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Delboy_Hog

Mak 127 - Mars 24th March. DMK21 vs SPC900 – what’s the white splodge?

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Hi folks,

I captured a few shots of Mars and Saturn in the early hours of Monday morning.  Unfortunately the Saturn images were waaaay too dark and dim to be useable.  Even though they looked bright enough on my laptop screen when I play the avis back now, I realise I needed to bump up the settings significantly before I’d be able to create an image recognisable as Saturn!  :BangHead: 

So anyway, boosted by my attempt earlier in the month with the 2x barlow, I thought I’d have a crack with the 3x.  Truthfully I was pushing my luck as the seeing was pretty poor, and very few frames actually captured the round disk of Mars.  I believe this explains the ‘mist’ of noise around the planet in the images from both cameras!

When I ran the DMK21 version through Registax, I noticed a white splodge on the upper right section of the planet itself.  Bit frustrating I thought, but then there’s streetlamps everywhere here and I’m using a £9.99 3x barlow of no known brand, so these things happen.  But when I processed the SPC900 version taken about 10 minutes later, it cropped up again, and appeared to have moved a distance relative to the other features on the images, in line with Mars’ rotation.  Any ideas? 

post-23024-0-56714100-1396036886.png post-23024-0-89716300-1396036907.png

In comparing the cameras, I think these confirm the suspicions I’d formed from the Jupiter images I'd managed earlier in the year, that this camera is very strong in good seeing conditions, and picks up a lot more detail in good seeing than the SPC900 does.  However, in poor – average seeing, the SPC900 actually does just as good a job really.  I guess ultimately any equipment we have is going to be limited by the atmosphere we have to look through...

Can't wait to have another crack at these two fascinating targets, hopefully in better seeing, and when I get my settings right! :rolleyes: 

post-23024-0-68892000-1396037267_thumb.p post-23024-0-15245600-1396037322_thumb.p

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The white splodge is quite possibly some sort of cloud pattern.

James

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And they're good efforts at imaging the two planets, too :)

James

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Color images suffer from dispersion. You could try derotated lrgb in Winjupos.

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Hi Derek,  excellent efforts. The white splodge is cloud covering Elysium Mons - one of the Martian volcanoes! You have imaged later than my effort which was shortly after midnight and I captured the same. Syrtis Major - which is the dark  "V" shape coming from the left was just approaching the limb when I was imaging. Your later capture shows it further on its travels and it is much more prominent. The bright area at the bottom of your images is Hellas Chaos with the North Polar cap being directly opposite at the top of your image. Well done!

                                                    Best regards,

                                                                           Ralph

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And they're good efforts at imaging the two planets, too :)

Thanks James, I was hoping it was some kind of cloud formation, once I'd seen it on both images, but really wasn't sure.  I'm getting there, improving each time which is pleasing, just desperate to have a night over the next few weeks where the conditions are reasonable at least.  :rolleyes:  

Color images suffer from dispersion. You could try derotated lrgb in Winjupos.

You're right, I do need to get the hang of Winjupos!  The derotation sounds like a really handy tool so I might download it this week and see if I can have a play with it!

Hi Derek,  excellent efforts. The white splodge is cloud covering Elysium Mons - one of the Martian volcanoes! You have imaged later than my effort which was shortly after midnight and I captured the same. Syrtis Major - which is the dark  "V" shape coming from the left was just approaching the limb when I was imaging. Your later capture shows it further on its travels and it is much more prominent. The bright area at the bottom of your images is Hellas Chaos with the North Polar cap being directly opposite at the top of your image. Well done!

                                                    Best regards,

                                                                           Ralph

Many thanks Ralph, I've just taken a look at your pics.  The Jupiter you got on the evening before was lovely, you got detail in Ganymede! :shocked: Fantastic!  It's really interesting to see our shots taken at different times to get an impression of how Mars rotates.  I still don't know as much about the features of Mars as I'd like to, so I'm grateful for your description, thank you! :icon_salut:

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From the bright background of the SPC900 Saturn shot, I'm guessing you had the settings as 'high' as they'll go?  I've had the same thing when pushing the settings on the planets, the background turns blue. :rolleyes:   The dark background of the DMK shot suggests you might be able to get more out of it though?

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From the bright background of the SPC900 Saturn shot, I'm guessing you had the settings as 'high' as they'll go?  I've had the same thing when pushing the settings on the planets, the background turns blue. :rolleyes:   The dark background of the DMK shot suggests you might be able to get more out of it though?

Yes that's right, exposure, gain (and brightness too I think) were all at maximum, which doesn't usually end well!  I think the low altitude of Saturn, the nearby streetlamps and the quality of my 3x barlow means that's pretty much always going to happen unfortunately. 

You're right about the other camera too, there's plenty more to come from the DMK21.  The settings can go significantly higher to enable a brighter image (hopefully without introducing too much noise), so I'll certainly be giving that a go next time out!

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Thanks Richard!  I just wish the detail was a little more 'crisp' and less fuzzy! :grin: Hopefully some better seeing will help with that!

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