Johnsonian EQ Platforms

[iceman]

Was enquiring about prices of the Johnsonian EQ platforms, and got this bulk mailout:



Does anyone have experience in these?

US$399 + shipping (for my 10") isn't cheap, but it's not a bad price, and would give me that much sought after tracking.

What are your thoughts?

[slice of heaven]

Will you be satisfied with just the single drive Mike?
Can it be upgraded to dual drive?
I'm not up to speed totally on the tracking capabilities of single or dual drives but I've seen much better pics from dual axis drives on platforms.


Slice

[[1ponders]]

If your platform is properly polar aligned then you shouldn't need a Dec motor. Mike do you have a link for the Platform (I'm being lazy and not googling :) ) I'd like to check out how they are operated

[rmcpb]

That's a whole lot of dollars for the dual axis but if photography is your game then it may be the way to go (so long as you have the readies for it).

On a more realistic note the single axis platform would allow you to do longer exposure sets with the individual images more aligned than what you are getting with the static mount. This should allow for better stacking in Registax and better final images I would think. Its still an expensive piece of wood and wheels though.

Cheers

[ving]

go for it mike!
and buy one for me!! ;)

[seeker372011]

Mike:

before you buy a platform I suppose you have checked how the economics compare with buying an EQ5 with dual drives in Oz?

You can use your OTA and possibly setting circles with the mount...

shipping a platform from the US would be horrendously expensive, plus customs will likely slug you a processing fee and GST

[ving]

wouldnt a scope the size of mikes require a eq6? its a big scope! :)

[Starkler]

As I recall there were two major vendors of eq platforms in the usa. One had a good reputation (Tom O.) and the other lousy with all sorts of problems, underrated motors etc. I think that was the Johnsonian so do your research before laying out the $

[iceman]

Paul, http://www.johnsonian.com/

Slice, single drive would do me. I don't have a problem with having to polar align it if it means saving US$500 :)

I'm not expecting/wanting to be able to long-exposure deep-space photography, I want tracking for:
a) visual use, for myself and for family and friends so I don't have to realign between each person
b) planetary/lunar webcam work. So I don't get the motion blur and should enable me to use more magnification (3x or 4x barlow) to get a bigger image scale.

Seeker, I investigated an EQ6 (EQ5 wouldn't be strong enough), and the EQ6 would cost at least $1400. Plus the EQ6 is heavy to lug around and I prefer the simplicity of a dob at this stage.

Starkler, thanks for the heads-up, I intend to do more research before outlaying any $$$.

[[1ponders]]

Looks nice Mike. I'd be interested in how accurate you can get your latitude adjustment. The manual says 2 degree increments, Might be good enough for visual but photography? Hmmm:confuse3:

However I checked out some of the images for the other platform posted here http://www.astronomy-mall.com/regular/products/eq_platforms/images.html and they look very spectacular. I look forward to seeing what you can do with it. :) assuming you get one of course. :) Certainly looks great for planetary and luna imaging.

[janoskiss]

I imagine that for visual tracking motorising the motion (with independent speed control on alt & az) would be adequate and cheaper. That's what I plan to do with my dob.

The main problem I see with the EQ platforms is that they are latitude specific, so you can't take them too far nor resell them to fellow dobbers much further North or South of your location.

[slice of heaven]

For visual and planetry Mike the eq platforms are great on single drive. If you check those images on the link above ,over 90% would be dual axis drives.Bit of an advertising ploy for the unwary.
Going by your images in push/pull mode you'll be posting some great ones on an eq platform. AND there'll be dso's thrown in.
I looked into these about 2 years ago and for a big dob it is the cheapest form of tracking. At the time I couldn't justify it for just myself.

Janos : Most commercial eq platforms aren't latitude specific, most can be adjusted to suit your location.

Slice

[[1ponders]]

By the look of these new ones Steve they have an adjustable latitude scale from 25 degree to 55 degree. If that's the case then they wouldn't be much use to anyone north of about Marybourough north of the Sunshine coast and Carnarvon in Western Australia

[seeker372011]

is it true that film..being so much slower-is more forgiving of tracking erors than CCD chip?


the CCD images on the site are 15 or 30 second images, the film images are 45 and 60 minutes!

[[1ponders]]

IMHO I think you'll find seeker that using the 15 - 30 sec images your alignment doesn't need to be as accurate, plus there is no need to take dark frames.

I've tried to do film imaging when I first began experimenting with astrophotography but gave up as I couldn't get my alignment accurate enough with the scope I was using. I was still getting star trailing from tracking errors. After a few minutes the trails were not as bright due to reciprocity failure but they were still there. Damn frustrating too.