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Confused wife needs help for hubs Christmas Telescopic present!


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I've spent days looking, reading reviews, measuring, umming and ahhing and I've decided to ask for help! {Turn left at Orion?}

Hubs has always shown an interest in all things astronomical, so I thought it was time to finally get him a scope (he's 50, I reckon he's old enough!). The scope will mostly be used indoors (he has a large loftroom/mancave with velux windows although I'm guessing initially he'll set it up I'm the conservatory) but I guess if he gets hooked, he may venture out with it (I reckon it's an unlikely but ya never know!)

The two scopes I've been umming and ahhing over are the Skywatcher StarTravel 80 (short tube) (80mm lens / 400mm focal length) and the Skywatcher Evostar 90 (90mm lens / 900mm focal length). (I think I've decided on a refractor as they give better pictures, esp of planets? Please correct me if I'm wrong!)

Looking at unboxing videos I can see the Evostar is quite large in size (it looks like a bazooka!) and I'm wondering if the size will be offputting. I like the sound of the Startravel 80 as it can become a guide scope later (if he gets hooked) but, for now, will it suffice as a decent scope?

I don't want him to be put off by blurry or nondescript images but I also don't want this huge box of tricks to sit in the corner scarily.

So I guess my main question is, would there be a marked difference between the views from these two scopes? I know there isn't much difference between the lens sizes but will the startravel short tube compromise the images?

For reference we live in the East Surburbs of London (some may call it Essex!) we have a fair amount of light pollution.

Thank you for your help in advance, it's much appreciated! Oh... And if you recommend a better/different first scope (well it's not his first, he had one as a teenager), then I'm all ears!

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Hi

Of the 2 scopes, I think the StartTravel 80mm would be easier to handle and give enough of a view e.g. the moon, planets and bright star clusters.

The 90 is much longer and harder to handle.  I had a short tube 80 and it was a very nifty scope.

He would need to use the scope outside.  They don't work well through closed windows or open ones for that matter.  The loft is a bad place as the heat rising from the house makes the view bubble with turbulence.

Good luck.

Paul

P.S.  A better alternative in the larger size is http://www.firstlightoptics.com/reflectors/skywatcher-explorer-130p.html

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I can't really help you decide between those to scopes as I'm not so familiar with them. What I can do is tell you that using them from inside the house is not going to work. Looking through glass windows will give a blurred image and with an open window the warmer indoor air mixing with the cooler outdoor air will be just as bad (if not worse). I almost sent a telephoto lens back because I thought it was broken. Turned out that the problem was me taking photos through an open window [emoji4]

If the outdoor viewing makes you lean towards the smaller scope then maybe I did help in some way.

Also - do you think he will use it mostly for visual or will he be into photography right away?

Sent from my phone using Tapatalk

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Generally speaking - aperture rules. A larger lens (or mirror, depending on the type of scope) will show more objects. Though both of the scopes you listed are nice, if portability doesn't really matter, I'd suggest the 90mm & 900mm focal-length will show objects that are a bit dimmer. And the longer focal-length, or FL, will make using higher magnification easier for targets like planets if desired. As it sounds like this will be the only telescope in the house, so it may as well be the more powerful instrument for the time being. If the intended recipient finds himself in love with this hobby - he can always re-sell and upgrade to whatever he wishes. But a 90mm F/10 (which is what we call a scope that focuses at 10X it's diameter of the lens-group.) will make a very nice gift.

So the 80mm F5 is a nice telescope. But if planets with high power views are in the mix of likely things to look at, the 90mm will make this easier. And also the Moon, if getting up close and personal with craters and mountains in the lunar vista.

I hope this helps,

Dave

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I would sugest the 90mm Evostar, bigger but it will be I think a better all round item.

The additional focal length will enable Saturn to be a feasible option to view, I am not sure tha the ST80 will deliver sufficent magnification for Saturn.

Something like the BST 8mm will give 112x that is just about enough for Saturn, Jupiter is bigger and so will be visible with something like 60x upwards, say something like a 12mm eyepiece.

Alternatives depend on the budget, these things get more costly pretty quick.

As previously said aperture tends to improve aspects, there is a 102mm Evostar and somewhere an ES 102. (ES = Explore Scientific)

I would expect the Evo 90 to be wasy to use, and not being overly large should get well used.

Which initially is a good thing.

The scope will view clusters well, double stars.

Galaxies will take a bit more selection, M31 - Andromeda - is simply too big to fit in the view of most scopes, suggest binoculars, not sure of M33 and M81, boarderline I expect.

Nebula are often faint and big, M42 - Orion - being the exception.

As information there is: http://www.essexastro.com/

Not sure if they are close or not.

Half expect to want a couple of additional eyepieces fairly soon - it is "normal". The supplied items are to get you going but they do not get you going very well. Bit like most people first car. :grin: :grin:

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Of the 2 I'd say the evo 90, my friends son has one and he manages it ... But as has been already said , from indoors the views will be ... Wobbly ! Don't be pit off though, the Moon is amazing to look at and still quite good from indoors if you open the velux window , its just way better outdoors . All the best and good luck.

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As others have said, observing from within the house - attic space or even conservatory is a no no - the images through the scope will appear to boil.

Of the two scopes you suggest the one with the wider front end will be better - the 90mm Evostar.

This scope whilst longer and heavier is still quite manageable and will show more detail on everything, it is an excellent allrounder.....

http://www.firstlightoptics.com/dobsonians/skywatcher-skyliner-150p-dobsonian.html

Good luck

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I have an Evostar 80 ED Pro, and I am very happy with it. It has a very nice and crisp image, and works perfectly as a grab and go scope.

The 90mm would be larger ofcourse, but I haven't been close to one, so I can't say how much.

I can deffinately recommend the Evostar optics.

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If your sky glow is orange coloured then there are good filters that can help with this a lot.

Do you have anywhere outside a scope can be left to cool down? The larger reflectors give poor views unless they have been left outside for a while. This is less of a problem for the refractors you have mentioned.

The best planet for viewing at the moment is Jupiter, either of the scopes you mentioned will be able to reveal bands of clouds and four moons but there will not be much detail to the clouds.

Whilst the views out of a window can be pretty bad it is possible to see things this way if it is your only option. I have done it before and it isn't ideal but it can be done. It works best if you can extend the telescope out of the window and even better if you use a dew shield to reduce the thermal currents passing the end of the scope.

Solar observing works better through windows, probably because the house is heating up when the sun is up rather than cooling down. Be sure to have a suitable full aperture filter if you try this though. Looking at the sun through an unfiltered telescope can cause blindness and destroy the scope [emoji43]

/Dan

Sent from my iPad using Tapatalk

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+1 for the 90. As has already been said, it will gather more light and will also resolve objects better (so more detail on the planets etc) without being unwieldy. Am even thinking of buying one as a grab-scope.

-1 for viewing from indoors even with the window open, it will just ruin the view. Best select a dark spot in the garden and view from there instead. I'd strongly suggest joining at least one local astro-group especially if they have regular viewing sessions. I belong to three of the four local groups and have gained a lot from them.

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Hello,

This would make for a very nice refractor and mount...

http://www.firstlightoptics.com/pro-series/skywatcher-evostar-80ed-ds-pro-outfit.html

http://www.firstlightoptics.com/vixen-mounts/vixen-porta-ii-mount.html

The mount is even on sale, and would be perfect for the refractor.  The entire kit would be very portable, too.  Smaller kits generally get used more often.

If your husband likes to tinker, then a much brighter Newtonian might be the ticket.  Much more can be seen with this one...

http://www.firstlightoptics.com/reflectors/skywatcher-explorer-150p-ds-ota.html

...and along with a choice of mount...

http://www.firstlightoptics.com/skywatcher-mounts/skywatcher-eq3-pro-synscan-goto.html...or... http://www.firstlightoptics.com/alt-azimuth/skywatcher-az4-alt-az-mount.html

With the go-to equatorial mounting, beginning astrophotography is possible, and with either the Newtonian or the aforementioned refractor.

I have several telescopes, one being this 150mm f/5 Newtonian mounted on a traditional alt-azimuth...

post-47381-0-28709100-1450619366.jpg

I take afocal photographs with it; that is, by simply holding a small camera up to the eyepiece...

post-47381-0-72278900-1450619990_thumb.j

It makes for a lot of fun.

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You don't mention budget.

If he will observe inside (not ideal but use what you have it is to do with escaping heat from the house causes the image to wobble) then something that can be portable to get it outside from the mancave then I'd look at the ST80 for fab wide views and a skywatcher 127mm mak for Moon planets and is on a AZ4 tripod or AZ3 certainly ok on the ST80.

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He would need to use the scope outside.  They don't work well through closed windows or open ones for that matter.  The loft is a bad place as the heat rising from the house makes the view bubble with turbulence.

Good luck.

Paul

Thanks Paul. I should have clarified, the loft is not a normal loft, it's a proper third floor, we just call it the loft... Long story lol! My hubs is Scottish and it's so cold in the mancave, it's almost arctic. Well maybe not that bad, but it's doesn't have a great deal of heat rising due to the insulation between floors.

I can't really help you decide between those to scopes as I'm not so familiar with them. What I can do is tell you that using them from inside the house is not going to work. Looking through glass windows will give a blurred image and with an open window the warmer indoor air mixing with the cooler outdoor air will be just as bad (if not worse).

Also - do you think he will use it mostly for visual or will he be into photography right away?

Thanks Martin. I wasn't suggesting star gazing through the closed windows, that would seem pointless! When we first moved in here, we used to sit up there star watching though the open velux windows, in our coats, with our binoculars and it was very pleasant!

For him, it would be mostly, if not all, for visual use. He's not into cameras or photography at all (that's my area, I have a couple of DSLRs and some meaty ball head tripods). This will be his hobby, just looking at the sky ;)

Could always go for FLO vouchers & think it over.  Sometimes its worth spending extra time and effort mulling over these things :)

Ack no, good idea though it is, I hate giving vouchers...they look so Rubbish wrapped under the tree! And he'd be worse at making the decision than me!

That's a reflector scope though isn't it? I had pretty much decided on a refractor, unless there was a compelling reason for a reflector.

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I would sugest the 90mm Evostar, bigger but it will be I think a better all round item.

The additional focal length will enable Saturn to be a feasible option to view, I am not sure tha the ST80 will deliver sufficent magnification for Saturn.

I would expect the Evo 90 to be wasy to use, and not being overly large should get well used.

Which initially is a good thing.

As information there is: http://www.essexastro.com/

Not sure if they are close or not.

Thanks Ronin, Planets will be his main focus...so this is a good point... I'm edging nearer the Evo 90 now. Thanks for the link, they are a long way into Essex, we're the London End.

Do you have anywhere outside a scope can be left to cool down? The larger reflectors give poor views unless they have been left outside for a while. This is less of a problem for the refractors you have mentioned.

This is why I'm heading for a refractor...

The best planet for viewing at the moment is Jupiter, either of the scopes you mentioned will be able to reveal bands of clouds and four moons but there will not be much detail to the clouds.

Whilst the views out of a window can be pretty bad it is possible to see things this way if it is your only option. I have done it before and it isn't ideal but it can be done. It works best if you can extend the telescope out of the window and even better if you use a dew shield to reduce the thermal currents passing the end of the scope.

Solar observing works better through windows, probably because the house is heating up when the sun is up rather than cooling down. Be sure to have a suitable full aperture filter if you try this though. Looking at the sun through an unfiltered telescope can cause blindness and destroy the scope [emoji43]

Thanks for the info Dan, the scope would definitely be extended out the window. Even if he was to use it in the conservatory, he'd be sitting out with it on the deck (should have clarified that too, the conservatory opens out onto a full width deck, so he'd be sitting out there, smoking, looking at stars, happy as Larry, I'd be in the warm, eat chocolate and watching Strictly!)

Either scope would be ok the 90 being a bit bigger will show a bit more.

I would advise getting the scopes on AZ 3 mount/tripod if you decide on either as this will be much easier to use than the EQ version.

Hi Glynn, thanks for the info, but I've already decided I'll be going for an EQ mount. I have plenty of ball headed tripods that tilt and swivel, roll etc and the AZ mount would feel a bit lacking in movement after using those. He used to be very keen on astronomy, physics etc so the EQ mount would be logical to him.

You don't mention budget.

If he will observe inside (not ideal but use what you have it is to do with escaping heat from the house causes the image to wobble) then something that can be portable to get it outside from the mancave then I'd look at the ST80 for fab wide views and a skywatcher 127mm mak for Moon planets and is on a AZ4 tripod or AZ3 certainly ok on the ST80.

The budget is not totally open ended, but both scopes I mentioned are around £140. I don't want to spend £200+ if it's just going to sit I the corner gathering dust.

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I guess, now I've determined that he'll be sitting outside on the deck, not obscured by windows or compromised by rising heat, that my initial main question still stands...

...would there be a marked difference between the views from the two scopes? I know there isn't much difference between the lens sizes but will the startravel short tube compromise the images?

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I would suggest that either scope will suffer if you have light pollution. It really does mean he will only see the brighter objects. If he gets the bug he will want to travel to a dark site so pick the one that is most portable.

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The short tube 80mm will (should) deliver worse images then the 90mm.

The 80mm lens will have shorter radaii (greater curvature) so I would expect there to be greater chromatic aberration and also some spherical aberration.

The radaii for the 90mm will be bigger so CA and SA will be a fair bit less.

Both the CA and SA will to the eye manifest as CA, since you are not playing with narrow band of any sort.

Both will show some CA but the 90mm should be the better visually.

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The good news is that planets are relatively bright, you can see most of them in the day if you know where to look!

The 90mm scope gathers 26% more light than the 80mm scope, the longer focal length will provide more magnification with any given eyepiece but also a smaller maximum field of view.

/Dan

Sent from my iPad using Tapatalk

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I would suggest that either scope will suffer if you have light pollution. It really does mean he will only see the brighter objects. If he gets the bug he will want to travel to a dark site so pick the one that is most portable.

Good point. Meaning the Startravel would make more sense.

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The short tube 80mm will (should) deliver worse images then the 90mm.

The 80mm lens will have shorter radaii (greater curvature) so I would expect there to be greater chromatic aberration and also some spherical aberration.

The radaii for the 90mm will be bigger so CA and SA will be a fair bit less.

Both the CA and SA will to the eye manifest as CA, since you are not playing with narrow band of any sort.

Both will show some CA but the 90mm should be the better visually.

Ok... Makes sense. I'm now looking at the StarTravel 102... Shorter, more portable for when the LP gets too much for him but a bigger lens.

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The good news is that planets are relatively bright, you can see most of them in the day if you know where to look!

The 90mm scope gathers 26% more light than the 80mm scope, the longer focal length will provide more magnification with any given eyepiece but also a smaller maximum field of view.

/Dan

Sent from my iPad using Tapatalk

Would the field of view be so restricted as to lose positioning easily? I know what looking through extended photography lenses are like, I get lost looking at birds in the trees!

What would you choose if you were at the beginning of your Astronomy journey again? The Startravel or the Evostar?

Also, just looked at the Celestron 90mm, same kinda specs as the Evostar, is one manufacturer better than the other?

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