Using a DSLR to record video rather than Webcam?

[billdan (Bill)]

Hi cpoc,

The only disadvantage using a tracking DOB or any other Alt/Az mount is field rotation. This is worst near Zenith so don't image near there, only image as the stars rise towards Zenith and again when they fall towards the the West. If you limit your exposure times to 20 secs you will be safe from any rotation within each sub. Some parts of the sky (due East or West) you can do 2 minute subs.
Other solutions to this problem to get longer subs, is a field rotator or an equatorial wedge.

However for serious imaging you need a guide camera to stop star drift in the frame, and not all Alt/Az mounts have guide ports.


Cheers
Bill

[thegableguy (Chris)]

Though it is a great scope for great observing, portability and ease of use, two things to bear in mind:

- Dobs, even go-to Dobs, aren't great for photography. Though the target may stay centred, the view will rotate. You'd only get exposures of around 15 seconds before getting streaky stars.

- You can't change the focal length as that's a function of the curve of the primary mirror.

However, it would be fantastic for observing.

For the same money you could pick up a second hand HEQ5 mount and 8" reflector. Not quite as portable, not quite the magnification or aperture... but still pretty good for observing, and absolutely brilliant for photography.

You kinda have to choose between observing and photography I'm afraid! I went from ED80 to 8" reflector because the ED80 wasn't much chop at observing; the reflector does a good enough job for me.

[cpoc]

Originally Posted by thegableguy

Though it is a great scope for great observing, portability and ease of use, two things to bear in mind:

- Dobs, even go-to Dobs, aren't great for photography. Though the target may stay centred, the view will rotate. You'd only get exposures of around 15 seconds before getting streaky stars.

- You can't change the focal length as that's a function of the curve of the primary mirror.

However, it would be fantastic for observing.

For the same money you could pick up a second hand HEQ5 mount and 8" reflector. Not quite as portable, not quite the magnification or aperture... but still pretty good for observing, and absolutely brilliant for photography.

You kinda have to choose between observing and photography I'm afraid! I went from ED80 to 8" reflector because the ED80 wasn't much chop at observing; the reflector does a good enough job for me.

I like the sound of the second option there... a HEQ5 and an 8" reflector... I think I could be happy with that... I will keep my eye out... thanks for the advice.

[croweater (Richard)]

Baarx1963 (Malcolm) has an orion sirius mount (same as heq5) for sale in iis classifieds. Just under that Cushellen has a 8" f5 newtonion with 80mm guide scope and a coma corrector and some other acc. At $800 each is probably ticking all your boxes. Would be excellent setup to start with I think at good price. Cheers Richard.