Considering imaging.

[Johnny Thunder]

Hi everyone.

I am considering having a go at imaging, but will probably be basic at first.

At the moment, we have a Skyliner 250px Dob. Also, an unmodded Canon 350D.

What sort of images could I realistically hope to achieve with this camera, and the mount?

What sort of imaging could I hope to achieve if I were to splash out on, say a EQ6 Pro?

And, finally, with the mount being that expensive, would I be wiser to invest the same amount of money in a mount and scope combo that would be more suitable for imaging, and also giving a better future upgrade path.

Thank you.

John.

[moondog]

With the 350D and the 250 Dob - realistically you could only manage moon images. The images with a Dob can be surprisingly good as the moon is very bright and you can take fast images. Say 1/125 - 1/500 sec at 200 - 400 ISO.

Even with a Barlow on the 250 Dob you'd probably struggle to get decent images of any of the brighter planets - you'd need a webcam.

I'd consider something like an EQ5 driven mount with a Skywatcher ED 80 refractor. A proven imaging scope and at only 600mm Focal Length it's easy to use for imaging with the DSLR.

The 250 on an EQ6 would work but imaging DSO's with it would not be easy. Also think of the weight of the set up - very difficult to move around and set up. An EQ5 and ED80 is a doddle to move and set up in comparison.

MD

[MikeD]

I use a 250px on an eq6.

If you want to image DSO's you are going to need to guide so you will also need a guide scope and guide camera.

If I were you I would get the EQ6 and a webcam and start with the moon and planets ( if there is any to be had ) and when you are ready to start working with the 350d get an 80Ed and use it for guiding with the webcam then you can guide with the 80Ed and image with the newt or swap and guide with the newt and image with the 80Ed, that's what I did except I use an starlight express HX916 to image .

if you use a DSLR on the 250 you will also need a coma corrector.

have a look at my website

http://www.freewebs.com/mikesastroimaging/index.htm

for some wecam Luna and planetary and DSO work with the 250PX/ EQ6

hope this helps

[Johnny Thunder]

Thank you for your replies guys.

I will have a look into what you have advised.

John.

[steppenwolf]

The EQ6 and 250PX make a great combination but as already stated, you will need to guide for DSO images. In addition, you need to consider the focal length which is relatively long at 1200mm - this means that it is going to be great for globulars, planetary nebulae and galaxies but, of course, not ideal for many nebulae which tend to be fairly large and you will only capture a small amount of each one. Don't let this put you off though as Mikes advice regarding the webcam and ED80 make absolute sense and you will have the best of both worlds.

[Johnny Thunder]

Thanks Steve.

My daughter is the real driving force behind wanting to try imaging, but I think we are going to have to wait a while.

Maybe we will start with quick snaps of the Moon for now.

Thank you all for your advice.

[Vega]

How do you overcome the inward focus problem with the 250px if your putting a coma corrector in the works ?

Matt

[steppenwolf]

How do you overcome the inward focus problem with the 250px if your putting a coma corrector in the works ?

Hi Matt, when funds allow ( ) I am going to get a Baader MPCC which requires a 55mm spacing between the focal plane and the corrector itself. Having borrowed one for use with my M25C CCD, I realised that I would not be able to achieve focus with the standard adapters available to me on either the SW 8" or 10" Newtonians but I have a solution!

Get an engineering company to make up a suitable length adapter with a female 'T' thread for the MPCC to screw into and whatever you need at the camera end BUT get them to make it 2" in diameter so that it fits in the Skywatcher 2" EP adapter. Assemble the camera to the custom adapter and push it into the SW 2" adapter and clap it up whilst off the focus tube. Next screw the MPCC onto the end of the custom adapter and then put the whole lot onto the focus tube.

I have got to do a final check to ensure that the outer tube of the focusser will accommodate the outside diameter of the MPCC but if it does then this will work fine. I will have the loan of the MPCC later this week and will report back on this.