8", 10" or 12" dob as a starter scope?

[darkskybondi]

So what do you reckon? Looking, for the moment, at the Skywatchers: Clearly the 8" is more portable; the 12" is, by all accounts, a water heater; and the 10" seems a reasonable compromise. Now I want to stay under $1000 (putting the collapsible 12" out of range) and so I can't help thinking that I should just get the largest aperture I can for the money and go with the 12". The question really is: will taking it out to the patio become a massive chore? Much less, taking it out to the country...

Your opinions? :)

- darkskybondi :newbie:

[Ian Robinson]

Easier and cheaper to upgrade the 8" or 10" to an equatorial later, don't need as big a GEM as you'll need for the 12".

My 10" f4.66 newtonian is a handful , but still portable and I can slide it across the back seat in the pajero if I need to.

If there is a need to lump the scope around or transport it in the car to somewhere else , the 8" or 10" are the go .

If you'll not need to move it very far to observe through it, or can handle the extra mass (single handed) go for the 12" keeping in mind that you'll likely want to convert the scope sometime and put it on GEM to do some imaging = and a bigger more expensive GEM will be required to adequately handle the bigger scope.

Another question to consider is who else is likely to be looking through it on a regular basis, eyepiece height at zenith may be an issue.

I read somewhere that retired priest who's discovered stacks of supernova with his 16" dob sets it up on his patio to do his sweep.

[iceman]

If you're at all worried about portability, get the 10". It is quite a bit smaller, lighter and easier to move/transport.

It still has enough aperture. I absolutely loved my 10" dob. I had some brilliant views through it and it got me hooked in this hobby.

[Bobj]

After some excellent advice from the crew here, I purchased a 10" dob. Never looked back, since. It is quite portable ( I have to be careful with loads...liver problems) and, if you purchase a cheap Bunnings trolley, you can manoeuvre it quite easily around the garden. I have a 2'x2' section of 9 ply that I put on the lawn, and simply put the dob on it for an evening's viewing and no problems with dew, or stability.

[Dog Star]

Went through the same angst myself some time ago.:)
If you have a vehicle that will take a 12", then that's the one to buy.
Nothing wrong with an 8" or 10" but if that's the way you go, you'll always be wondering if you should have gone bigger.
It's ALL about aperture. Don't stuff around, get the 12".
I did.

[kinetic]

I totally agree with you Phil....I've got a 12 and it's giving me
gobsmacking views.
Portability is the issue. It's not....its definately a 2-man scope to lift
it anywhere in the yard, car etc.
He'd hate us if we sold him on the 12 and didn't have a companion
everywhere he went to set it up.

That's why you plonk em on a GEM and they stay there :D

Maybe the collapsible 12 is an option?


Steve

[koputai]

I have both 8" and 12" Dobs. The 12 is by far the awesomer (new word!) scope to look through, and it impresses the trousers off household visitors.
For actual user friendliness though, the 8 is the winner by quite a margin. Carrying the 8 into the yard for viewing is very easy, whereas getting the 12 out is quite a chore. The Bunnings trolley has been bought, but it'll need some modification before it can carry the GSO 12" safely.
A well tuned 8" gives fantastic views, especially when combined with a premium eyepiece.
That said, apperture rules, so my 12" is about to undergo some heavy weight loss therapy!

Cheers,
Jason.

[bmitchell82]

hehehe, for christmas you could buy your scope a pressy.... a Jenny Craige voucher :D hahaha.

With that being said, the 12" no doubtedly is far more awsomer than the 10" but like you said, its kinda a 2 man affair unless you got trollys and the like, but if you want to stick it onto a mount later, your looking the 5k variety or something of the sort instead of being able to slap it onto a eq6.

Its all about your vision of what you want to do, if your eyes are (no disrespect) crapola, then astro photography is going to give you a view so much better than even the best eye piece can give you. why because you can put it up on your 50" LCD and look at it! that way your eyes wont suffer the static and short sightedness you have stated previously. Also you can get video cameras specifically for astronomy (can somebody name them i have forgotten), so you can have the same experience, just have it on a screen for you to look at!

And the last piece of golden advice that i was given was. The best scope is the scope that your going to use the most.! weather it be 80mm, 10" or 20"...

[NewToStars]

like others have said. if portability isn't an issue go the 12". as far as 8 and 10" versions are concerned go the 10".

on a dark sky night i had my 8" and another member had a 12". the difference in imaging is so much better with the larger scope.

[darkskybondi]

Hehe well thanks for the replies, guys. Now I'm a little confused. I have seen the 10" and I certainly think I could lug it around quite easily in two parts. Is the 12" that much heftier? I know the tube itself goes from 14kg in the 10 to 22kg in the 12, but my guess is that that is still manageable. Given, as Brendan quite rightly pointed out, my poor vision, I probably won't get as much out of a 10" as you fellas would. But if I don't end up using it as much because it's so fat... clearly a dilemma.

It's all about compromise, hey? Anyway I'll let you know what I decide when I decide. Hoping for clear skies this week to get to a nearby club's viewing session.

Cheers again and merry xmas,
DSB

[bmitchell82]

all i say is that a 12" will not be any good for photography well other than planets on a mount that is under 2500 dollars. If its going to be a pure visual scope, then go the 12 if your ideas might swing photography ways definately struggle with the 10 untill you go because you can mount it on something like a eq6 and do some amazing things!

Like you said weigh up the pros and cons and you will make a decision that makes you happy.!

[GrahamL]

Yes I had a 10" for a couple of years and you can definately lug it around the house , put it in the car ect by yourself... though its still a physically large object to navigate around doorways light fixtures and such .

My 12" trusses mirror box(small box) weighs in bout the same as a solid tube 12"and I couldn't imagine wrestling that weight in a solid tube given its large size.. a trolley like a lot mention is the only way if you have the room to store and move it around .

In answer to your first question in which you bring up portabiity
being an issue Between the 10" and 12" .. go the 10".

cheers graham

[Screwdriverone]

Hi DSB,

With all you have to consider, your best bet is the SW880 10 inch SOLID tube dobsonian, from York Optical, order it online (and get the 20% discount for IIS members at that price bracket)

Cost? $799 - 20% = $639.20

Portable enough, large enough aperture, quality scope, unbeatable price at the moment.

As I mentioned to you in a PM, I would have no problem lugging the 12" SW980 around as I am over 6 foot 8, but for you, the SW880 is the best bet.

Now, stop dilly dallying around and go and buy it already! At this rate I will have my 12" before you!

Cheers :thumbsup:

Chris

[Ian Robinson]

If you've got to carry it up and down stairs , even only few , it's not the mass of the scope you need to consider , it's how physically awkward it is carry it about .

A 12" f5 (not sure what the one you are looking at is as far as f no) , will be big and awkward to carry about , even if you can easily manage lugging 20-30kg about OK , and most of us can.
Tbe tube itself will be near 5ft long, and probably 14-16" in diameter, and all the weight concentrated at one end.... that's what makes it awkward and perhaps a chore to carry it outside , perhaps even hazardous if you have to lift it or toat it up and down any stairs.
Easy to overbalance and miss your footing or trip up when lumping such a big awkward object about.

Wlll it physically fit inside your car ? that's an issue to consider if you ever want to seek out dark skies or a better horizon , or take it away with you on holidays or to starparties.

If that's not going to be a problem, go for the 12", else an 8" or 10" which will still give you a capable scope and many years of pleasure.

[Dog Star]

What Ian said!

[RobF]

Very easy to gloss over this excellent advice.

Astronomy tends to have a high drop out rate - especially after you've seen the heavens whiz around once (1 yr). You want to be having fun, not feeling guilty you didn't set up because its a pain in the butt....... :thumbsup:

[norm]

Go for the 10" inch. Its the 'safe' bet, not small, but not too large to manage.

Unless of course if you decide on a 12" collapsible.;)

The 12" inch full tube is, as Ian mentioned awkard to carry and manoeuvre unless you can have it permanently setup somewhere close to viewing or on a trolley.

Aperture is king, but so is portability imho.

Cheers,
norm

[darkskybondi]

Great advice guys. I think all that needs to be said has been said. I viewed through 8" and 9" scopes on EQ mounts tonight in Sydney's north and the Orion nebula was dark but pretty. I'd like more brightness out of mine and therefore to check out a 10" and 12" before I buy!

I take you point, Chris, but as much as I want to run out and buy one, I'd prefer to lurk at a couple more viewing sessions. My main interest is in DSOs and the forums are telling me the 12" really is the aperture that starts to show some real detail on them. Again - I have to look through a few more scopes before I decide!

Thanks again for all your thoughts, guys, and I will let you know what I decide!

- DSB

[darkskybondi]

Guys,

I am buying in the next couple of days. Still tossing up, leaving towards the 10" for sheer convenience. Seems like a good compromise. Posted a couple of last minute questions here (http://www.iceinspace.com.au/forum/showthread.php?t=39258) - be great if you could answer them!

Cheers
DSB :)

[Kevnool]

My 2 cents..... good luck with the scope that you purchase the 10" is a great scope easy to get around.

The collimator when you buy it whatever brand it is ask them at the shop to give a quick demo of its operation in a scope or yours ,as it will be invaluble later on down the track.

If the box is opened it was probably checked by staff prior to selling.

2x Barlow if you really need one at present,personally i have one but i dont use it as I only use 7mm , 14mm , 26mm.

Good luck with your observing and let us know how your getting along....cheers Kev.

[darkskybondi]

Kev - are the collapsible models more likely to collect junk like salt and dust on the primary mirror?

- DSB

[Kevnool]

your scope will collect salt over there and dust here where i live its a fact of life, protect yours a little by placing a light shroud made of cloth or lycra material around your trusses and it will also keep out unwanted light from entering the lower tube assembly of your scope.....cheers Kev.

[darkskybondi]

Purchased the 10" collapsible! (http://www.iceinspace.com.au/forum/showthread.php?t=39258) Awfully excited to try out the new toy! Thanks for all the advice. :thumbsup:

[Kevnool]

Congrats on the purchase.
You should have many a good nights viewing with your scope.
Did they at the shop give you a quick lesson in collimation b4 you took it home?
Now get yourself a planisphere to do a bit of starhopping to help find the DSO,S that you will observe.
Take it out tonight or tommorow night as the new moon was last night after that it will be moon and planets.
Cheers Kev.

[darkskybondi]

Thanks Kev!

He briefly showed me how to use the laser collimator he sold me, although I'll need to read instructions off the net again. A bit worried about safe usage of it. Also, I've read that laser collimators are generally not that great (http://www.iceinspace.com.au/63-390-0-0-1-0.html) - what do you reckon?

Here's hoping the skies clear tonight!

Cheers DSB

[Kevnool]

Laser colimators are a necessity for the astronomer.But the colimator must be colimated or centred just check the position of the beam in a v block or a lathe then turn it on point it at the wall and rotate it . this way will tell if the beam is centred.
I hope i,m not giving you a headache.
But just for tonight set it up look through it, if it looks fuzzy its out , if its a good through the eyepiece your close.
With all my scopes I give myself plenty of daylight to collimate it takes me up to 10-15 minutes.
Still let me know how you get on.
Cheers Kev.

[darkskybondi]

Hehe well I wish I had a v block or lathe but I don't! It's a GSO-manufactured collimator sold by York... is there another way to tell if it's collimated?

Also, any tips for not burning my retina with the darned thing? This is the only thing that freaks me out!

Anyways, I'll give it a go tonight. I got the demo model (there were no other 10" truss dobs in stock) so he checked it when he showed me how to collimate it with the new laser, and it was reasonably well collimated at the store (he said so; I couldn't yet tell!)

Cheers Kev,
DSB

[Kevnool]

Put it between 2 books or anything so you can rotate it.
Just dont look directly into the beam and you,ll be right.
It should be dark over there by now start observing unless you puter is outside with you.
Cheers Kev.

[darkskybondi]

Thanks Kev - sorry I don't know what you mean by "rotate it"... :newbie:

:shrug:

It's cloudy here :(

Cheers DSB

[Kevnool]

Just spin it around and look what the beam does on the wall.
If it is collimated it will be presicelly in the middle....If it does a loop then the unit is out

[darkskybondi]

You're a champ mate. I'll let you know if I get to observe tonight. Still very cloudy. Murphy's law applies, as always!

Just a reminder: :newbie:

Thanks again to you and everyone on iceinspace who've helped another n00b take advantage of affordable East Asian optics! :D

- DSB

p.s. There is some very minor dust and spotting on the primary and secondary - my scope was on display for a few weeks in the store fully expanded. I'm leaving it for now until I learn how to properly clean these mirrors (preferably without disassembling the scope, for the moment!)

[Kevnool]

Just for now use a blower bulb only to blow the mirrors but dont let the tip of the bulb touch the mirrors .
Keep asking questions.........were all here to help.
Cheers Kev.

[darkskybondi]

Yeah I should have bought a blower from him. I don't have one. Perhaps I can find something in the house to substitute.

Meanwhile the experience of checking the collimation of the collimator, and then the scope itself, ensues.

Cloud.

- DSB

[Screwdriverone]

Hi DSB.

New Telescope Rule #1: When you buy a new telescope, the skies will be cloudy at night for at least 2 weeks.

Sorry we didnt mention this before.

Lens Pen is a nice cheap mirror cleaner, it has a soft brush on one end to flick dust off, and a smooth pad on the other to wipe off gunk. Better bet (and less chance of scratching) is the blower bulb mentioned by Kev.

Cheers

Chris

[Kevnool]

Do not use a compressor or vacuum cleaner or you,ll blow crap and oil and evrything else onto the mirrors....cheers Kev.

[bmitchell82]

just a thought, would a Can of Air be any good? i know they use it in delicate electronics don't know what kind of good they are with mirrors.

[Kevnool]

On the primary or secondry i would say not a chance only because you dont know how they were filled at the factory and under what conditions..........and they had to be filled by compessed air......Cheers

[bmitchell82]

I don't think they are compressed air, i belive its C02 mmmm

[Kevnool]

No prob,s on that but the preferred and safest way is the blower bulb for dust.......With Salt and washing the primary i cannot go down that path because i plainly dont know about it to comment about it .
Happy new year all.....cheers Kev.