Uranus with moons Oberon & Umbriel - mag 15 in 3 secs!
Hello,
I managed to grab a nice image of Uranus and two of his moons, Oberon and Umbriel earlier this morning (12:20am). I used the C9.25 at prime focus with my SBIG ST7E ccd camera.
What is remarkable is that I picked these up with a 3 second exposure! The image is a stack of 3 x 3 secs and we are already down at mag 15! These cooled SBIG cameras are quite special.
I suspect that Uranus’ moons will be available to anyone with an 8 inch scope and a cooled or sensitive ccd camera, so why not go out and give it a try. It would be nice to see one in colour.
Dennis, two of those objects were visible in the 16"with 13mm Nagler and 2x barlow=242x mag, I did not know which was a moon, but could see them quite plainly, I was seeing stars down past 15th mag in my supernova search.
At astrofest a few years ago an astronomer from Space telescope science institute, named Eric Karkoscka(spelling) showed that you could see some moons of Uranus with a medium to large telescope, in fact I think that he used Zac's 20" on the night.
The seeing last night was about 8-10 Trans 7.5-10 Temp 6.5
.... These cooled SBIG cameras are quite special. ....
Mmmmm ST7 sensitivity.... agreed, they are quite special. I'm often amazed what a 5 sec exposure will show, I know that if I'm looking for an NGC and it's shape is not visible in 5 seconds then I'm off target.
Now if only I had colour at that sensitivity
Neat image btw too, I wasn't aware the moons were so easy to see, not that I'd ever thought about it I have to admit..
Dennis, two of those objects were visible in the 16"with 13mm Nagler and 2x barlow=242x mag, I did not know which was a moon, but could see them quite plainly, I was seeing stars down past 15th mag in my supernova search.
At astrofest a few years ago an astronomer from Space telescope science institute, named Eric Karkoscka(spelling) showed that you could see some moons of Uranus with a medium to large telescope, in fact I think that he used Zac's 20" on the night.
The seeing last night was about 8-10 Trans 7.5-10 Temp 6.5
Hi Ron
Strewth - for one moment I thought you had come over to the "dark side", replying to a post on ccd imaging!
Seriously though, your report is an excellent account of what can be achieved visually by experienced observers with larger aperture 'scopes - well done! My own experience has been that seeing these types of special or unusual objects visually, leaves a deeper impression and is more personally rewarding than grabbing an image.
Very nice image Dennis! It would be great to stack more exposures and reduce some of that noise.
Hmm, I dunno Mike....the grainy look gives it that "right on the edge" look, a bit like those marvelous, early images from the first wave of Lunar explores that graced the newspapers in the early 1960's. Kinda make it look like it was difficult to grab, on the bleeding edge of technology as it were; whereas in reality I was sipping a cup of tea and browsing IIS and the jetstream map whilst listening to dido at the time, dressed in my new beaut freezer suit with wool lined boots.
Strewth - for one moment I thought you had come over to the "dark side", replying to a post on ccd imaging!
Seriously though, your report is an excellent account of what can be achieved visually by experienced observers with larger aperture 'scopes - well done! My own experience has been that seeing these types of special or unusual objects visually, leaves a deeper impression and is more personally rewarding than grabbing an image.
Cheers
Dennis
Thanks Dennis, as you can see from another forum I do take some images, but not on the fantastic quality of yours
I have to let the little grey cells do my interpritation through the eyepiece
but when it all boils down it is all astronomy and we love it
Hi Dennis, pushing the envelope as we've come to expect. Great shots! When did the SBIG turn up in your gear?
cheers,
Hi Robert
Thanks! I bought the ST7E (old parallel version) from Eddie Trimarchi in 2002 or 2003. I'm still waiting for the stunning images from it, but it seems Eddie's magic touch never rubbed off, onto the camera.