA batteries to the sealed lead-acid, probably due to lower voltage drop when doing the dual-axis slews.
Following the above procedure I have pretty much guaranteed that I have a fast setup time and good tracking. It was very surprising to see just how inaccurate the inbuilt level really was.

Agonist

Popoutman wrote: »

I got a set of plossl eyepieces from an ebay shop (OpticalOverstock) - http://url.ie/4poq for about €60, with 32mm, 12mm, 6mm focal lengths, and a neutral density moon filter.

Just an update... I got these plossl eyepieces and they are fantastic! The difference is amazing. I can't stop gazing at Saturn. The wider field of view makes a huge difference. It's only since I got these that I've noticed 'bad seeing' and the air making the image wobble. It's a big step forward from looking at Mars as a fuzzy blob (which was exciting too).

I trained the drives on the scope and it's tracking much better but I don't always level it properly. What I like to do is switch off the tracking and watch the planets/moon creep across the field of view. Any touch or vibration makes the scope shake like crazy so I have to keep it simple.

I've found that settling my camera up on a second tripod and lining it up with the eyepiece takes the best photos of the moon and Saturn. I can't get any success from using a webcam and stacking software. It's next to impossible to focus it. I'm waiting for a few adaptors in the post which might improve things there.

Instead of getting a nebular filter, because I don't think I'll be seeing anything great with this telescope, I've bought a broadband light pollution filter and it should be arriving soon.

The #497 autostar is very expensive so I'm holding out on that until I can find a bargain. Damn all those last minute bidders on Ebay.

Thanks for all your tips here. It's a really rewarding hobby.

Wiggles~

Agonist wrote: »

Just an update... I got these plossl eyepieces and they are fantastic! The difference is amazing. I can't stop gazing at Saturn. The wider field of view makes a huge difference. It's only since I got these that I've noticed 'bad seeing' and the air making the image wobble. It's a big step forward from looking at Mars as a fuzzy blob (which was exciting too).

I trained the drives on the scope and it's tracking much better but I don't always level it properly. What I like to do is switch off the tracking and watch the planets/moon creep across the field of view. Any touch or vibration makes the scope shake like crazy so I have to keep it simple.

I've found that settling my camera up on a second tripod and lining it up with the eyepiece takes the best photos of the moon and Saturn. I can't get any success from using a webcam and stacking software. It's next to impossible to focus it. I'm waiting for a few adaptors in the post which might improve things there.

Instead of getting a nebular filter, because I don't think I'll be seeing anything great with this telescope, I've bought a broadband light pollution filter and it should be arriving soon.

The #497 autostar is very expensive so I'm holding out on that until I can find a bargain. Damn all those last minute bidders on Ebay.

Thanks for all your tips here. It's a really rewarding hobby.

Sorry to bring up this old thread again, but I was just wondering if anyone knows a reliable site still selling this eyepiece set? I've tried Ebay and Amazon but neither seem to stock it anymore. Or if it's not in production if there's a similar set of lenses on sale somewhere in the same price range.

I'm still quite new to astronomy, but i've definitely caught the bug and i'm dying to improve my scope for better viewing of Jupiter and Saturn especially.