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View Full Version here: : Bintel 200mm reflector and Andrews 200mm reflector


xelasnave
26-07-2017, 06:13 PM
Since getting excited about getting going again my head is spinning all day ...researching this and that it just like when I started out and I.am just soaking it up.

I would love to go 10 or 12 inch but given I am not as fit as I once was, ...its only my legs cause I am still not aging, ...well my legs relate to my back and I don't know, I just worry the scar will open if I push things..so eight inch seems sensible...


So F4 or F5?

I.like longer focal length because I think they are more forgiving but that comes from thinking of making my own mirrors..I expect f4 is best and optics are good.

Bintel and Andrews each have eight inch reflectors and I own each business cause each owner personally delivered me goods ... I don't.forget special treatment.
There are ties to each.

I expect one scope is as good as the other but can anyone tell me different...you know one is better because...
F/L and where to buy.

Maybe I could got ten inch but the question as to who to go with will remain.

Any thoughts?

Any help will be really appreciated I just cant stop thinking about this stuff ..when I switch on it becomes obsessive ...I have a list of decisions and I have to settle what I am doing so I can do others things.
Alex

raymo
26-07-2017, 06:32 PM
The first and most important thing to ascertain is that whichever scope
you choose has enough back focus to allow the fitting of a camera.
. All Skywatcher ones do, but many other brands or models don't.
F/5 is certainly more forgiving, but 8 or 10" is plenty of aperture, so
the fastest available scope is not an overarching consideration IMHO.
raymo

xelasnave
26-07-2017, 06:42 PM
Thanks Raymo I will follow up on that very important observation.
And you think go ten inch... I will look closely at the weight difference.
Thanks for your reply.
Its been perfect here all week after the wind dropped...I don't know what its like upstairs but it sure is great just with binos.
Alex

raymo
26-07-2017, 07:30 PM
I personally would go with 8" [around 9-10kg]. A 10 comes in around
14.5kg + any fittings such as an electric focuser, Telrad, etc.
A mount of HEQ5 size will easily handle an 8", but most people who
use 10" scopes move up to NEQ6 size. I suppose in the end it all
comes down to whether it will remain in place, or will be demounted and
moved inside after each session, and finally, how fit and strong you are.
raymo

cometcatcher
26-07-2017, 07:49 PM
I found the GSO steel version 10" F4 pretty heavy and awkward to lug around. The 8" is much easier on the back. But if it's going in an observatory then it doesn't matter. You only lift it once.

Wavytone
26-07-2017, 08:20 PM
Alex,

1. I would steer clear of f/4. It means it will do low power nicely but as for high power... fuggedit. Many eyepieces do not handle f/4 well, unless you plan on a box of Naglers and Pans.

f5 is closer to the optimum (which imho is f/7).

2. While I appreciate the desire for aperture, an 8" will be easily manageable for you for many years. A 10" will be a heavy lift and enough to put you off. Think about the future - we're not young anymore.

I'm also old enough (60) to appreciate this ... my 7" Skywatcher mak is easy peasy, but the 9" Santel mak is twice the weight and a real concern. While I lift it now easily enough, in 10 years time probably not. This is one reason I'm having second thoughts about selling the 7".

Another IIS member I know keeps an 8" SCT for the same reason - its not his dream scope, but it's the one he uses most because it's convenient.

IMHO it's much like cameras - once I had a big heavy DSLR thinking it was the ducks nuts, but in reality I shot 19X as many photos with my little compact that went everywhere, always.

glend
26-07-2017, 08:30 PM
If you look at their respective websites you will see they are near identical, both actually made by GSO. All Bintel branded newts are made by GSO. Andrews versions
are setup for imaging so they will easily handle and allow focus with any camera DSLR or other. It becomes a choice of f4 or f5. I have owned a GSO 8"f5 and its not very heavy at all. Sure f4s might be a little lighter but i think f5 offers a more flexible scope with a focal length of 1000mm verse 800mm in the f4. The 1000mm focal length is still wide enough to be useful on nebulas, but allows you to get in closer on targets like the Grus Quartet. Andrews is usually a little cheaper than Bintel on these GSO scopes but with Andrews your getting an unopened box right out of the bonded warehouse. You might want to check with Bintel about what they do with theirs, ie do they open the box and check the collimation, etc. Bintel pride themselves on full service, which may justify the price premium, but i have never had a bad GSO from Andrews. Mirrors are great in both. If you buy an imaging newt i suggest you buy a 35mm 2" extension tube to put in the focuser so you can reach focus with any eye piece if you use it visually.

xelasnave
26-07-2017, 09:10 PM
Thank you all very much.

The 8 inch f5 sounds the best choice.

I have an old eq6 and although it may handle a10 inch I like not to run a mount near the advertised carry weight.


I will go for a guide scope 80mm x 400 which I have its not flash but I expect it will work.
So that is.extra weight.

I will ask Bintel what they can do for me ..it would be great to have it checked before I take it home...plus I will never forget when I told Mrs Smith I was taking the 12 inch home on the train her insistence that she drive both of us home..that was decent.
And maybe when I pick it up I van call by the fish market and get a lobster as a little treat and celebration. May get a new eq6 soon after so I can give that sale to Andrews.

And I have had another idea seeing we can get 3d printing but I will open a new thread...

Thank you all I really appreciate your help.

I have no problem advising other folk but when it comes to advising myself I feel I don't listen to my advice ..then we argue.

Thanks heaps.
Alex