Mars 10th of October

[NenoVento]

Hi All,

Here you have my try on the subject. Despite taking the image at sea level without an ADC, I'm quite happy about how it came out. Now I'm trying to identify what can be seen by using maps I've found in the Internet, but I'm rather confused. Syrtys Major is quite evident, as well as Mare Cimmerium, but is it  Olympus Mons the blob that you can see at Tharsis?. If you know of a proper map I can look at, please do let me know :-).

The gear:

Celestron CPC 800 GPS XLT
GSO 1.25" 2.5x Apochromatic Barlow Lens
Risingcam GPCMOS01200KPC

The software:

ToupSky (4 minutes, 11 gain and 0.45 ms, which allowed to get up to 114 FPS)
Autostakkert (30%, drizzle 1.5)
RegiStax
winJUPOS (for De-rotation and compensation of field rotation in altitude)
Fitswork 
The Gimp

Thanks for looking,

 

NV

Edited October 10, 2020 by NenoVento
Typos various and also added the winJUPOS reference

[paul mc c]

http://www.nightskies.net/mars/mars.html#

[Tommohawk]

That's a very nice Mars!

Couple of thoughts. I'm not keen on oversaturated images, but the colour seems a bit muted. Also, there have been some interesting posts recently about the best exposure time for Mars and planets generally. I've always gone for the fastest possible exposure to "freeze the seeing" but the consensus seemed to be that too short an exposure doesn't give optimum results. Folks were talking in the 5-15ms range if I remember rightly.

0.45 seems very short, though your image does look good. I used Toupsky last night for Mars and had to use incredibly low gain to give adequate exposure time. With my camera I have gain settings up to 50 and I was set to between 3-5. That gave exposure times of 8-10 ms. Not saying that's best for me or you though!

Either way, you shouldnt have to reduce the exposure to 0.45 just to get a good frame rate. 5ms should give 200FPS if your system is up to it (ie using ROI, USB3 etc) and if the system isnt up to it reducing the exposure wont help. Does that make sense?

BTW like you I also struggle with identification of features!

[NenoVento]

21 hours ago, Tommohawk said:

That's a very nice Mars!

Couple of thoughts. I'm not keen on oversaturated images, but the colour seems a bit muted. Also, there have been some interesting posts recently about the best exposure time for Mars and planets generally. I've always gone for the fastest possible exposure to "freeze the seeing" but the consensus seemed to be that too short an exposure doesn't give optimum results. Folks were talking in the 5-15ms range if I remember rightly.

0.45 seems very short, though your image does look good. I used Toupsky last night for Mars and had to use incredibly low gain to give adequate exposure time. With my camera I have gain settings up to 50 and I was set to between 3-5. That gave exposure times of 8-10 ms. Not saying that's best for me or you though!

Either way, you shouldnt have to reduce the exposure to 0.45 just to get a good frame rate. 5ms should give 200FPS if your system is up to it (ie using ROI, USB3 etc) and if the system isnt up to it reducing the exposure wont help. Does that make sense?

BTW like you I also struggle with identification of features!

Hi @Tommohawk,

Thanks for your inputs!. 

About the colour, I just let Registax to automatically balance the colours. Yes, I agree that the result looks a bit muted.

About the exposure time, I tough the same as you did, the shorter the better (with a nice histogram and as a little a ROI as possible, that is) . I'll have to look into this 5-15 ms range because cranking up the gain brings too much noise to the sign.

200 FPS is a dream with my gear (an USB 2 cammera and a 10+ year old laptop) but, well, I've got to fiddle with what I have ;-).

About Marps maps, the resource pointed out by @paul mc c is just what I was looking for, do take a look at it.

Regards,

NV

[NenoVento]

I've processed another video with the same setup. Here you have the result, beside an image from Mars Mapper (copying @chiltonstar's way of presenting)

The blob I was referring above was Cerberus :-). I believe I did get an image of Olympus earlier that night, but I had way too much gain in my setup (and probably the seeing wasn't so good either) so it didn't come out too nice:

Thanks for looking,

NV

Edited October 11, 2020 by NenoVento
Delete an unintended smiley

[Tommohawk]

On 10/10/2020 at 10:36, paul mc c said:

http://www.nightskies.net/mars/mars.html#

Thanks - that's very useful, hadn't seen it before.