Ideas for ultra-compact telescope?

[Buqibu]

Hi all,

I'm currently in a foreign country where I have the opportunity to buy a telescope (at home this isn't the case and ordering isn't worth it because import fees double or triple the prices). I currently have a Celestron Astromaster 102AZ, which I learned on and have been using for a good 3 years. However, the limitations and relatively poor quality of that telescope and especially it's mount are starting to really bother me, so I want an upgrade. Here comes the problem: I can only carry with me on the plane 2 backpacks. One of these would be dedicated the the scope. So I am looking for something that can fold down in some way or something that is a very (very!) short OTA, and something that is lighter than 10kg when fully setup. So far I've come to the conclusion of either a TableTop Dobsonian or some sort of small Cassegrain. I would like the aperture to be no smaller than 100mm, and preferably around 5 inches so it can be a visual upgrade from my astromaster. Budget at max would be around 450-500 euro. I want to know if this is at all possible, or if I'm asking for too much haha. Thank you for reading and I appreciate all replies,

Kind regards,

Buqi

[Elp]

Unless if you've gone Japan or the USA I don't know if a scopes worth importing in person from retail, but only you'd be able to judge the savings.

[John]

Celestron C5 SCT''s are compact and quite light at 2.8kg for the optical tube.

 

 

[happy-kat]

The dobsonian bases on table top dobs do not collapse down and any tripod legs do not collapse down small enough for your backpack I don't think. If you are handy at making things you could make a dobsonian base at home for a telescope if you decided to get a mak/sct. There might be importation taxation too when carrying new items in.

Edited May 8 by happy-kat
Corrected spelling

[bosun21]

A 127 Skywatcher Maksutov OTA and a carbon fibre tripod. Nice and light. Also airplane friendly and cheaper than the the C5.

[Gfamily]

Probably not what you're thinking of, but the SeeStar50 is so compact and light that you might want to consider it as a realistic alternative to a compound telescope (to use the terminology I learned at A level).

 

[Buqibu]

Thank you all for the replies, I'll consider the input

[AstroMuni]

18 hours ago, Buqibu said:

Budget at max would be around 450-500 euro.

So you are looking for a scope for visual use (not photography), right?

Have you considered something like this https://www.firstlightoptics.com/startravel/skywatcher-startravel-102-az3.html

EDIT:

OR

You could purchase just the OTA and an AZ4 mount which is available on offer at the moment for £99 https://www.firstlightoptics.com/offers/sky-watcher-az4-alt-az-astronomy-mount-with-aluminium-tripod.html.  This combo might just tip you over the 10kg though

Edited May 9 by AstroMuni

[Louis D]

Watch out for import duties if you bring it back with you.  I have no idea what your De Minimis Value is for your home country (it's $800/day in the US), but you could end up paying quite a bit upon return.

[Buqibu]

3 hours ago, Louis D said:

Watch out for import duties if you bring it back with you.  I have no idea what your De Minimis Value is for your home country (it's $800/day in the US), but you could end up paying quite a bit upon return.

I suppose I'd get it out of the box before taking it with me. Will that negate import fees?

[Buqibu]

7 hours ago, AstroMuni said:

So you are looking for a scope for visual use (not photography), right?

Have you considered something like this https://www.firstlightoptics.com/startravel/skywatcher-startravel-102-az3.html

EDIT:

OR

You could purchase just the OTA and an AZ4 mount which is available on offer at the moment for £99 https://www.firstlightoptics.com/offers/sky-watcher-az4-alt-az-astronomy-mount-with-aluminium-tripod.html.  This combo might just tip you over the 10kg though

Hmm, would that be an upgrade from my current scope? I'm assuming that mount is better than mine but the achro OTA at that focal ratio has me a bit worried

[LondonNeil]

The st80/102/120 are good scope for the cost.  I've a st120 and yes there's a purple fringe around the moon but it still gives good,  sharp images.   Not in the league of sn apo, but nowhere near the cost. 

[Louis D]

1 hour ago, Buqibu said:

I suppose I'd get it out of the box before taking it with me. Will that negate import fees?

It's going to depend on the country.  Many require a list of equipment that is verified as pre-owned when exiting/entering the country, so it doesn't get hit with import tariffs.  This is especially important for photographers and videographers who may have tens of thousands of dollars of equipment with them as they travel on assignments.

[Buqibu]

39 minutes ago, Louis D said:

It's going to depend on the country.  Many require a list of equipment that is verified as pre-owned when exiting/entering the country, so it doesn't get hit with import tariffs.  This is especially important for photographers and videographers who may have tens of thousands of dollars of equipment with them as they travel on assignments.

Ah ok, makes sense. I'll have to look into that

[AstroMuni]

14 hours ago, Buqibu said:

Hmm, would that be an upgrade from my current scope? I'm assuming that mount is better than mine but the achro OTA at that focal ratio has me a bit worried

At f4.9 its a faster scope compared to what you have (f6.5 ?) so images will be a lot better. You could add the included barlow to slow it down. Ofcourse if your budget allows you could go for the ST120 at f5 and around 4kg. IMO you should spend money on a better mount as that will make your viewing experience a lot better. If one of the carbon fibre tripods fits into your budget then they are easy to carry on flights as well.

Edited May 10 by AstroMuni

[ollypenrice]

7 hours ago, AstroMuni said:

At f4.9 its a faster scope compared to what you have (f6.5 ?) so images will be a lot better. 

I don't follow this. Visual images in budget refractors tend to be better in slower optics and this kind of telescope is possibly the worst of all options for imaging, with pretty well everything wrong. Poor colour correction, a lot of field distortion, a sag-prone focuser, etc.

Olly

[AstroMuni]

On 10/05/2024 at 17:40, ollypenrice said:

I don't follow this. Visual images in budget refractors tend to be better in slower optics and this kind of telescope is possibly the worst of all options for imaging, with pretty well everything wrong. Poor colour correction, a lot of field distortion, a sag-prone focuser, etc.

I was under the impression that OP was using for visual only. If you are saying that slower scopes would be better even for that then I need to do more reading up
🙂

[Tiny Clanger]

On 08/05/2024 at 19:58, Buqibu said:

Hi all,

I'm currently in a foreign country where I have the opportunity to buy a telescope (at home this isn't the case and ordering isn't worth it because import fees double or triple the prices). I currently have a Celestron Astromaster 102AZ, which I learned on and have been using for a good 3 years. However, the limitations and relatively poor quality of that telescope and especially it's mount (my bold) are starting to really bother me, so I want an upgrade. Here comes the problem: I can only carry with me on the plane 2 backpacks. One of these would be dedicated the the scope. So I am looking for something that can fold down in some way or something that is a very (very!) short OTA, and something that is lighter than 10kg when fully setup. So far I've come to the conclusion of either a TableTop Dobsonian or some sort of small Cassegrain. I would like the aperture to be no smaller than 100mm, and preferably around 5 inches so it can be a visual upgrade from my astromaster. Budget at max would be around 450-500 euro. I want to know if this is at all possible, or if I'm asking for too much haha. Thank you for reading and I appreciate all replies,

Kind regards,

Buqi

If it's the mount & tripod that you have identified as the main weakness in your setup, get that sorted out first. I assume that your current telescope has a standard dovetail rail ? A new mount compatible with a standard Vixen type dovetail will be less delicate to pack into a rucsac than a telescope, and many photo tripods close down into short, compact packages. I'd suggest as well as upgrading mount and tripod you could consider adding one of the Baader filters that reduces chromatic aberration to make your current 'scope work better for you https://www.firstlightoptics.com/achromat-semi-apo-filters.html A filter would be certainly be easier to pack than a new 'scope !

You've not said what country you live in, or what country you are visiting, or how much you have to spend, so it's difficult to be specific about exactly what you might choose to buy, but photography equipment shops are more common than astro ones, so you will probably be able to see some tripods on display, maybe even handle them. Most quality photo tripods can be bought without a photo head, and have a 3/8" protruding screw to fix a head to. A lot of alt az heads with an under 8kg carrying rating use that 3/8" screw fitting too.

As to heads which fit those photo tripods, I've used a 102 refractor a similar size to yours on a skywatcher AZ5 and found it vibrated too much, the same for a premium alt az head with a similar tall vertical arm arrangement. I've had far better experiences with the more compact alt az mounts which hold the OTA out at the side of the head, like this https://www.firstlightoptics.com/alt-azimuth-astronomy-mounts/berlebach-castor-ii-altazimuth-mounting.html

and even this, which was rather strained and very close to the stated carrying capacity with a 102mm f7 on it, but OK at lower magnifications, and very much improved by use of a counterweight https://www.firstlightoptics.com/alt-azimuth-astronomy-mounts/omegon-az-baby-mount.html

I've not owned one of these, but read that they have been used with 100mm fracs, and have the advantage of slow motion cables (which you can easily remove to pack) https://www.firstlightoptics.com/alt-azimuth-astronomy-mounts/sky-watcher-az-pronto-alt-azimuth-astronomy-mount-wo-tripod.html

 

On 09/05/2024 at 18:30, Buqibu said:

I suppose I'd get it out of the box before taking it with me. Will that negate import fees?

Import regulations, taxes and fees vary enormously from country to country, you need to check your home country government advice on personal imports from the specific country you are visiting. Taking it out of the box certainly won't negate any fees, it might avoid them, or it might get you in trouble if an inquisitive customs officer notices you are trying to evade paying ...

[ollypenrice]

2 hours ago, AstroMuni said:

I was under the impression that OP was using for visual only. If you are saying that slower scopes would be better even for that then I need to do more reading up
🙂

Briefly, faster optics are harder to make, so more expensive. With reflectors the problem lies in minimizing optical distortions which require ever more sophisticated grinds and improved mechanical parts. With refractors, colour correction becomes harder as F ratios diminish and at some point only a triplet lens can deliver.

In both cases, accepting a slower F ratio will, in principle, result in better views when budgets are tight.

Olly

[Buqibu]

9 hours ago, Tiny Clanger said:

If it's the mount & tripod that you have identified as the main weakness in your setup, get that sorted out first. I assume that your current telescope has a standard dovetail rail ? A new mount compatible with a standard Vixen type dovetail will be less delicate to pack into a rucsac than a telescope, and many photo tripods close down into short, compact packages. I'd suggest as well as upgrading mount and tripod you could consider adding one of the Baader filters that reduces chromatic aberration to make your current 'scope work better for you https://www.firstlightoptics.com/achromat-semi-apo-filters.html A filter would be certainly be easier to pack than a new 'scope !

You've not said what country you live in, or what country you are visiting, or how much you have to spend, so it's difficult to be specific about exactly what you might choose to buy, but photography equipment shops are more common than astro ones, so you will probably be able to see some tripods on display, maybe even handle them. Most quality photo tripods can be bought without a photo head, and have a 3/8" protruding screw to fix a head to. A lot of alt az heads with an under 8kg carrying rating use that 3/8" screw fitting too.

As to heads which fit those photo tripods, I've used a 102 refractor a similar size to yours on a skywatcher AZ5 and found it vibrated too much, the same for a premium alt az head with a similar tall vertical arm arrangement. I've had far better experiences with the more compact alt az mounts which hold the OTA out at the side of the head, like this https://www.firstlightoptics.com/alt-azimuth-astronomy-mounts/berlebach-castor-ii-altazimuth-mounting.html

and even this, which was rather strained and very close to the stated carrying capacity with a 102mm f7 on it, but OK at lower magnifications, and very much improved by use of a counterweight https://www.firstlightoptics.com/alt-azimuth-astronomy-mounts/omegon-az-baby-mount.html

I've not owned one of these, but read that they have been used with 100mm fracs, and have the advantage of slow motion cables (which you can easily remove to pack) https://www.firstlightoptics.com/alt-azimuth-astronomy-mounts/sky-watcher-az-pronto-alt-azimuth-astronomy-mount-wo-tripod.html

 

Import regulations, taxes and fees vary enormously from country to country, you need to check your home country government advice on personal imports from the specific country you are visiting. Taking it out of the box certainly won't negate any fees, it might avoid them, or it might get you in trouble if an inquisitive customs officer notices you are trying to evade paying ...

Thank you very much for the detailed response. I will consider all these points

[LukeSkywatcher]

Sumerian. I think that's what they are called. A large Dod in its own "suitcase".

Edited May 13 by LukeSkywatcher

[paulastro]

On 08/05/2024 at 21:36, John said:

Celestron C5 SCT''s are compact and quite light at 2.8kg for the optical tube.

 

 

Plus 1.  A 5inch SC is the most compact 5inch scope you can get.  I still have one in case I need to travel abroard  somewhere - and of course in this country when space is at a premium. For any of the anti-SC brigade, remember they were good enough for NASA to take into space.

[radiofm74]

On 08/05/2024 at 20:58, Buqibu said:

Hi all,

I'm currently in a foreign country where I have the opportunity to buy a telescope (at home this isn't the case and ordering isn't worth it because import fees double or triple the prices). I currently have a Celestron Astromaster 102AZ, which I learned on and have been using for a good 3 years. However, the limitations and relatively poor quality of that telescope and especially it's mount are starting to really bother me, so I want an upgrade. Here comes the problem: I can only carry with me on the plane 2 backpacks. One of these would be dedicated the the scope. So I am looking for something that can fold down in some way or something that is a very (very!) short OTA, and something that is lighter than 10kg when fully setup. So far I've come to the conclusion of either a TableTop Dobsonian or some sort of small Cassegrain. I would like the aperture to be no smaller than 100mm, and preferably around 5 inches so it can be a visual upgrade from my astromaster. Budget at max would be around 450-500 euro. I want to know if this is at all possible, or if I'm asking for too much haha. Thank you for reading and I appreciate all replies,

Kind regards,

Buqi

You might even get away with a (used) C6. I paid mine 400€, and it's a full 6" of visual goodness in a tiny package. Well below your 10kg fully setup. My precious little visual travel scope … Add in a f/6.3 reducer and you get almost 2 degrees of FoV in a 1.25" eyepiece.