What lenses if any any?

[Thor92]

Hello all, me again,

So I've got my 150DPS on it's EQ5 mount with coma corrector and cannon T ring all set up for my 450d.

Using it mainly as a visual setup at the moment (obviously without the coma corrector) but I'd like to take a venture into beginner astrophotography now I know the body fits on nicely and uses the scope as it's lens but is there any camera lenses that can be used in combination with the scope and camera? Or is it best to stick with the body only ?

I know that may sound like a silly question but I've seen conflicting accounts when looking so far but that may be my lack of understanding.

Thanks all. Couldn't have got to this point without people's help

J

Edited September 13, 2019 by Thor92

[celestron8g8]

Is that scope a Newtonian ? 

[MattJenko]

When you attach your 450D, you are in effect using the 150PDS as the lens, you wouldn't attach another. If you did, you would end up in a world of distortion and pain as you try and focus the camera on the focal point of the telescope - don't do it, let alone the issues in trying to attach it all together.

Because you are using the scope as a prime lens, the focal length is fixed, as is the aperture, so the DSLR options you have are ISO setting. This is always good for some debate, but you want to keep it as low as you can. I have a 450d as well, and found that 400 or 800 is the best compromise between sensitivity and image crushing noise.

The field of view you have is also fixed, which makes finding objects to frame actually very easy, just look at astronomy.tools and choose objects and see how they might fit. I actually think the Skywatcher coma corrector is a x0.9 reducer as well, so the real field of view might be bigger, but this will be close enough.

 

[Thor92]

2 hours ago, MattJenko said:

When you attach your 450D, you are in effect using the 150PDS as the lens, you wouldn't attach another. If you did, you would end up in a world of distortion and pain as you try and focus the camera on the focal point of the telescope - don't do it, let alone the issues in trying to attach it all together.

Because you are using the scope as a prime lens, the focal length is fixed, as is the aperture, so the DSLR options you have are ISO setting. This is always good for some debate, but you want to keep it as low as you can. I have a 450d as well, and found that 400 or 800 is the best compromise between sensitivity and image crushing noise.

The field of view you have is also fixed, which makes finding objects to frame actually very easy, just look at astronomy.tools and choose objects and see how they might fit. I actually think the Skywatcher coma corrector is a x0.9 reducer as well, so the real field of view might be bigger, but this will be close enough.

 

That is exactly what I thought and the answer I was looking for! Perfect detailed response aswell. Thanks I only asked because I can across a thread talking about lenses for astrophotography however I think they meant astrophotography without a telescope.

Thanks again

[almcl]

44 minutes ago, Thor92 said:

I only asked because I can across a thread talking about lenses for astrophotography however I think they meant astrophotography without a telescope.

 

You certainly can use your Canon 450d with a lens and no telescope.  A 50mm lens can give nice widefield views of, say, the Milky way and anything up to about 200 mm focal length will be pretty forgiving of tracking errors and can provide good views of some of the larger Deep Sky Objects, but perhaps for the moment just concentrate on getting used to imaging with the 150 PDS?  It should an exciting and rewarding experience!