astrophotography

[sidewinder]

Greetings I need help seting up and taking images. I have a canon SLR with live view and a T-ring for it. How do you get Mag. from a camera with out a lens, on a back of a scope with out an eyepeice? Please help....

Clear Skies

[arad85]

The telescope acts as the lens. Just a fixed focal length/aperture one. You don't have the concept of "magnification" when taking photos, just field of view the 'scope/camera chip sees. The resolution of the image is then defined by the number of pixels on the chip.

[sidewinder]

so with an 11" celestron and a canon SLR 10.1 MP I should be able to get really good photos right...

Clear Skies

[Merlin66]

Yes, is the basic answer, BUT......

I think you'll find the f10 focal length is a bit too much and you'll probably add a x0.63 reducer to bring it down to f6.3.

You'll need a couple of additional adaptors if you use the reducer to get the spacing between it and the camera CCD to around 110mm

Do you have a remote release? To reduce vibration a remote like the TC80 is usually used on the Canon's.

Ken

[sidewinder]

thank you for the advice but could you please speak english. I am really new at the imaging part. I know photography pretty well and i know my scope OK but put them together and i'm lost. thank you

Clear Skies

[arad85]

The problem with an 11" F/10 scope is it's like having a 3m long 11" lens. The area of sky this will cover is very small and for any faint objects your tracking will have to be completely spot on otherwise you will get star trails. Additionally, as it is F/10, it is slow therefore you'll have to point it for a very long time to get decent images. A f/6.3 reducer will turn the 'scope into an F/6.3 11" scope - still effectively 2m long but a bit easier to deal with. You'll only see a few attempt to image with a DSLR and an 11" as it's really, really difficult.... Most people start out astrophotography the other way around - come at it from wide angle lenses or longer length photography lenses and work up.

[sidewinder]

thank you for dumbing it down a little. I think I understand. I'll look for the reducer thank you again.

Clear Skies

[Merlin66]

OK....

1. Do you have a remote release cable to activate the shutter without pressing the button on the camera?

If not you'll probably need one ie Canon TC80 ( google will find it)

2. Although you can take a image using the C11 without any extra lenses you'll find that it acts like a fixed 2800mm f10 telelens.

It would be better if you add an "extra" lens to the rear of the telescope, infront of the camera body. This "focal reducer" can then convert your scope to a 1760mm f6.3 telelens which will give a larger field of view and brighter images.

Hope it helps.

Ken

[SlipperySquid]

I'm just at this point of taking piccies.....oh the fun and joy...and headaches....and kicking of the dog!

I'm sure all the teeth gnashing I'm going through will be worth it in the end and I'll have some photo's to be proud of .....but the jargon and learning curve is astronomical (pun intended )..... I just want to point....shoot....have photo published in Sky at Night....is it really to much to ask for!

Love Squid ....All the gear and absolutely no idea.

[sidewinder]

Squid you about sumed it all up there.. all the gear and no idea what I'm doing....Cheers

Clear Skies

[David Pavlich]

Here's a book by Jerry Lodrigus. He's a whiz at DSLR imaging:

A Beginner's Guide to DSLR Astrophotography

This will put you on the right track to the dark side.

David

[jgs001]

The other one to look at is Steppenwolf's book, Making every Photon Count. It's a well written easy read, that guides you nicely through it all. It doesn't come with a guarantee of being published in the Sky at Night though

[sidewinder]

cheers

Clear Skies

[barkis]

The advice about reducing the native f10 of your C11 is of course very sound indeed Jon. Except to say, that at f10, it will take you in to the moon some way, and under the right conditions, such as crescent phase, and phases up to full, some nice images can be achieved. Care must me taken with focusing, and the point about a remote shutter release is very desirable, as any vibration transmitted to the telescope will ruin a potentially good picture.

Just take your time, there's no rush. All the sky's residents aint going anywhere. Although if your weather is anything like it is in the UK, then you have to take the opportunities when they arise.

Ron.

[sidewinder]

I hear that about the skies. We have had a few clear nights here in the US but mostly cloudy at least where I am at. Cheers

Clear skies