Here's an image from this morning, in poor seeing but still some good details thanks to the larger size now that it's close to opposition :-)
This image is 2 minutes in each of IR742 , G , B, stacked the best 2000 frames from each channel. Due to the seeing some extreme processing was required, and so the polar cap is over-exposed :-( Not a lot I can do about that...
Hi Bird, good job, the IR certainly helps with the resolution for a colour image when the seeing is poor, although I think I prefer the colour from R, G & B.
You have some nice detail from the IR, the "V" shape just north of Oxia Palus is well defined. Well done as usual.
Wow! ... I agree with Darren, stunning image! My mate was imaging Mars through his 15" Obsession the other night with a ToUCam and it looked NOTHING like this!
Thanks for the comments... if I ever get some good seeing on Mars (not likely around here in Summer!) then I'll try a proper RGB, but until then it's going to be IR-G-B all the way :-)
Mars brings back good memories - that's where I started imaging in 2003 with a ToUCam. The big difference in brightess in colour channels certainly gives an advantage to mono camera + filters where you can set the gain and exposure separately for each channel.
Hi Anthony - great to see another planetary image from you - it is a super shot - you have captured heaps of detail - thanks for sharing.
Any more sessions soon?
I posted this over at Cloudy Nights, but its certainly worth repeating here. Its really a great pic. The best I've seen this season that shows the "life saver" effect on the NPC. I split Bird's jpg in to RGB, and it shows up very, very well in the Red channel, as to be expected. A great catch and important pic from this apparition.
We keep trying to offer the other side of Mars to complement your excellent shots such as this one. Life is hard as you know at 14 arc seconds. We are still newbies with our new Dragonfly2 camera and have an opinion about the camera that I'd like you to comment on. Specifically about life in the 12bit world. When you have a very bright planet like Mars then it is relatively easy to photograph Mars at 60 fps which will preserve nearly all the 256 levels of grey in the final image which makes stretching unnecessary. . When we switch to 30 fps at 12 bit, we don't notice a big difference in the final RGB image which is not surprising considering the monitor can only show 256 levels of grey. Such is not the case with Saturn which is dim and the dark frames do not stretch as smoothly as the 12 bit frames. Do you agree with this assessment?
And finally, we have been uploading our pictures to Japan's ALPO. But we rarely see any of the excellent photos from the Australians on that site? Is there a reason for this? I told my wife Gail that there are probably less than 50 astronomers around the world capturing images of Mars on any particular night. And ALPO only seems to get a few of them.
I noticed that the temps this coming Friday in Canberra will drop 20 degrees C over the night. This compares to a 7 degree drop in Miami. Is your telescope capable of staying in equilibrium throughout the night without any active assistance? Does Mars require refocusing from the contraction of the tube?
We keep trying to offer the other side of Mars to complement your excellent shots such as this one. Life is hard as you know at 14 arc seconds. We are still newbies with our new Dragonfly2 camera and have an opinion about the camera that I'd like you to comment on. Specifically about life in the 12bit world. When you have a very bright planet like Mars then it is relatively easy to photograph Mars at 60 fps which will preserve nearly all the 256 levels of grey in the final image which makes stretching unnecessary. . When we switch to 30 fps at 12 bit, we don't notice a big difference in the final RGB image which is not surprising considering the monitor can only show 256 levels of grey. Such is not the case with Saturn which is dim and the dark frames do not stretch as smoothly as the 12 bit frames. Do you agree with this assessment?
And finally, we have been uploading our pictures to Japan's ALPO. But we rarely see any of the excellent photos from the Australians on that site? Is there a reason for this? I told my wife Gail that there are probably less than 50 astronomers around the world capturing images of Mars on any particular night. And ALPO only seems to get a few of them.
DB
G'Day DB... I do contribute to ALPO but mostly in the Jupiter section. I figured that most of the mars images would come from the north this time around... but I guess the weather up there has not been good.
I'm away at the moment, but I'll be home from the end of the month so I can start imaging again just after opposition.
I always use the 16 mode of the camera, 12 bits of data as you say. Mostly because I use a fast framerate of 50fps and on most things this only gives a partial histogram and so the extra few bits of data resolution help to avoid the low-data effect that everyone calls onion-rings
On Mars I could use a higher fps for the red channel since its so bright, but with the poor seeing around here I almost always end up using 742nm IR for the red channel instead :-)
ps you should use the format-7 mode of the camera that lets you choose any fps you want, rather than just the standard 60/30/15 etc.
Heya DP, them was good times... I hope to get back to SV this year, I havent made it the last 2 years....
Doodles... I missed your question re: temp drops, and yes they are a major problem where I live. I've fitted a peltier-based cold air system behind the primary that turns the inside of the scope into a fridge, but even so with my current mirror (14.5" conical) it's too thick to cool rapidly.
I have a 16" composite mirror coming along soon that will cool much much better, so I'm looking forward to that :-)
Here's an image from this morning, in poor seeing but still some good details thanks to the larger size now that it's close to opposition :-)
This image is 2 minutes in each of IR742 , G , B, stacked the best 2000 frames from each channel. Due to the seeing some extreme processing was required, and so the polar cap is over-exposed :-( Not a lot I can do about that...
cheers, Bird
I just spilt my coffee top gun style.
This has to be one of the finest mars images Ive seen. Just stunning.
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