four inch refractor .. or .. ?

[jellies]

Another first telescope question
I don't have a home with much possibility for home observation so if it isn't somewhat portable (taking it for a weekend trip), it just won't get used. Having a photography hobby, I'm going to be drawn to astrophotography but viewing is the priority for now.

I'd like to get a better view of the planets first, Despite observing from Sydney (on the coast) the other week I spent an hour flat on my back looking at Saturn through IS binoculars, I could see the rings, at least the two bumps they made in the orb, and watched the atmosphere cycle from that heat haze wiggle, to still again. I've been on some star gazing tours as well, the last one was in Hawaii where they setup a bunch of scopes and bus you to the top of the mountain. That was memorable. Clubs are not really my thing though.

I'm drawn to 4" refractors like the Tak 102, or the Tele Vue NP101 because I often read "if I was only allowed one telescope" it would be this kind. I enjoy even the pleasure of possessing some quality Japanese kit.

On the other hand I also read aperture wins, so it isn't clear to me if (or why) an 8" meade SC would be actually be less practical to use, and then maybe I'd enjoy planets/moon equally, trading off quality for size but get more DSOs ?

Oh also one last wrinkle is since I do some wildlife photography, the NP101 is an interesting option because I buy a telescope but get a free pin sharp mega zoom lens thrown in for free.

Should I go for a Takahashi complete, or start with a much cheaper higher aperture scope that is still portable, but spend on the mount?

thanks

[Kunama]

I love my Takahashi TSA120 and the views it gives but I would not recommend it for a first purchase unless and until you have had the opportunity to try a few different scopes of differing focal lengths, apertures and types.

By asking this question you are unleashing a wild horde of opinions about newtonians in Dobsonian mounts of varying sizes, then the refractor brigade will tell their story. The only way you will make any sense of it is to get out to a gathering of insomniacs with scopes and look at and through them and then decide for yourself based on how much room you have in your car, how much time you have for setting up, how much money you really want to dispose of etc.

My system of a high quality refractor on a high quality alt-az mount with excellent eyepieces works for me. Some days I just want to spend an hour viewing a specific object and can carry the kit out in one piece to cool down, have a beer or 2 and be ready for superb quality views.

I also love the 'ownership factor' of such a nice bit of kit. But that's just me, your priorities will vary.

Good luck !!!

PS> Astro imaging is a totally different animal altogether, I would advice against heading down that murky path too soon.

[jellies]

Ok I just read through this topic:
http://www.iceinspace.com.au/forum/s...ight=takahashi

and now suspect my question has been answered before, and the consensus formed that:
* unless one lives in dark skies, spend less by going for a big aperture non refractor, for now.

Unfortunately the counter-examples given: 10" dobsonian, etc, seem to be much less portable than a 4" refractor. With its sheer size it is going to stay in the backyard, not go to the country for a weekend in a travel case.

Lets look at a 10" newtonian, for example a Celestron C10 for $3000: the total weight is 42kg.. again, it isn't going to travel easily

What about an 8" SCT, example weight, 19kg of which 8.6kg is the tripod/mount. This seems sort of equivalent to a 4" Takahashi in terms of portability, but maybe the 4" refractor is still "ready to go" versus an 8" SCT.

So now I've got an issue: for urban skies a huge scope is better but my garden is not blessed with much sky view. To have one for camping or a weekender, I need something that is going to be somewhat portable.

4" refractor ? or is there something else for similar money, and more aperture, that is no less practical..

[jellies]

Originally Posted by Kunama

I love my Takahashi TSA120

Thanks, but - the 120 is quite a bit more scope than the 102, right?

I think boiling my question down a bit more the issue I have is I want the best longevity (rather than being a stepping stone) for the least size/weight/impracticality.

[Kunama]

....... Welcome to the mayhem ..........

With longevity in mind ............ I think most will advice you to expect be a "2 scope" owner. The portability and imaging capability of a 4" refractor on a decent mount combined with the light-grabbing qualities of 10" reflector in a Dobsonian cradle will give you a great sample of both worlds.

I think if I was buying just one scope for my personal needs it would be a Takahashi Mewlon 210 or 250 with 2 mounts (an EM200 and a T-Rex)

[jellies]

thanks,

Yeah, while digging, I am now seeing this question comes up again and again.

Obviously if one has the flexibility of a house with a garden with a wide view and somewhat ok skies, there are a lot of opinions and choices that apply but I am worried the correct answer for my situation is: don't buy anything. To buy a smaller aperture high quality scope is the wrong scope to start with, to buy a large economical scope will also be a waste, because it can't be easily moved from my useless for skies home.

I'm much desiring the astro physics 130EDFGT which is a compact 5.1" refractor and unfortunately also close to unobtanium. I like it because it breaks down so it can even go by air, the aperture is usefully larger than 4", etc etc.

edit:
The mewlon 210 plus mount indeed looks nice - at 22kg total, there is weekend portability. And I just read through this
http://www.cloudynights.com/item.php?item_id=2791
now I am desiring it more.

[Steffen]

You could also get a high-quality Rumak type Maksutov-Cassegrain, in 6" or so, from Intes-Micro. They're very portable (the OTA of mine weighs 6.5kg), certainly more portable than the tripod/mount to go with it.

I'm not into astro-imaging, though, if you want to do that it may be better to start with a decent mount and put an ED80 on top for now.

Cheers
Steffen.

[Wavytone]

jellies,

You need to clarify your needs somewhat. You want visual, then mention photography, you know aperture wins but you want this to travel... all to some extent conflict as there's no such thing as a "do-it all travelscope". As indicated below it is better to accept that you will need two scopes, possibly three, each optimised for a specific role:

- one that is a travelscope (and I would ask what do you want this for ?)
- one for photography (terrestrial or astro, up to you)
- one optimised for maximum visual fun.

By way of example:

Many years ago I used to travel to see solar eclipses and in many respects the ideal kit for this was a 4" Meade SCT on a camera tripod. It would pass as cabin luggage, and for years was my travelscope. By comparison the 100mm f/7 refractor I now have is too big for a camera tripod and relatively unused - it is big enough to be inconvenient. This is why the small fast 60 and 80mm scopes are popular, but a 4" SCT is even better. It's also the reason the Questar 3.5" will be forever popular, if you can afford one.

For terrestrial photography take care with focal length - anything beyond 700mm is going to give so much magnification that atmospheric turbulence will spoil resolution. A small spotting scope is often sufficient; a 100mm refractor is total overkill and impractical.

Astrophotography... requires an equatorial mount. A good one, at least an EQ6 or better, and bear in mind the optics optimised for astrophotography aren't always optimal for visual - I'm referring to both fast refractors (f/7) and fast-focal ratio reflectors with huge secondary obstructions.

Visual... the best option is either a dobsonian, 8-10" aperture, around f/5 (wide field, low power stuff), or if your pockets are a bit deeper an altaz SCT or a Maksutov which is capable of giving really good high-magification views of the planets and smaller deep sky objects. In addition the closed tube means the mirror coatings will last a lot longer.

Just be aware that cheap scopes aren't designed to last for a long time - many have a limited life before you will need to rebuild them or replace them entirely.

[LAW (Murphy)]

I would recommend a 10" f/5 collapsible dob, I think the Skywatcher is around $800. In my opinion it would be more portable (taking into consideration setup time) than a Frac on an Alt-Az mount, and the aperture will satisfy you longer.

When you're buying scopes it's either visual, or imaging. There aren't too many setups capable of satisfying both needs, EQ tracking mounts are cumbersome and awkward for visual use, but Dobs and Alt-Az tripods aren't capable of the longer exposures for Astrophotography, so it's all a trade off.

[pluto (Hugh)]

I got my setup as I wanted to extend my photography hobby. I had been doing heaps of widefields and I was ready for more FL and an EQ mount. Like you I live in Sydney and can't setup at home so I wanted everything to be portable.
I ended up getting a SW ED80 and an EQ5goto. These have been great so far and if I did it again I'd probably choose the same (maybe I'd get an HEQ5 but I do love the portability of my EQ5).
Of course my ED80 isn't the best scope for visual observing but, with the right eyepiece, I enjoy good sharp views of the moon, sun, Jupiter and Saturn as well as some of the brighter clusters.

I sometimes wish I had caught the visual observing bug instead of the much more time consuming, complicated and expensive astrophotography bug but I, like many others I'm sure, derive great enjoyment and satisfaction from producing astro images and all that goes into it.

My $0.02, good luck!

[jellies]

Originally Posted by Wavytone

You need to clarify your needs somewhat. You want visual, then mention photography, you know aperture wins but you want this to travel...

thanks for the reply.
I'm prepared to give up the astrophotography - which were expressed as more as a nice-to-have-the-option - as it is obviously something that requires many hours first in the back garden. And I just don't have that luxury. The idea of travelling somewhere then spending ages imaging I think means you gotta be able to do it reliably from home first - & a variety of equipment is required and must be debugged.

Having to travel and having portability doesn't mean I need something to fit in the overhead bin of a plane but it does mean that when the family spends time outside the city (by car), not having to think TOO much about whether the telescope can come along too. After all, if I can't use it in my garden except for the moon, it won't be used at all if it is a pain to load into the car.

As for terrestrial photography again that seems to be something the Tele Vue NP101 is very good at, they even advertise it that way - but clearly it is a unique bonus quality not something to search for.

SO -- I think I have to get into visual first, before astrophotography.

The mewlon 210 on a NEQ6 could actually work out well. Too much to spend as a start, but I want to skate to where I'll be in a year if I enjoy it. Also I do hope to get that cottage in the mountains one day - then a quality bit of kit will live to see that day.

[Poita (Peter)]

I'd get a hold of a 4" refractor first and try it out under some skies before makign a decision.
I had a very nice Lomo triplet 4" scope that gave views every bit as nice as a 4" Tak, pin sharp, great views etc. but even under the darkest skies it didn't float my boat after a while. I had a little C8 at the same time, and I tended to take it with me more often after a while. Great planetary and moon views, the extra magnification and light gathering won me over most nights, and it was extremely portable.

Whereabouts do you live? It will probably be quite possible to borrow or at least get a look through various scopes under darker skies before you buy. I'd strongly recommend doing so before plonking down the money.

[ZeroID (Brent)]

You seem to be intent on jumping into the expensive bracket real quick and you may end up owning something you get to use very infrequently. One of the advantages of buying cheaper secondhand, not quite so clever hardware in your early astro 'career' is that you can easily flick them on with little loss and they can be good learning experiences to understand your own direction later.
My Grab&Go is just an 80mm F5 Achro, $200 worth on a reasonably solid photo tripod and in dark sites it's amazing what it can see. It doesn't do bad photos either with a CLS filter killing the minor achro effect it can have. It all fits in a alum case the size of a small suitcase with EPs and bits. That and a tripod and I'm good to drive all of NZ.
A Tak or Mewlon or whatever is a lot of money to splash out as an experiment to see if you like it.
I have the 10" and the Lunt 90 but they sit on the mount mostly. The little 80 gets to travel quite a bit.

[Terry B]

I have used various scopes similar to what you are thinking about and will give you my opinion.
I have a 127mm refractor and it is sort of portable. It has a big box to protect it and the mount needs to be carried as well. All of this fits in the back of my SUV or a hatchback but I wouldn't like put it across the back seat of a sedan. I have also used a 120mm refractor and it was more easily transported.
Both give similar views. Nice crisp but small views of the planets. Deeps sky is pretty diappointing though. Viewing planets is OK but there is often only 1 visible and it gets pretty boring after a while.

I also use a VC200L. It is lightweight and when matched with a mount like a GP or GPDX mount is more portable than the refractor. It does fit on the backseat of a car. I just seat belt the OTA in the seat.
It is now permanently in my observatory so isn't moved any more but has been in the past.
I have also used a 10" dob. It fits in the back of a car just and is the quickest to set up.
The views through the 200mm or 10" is much more pleasing than the refractor. Many galaxies are identifiable along with lots of planetary nebs.
The smaller refractors essentially restrict you to the messier catalogue only.
Planets are also OK through the bigger scopes. Maybe not as crisp as the refractor but take magnification better.

I hope this helps.
Cheers

Terry

[jellies]

thanks for more replies.

Yes, I do give the impression that I'm ready to open my wallet and I know how that looks. Like an 18 year old shopping for a ferrari, right? what a young idiot. He is going to kill someone

That said, I'm actually quite cautious when it comes time to committing. Naming equipment and budgets in forums is very different than actually spending the money. I'm still 50:50 on buying anything at all.

The logic that is driving me to admire refractors is that they repeatedly get named as a grab and go scope: something that cools down faster, doesn't need collimation.

I'm a bit computer mad and the idea of having an EQ mount with low tracking error that I can bolt a DSLR to, and stack images is attractive for the sheer complexity of it plus it also is a sort of virtual aperture bump: even if the viewing isn't amazing, the image might end up being so.

ALL THAT SAID, ZeroID you are absolutely right and before spending a lot on a fancy mount and a fancy refractor or mewlon, if I can get some kind of a taste by buying a decent 80mm and a tripod, perhaps secondhand to get more bang, for less than the price of a few tak accessories I'd be a fool not to do that. And plus, if I don't take any further steps, that little setup would be perfect for kids to look-see on weekends out of town. So that's what I'll do.

Actually the ferrari comparison isn't really a perfect parallel. When you get your first car, it is enjoyable even if it is a junker. No young man gets keys to something crap, drives for a bit, and thinks "well, this sucks, I'm not gonna drive anymore". But plenty of people buy a telescope that doesn't wow them either in manufacturing quality and/or viewing quality, and then give up. I'm an old guy it takes a lot more to wow me - to make me want to put in the hours. Also, mass produced engineering, where you can feel or see the large tolerances and cheaper materials, makes me sad. So there is some of that too.

[Merlin66 (Ken)]

I don't think in the last 50 years there's not a telescope I haven't tried...
The "holders"
- A great 4" Genesis...mind you the 80EDpro comes close....
- A 10" f5 Dob - but I did sell it - bumma!
and at least a HEQ5pro (or better the NEQ6pro) mount.
That will basically do everything, without going overboard.

Remember the "extras" eyepieces, guide scopes, cameras, software etc etc will cost, over time, as much as the scopes!!!

[dannat (Daniel)]

keep in mind if you get a short tube achro -the planets will show lots of colour -which can be distracting.
for this reason i have a 5" maksutov (etx125 OTA) its really only good for lunar/planets because its long focal length means a small field of view ,
the scope is very portable -i have either a manual alt/az mount for it or a small computerised goto mount -the tune only weighs 3kg so is light & packs up inot a 40x20x10 cm bag

[jellies]

Originally Posted by dannat

keep in mind if you get a short tube achro -the planets will show lots of colour -which can be distracting.

Do you mean colour halos around the planets?

[Steffen]

Originally Posted by dannat

i have a 5" maksutov (etx125 OTA) its really only good for lunar/planets because its long focal length means a small field of view

Really? With a 24mm Pan you'd get 0.8˚ TFOV or thereabouts, which is more than wide enough for the vast majority of DSOs.

Cheers
Steffen.

[Draco (Draco)]

Hi Jellies

alas, i too was in your shoes not too long ago... without a scope, ready to jump to rash decisions just so that i could own my very own scope (i am not saying you are like this but that I was ). I was even willing to take out a credit card debt to get my very first Goto SCT which would have set me back around $3k.

But then I joined an astronomy group and got to handle a few scopes there. I got told about dobsonian mounts and equatorial mounts, about how dobs are so much nicer for newbies. After all this, I got stuck on getting a 10" dob since it was sub $1k and could fit my car (small hatchback). 10" is not too small that I will have to upgrade anytime soon and was still good to enjoy the good things out there. However, then I saw the 12" meade collapsible dob and just wanted that one since I saw many more years of use in that. I wanted to get as much years out of my purchase as possible.

Finally, I sat down one day and evaluated my situation. I wasn't as knowledgeable on telescopes as I wanted to be and didnt want to end up purchasing something that I would not be able to use a few months after and then have to sell it off for cheap. So i decided to get a second hand cheap telescope. I found one on ebay for sub $150.. a 114mm 900mm focal reflecting telescope on equatorial mount. It is not the best scope but it still gives me really good views. Since getting it I have learned alot about whats out there, how to focus on to things and more importantly .. WHAT TO AVOID IN MY NEXT SCOPE. In astronomy, I have learnt the hard way, good things dont come cheap and if you are willing to wait and save, you will get what you want in the end. I myself, chose to take the hard road since I want to learn the skies before jumping onto a goto scope (btw I will end up getting a SCT in the end )

Everyone is different, but everyone does go through the newbie urge to make a quick purchase. My recommendation would be to get something second hand that fits most of your needs and which is not too expensive then by the time you have mastered that, you will have a better standing of what you want.

my 2c worth