What's your scope? - Page 3

iceman (Mike) · #41 01-09-2005, 07:40 PM

Quote:

2. With the folded design we have greater focal lengths. 2500mm with a 2.5 powermate produces large image scale. This means our images of planets are bigger than any other scope. An SCT wins hands down here.

Generally, that's true. It's much easier to get a larger image scale than an equivalent aperture newt. However the focal length is still ultimately dependant on the seeing. I've seen planetary/lunar images at approximately 10,000mm - with a large newt (like Wes Higgins 18" starmaster, or even Orion (Ed's) 18") it's still possible to achieve that focal length with a 5x powermate. But it really needs a night of perfect seeing to get any sharp and useful at that focal length.

So yes, for a 10" aperture if I wanted to do planetary imaging I'd probably get an SCT, but there are also drawbacks for widefield imaging, because of that exact reason - focal length. You just can't get a wide field, which is why you SCT guys get 80mm widefield scopes

Also for purely visual, there's nothing like a widefield view of the milky way through a newt.. I just don't get the same feel through an SCT because it's double the focal length.

Anywya each to their own, as long as the person looking for a scope to buy understands the pros and cons of each, they can make up their own mind.

beren · #42 01-09-2005, 07:59 PM

Mike when i sold my newt and got a SCT i was worried about the widefeild viewing angle but in conjuction with a focal reducer i find it pretty satisfing , i thought i would be using my longer focal length pieces a lot more but for the main my 22mm nag works a treat .For imaging though i admit i prefer the little 80mm .

acropolite (Phil) · #43 01-09-2005, 09:46 PM

let's not forget the continual attempts by the dobbers to motorise their canons and turn them into go-to's...

slice of heaven · #44 01-09-2005, 09:52 PM

Quote:

Originally Posted by acropolite

let's not forget the continual attempts by the dobbers to motorise their canons and turn them into go-to's...

Only because we've still 3 to 4 thousand $$$$ left in our pockets to play with

beren · #45 01-09-2005, 10:06 PM

there wouldnt be to much $$$$ left in comparision when you fit a argo navis and a servocat

slice of heaven · #46 01-09-2005, 10:11 PM

Quote:

Originally Posted by beren

there wouldnt be to much $$$$ left in comparision when you fit a argo navis and a servocat

Wouldn't that be nice.

rumples riot · #47 01-09-2005, 11:43 PM

Boy Dob owners!!! Funny little dudes. Good for some fishing, finding the bait is real easy. Before you know it they are peeling off line.

You'll notice us SCT owners have not been doing the attacking

Starkler (Geoff) · #48 01-09-2005, 11:51 PM

Quote:

Originally Posted by rumples riot

Boy Dob owners!!! Funny little dudes. Good for some fishing, finding the bait is real easy. Before you know it they are peeling off line.

You'll notice us SCT owners have not been doing the attacking

I dont see anybody attacking anybody, even though some get overly defensive when the weaknesses of SCT's get mentioned

I Guess thats understandable after having spent a truckload of $ for their stubby tubed scopes.

Quote:

let's not forget the continual attempts by the dobbers to motorise their canons and turn them into go-to's...

Nope, I'd rather push my dob than ride a goto

iceman (Mike) · #49 01-09-2005, 11:59 PM

Who's attacking?

The dob vs SCT debate is always going to be around, nothing will ever change that

rumples riot · #50 02-09-2005, 12:01 AM

Yeah but we didn't start it. We could mention the short comings of Dobs. That would be real easy. Especially those short F ratio versions. Why is it always the Dob owners trying to find a reason to justify why they bought a dob?

Jealous they is, only Jealous.

iceman (Mike) · #51 02-09-2005, 12:06 AM

There's nothing wrong with short F ratio's, that's what gives the wide field that is a "pro" for dobs. Just as the long F ratio (or, focal length) is what you gave as a "pro" for your SCT (from a planetary imaging viewpoint).

Of course the low F ratio means collimation needs to be spot on and eyepieces can be challenged to give sharp views across the field, but that's what you accept when you buy a dob. Just as you accept a narrow field of view and a more expensive scope (plus setup time etc) when you buy an SCT.

There's always arguments for both scopes, and those shortcomings whatever people claim them to be, are part and parcel of owning them.

cometcatcher (Kevin) · #52 02-09-2005, 12:32 AM

I made a couple of f8.8 dobs. Beautiful planetary scopes. Unfortunately I sold them, and don't I regret it.

The fast ones I have now are nice for star fields but suck for planets.

Sorry but I can't vote. I have no primary scope. I love all my scopes equally. That's like asking which is your favourite child?

asimov (John) · #53 02-09-2005, 12:44 AM

Well, I'll stick to my refractors for planets & fast big aperture newts for those wide & bright views..For the time being at least.

slice of heaven · #54 02-09-2005, 10:09 AM

Everybody gets defensive when their type of scope is attacked.

There is no ONE perfect scope.
Every type has a place and benefits, over another style. What makes it more suitable for an individual is strictly up to the individual. If your happy with your scope and you use it, thats all that matters.
Take Striker (sorry Tony,NO disrespect here) for instance,started with a dob but found it not suitable. Went for the Meade Sct on fork mount, then changed to an Sct on an eq mount.He seems pretty happy with his setup now.(I would be too)
Me, I like my dob. Quick setup,no electrics,simple to operate and good views.
Yeah ,goto would be nice, but for me not a neccessity on the dob.

Still, reflectors are way better than refractors

cometcatcher (Kevin) · #55 02-09-2005, 12:55 PM

Quote:

Originally Posted by slice of heaven

Still, reflectors are way better than refractors

Nice use of bait.

My best views of comets have been through short fat refractors.

I'm with whoever it was that said that we need one of each. A wide range of magnification needed for certain objects - wide for star fields and comets to narrow for planets.

Photographers have different requirements to visual observers also. A doublet refractor may be fine for visual use, but it sure blows halos in pictures. Obviously the photographers need tracking, the visual user doesn't.

Because of this I suspect the amateur astronomer with the widest range of interest will also carry the lightest wallet.

elusiver · #56 02-09-2005, 01:13 PM

OMG!!! what's going on in this thread?!?!

it was never meant to be a my scope is better than yours thread!! more a sort of pie chart of what iis members primarily use!

el

p.s. the dobs are the best. not because i have any scientific fact to back this up.. but simply cause I have one.. so it must be the best.

cometcatcher (Kevin) · #57 02-09-2005, 01:24 PM

Going by the poll results you have your pie chart.

Looks like dobs are the favourite, followed by SCT's, then EQ Newts and lastly refractors. Poor refractors.

OK, I suppose I better vote. It's a hard one cos I use them all but I guess EQ Newtonian would be what I use a lot of, mostly because I like to photograph star fields and comets, and I'm cheap.

elusiver · #58 02-09-2005, 01:39 PM

i'm still not satisfied with the number of votes though. 71 out of 400 odd members. would've liked a fair few mote voters.

el

asimov (John) · #59 02-09-2005, 05:46 PM

Quote:

Originally Posted by slice of heaven

Still, reflectors are way better than refractors

..

slice of heaven · #60 02-09-2005, 10:31 PM

Sorry John , just teasing.
Without refractors, what would we use for finderscopes?