Excellent seeing in Brisbane last night. Had finished work and gave Saturn another shot. Attached is an original capture size stack, a downsampled one, and an RGB study of the planet, the capture method (one thumb required for tracking), and the camera, and a closeup of an attempt to enhance the hexagon, and a spherical projection of the pole simulating an overhead view.
Canon EOS 600D, 5x Powermate, teleconverters, 12" SkyWatcher Goto Dobsonian, manually tracked, 2.5 minutes video crop mode.
Fantastic images Tom. I'm spellbound by what you are achieving with this setup but rather confused as to the "manual tracking"? How can you keep Saturn on chip without the scope's tracking activated?
Hi Stuart, for this I don't activate the telescope's auto tracking. The scope is unaligned and only moved by using the hand controller. I started the switch to manual tracking as it was sometimes easier than correcting any auto tracking errors during capture (which introduces a little backlash as well as a lag before the auto tracking kicks in again). Call me lazy but it's easier for me to point and manually track than it is to go through the alignment process
Hi Stuart, for this I don't activate the telescope's auto tracking. The scope is unaligned and only moved by using the hand controller. I started the switch to manual tracking as it was sometimes easier than correcting any auto tracking errors during capture (which introduces a little backlash as well as a lag before the auto tracking kicks in again). Call me lazy but it's easier for me to point and manually track than it is to go through the alignment process
Cheets,
Tom
I never thought this was possible Tom with the slew speeds being too fast when out of tracking mode but clearly you are making it work. I see Eric does the same on lunar. As you say backlash and lag can be annoying when tracking.....hmmmm...might just try your method.
Blimey Tom – you should have posted a “Warning” about image scale as the 1st Saturn almost knocked me off my chair with its sheer size when I opened the image!
Great to see the photos and read the description of your set up too.
Pretty AWEEESOME Tom.
I have been guiding my solar stuff for the last week (see Heart of the Sun Beats post) and I got the idea from your description of your capture process a couple of weeks ago.
I still cant get a go for the weather at night is rain,rain,rain.
Great work Tom! In my experience auto guiding sucks for your reasons stated. You are still obviously polar aligned though right? & just manually with the controller, correct..?
Stuart, as the planet approaches the field of view I set the slew speed to 1x (out of the 9 speeds available) to then match the movement. This works pretty well until the object gets close to zenith when the azimuth at that speed can't keep up.
John, nothing is aligned, it's just the manual alt/az movements through the hand controller. I've gotten pretty used to hitting those buttons in the right sequence (up, left left, up left left up left up left left etc) depending on the position of the object in the sky.
With all this talk of manual input, the autotracking on the dob is quite good when you go through the alignment process. It's just at the magnifications I use that I prefer manual.
Tom I must agree with Trevor you really are setting a precedent here and with gear that is accessible and versatile. Apart from perhaps the scope every family needs a good DSLR.Your pics just keep getting better.
