Starting out in Video Astronomy - A few Questions!

[AstroAdam]

Hi All,

I've been looking at starting out in video astronomy for what seems like an age, and I've finally taken the plunge. 

I've bought a Sammy SCB-2000 on the 'bay, and am looking forward to having a mess about with it when it arrives.  I've currently got a borrowed Minitron which I'm experimenting with.   I have an 8" f/6 Newt, and a 102ED Altair Starwave - both mounted on an HEQ5 (not at the same time  )

So in the meantime, I've been doing plenty of digging, which has answered a lot of questions, but thrown up others.  If anyone can help me with these, I'd really appreciate it

1)  I'll be removing the IR filter in the Sammy.  However, as I'm going to be using in an ED refractor sometimes, do I need to replace with a 1.25" IR filter on the nosepiece to avoid star bloat?  Will this block the nice Ha that removing the stock filter lets through?  I'm kind of confused with this one...

2) As above, but this time with my Newt reflector, do I need an IR filter at all?

3) I have a 0.5x Focal reducer, but this stops the cam coming to focus in my newt.  I've bought some low profile bits and bobs, and I'm hoping that'll give me the in-focus required, but I'm yet to find out.  It comes to focus fine without the 0.5x reducer, but obviously the integration times are going to be more to get the same image, and the FOV will be smaller.  Is there any way to move the FR in or out from he chip to make it more likely I'll be able to focus?

Hopefully your collective knowledge will help me out here

Lastly - I'm using a DirectShow frame grabber (a WinTV USB stick to be precise).  Works fine with fire capture etc, but would you recommend any other software?  I'm particularly interested in the idea of real-time integration above and beyond what the cam is capable of...

Thanks in advance all, and I hope to be an active participant in this section from now on!

Cheers,

Adam

[Carl Reade]

Hi Adam I will try and answer some questions Good choice of camera.

1. Removing the stock filter on the camera will allow all the good light through. If you are using a refractor the lens cannot focus all the light spectrum equally especially IR hense the unfocused IR results in "star bloat". Yes you will benefit with an IR cut filter. Basically all the good stuff will get through and focused at the same time resulting in sharp stars.

2. The Newt does not need the IR cut filter as the mirror focuses all the light equally.

3. As you have discovered focal reducers do not work with Newts. There is a way however. There are cameras which can fit inside a 2ins holder as they are that small and nearly fit perfect and can be placed close enough to focus. The cameras are the LN300 or the Mallincam Micro. Other that this solution I have not seen anything else working.

On the plus side as you have an ED (which work fine with reducers) and a reflecter for smaller objects, you have the best of both worlds.

4. For software a good starter is Sharpcap. It has an additional software stack and has additional controls to tweak your capture, contrast, brightness etc.

Hope this is useful,

Carl

[AstroAdam]

Cheers Carl - All helpful stuff . Pretty much confirmed most of what I thought, which is good!

Been using firecapture, as I always God sharpcap really unstable, but will give it another go.

Would you recommend a particular IR cut filter?

Thanks,

Adam

[Dragon Man]

Adam, I covered this point in your other thread where you asked about IR filters:  http://stargazerslounge.com/topic/238332-iruv-filters/?p=2588996

Also, besides the LN-300 and Mallincam Micro cameras for use in Reflector Telescopes that Carl suggested, Mallincam also make a Video camera specifically for Reflectors called the 'Pro Dob II':  http://mallincam.tripod.com/id43.html

[f15p5]

Adam,

Also AVS makes an in-focus adapter for their DSO-1 cam, gets the camera inside the focuser further. It's made for dobs but I also use it in my refractor with a varioreducer to get .24 reduction. The more reduction, the more in-focus needed. It will also work with the Micro I believe.