IPB

Welcome Guest ( Log In | Register )

4 Pages V  < 1 2 3 4 >  
Reply to this topicStart new topic
MOM: Initial Mars operations, News and Mars photos after orbit insertion
Krit
post Sep 29 2014, 01:06 PM
Post #16


Newbie
*

Group: Members
Posts: 3
Joined: 30-January 14
Member No.: 7116



Another photo (from the ISRO Facebook Page)

"Regional dust storm activities over northern hemisphere of Mars - captured by Mars Color Camera on-board ISRO's Mars Orbiter Mission.
The image was taken from an altitude of 74500 km from the surface of Mars."


Attached thumbnail(s)
Attached Image
 
Go to the top of the page
 
+Quote Post
vikingmars
post Sep 30 2014, 08:03 AM
Post #17


Member
***

Group: Members
Posts: 822
Joined: 19-February 05
From: Close to Meudon Observatory in France
Member No.: 172



My interpretation, processed, de-noised and de-saturated...
Looks like the Red Planet people dreamed on in the 50's !
And CONGRATULATIONS again to India ! Enjoy... smile.gif
Attached Image
Go to the top of the page
 
+Quote Post
Julius
post Sep 30 2014, 12:06 PM
Post #18


Member
***

Group: Members
Posts: 306
Joined: 13-April 06
From: Malta
Member No.: 741



I'm no expert in image processing but I would think this version of red colour seems more real cos I don't believe the dust clouds to the upper left would be that white as depicted in Ted 's version.
Go to the top of the page
 
+Quote Post
vikingmars
post Sep 30 2014, 12:34 PM
Post #19


Member
***

Group: Members
Posts: 822
Joined: 19-February 05
From: Close to Meudon Observatory in France
Member No.: 172



Thanks Julius. But what is the "Ted's version", you are referring to, please ?
Go to the top of the page
 
+Quote Post
Krit
post Sep 30 2014, 12:53 PM
Post #20


Newbie
*

Group: Members
Posts: 3
Joined: 30-January 14
Member No.: 7116



I suppose he is referring to this version.
Go to the top of the page
 
+Quote Post
djellison
post Sep 30 2014, 01:28 PM
Post #21


Administrator
****

Group: Chairman
Posts: 14022
Joined: 8-February 04
Member No.: 1



QUOTE (Julius @ Sep 30 2014, 04:06 AM) *
I'm no expert in image processing but I would think this version of red colour seems more real cos I don't believe the dust clouds to the upper left would be that white as depicted in Ted 's version.


Check out imagery from Hubble, or the Rosetta OSIRIS flyby imagery - white clouds are the norm. MEX has seen white fog, MGS MOC/WA saw white clouds. The MRO MARCI weather updates regularly show a sluice of white clouds around Mars.

Even amateur ground based astronomers have seen white clouds on Mars. I've seen them thru a tiny telescope with my own eyes.

Go to the top of the page
 
+Quote Post
Julius
post Sep 30 2014, 03:45 PM
Post #22


Member
***

Group: Members
Posts: 306
Joined: 13-April 06
From: Malta
Member No.: 741



What about dust clouds resulting from a dust storm? Are they white in colour?
Go to the top of the page
 
+Quote Post
djellison
post Sep 30 2014, 03:58 PM
Post #23


Administrator
****

Group: Chairman
Posts: 14022
Joined: 8-February 04
Member No.: 1



Obviously not - which is why the dust storms visible in every version of this I've seen retain their ochre / butterscotch color.
Go to the top of the page
 
+Quote Post
elakdawalla
post Sep 30 2014, 04:06 PM
Post #24


Administrator
****

Group: Admin
Posts: 5052
Joined: 4-August 05
From: Pasadena, CA, USA, Earth
Member No.: 454



It's been interesting to see all the different takes on this photo. People seem to agree that the original was too red and saturated, but the corrections have been varied. Here's a roundup of links to processed versions I've seen -- have I missed any?
Original
Ted Stryk
Olivier de Goursac
Judy Schmidt
Fred Calef - with place names
Elisabetta Bonora & Marco Faccin


--------------------
My blog - @elakdawalla on Twitter - Please support unmannedspaceflight.com by donating here.
Go to the top of the page
 
+Quote Post
Bjorn Jonsson
post Oct 1 2014, 12:51 AM
Post #25


IMG to PNG GOD
****

Group: Moderator
Posts: 1921
Joined: 19-February 04
From: Near fire and ice
Member No.: 38



Beautiful images so far and congratulations to the Indians. Clearly this mission is going to be the best source ever of global color views of Mars, maybe a bit like a 'super VMC'. Hopefully a 'PDS-like' version of the images will be released in the future to make more accurate processing of these images possible for us here.

The various versions of this image are interesting. Here is a quick-and-dirty version I did by reducing the color saturation a bit. I then corrected the color using Mars' global spectrum as a guide, together with what Mars has looked like to me through a telescope. Planetary color is highly subjective so I really don't know which one of the various versions posted here is the most realistic one. But I agree that the original image is probably too saturated and reddish and probably the blue channel should be brighter, at least in the dark areas (it's remarkably close to 0 in the darkest regions). Here is my version:

Attached Image


The terminator is a bit ugly at lower left. This is a processing artifact; I may do a better version later.


Go to the top of the page
 
+Quote Post
Bjorn Jonsson
post Oct 1 2014, 01:13 AM
Post #26


IMG to PNG GOD
****

Group: Moderator
Posts: 1921
Joined: 19-February 04
From: Near fire and ice
Member No.: 38



QUOTE (elakdawalla @ Sep 30 2014, 04:06 PM) *
Here's a roundup of links to processed versions I've seen -- have I missed any?

I also found versions by Don Davis and Mattias Malmer on Facebook.
Go to the top of the page
 
+Quote Post
mcaplinger
post Oct 1 2014, 02:43 AM
Post #27


Senior Member
****

Group: Members
Posts: 1614
Joined: 13-September 05
Member No.: 497



QUOTE (Bjorn Jonsson @ Sep 30 2014, 05:51 PM) *
Hopefully a 'PDS-like' version of the images will be released in the future to make more accurate processing of these images possible for us here.

From http://www.hou.usra.edu/meetings/lpsc2014/pdf/2449.pdf "MARS COLOR CAMERA ONBOARD MARS ORBITER MISSION: SCIENTIFIC OBJECTIVES &
EARTH IMAGING RESULTS", A.S. Arya et al:
QUOTE
Data Product Schema : An MCC image is a Bayer filter mosaic, a color filter array (CFA) for arranging RGB color filters on a square grid of photo sensors. The demosaicing algorithm is employed to reconstruct a full color image. Level-1 product (calibrated data) generation involves detector wise photo response non-uniformity model correction as understood from pre launch laboratory calibration exercises; line/pixel loss correction and tagging the geographic coordinates to each pixel. Level-1, corrected are generated for users. The software
pipeline produces calibrated data to generate minimum Planetary Data System (PDS) compliance product.


--------------------
Disclaimer: This post is based on public information only. Any opinions are my own.
Go to the top of the page
 
+Quote Post
vikingmars
post Oct 1 2014, 07:38 AM
Post #28


Member
***

Group: Members
Posts: 822
Joined: 19-February 05
From: Close to Meudon Observatory in France
Member No.: 172



QUOTE (elakdawalla @ Sep 30 2014, 06:06 PM) *
It's been interesting to see all the different takes on this photo. People seem to agree that the original was too red and saturated, but the corrections have been varied.

Thanks Emily for this interesting compilation.
The somewhat "yellowish" (not pure white) color I found after my processings for the dust clouds on the northern hemisphere is consistent with MARCI team's Mars weather reports : "Regional storm activity picked up in the northern hemisphere, with large storms occurring from Utopia to Arcadia and arcuate-shaped storms following the Acidalia storm track into Chryse"... And in the southern hemisphere, ice crystal clouds appear white indeed. Also, Mars is not a "bright" planet. Thus, I believe my interpretation is a close representation to what the human eyes would see smile.gif
Go to the top of the page
 
+Quote Post
Julius
post Oct 2 2014, 09:20 PM
Post #29


Member
***

Group: Members
Posts: 306
Joined: 13-April 06
From: Malta
Member No.: 741



Only now I realize who vikingmars is! I have 'visions of mars' in my mars books collection..brilliant work!
Go to the top of the page
 
+Quote Post
wildespace
post Oct 6 2014, 07:22 AM
Post #30


Member
***

Group: Members
Posts: 188
Joined: 15-January 13
Member No.: 6842



A quick Photoshop levels adjustment, using "Enhance Per Channel Contrast" with "Snap Neutral Midtones" box checked:

Attached Image


I think this has resulted in colours very close to the colours of the surface as we have seen from raw Mastcam and MAHLI images.

I remember reading in a few places that the pronouncedly red appearance of Mars when photographed from outside of its atmoshere is due to all the dust suspended in its atmosphere.


--------------------
Go to the top of the page
 
+Quote Post

4 Pages V  < 1 2 3 4 >
Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 18th December 2017 - 12:58 PM
RULES AND GUIDELINES
Please read the Forum Rules and Guidelines before posting.

IMAGE COPYRIGHT
Images posted on UnmannedSpaceflight.com may be copyrighted. Do not reproduce without permission. Read here for further information on space images and copyright.

OPINIONS AND MODERATION
Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators.
SUPPORT THE FORUM
Unmannedspaceflight.com is a project of the Planetary Society and is funded by donations from visitors and members. Help keep this forum up and running by contributing here.