Very Impressed with EQ5 duel drive!!!!

[ballaratdragons]

Tonight is finally a sort of clear night (bit foggy).

I can now test the accuracy of the duel drive motors (mainly R.A.) on the EQ5 (with 120mm refractor) I bought for the SVAA.

First off, I cheated with the polar alignment :D

I polar aligned my EQ6. Then I put a peg on the EQ6's green laser to keep it switched on, and polar aligned the EQ5 to the laser :whistle:

Then once the EQ5 was polar aligned I centred Canopus (way down low) in a 9mm EP, and set it tracking.

It has now been 2.5 hours and Canopus is STILL in the centre of the FOV!!!!!!!!! :eyepop:

I must say, those little motors are pretty darn accurate!

I'm very impressed. :)

[ballaratdragons]

WOW!!!!

3 hours and Canopus is STILL in the centre of the FOV! I find this quite remarkable!!!!!

Is this a common thing with these add-on duel drive motors?
I really didn't expect it to be THIS accurate!

[ballaratdragons]

Just coming up on 3.5 hours and we are now clouded out :sadeyes:

Would have been nice to see just how long Canopus would've stayed dead centre!
But that is one of the problems of Astronomy, we can't control the weather.

But I must admit, it was an excellent result :thumbsup:

[Geoff45]

Yeah, the overall tracking is quite good on mine too, but there is rather too much PE for unguided shots longer than about 30s with 1200mm focal length on mine.
Geoff

[mrsnipey]

Can I ask a noob question Geoff, what does PE stand for?

[erick]

mrsnipey, look up "periodic error" (and it doesn't seem to be in the IIS glossary) - it's all the fault of the "worm" again! :D

Read up here, for example:-

http://www.pk3.org/Astro/index.htm?astrophoto_mount_errors.h tm

[lineout]

Hey balaratdragons,

Can you give us an idea on portability and ease of set up. I'm thinking of dumping my LX-90 forks for an eq mount.

Cheers.

[ballaratdragons]

An update from last nights tracking trial.

I went back outside at 2am, the cloud had thinned to fine fog. I hair-dryered the lens and EP, and Canopus was STILL in the centre!!!!!!!

That's 4.5 hours! :eyepop:





EQ5, HEQ5, and (if you have a little bit of muscle) an EQ6 are easy enough to carry around. They aren't overly heavy. The trick on set up is getting the knack of Polar Aligning which is covered in many many threads in here. After a few goes, it gets easier like most things.

The EQ5 is a bare minimum for the 120mm refractor, but would be much more stable on the HEQ5 or the EQ6.

If you only had a light, short tube scope, the EQ5 will be fine. And (as I read in another thread in here) can be set up to Autoguide :thumbsup:

Depending on your scope, I'd suggest HEQ5 as a minimum for Astrophotography.

[mrsnipey]

Thanks Erick.

[Geoff45]

Periodic Error. Because of small inaccuracies in gears that are on average accurate, a star centered in the eyepice will slowly drift back and forth in the eyepiece. Anything fro a few arc seconds to an arc minute or more, depending on the quality (and usually price) of the mount.
Geoff

[mrsnipey]

Thanks Geoff.

[joshman]

hey ballaratdragons, what brand of mount was that with? i'm looking at getting teh skywatcher german HEQ5 mount in the very very near future, and what all this business with the dual drive motor add-ons?

[ballaratdragons]

Hi Josh,

The EQ5 I did the test on is a Skywatcher, same brand as the HEQ5 & EQ6.

Dual drives are available from a lot of the Astro shops in Oz for EQ1, EQ2, EQ3 and EQ5, but I've never seen them as an accessory for HEQ5's.

Andrews, Bintel, and MyAstroShop do sell the HEQ5 with them pre-fitted, making it a cheap mount.

Andrews - $950 http://andrewscom.com.au/site-content-section-10-skywatcher.htm#accessories

Bintel - $999 https://www.bintelshop.com.au/Product.aspx?ID=7347

MyAstroShop - $1055 http://myastroshop.com.au/products/details.asp?id=MAS-042

Might be a better way to go, rather than trying to adapt something.

Regards
Ken

[joshman]

awesome!!! i just put in my order for a HEQ5 mount, hopefully i'll be able to pick it up on friday, that coupled with my soon purchase of an ED80, and i'm fast on my way to doing some real astro photography!

[ballaratdragons]

Onya Josh!

Did you order one of the above that I linked you too? with the drives built in?