Deciding on Telescopes, Tripods and such

[ReInvented2012]

Hey everyone, I have been looking into getting some new equipment (first set of equipment ever actually). I already have a Canon Rebel T3i with the kit lens 18/55mm f3.5-5.6 IS. I have decided to also order a 70/300mm f4-5.6 IS USM (maybe the Tamron version) but definitely this size/length. Everyone was a huge help in helping me decide on a lens so I had to come back and ask for more advice.

I am interested in astrophotography and cannot decide one a telescope and tripod. Some telescopes that I am looking at come with a tripod and some dont. I am wondering if I need a 2nd tripod if I get a telescope with a tripod (thats the first ?).

I am going to post some links for you all to check out what I am looking at and help me make a decision based on the equipment I already have and what I want to do (photograph stars, clusters, planets etc).

Reflectors:
Orion Telescope w/Tripod
Orion w/o Tripod

Refractors:
Orion w/o Tripod
Orion w/ Tripod

Tripods: (will I need one if I buy a telescope w/ a Tripod?
Manfrotto
Vanguard

Those are all the ones I was considering. Price is a huge factor, so if you have other suggestions please dont make then $1,000 telescopes or tripods . I also wanted to know of other things I may need to help me get started and take great pictures (filters, different lens, etc) I also know that I will need a T-ring and T-adapter to hook the camera up to the telescope.

Below are 2 images I took last night with a cheap tripod and my kit lens on the Canon T3i. I couldn't upload the best ones bc of size, so if someone can also let me know how to attach larger photos or resize them that would be a huge help. Im putting some on my flickr page as well. Also I know when taking photos of space people talk about focusing to infinity but apparently this lens I have doesnt and I had to take tons and tons of photos to try and get a clear picture. Any help with this problem would be great.



Thanks in advance for all your help. Peace & Happiness.

 

[KmH]

Please edit your post and put some space between the 2 photos.
We can click on attached photos to display them at a larger size.
You cannot attach larger photos by uploading them directly from your computer, but you can post (URL inside IMG tags) larger photos if they are hosted somewhere online.

For astrophotography the bigger the telescope aperture the more light the telescope can gather.
If you double the diameter of the aperture you gather 4x more light.

Consequently reflectors are generally preferred over refractors
Reflectors cost less per inch of aperture because they use a mirror rather than a lens.
A mirror only has to be shaped and figured on 1 side while a lens has to be shaped and figured on 2 sides making it cost less to make a mirror.
Mirrors also have fewer optical aberrations that have to be accounted for than lenses do, another cost savings.

The front lens in a decent refracting telescope is usually a doublet (2 lenses) or a triplet (3 lenses) group of lenses. The additional lenses are needed to correct optical aberrations. So a triplet group then consists of 6 sides that have to be shaped and figured while a mirror still only has 1.

However, refractors have advantages for shooting objects close to home (in our solar system), like the planets and the Moon.
Reflectors are preferred for deep sky objects (outside our solar system).

Many camera lenses are difficult to set at infinity because most of them have an infinity symbol (&#8734 rather than a tick mark. The infinity setting varies somewhat for each lens.
If you auto or manual focus the lens on a distant terrestrial object and then switch the camera/lens to manual focus so the focus cannot be changed by the AF system you should be very close to if not at infinity focus for that lens.
In other words, for all intents and purposes for normal focal length photography something 5 miles away is at infinity.

Another consideration for astrophotography and focus sharpness is how still or turbulent the atmosphere is and how high in the sky your subject is.
Straight up we look though just one thickness worth of our atmosphere. The closer we get to the horizon the thicker the atmosphere becomes. At the horizon we are looking through about 3x worth of atmosphere thickness.
As we look closer to the horizon the atmosphere also becomes more turbulent.

FWIW - There is an upper limit to the size a refracting telescope can be made. Because we have to look through a lens it can only be supported around it's edge. Bigger than about 40 inches the front lens/lens group gets so heavy the lens/lens group changes shape as the telescope is moved to point to different parts of the sky. The changing shape distorts the image the lens delivers.
So the largest refracting telescope in the world is the Alvan Clark designed 40" refracting telescope (first used in 1893) at the University of Chicago's Yerkes Observatory - http://en.wikipedia.org/wiki/Yerkes_Observatory

 

[ReInvented2012]

Please edit your post and put some space between the 2 photos.
We can click on attached photos to display them at a larger size.
You cannot attach larger photos by uploading them directly from your computer, but you can post (URL inside IMG tags) larger photos if they are hosted somewhere online.

For astrophotography the bigger the telescope aperture the more light the telescope can gather.
If you double the diameter of the aperture you gather 4x more light.

Consequently reflectors are generally preferred over refractors
Reflectors cost less per inch of aperture because they use a mirror rather than a lens.
A mirror only has to be shaped and figured on 1 side while a lens has to be figured on 2 sides making it cost less to make a mirror.
Mirrors also have fewer optical aberrations that have to be accounted for than lenses d, another cost savings.

However, refractors have advantages for shooting objects close to home (in our solar system), like the planets and the Moon.
Reflectors are preferred for deep sky objects (outside our solar system).

Many camera lenses are difficult to set at infinity because most of them have an infinity symbol (&#8734 rather than a tick mark. The infinity setting varies somewhat for each lens.
If you auto or manual focus the lens on a distant terrestrial object and then switch the camera/lens to manual focus so the focus cannot be changed by the AF system you should be very close to if not at infinity focus for that lens.
In other words, for all intents and purposes for normal focal length photography something 5 miles away is at infinity.

Another consideration for astrophotography and focus sharpness is how still or turbulent the atmosphere is and how high in the sky your subject is.
Straight up we look though just one thickness worth of our atmosphere. The closer we get to the horizon the thicker the atmosphere becomes. At the horizon we are looking through about 3x worth of atmosphere thickness.
As we look closer to the horizon the atmosphere also becomes more turbulent.

Thanks for the help. Fixed the spacing, and thanks for that tip, I will just post links to the exact image on flickr from now on.

From what you are saying about focusing on distant objects that requires the telescope right, because obviously with my current set up I cannot focus on anything. That's what I was trying to figure out, without a telescope, how can I get a focused picture without taking 10 pictures of the same area and refocusing each time, is that even possible with the lens I have?

And if I want to take both planet and deep space pics would the reflector or refractor be best? Im looking for all around use to give me a wider range of capabilities. You were also mentioning atmosphere, would there be a filter to help with that to make for clearer photos?

Also do you happen to have an answer as to whether or not I need a telescope tripod and an extra one for the camera specifically? I would like to get away with having less equipment since I travel a lot.