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View Full Version here: : Upgrade Choice: Scope + EQ5 or a HQE5?


Atlantia
03-06-2010, 03:11 PM
Andrews Communications is having a sale on their Skywatcher telescopes, and I'm looking to upgrade my 5 inch Newt...
Currently, I'm deciding between purchasing the 8 inch Black Diamond on the EQ5, or just the HQE5 mount; unfortunatley the HQE5 AND the scope aren't an option. I'm looking for guidance as to which one to go for, opinions?
Is it likely that the 8 inch BD will be too heavy for the EQ5? Also, I should add that this will be my second telescope.

Thanks, Kate

:)

ausastronomer
03-06-2010, 03:36 PM
Hi Kate,

Are your intended uses visual astronomy, astrophotography or a combination of both?

Cheers,
John B

Atlantia
03-06-2010, 03:39 PM
Hi John,
I dont foresee me owning a ccd or dslr in the near future, but perhaps in a couple of years. Therefore it will be for visual use.
Thanks.

dugnsuz
03-06-2010, 04:10 PM
The EQ5 mount will handle the 8" Newt for visual work very well.
The system would probably not be ideal for astrophotography though.
That said, the EQ5 Pro mount is a perfectly good GoTo mount to introduce one into astro-imaging...great for widefield DSLR and small scope work (ED80 for example).
It even has an autoguiding port!

Doug:thumbsup:

M_Lewis
03-06-2010, 09:29 PM
I don't believe an EQ5 or an EQ5-goto will adequately support an 8" scope. As the upper limit of the EQ5 mount is ~8kg. Running the mount at it's upper limit will result in stars that love to jump around in the field of view.

The HEQ5 PRO (goto version) is rated ~17kg and will easily take an 8" scope. You are not running the mount to its upper weight capacity. If you can take the HEQ5 Pro option it's worth the investment as it won't limit you scope choices down the track, nor will it be as prone to wind shear vs the standard EQ5 option.

dugnsuz
03-06-2010, 09:58 PM
Fair enough - didn't check the BD-200 weight (8.75kg) before posting...just went on anecdotal/personal experience.
Sorry Kate
All the best with your choice
Doug

bmitchell82
03-06-2010, 10:33 PM
To be honest, if your not worrying about photography, then a eq5 will be just fine, your not looking for a ultra stable mount, your looking for tracking abilities. Because of the eyes ability to track movement, it doesn't matter if the scope wobbles a little bit. If you don't believe me mark on this just look at shane, he runs a 12" dobsonian + all the other bits on a EQ6 which is far over rated for the mount at close to 34kgs (eq6pro rated somewhere about 24kg), yet it still tracks well.

That said if you have the ability to go for a bigger mount then do it, but if your budget restricts then just go for the 8"+EQ5.

M_Lewis
04-06-2010, 07:07 AM
A sparrow would fart 2 miles away sitting on top of a mountain, and the wind shear it creates would wobble the scope. Having previously owned an eq5 I don't see how the eq5 would be deemed suitable under any wind shear, mild or higher. Hence why I now own an neq6 pro.

I am quite aware of people who run 12" on an eq6, and get away with it, however they always are quick to add it has to be on a very still night for astrophotography otherwise it's practically useless, because they are up at those upper weight limits and present a very large surface area for wind shear.

Obviously one's budget is the overall limiting factor, but limiting one choice to a lower mount is the worst thing anyone could do.

The foundation of good astronomy starts with a good telescope mount.

chris lewis
04-06-2010, 07:15 AM
GSO sell there 8in. and F/4 and F/5 on a Skyview / EQ3. Really this is at the max. for those mounts - but to be really honest they are undermounted esp. the F/5. I used a 8in. F/4 on the Skyview / EQ3 mount for 2 years for visual and it 'worked' but was at the limit.
An EQ5 would be OK for both F/4 and F/5 visually.
I have used a GSO 8in. F/5 on my HEQ5 and that works very well esp. for visual. One club member has a GSO 10in. F/5 on their HEQ5 for visual only. That is at the max. for that mount - it 'works' but dampening takes 7-10 seconds.
I have my ED120 Equinox with a finder and binoviewer plus a WO 66ED with 2in. accessories on both OTA's on my HEQ5 - which is slightly more weight then a 8in. F/5 but and it tracks very well.
Balance of course is important and strong air currents will also ruin your night.

Chris

ausastronomer
04-06-2010, 08:31 AM
That is the best advice given so far in this thread and the primary reason a very large number of people choose dobsonian mounts for visual astronomy. STABILITY.

You can get them without any form of electronics. You can get them with push to DSC's or you can get them with full GOTO and tracking capabilities. Importantly with a small dob the eyepiece is usually always in a convenient position. With an 8" or larger equatorially mounted newtonian you quite often need to be a contortionist to get to the eyepiece. Conversely, quite often with an equatorially mounted refractor you spend 1/2 the night rolling around in the long grass with the black snakes.

If you have your heart set on a newtonian scope for visual use I would seriously consider going to some form of dob mount, with or without DSC's and tracking.

Another alternative if you must have a GOTO mount, is to go with an 8" SCT on a GOTO mount. Being a lot shorter in length it has a much smaller moment arm and doesn't need quite as strong a mount as an equivalent aperture newtonian for the same level of stability. That having been said, IMO an 8" SCT is not quite as good a scope optically as an 8" newtonian, for a plethora of reasons. It is however easier to mount and a lot more storable, portable and transportable. In addition, with a SCT Equatorially mounted, you don't end up with your head all over the place like you do with a newt on an EQ mount. A SCT would also be well suited to imaging, if you decided to head down that path in the future.

Cheers,
John B

bmitchell82
04-06-2010, 11:52 AM
You are dead right when one is thinking about astrophotography, but due to the phisology of the human eye it is made to track objects. if a sparrow farted 20km away it dosen't matter as it does not affect the human eye. different story all together for one who is trying to focus 1 start on 1 pixel for 20 minutes.!

Kate is obviously looking for Tracking abilities or she would most likely have gone the Dob route already. I still stand by my opinion that for Visual only a EQ5 will work sufficiently!

well i guess i don't know what im talking about so ill just bow out.

Hope goes well kate

Brendan

Atlantia
05-06-2010, 06:40 AM
Alright, thankyou everyone that has given advice. I ve decided on the HQE5 mount, but have also -very fortunately- found a deal in which I can also get the BD 200. So hopefully this will give me the best of both worlds : a sturdy mount and aperture.
Thankyou all, I value your input!

dugnsuz
05-06-2010, 08:45 AM
Nice one - a "win win"
Have fun
Doug:thumbsup: