Mars 5 May 2018 - hints of polar cloud?

[Sebbie]

Hi everyone,

Waited for Mars last night and was rewarded with a brief window of steady seeing before morning fog rolled in. Just finished processing recorded SERs and noticed something strange on the planet night side past terminator.. originally thought it may be a stacking artefact but the feature is clearly visible on multiple images and tends to rotate with the planet (animations attached). A high polar cloud perhaps?

WinJUPOS derotated image shows another bright SPC region which is associated with a leading perpendicular streak. Quite a lot of detail throughout the disk, not yet 12 arc seconds in size.

Thanks for checking these out, curious what people think.

Cheers,
Seb

[Stefan Buda]

Hi Seb,

Good work. Martian terminator projections have been reported for over a hundred years, and there are ccd images from the last few oppositions that prove their reality. The most common explanation is high altitude cloud or mist.

[Troy]

Well done Seb :thumbsup:

[E23]

Hi Seb

What magnificent images.

I'm not into much astro-imaging but I can tell it's very high quality work.

I just happened to be test running a ZWO ASI120mc camera on an Orion 102mm ED reflector and I was out there the last couple of nights doing what you did, Jupiter and Mars. My forte is asteroid astrometry so really I'm a beginner at 'pretty pictures' as you can tell from my 1st attempts with this kit. My past attempts at the planets were not much better. (see 'gallery' on my new website http://www.arcadiaobservatory.org ) Those were using a C14.

Maybe you can offer some help with this:
Orion 102mm ED + Tele Vue 3x Barlow (2100mm fl, F21), ZWO ASI120mc camera. The images below were taken: 200 frames, 12ms exposure about 60 fps. Processed in Registax 6. No idea how to tweak the wavelet functions but tried a lot of combination. My camera has about the same specs. as yours. The seeing was good on the 6th in Sydney, not so good last night. I'm doing something very bad.

Is it my lack of experience with Registrax? Is there a good guide for the whole process. Do I need to play with Photoshop as well? Is the image scale on the chip not large enough. Mars is a lot worse the Jupiter but still about 31 pixels wide.

Help anyone with my embarrassing images?

Andras

[Camelopardalis]

Great images Sebbie :thumbsup: good catch with the cloud/mystery!

Could use a touch less green IMO, I find the 224 is a little green heavy.

[Sebbie]

Stefan, thanks for expert reassurance. Hope that follow up observers will be able to record this cloud and track its evolution.

Troy and Dunk, thanks for kind words. Dunk, I followed your advice cutting down on green channel. Updated images are showing bright SPC area more prominently now.. it's been identified by Damian Peach as Argenteus Mons, a regular outlier in the early southern spring. I agree that colour ASI is very green heavy on raw captures, and very challenging to get an accurate colour reproduction. In a way I wish the DFK had comparable resolution and sensitivity.. I'd choose to use it instead.

Thanks Andras. At first I'd try to increase image scale of your videos, Jupiter does look rather small. I use AutoStakkert!2 for stacking and Registax exclusively for RGB alignment-balance-contrast-wavelet sharpening. The former produces better stacks and has a very good drizzle function for undersampled recordings (increasing size of the final image). RGB steps are important following debayering. Links to some online guides below, hope you find them helpful.

Cheers,
Seb

https://www.autostakkert.com/wp/guides/
https://www.cloudynights.com/topic/562976-autostakkert-alignment-points-question/
http://www.awesomeastronomy.com/tutorials/planetary-imaging/60-a-step-by-step-guide-to-processing-planetary-images

[E23]

Thanks for that Seb, I'll go do some reading.
Andras

[Camelopardalis]

Yeah totally agree, the colour balance is one of the challenges :thumbsup:

Nice improvement in the SPC though!