Astrophotography Noob

[DeadMan]

Hi all!

This is my first post

I am after some advice on astrophotography using my old meade 8" lx200 classic.

My wife just bought a nice new Canon EOS 400D digital SLR camera, so I thought I would give it a go with some prime focus astrophotography using a Meade #62 T Adaptor and Eos T-ring.

Basically any advice in this area would be appreciated as I am a noob.

Cheers

DeadMan

[Tinkerbell]

Welcome to SGL DeadMan

You will be restricted to 30 seconds at first if You are alt/az mounted but if you have a wedge you are off and running. If you don't already have a remote for the 400D it is worthwhile getting one as without it 30 seconds is the maximum the camera will allow. Next a 6.3 focal reducer will give you a bit wider field of view and longer exposures will suffer less if your mount has tracking errors which they all do to some extent. :? Its a great way to get into imaging and can be a lot of fun but be prepared to bite your tongue a few time as it can be a little bit frustrating at times Thirty seconds doesn't sound very long but if you were to take 30 x 30 seconds shots and then stack them using DeepSky Stacker you will be amazed at the results.

Hope this helps.

[Vega]

The biggest challenge I had with my 400D was focusing (especially on dimmer objects). Be prepared to spend a lot of time on it. It's hard to see anything through the viewfinder, especially if on a dark area of sky. There are a couple of method's for focusing..

1. Inexpensive, time consuming method

Take lot's of test photo's and review them on screen but use the zoom feature and zoom on to a star. Re-adjust focus and review until you get it just right.

2. Expensive but effective method

Buy some software (I use ImagesPlus which has many other uses for DSLR photography) that has focussing software in it. This reviews the shots I take for me giving me a score for how well focussed the stars are in the image. I keep adjusting till it gives me the best score.. brilliant!

I would recommend the RC-1 remote controller for taking photo's without touching the camera/scope. Otherwise, again go down the software route like I have whereby you can tell the camera what exposure length to take and click from the laptop. If you use a special serial cable you can even setup multiple long exposure's (well over 30 secs if required) at different ISO setts at the click of a button and listen to it click away a ton of exposures while you go get a cuppa... 8).

Obviously for doing any DSLR photography of anything dimmer than the moon, the exposure lengths required means you need the scope to have the ability to track the stars otherwise all of your photo's will show the stars as streaks as they move across the sky.

Hope this helps

Matt

[DeadMan]

Thanks for the advice Moon Plodger and Vega! I was wondering about the Alt/Az part, I guess I need to find a second hand wedge for the serious shoots.

Could you go into more detail as to why it will only be good for 30 second shots?

I think the last time I used my scope was about 4 years ago using a Phillips toucam pro and Meade auto focuser to take pics of the moon and planets.

Vega, the software sounds interesting, how much is it?

Checklist so far:

1, Wedge

2, F6.3 Focal reducer

3, RC-1 remote control for DSLR

4, focus aiding software

5, deepsky stacker for lots of 30 second shots

Cheers

DeadMan

[Tinkerbell]

Thanks for the advice Moon Plodger and Vega! I was wondering about the Alt/Az part, I guess I need to find a second hand wedge for the serious shoots.

Could you go into more detail as to why it will only be good for 30 second shots?

I think the last time I used my scope was about 4 years ago using a Phillips toucam pro and Meade auto focuser to take pics of the moon and planets.

Vega, the software sounds interesting, how much is it?

Checklist so far:

1, Wedge

2, F6.3 Focal reducer

3, RC-1 remote control for DSLR

4, focus aiding software

5, deepsky stacker for lots of 30 second shots

Cheers

DeadMan

The 30 seconds is really only a guide as some times it will be a lot less. If I remember right it is a thing called Field Rotation. When a scope is alt/az mounted the scope can track the stars all night long using both motors and visually You wouldn't notice a problem but with a camera attached you would notice pretty quickly that the orientation of the camera with regard to the motion of the sky was out of sink. If you take an image at 30 sec and then one at 90 sec and compare the outer stars on the 90 sec one they would look elongated radially. If you then mount the scope on a wedge and try the same exposures the 90 sec one would just be brighter than the 30 sec one with no elongation of the outer stars (hopefully) . The reason is that by mounting on a wedge you have aligned the Dec axis with the pole and allowed for the Earths rotation so the mount then only uses the RA drive to track the sky and if you watch the tube for long enough you would see it slowly rotate in sink with the patch of sky that you are imaging so no field rotation and longer exposures can be taken. Hope this makes sense. :?

[Vega]

Vega, the software sounds interesting, how much is it?

DeadMan

Here's where you get it from... (Forgot to add link... now added )

It also allows multiple long exposures to be taken via a serial cable

Matt

[DeadMan]

Thanks for the advice Moon Plodger and Vega! I was wondering about the Alt/Az part, I guess I need to find a second hand wedge for the serious shoots.

Could you go into more detail as to why it will only be good for 30 second shots?

I think the last time I used my scope was about 4 years ago using a Phillips toucam pro and Meade auto focuser to take pics of the moon and planets.

Vega, the software sounds interesting, how much is it?

Checklist so far:

1, Wedge

2, F6.3 Focal reducer

3, RC-1 remote control for DSLR

4, focus aiding software

5, deepsky stacker for lots of 30 second shots

Cheers

DeadMan

The 30 seconds is really only a guide as some times it will be a lot less. If I remember right it is a thing called Field Rotation. When a scope is alt/az mounted the scope can track the stars all night long using both motors and visually You wouldn't notice a problem but with a camera attached you would notice pretty quickly that the orientation of the camera with regard to the motion of the sky was out of sink. If you take an image at 30 sec and then one at 90 sec and compare the outer stars on the 90 sec one they would look elongated radially. If you then mount the scope on a wedge and try the same exposures the 90 sec one would just be brighter than the 30 sec one with no elongation of the outer stars (hopefully) . The reason is that by mounting on a wedge you have aligned the Dec axis with the pole and allowed for the Earths rotation so the mount then only uses the RA drive to track the sky and if you watch the tube for long enough you would see it slowly rotate in sink with the patch of sky that you are imaging so no field rotation and longer exposures can be taken. Hope this makes sense. :?

That makes perfect sense! thanks for the clarification