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jjjnettie
04-06-2009, 04:56 PM
Would anyone be able to tell me the approx. weights of these OTA's.
GSO 6" f8
GSO 8" f6
Thanks :thumbsup:

Paul Haese
04-06-2009, 05:29 PM
JJJ are you referring to the RC versions? If so I think the 8" is 6 kg.

jjjnettie
04-06-2009, 05:33 PM
Don't I wish.
I'm looking at the newts Paul.

Paul Haese
04-06-2009, 06:21 PM
Sorry, I thought you meant the RC version.

lacad01
04-06-2009, 06:23 PM
8" is about 9.5 to 10kg, not sure about the 6"

pmrid
06-06-2009, 04:35 AM
Jeanette, does this mean you are 'moving up'? If you want to have a play with an 8" GSO Newt, you're welcome to have a look at mine. I've mounted it on an EQ6 Pro. It's early days but if the clouds mand the moon will just give over for a little ... Give me a ring.
I'll check out that Fringe Killer of yours on my refractor while you play with the Newt.
Peter

jjjnettie
06-06-2009, 08:08 AM
Sounds like a good idea Peter.
I'm looking at something with a bit of focal length for planetary work and maybe some dso stuff.
The scopes has to be light weight cause I'm getting a bit feeble with my health.
Other alternatives for me are;
Andrews has their 90mm F10 refractors on sale, but its achro
or
buy a good barlow or powermate to use on the ed80.
??????????????????????????????????? ??????????????????
decisions decisions

AlexN
06-06-2009, 09:47 AM
JJJ - For planetary work, Aperture is king.. Focal length alone won't cut it.. your ED80 with a 5x powermate will not produce highly detailed images. The 8" F/6 newt with a 5x powermate on the other hand should provide you quite nice images... I know mine used to or me.. You need to remember, 80mm is not catching much light to start with, when you then extend the focal ratio to F/37 with a 5x powermate, you will be choking the camera for light.. a 6 or 8 inch newtonian will surely serve you well for planetary work, and a little more aperture can never hurt when chasing DSO's either! Call bintel/andrews and ask them about the weight of the Newts, Im sure Luke will be able to weigh one of the OTAs for you...

pmrid
06-06-2009, 01:06 PM
Have you priced the Powermate vs a Barlow. I checked Peter's in Hong Kong and his 5x Powermate is HK1490 (A$242) vs a 3x Barlow at HK$940 (A$152). For the relatively small difference, a Barlow would be a poor choice, IMHO.
Peter

TrevorW
06-06-2009, 02:43 PM
GSO 6" not to heavy
GSO 8" a little bit heavier however should be fine for those not yet over 55 who suffer from serious back problems

Personally suggest 80 to 110 ED f/7 refractor as I know you like imaging

Cheers

jjjnettie
06-06-2009, 03:40 PM
I'll just have to win that 6"RC at Astrofest won't I.

AlexN
06-06-2009, 03:59 PM
If you're numbers come up as often as they did last year you're in with a chance JJJ !! :) Best of luck!

Tandum
06-06-2009, 06:01 PM
Jeanette,
A vixen vc200L is the other option. About 5kgs with a handle on top. Don't need coma correctors etc etc etc, just a camera adapter and a focal reducer if needed. An eq5 will carry it and a guide scope no problem. One went here the other week for $1K or about $1.9K new delivered. Forget those GSO RC scopes, you need to hang a brick off the front of them to get balance and a half meter of extension tubes out the back to get focus :D

RobF
06-06-2009, 06:19 PM
I found it a bit hard to find this too JJJ when I was researching. These sites are effectively the same OTA you're describing for the newts I think:

http://www.skywatchertelescope.net/swtinc/product.php?id=64&class1=1&class2=104

http://www.skywatchertelescope.net/swtinc/product.php?id=63&class1=1&class2=104

That is, about 5Kg for the 6" and 8.75kg for the 8"

Robin is probably right about considering the VC200Ls 2nd hand - I think I've read the larger central obstruction is better suited for CCD nebula work rather than long FL planetary though. I won't say more - you know I'm going to be biased! :lol:

AlexN
06-06-2009, 06:29 PM
The VC200L is nearly twice the cost of an 8" newtonian... And although they are purpose built imaging scopes, for planetary imaging/viewing, the larger central obstruction is really going to be a killer in terms of planetary contrast.. The larger secondary is great for fully illuminating a 35mm format CCD, however it is also the deal breaker when it comes to visual observation and planetary work... The same can be said for the GSO RC's.. As for the Newts, at 8.75kgs, the 8" shouldn't be too much to handle...

Tandum
06-06-2009, 07:24 PM
I'll dispute this .. add these items to the dob: rings and a dovetail, add coma corrector, add quality lowprofile focuser and maybe the need to move the primary mirror to achieve camera focus plus an extension to achieve eyepiece focus. These sort of evens it out.

AlexN
06-06-2009, 07:35 PM
Unless you were to buy something like the Skywatcher black diamond 8" F/6 Newtonian OTA for $599 that comes with rings and a dovetail, and is set up for imaging (As I understand a DSLR will come to focus in them out of the box) The coma corrector is only really nessacary if you do plan on imaging with the DSLR... If it was being used with a small sensor like the GSTAR or a planetary imaging camera, the MPCC would not be needed...

I'm not saying either scope is not a good choice. It just depends on the desired application. For planetary work, the VC200L isn't the better option. for a dedicated deep sky imaging scope, the VC200L would be better...

Tandum
06-06-2009, 07:43 PM
I've never heard of this before.

pmrid
06-06-2009, 11:48 PM
It's true. My GSO 8" is the same. I use a short adapter for eyepieces but the DSLR comes to an easy focus without one. The MPCC is also handy because it eliminates the need for an extra T-Ring tube thingy and is also threaded for a Moon and Skyglow filter if needed. It doesn't alter the F/ ratio or alter the focal plane. Here is a simple shot of Acrux taken last night (in 90% moonlight).
Peter

Tandum
07-06-2009, 12:02 AM
There ya go. I'm guessing it will focus with a coma corrector?

pmrid
08-06-2009, 04:07 AM
I use a MultiPurpose Coma Corrector (MPCC). The quick shot I attached to the previous post was taken with it in place so, yes, it can be brought to focus without having to start hacking away at the OTA.
Peter

Hagar
08-06-2009, 08:21 AM
I have to comment here Alex. Some weeks ago I spent a night out doing some visual observation with my little VC200L. I cannot comment on the planetary skills of this scope as there was no planets observed on the night but as for general observations it is the best scope I have owned and looked through. Galaxies could be easily distinguished, Nebulas were big and bright and at the time the comet up there was brilliant. A few there on the night were quite taken by how well this little scope performed. I have had a few 8" scopes and find this is by far the best I have owned. (8" Newtonian, 8" Celestron SCT, 8" Dob) Both the dob and the Newtonian had to be modified to come to focus with DSLR attached.
As I have said I can't comment on planetary work (not my bag) but for general viewing and photography it is a real winner. A little tricky to collimate should it need it but all in all a great scope.

There seems to be a lot of people on this forum very keen to give roving reviews of scopes they have not used. It is a shame that this is the case as it does make it hard to decifer the truth from the rubish when you are after some real advice. Come on people, stick to what you know, what you have direct experience with and not the ramblings of forum users who have nothing better to do than pass ill founded comments. I would have thought the RC thread would have proved this.

AlexN
08-06-2009, 09:46 AM
Fair call Doug.. I was assuming based my experience with reflectors and central obstructions... my 8" newt provided higher contrast views than my 8" RC, im going to put it down to the slower F ratio and the large obstruction, hence why I figured with the VC200L being a slower ratio than the RC and having a similarly large central obstruction, would provide a lower contrast view. The C11 wasn't too bad (I think aperture bridged the gap) but its central obstruction I believe was 39%.. not closer to 49% like the RC, or 45% ish that the VC200L has...

I was in no way saying the VC200L is a bad scope, I think I mentioned that.. Just saying that, from my experience with different reflectors, a large central obstruction usually hinders a scopes visual performance..

I was actually seconds away from buying one when I bought my RC... I like the VC200L a lot..