Consultation on a MEADE telescope

[Matias Saibene]

Hello everyone.
I'm about to buy a telescope MEADE ETX80 and I have some questions:

1.- I see planets with this telescope with good definition?

2.- I see stars or nebulae with good definition?

Specifically what I want is to see some planets, like Venus, Mars, Jupiter, and I get a good enough resolution to distinguish. And I want to see nebulae.

Greetings to all.

Sorry for my bad english.

http://www.meade.com/etx/specifications

 

[Piper]

The ETX series of telescopes are a great series of telescopes, but to answer your question, it depends on how you define "good definition." People are so used to seeing Hubble images, and images from other massive telescopes, that when they look through even a large telescope like mine (a 10-inch Meade LX-200), that they are often let down. With something like the one you're getting, you'll get a fantastic view of the moon, you'll definitely see nebula (I particuallarly like planetary nebulas) and galaxies, you should be able to see some of the cloud bands around Jupiter, and colour differences between areas on Mars. A lot of what you'll be able to see also depends greatly on where you are viewing from. From where I live near the city, I see very little definition in something like the Andromeda galaxy, but out in the country, I can see incredible detail and definition. But don't expect to see any colour in the nebulas/galaxies, to the human eye, they all look grey.

 

[Matias Saibene]

Thank you very much for your prompt response.

I currently have a Meade telescope, but much smaller (is to see the moon, and the earth landscapes and nothing else).

I mean "good definition" with the following:

-If I can distinguish Saturn (or Jupiter) of any bright spot in the sky (in my current telescope Júpiter looks like a star).

-If I can see some nebula and distinguish of any bright spot in the sky.

In short, I want see an object (of the mentioned) different from a bright spot, as we currently see with the eyes.

Excuse me if I can not express properly.

 

[sorindafabico]

I won't say if the model is good or bad, but I intend to give you some insights to choose an appropriate telescope.

- Definition is proportional to aperture. More aperture, more definition - and more light coming in. Aperture is the most important specification.

- Magnification depends on the eyepieces you use. Above 300X the image usually starts to degrade. You calculate magnification as (telescope focal distance)/(eyepiece focal distance).

- You can get good views of the planets with 200X, but you need a good aperture to see details like the red spot or the Cassini division (I can't tell you if 80mm is enough because I never used telescopes with less than 200mm of aperture - all I can tell you is that the rings are majestic at 200mm ).

- Choose bigger focal ratios for planets and smaller for deep sky. F/5-F/6 is versatile if you want both. Focal ratio is (focal distance)/(aperture).

- Be aware of light pollution. If you live in Buenos Aires, forget objects fainter than magnitude +9 even if you buy a fancy 300mm telescope.

- Before purchasing a telescope, go to an observatory that is open to general public (universities usually have one). Ask to use every model avaliable and compare them.

- This is important: do you know how to locate objects in the sky? If you don't have a fancy GoTo, you need to know the positions of objects, many you can't see with naked eye. Be sure to study celestial charts - it's wonderful when you locate clusters like Omega Centauri in a light polluted city.

- Also, be sure to buy a telescope you can carry around. If your observatory is at your home, weight and size are of little importance, but if you intend to go to the countryside, be sure to buy something that, well, fits inside your car.




Having said all that, buy the best telescope you can afford.

 

[Matias Saibene]

I won't say if the model is good or bad, but I intend to give you some insights to choose an appropriate telescope.

- Definition is proportional to aperture. More aperture, more definition - and more light coming in. Aperture is the most important specification.

- Magnification depends on the eyepieces you use. Above 300X the image usually starts to degrade. You calculate magnification as (telescope focal distance)/(eyepiece focal distance).

- You can get good views of the planets with 200X, but you need a good aperture to see details like the red spot or the Cassini division (I can't tell you if 80mm is enough because I never used telescopes with less than 200mm of aperture - all I can tell you is that the rings are majestic at 200mm ).

- Be aware of light pollution. If you live in Buenos Aires, forget objects fainter than magnitude +9 even if you buy a fancy 300mm telescope.

- Before purchasing a telescope, go to an observatory that is open to general public (universities usually have one). Ask to use every model avaliable and compare them.

The specifications say it has a clean opening 80mm (3.15 ") and 400mm focal length.

To find objects in the sky I use Stellarium.

Unfortunately Buenos Aires is very far from where I live (at a distance of 700km) and not have an observatory nearby, but in my area there are almost no visual pollution (it's a turistic beach less than 10,000 habitants).

 

[sorindafabico]

Lack of light pollution is an advantage, you're lucky for living in a small town. The lack of a nearby observatory isn't a no-go, of course, but then you'll have to trust on the internet

With 400 mm you'll get a max magnification of about 100X without barlows. That's enough for "big" planets (Venus, Jupiter, Saturn). I don't know about Mars, but should be ok in opposition. With kit eyepieces you'll get 41X and 15X, so I think you'll soon be looking for shorter eyepieces (or a barlow) if you want to see the planets.

The level of detail is aperture-dependant.

I did a little research to know what you can see with 80 mm (and a good magnification):

- Phases of Venus are easily seen
- Syrtis Magna region; polar caps as small dots on Mars
- Equatorial bands on Jupiter (I don't know about the red spot) and, of course, the moons
- Saturn: the Cassini division and Titan, Iapetus, Rhea and Thetys

The faintest object you can see with 80 mm in a clear sky is aroung mag +11 (enough for most Messier objects).

It seems to have GoTo capability, so you won't need to guess where the faint objects are.


I personally don't like refractors (they need expensive lenses to deal with chromatic aberration). What about a dobsonian?

 

[Matias Saibene]

Lack of light pollution is an advantage, you're lucky for living in a small town. The lack of a nearby observatory isn't a no-go, of course, but then you'll have to trust on the internet

With 400 mm you'll get a max magnification of about 100X without barlows. That's enough for "big" planets (Venus, Jupiter, Saturn). I don't know about Mars, but should be ok in opposition. With kit eyepieces you'll get 41X and 15X, so I think you'll soon be looking for shorter eyepieces (or a barlow) if you want to see the planets.

The level of detail is aperture-dependant.

I did a little research to know what you can see with 80 mm (and a good magnification):

- Phases of Venus are easily seen
- Syrtis Magna region; polar caps as small dots on Mars
- Equatorial bands on Jupiter (I don't know about the red spot) and, of course, the moons
- Saturn: the Cassini division and Titan, Iapetus, Rhea and Thetys

The faintest object you can see with 80 mm in a clear sky is aroung mag +11.

It seems to have GoTo capability, so you won't need to guess where the faint objects are.


I personally don't like refractors (they need expensive lenses to deal with chromatic aberration). What about a dobsonian?

In my country get this telescope is very difficult because imports are closed. In fact I have searched a lot for thi telescope and now is the only one in my area (and around 100km).

The seller told me he had Barlow lenses, and AstroStar system with a database of over 1,000 objects.
Besides being able to see objects that you mention, I'd be more than satisfied:thumbup:.

 

[Codz]

I use a 6 inch Orion Dobsonian, and live in a relatively light polluted area, but I can easily discern the major cloud bands of Jupiter, the Great Red Spot, and the Galilean moons. As for Saturn, the rings and Cassini division are visible, as well as the larger of Saturn's moons. The Andromeda galaxy, the Orion nebula, Pleiades, and many other major DSO's are also visible in detail.

EDIT-Just read the last post.

Anyway, the telescope you're looking at should be sufficient for Jupiter, Saturn, and the major DSO's.

 

[Matias Saibene]

Thanks for the help and advice of all. In this day I could buy the telescope. But unfortunately for me the sky was covered with rain clouds, and make one last request:

How much will it cost to buy a HAARP to control the weather?:rofl:
It's obviously a joke.

Greetings and thanks.:tiphat:

 

[kuddel]

How much will it cost to buy a HAARP to control the weather?:rofl:

You would miss that extraordinary feeling you get, when you've finally had a perfect night after many 'not so good' ones
:tiphat: