Martian Photo

[PSALM19.1 (Shaun)]

OK, so was looking on BBC Sky at Night website and saw a photo of Mars (below) taken by a 10 year old girl with a Celestron C8...got me wondering: is it the camera that makes the image so large and detailed? I mean, when I look at Mars with my Dob which is the same aperture, I certainly don't see anything like that image (well, I CAN see similar details but not at the magnification that photo has!) Anyone explain?

[rustigsmed (Russell)]

hi shaun,

when it comes to mars it is all about timing and seeing. forget seeing anything if its not near opposition. speaking of which 2018 is the best martian opposition for the next 15 years or so. so you've got time to prepare for that.

here is my best from last year's opposition https://www.flickr.com/photos/803366...ream/lightbox/
not as good as the 10 year old - so i'll blame the seeing

cheers

rusty


http://www.iceinspace.com.au/planetopp.html

[SkyWatch (Dean)]

Hi Shaun,
The Mars image has probably been processed by stacking dozens of very short exposure individual images, using Registax or similar, to reduce noise, increase apparent resolution and cancel out times of poor seeing, etc. The image can then be enlarged way beyond what you would see in your scope. Also, as Rusty notes, it is best to look at Mars when it is nearest the Earth (every 2 years or so), so that its apparent diameter is largest. That way you can see more detail, assuming you have a good scope, it is properly collimated and is at ambient temperature, the seeing is good, you are using the best magnification for the conditions and scope, you train your eye to pick out details (this requires time and practice), etc.
Our poor eyes can't really compete with dozens (or hundreds) of stacked images, even though our brain does a pretty good job of "auto-stacking". However, if you were to take just one image and compare it with what you can see by eye, you will probably find the eye wins out!

Happy Mars viewing in 2018!

- Dean

(PS: Your images are still pretty good Rusty!)

[raymo]

The C-8 is the same aperture as your Dob, but assuming that your Dob
has a focal length of around 1000mm [f/5], and assuming that the C-8
was used without a focal reducer, the C-8's 2030mm [f/10] focal length will produce an image twice the size. As the image is twice the size to
start with, it can also be cropped more to produce a larger good quality
image.
raymo

[barx1963 (Malcolm)]

The other thing to think about is how big is the sensor in the camera that was used. Even on my DMK camera, the sensor is only 12mm or 1/2" wide, and for a planetary camera, that is fairly large, 1/4" is common as well. So that image as it came out of the scope may only be 12mm wide, not the size you see it on the screen.

Malcolm

[mental4astro (Alexander)]

Shaun, do you have a link to that article? I don't doubt a 10year old took it, but the implication is somewhat dismissive of the whole thing. 'Really, a ten year old took that!? Must be pee easy that astronomy caper to use happy snappy photos...'.

That is one heck of a photo, and I am suspicious of the background to it. Like Dean, I suspect that the image is a processed on, and not a happy snappy. If a ten year old used a C8 with a half decent camera and post processing, I'd believe that more the case.

there are clouds visible in that image (the whispy white stains to the left and right. A happysnappy I really, really doubt would show that. By happy snappy I mean a phone camera pointed into the eyepiece.

I have seen details like this in my C8. Very much dependent on good seeing as Dean also mentions. I haven't seen detail like this in my dobs, but only because I don't use them for the Mars. But such detail will be there if conditions allow. It's one of my most cherished experiences to be able to tease out such fleeting details from Mars. A quiet, heart stopping moment for me.

Alex.

[PSALM19.1 (Shaun)]

Yes mate, here it is: (just says she "had a camera attached" - which I guess could mean anything!)

http://www.standard.co.uk/news/olivi...w-9747880.html

[mental4astro (Alexander)]

Thanks for the link Shaun.

Well, if she took it, it doesn't matter if it was her dad's gear, it's hers and we should applaud her interest in astronomy Shame that it is actually the journalist or the editor that chose vague words. All power to our sister!

[Visionary (David)]

Mmmmm......... does Dad work in imaging, or image processing?

[julianh72 (Julian)]

Originally Posted by PSALM19.1

Yes mate, here it is: (just says she "had a camera attached" - which I guess could mean anything!)

http://www.standard.co.uk/news/olivi...w-9747880.html

Interesting to note that the telescope she is shown standing next to (looks like a 90 mm or so refractor on a Celestron SLT mount?) ISN'T the one that took the photo (Celestron C8 200 mm CST)!

[PSALM19.1 (Shaun)]

Yes, noticed the smaller scope too...maybe it's her "spotting" scope...hehehe