Starting to take Pictures of the stars

[ve1drg]

I am about to start taking pictures of various objects in the sky and am wondering if I just attached my Canon 5dMark111 to my Esprit 120 if simple pictures of the moon and galaxies etc will work?  I am aware that many people take multiple exposures of various objects and use photoshop etc to make it all work,  but if I just took a simple picture through my scope with my 5dMark111 - shouldn't I get a decent picture?

Of course I would have to work out the exposure time but I am only thinking of snapping one picture and not multiple ones.

Any thoughts please.

[Leveye]

Without using a real tracking mount and at that focal length you won't get that much exposure time before trailing starts. Wide angle lenses with a DSLR are better suited for use on just a tripod. A high iso say about 800-1600 for about 25 seconds works great for widefield star shots

[stelios_t]

Not sure if you have an EQ mount or not. Without an EQ mount, I'd abandon serious hope of anything except the Moon. 

But if you *have* an EQ mount, then there's no need at all to fear multiple images. There's no need for Photoshop, the freeware Deep Sky Stacker will allow you to combine your images with no real work on your part.

Still, yes, you should be able to take decent single images with unguided exposures up to 45 seconds or so, assuming you get a good polar alignment. You may be able to go higher (in exposure time) with a great mount, but if you want to do that you should probably guide.

Try it out for yourself. You need a T-ring and prime-focus adapter. Set camera to Manual, shutter to Bulb, disable any de-noising, ISO 800 works best, and take a picture! Make sure you use a remote shutter activator (or a program like Backyard EOS to control the camera via the USB cable). If you have a laptop, I'd strongly advise downloading Backyard EOS (free 30-day trial, $35 thereafter) which will let you take one or multiple pictures and also help you with the *very* tricky part of focusing with a scope attached (much harder than you'd think, and you'll eventually need to get (inexpensive) or make a Bahtinov mask for that purpose).

[stelios_t]

Without using a real tracking mount and at that focal length you won't get that much exposure time before trailing starts. Wide angle lenses with a DSLR are better suited for use on just a tripod. A high iso say about 800-1600 for about 25 seconds works great for widefield star shots

Forgot to add: Take RAW (or RAW+jpeg). That way you'll be able to post-process them if you ever feel like it.

[ve1drg]

I must apologize.  I am using my Esprit 120 on an AZEQ6 which is a very nice motor driven mount.  What my question was really about was do I have to take many pictures of various objects in the sky to get a decent picture?  Or can I simply attach my 5dMk111  and snap the picture.  Just one picture at the correct exposure.  Shouldn't that get me a decent picture of objects like M33 or M31 etc.. etc..

Just curious.  And I am about to give this a shot..

[poogle]

Some deep space objects will give you a decent picture with only one exposure (depending on your expectations and the length of the exposure).

You could try imaging star clusters (like M13) or the orion nebula M42.

The AZEQ6 is indeed a very nice mount. When polar aligned try snapping a 30 second exposure at ISO800 or 1600 and I'm sure you'll be very pleased with the result.

You might have to give it a few tries to get the focus right. Without a bahtinov mask or laptop at hand you might want to try focusing on the moon or a distant street light and then slew to the object you want to image.

Hope this helps, and keep the questions coming. I'm sure you'll be bitten by the astrophotography devil 

By the way, have you got all the required adapters to connect the DSLR to the scope?

/Patrik

[stelios_t]

I must apologize.  I am using my Esprit 120 on an AZEQ6 which is a very nice motor driven mount.  What my question was really about was do I have to take many pictures of various objects in the sky to get a decent picture?  Or can I simply attach my 5dMk111  and snap the picture.  Just one picture at the correct exposure.  Shouldn't that get me a decent picture of objects like M33 or M31 etc.. etc..

Just curious.  And I am about to give this a shot..

The issue with one vs. many exposures: If you had a perfect mount, that was 100% polar-aligned and had no periodic error, then you could do one long exposure and be done with it. But for real-life, and without guiding, you'll find out that after as little as 45 seconds you start getting oblong stars even with a decent polar alignment effort. And 45 seconds is not long enough to bring out DSO's to their full glory. This is why it's better to take multiple images and combine them (stack them). The stacking process reinforces the DSO. 16 x 45 sec is not as good as one perfect 16x45 = 12 min exposure would be, but it'd be much better than a single 45 second image.

Additionally, if you have light pollution, you may find out that prolonged exposures just wash out your DSO in sky glow, even with a light-pollution filter. But multiple smaller exposures just work.

Taking and combining exposures is really much simpler than it sounds, if you have a laptop, Backyard EOS and Deep Sky Stacker. And the benefit of being able to focus via BYE can't be overstressed.

[ve1drg]

Some deep space objects will give you a decent picture with only one exposure (depending on your expectations and the length of the exposure).

You could try imaging star clusters (like M13) or the orion nebula M42.

The AZEQ6 is indeed a very nice mount. When polar aligned try snapping a 30 second exposure at ISO800 or 1600 and I'm sure you'll be very pleased with the result.

You might have to give it a few tries to get the focus right. Without a bahtinov mask or laptop at hand you might want to try focusing on the moon or a distant street light and then slew to the object you want to image.

Hope this helps, and keep the questions coming. I'm sure you'll be bitten by the astrophotography devil 

By the way, have you got all the required adapters to connect the DSLR to the scope?

/Patrik

OK on your thoughts.  I will do as you say and see what happens.  I am aware that there is a need for multiple exposures etc..  but I was thinking if I could keep it simple with just ONE shot,  I would be happy.

Thanks  and I will let you guys know what and how things went.