You'd get 10/1 on this old nag.

A perfect image Dave
You say it was taken with a 10" F4, is this a newtonian?
I also think this is definitely one in not the best you've taken so far.!
Looking forward to seeing more.

A perfect image Dave
You say it was taken with a 10" F4, is this a newtonian?
I also think this is definitely one in not the best you've taken so far.!
Looking forward to seeing more.

Thanks for the kind comments everyone

Yes Dave 10" f/4 Newt with a baader coma corrector.

It's a funny thing that sometimes you can have just one of those nights (like last night) where everything just works like it should. Then you can have another night where you end up with nothing. If you guys saw the number of images which never end up on these boards. Maybe I'll set up a 'hall of shame' like Anthony

I heard recently that the canon 300d chip has a peak QE of only about 10%. Don't know how true this is though.

WOW! This is news to me!

I was reading up on the cheapest SBIG camera, the ST-402. In an 8" f/10, it can apparently capture mag 14 stars with a one second exposure and mag 18 at 60sec! Amazing! QE of this chip is 85%.

I think this applies to all of the SBIG cameras. My ST-2000XM has a QE around 50% and the manual specifies precisely the same info about a mag 14 star (1 sec exposure) and a mag 18 star (60-sec exposure).

wow dave,
you can really can see the benefits of all that new equipment super image :shock: :shock: :shock:

I think this applies to all of the SBIG cameras. My ST-2000XM has a QE around 50% and the manual specifies precisely the same info about a mag 14 star (1 sec exposure) and a mag 18 star (60-sec exposure).

If one camera is more sensitive than another, surely the magnitude of star they capture would be different, would it not?? Unless there's another reason.