Author Topic: ARRIVALS (The Newbie's Thread)  (Read 80984 times)

Thomas J

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Re: ARRIVALS (The Newbie's Thread)
« Reply #15 on: July 20, 2010, 07:25:59 am »
I got a few shots into crater survey and I found something I'm not sure of.

How would you classify the large dark area taking up most of the left side of the shot?



I saved it as a favorite after marking the large dark area as an interesting "other" feature. I looked at in Google Moon but could not find the area easily so I gave up.
Hi Boom929, welcome to the forum.That's a neat looking shadow, probably from a mound as Geoff has pointed out. Because it's a shadow it may not show up in other shots when the sun is at a different angle.

I hope you're enjoying the project.

Let us know each time you find something interesting.

Thomas  :)

stb76

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Re: ARRIVALS (The Newbie's Thread)
« Reply #16 on: July 22, 2010, 06:53:15 pm »
Hello,
I've been searching for about half an hour, but i couldn't find more information about the zoomfactor. The only thing I know is that I can look again at my recent assessed fotos in My Moon Zoo. There I can switch between three zoom levels. But how do I know the zoom level  in Crater Survey or Boulder Wars?
Thanks in advace!

Stephan

Geoff

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Re: ARRIVALS (The Newbie's Thread)
« Reply #17 on: July 22, 2010, 07:10:41 pm »
Hi Stephan and welcome to Moon Zoo.

The zoom level is not available when you are in the Crater Survey or Boulder Wars. I think this is to prevent bias during the selection process. You can always find out the zoom level afterwards by using the Recents/Favourites feature (as you've found out).

Hope you enjoy your time in the Zoo!


Thomas J

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Re: ARRIVALS (The Newbie's Thread)
« Reply #18 on: July 22, 2010, 08:22:02 pm »
Hi Stephan, yes there are three levels of zoom for these images. A great majority are close, a smaller amount are medium and then an even smaller number zoomed out far.
You will start to get used to which zoom level you are seeing, but as Geoff said, there is no feature to control zoom when classifying.

Happy hunting.

Thomas

stb76

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Re: ARRIVALS (The Newbie's Thread)
« Reply #19 on: July 22, 2010, 09:57:34 pm »
Hi,
before I leave off for today. I like to report something that I have learned new today.
It seems that a crucial point to identify craters is the sun angle.

# ID: AMZ10007sp
# Latitude: 20.9994°
# Longitude: 10.1572°
# Sun Angle: -85.72°
in this picture the sun is very low above the horizon (only 4°)



# ID: AMZ20005cn
# Latitude: -4.01281°
# Longitude: 342.452°
# Sun Angle: -52.88°
in this picture the sun is about 37° above the moon horizon.

I find find it puzzling that this altitude which seems not to be very high is high enough to fade out all shadows which help to identify craters.

Good night from Germany!
Stephan

Thomas J

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Re: ARRIVALS (The Newbie's Thread)
« Reply #20 on: July 23, 2010, 12:10:39 pm »
Hi Stephan, yes the sun angle is important as it reveals the shape and depth of the craters. The direction of sunlight is also important as it helps to work out whether, or not, you are looking at a crater as sometimes the features may be raised, like a mound or similar. As you have pointed out, when the sun is at a high angle the surface seems quite flat due to the lack of shadows. This is similar to visually observing the Moon with a telescope. When viewing a full Moon it's difficult to get any sense of depth, but point your equipment along the terminator of a half Moon and the shadows reveal all manner of interesting features.

Take a look at DJ_59's black and white thread for some beautiful contrasts.

Here http://forum.moonzoo.org/index.php?topic=214.0;topicseen

Thomas

stb76

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Re: ARRIVALS (The Newbie's Thread)
« Reply #21 on: July 23, 2010, 01:39:00 pm »
Thank you Thomas,

but I stilll wonder why there is such a lack of contrast at a sun level about -52° (which is in my opinion rather low).
Does it have to deal with the low albedo of the moon surface? In a lecture about moon photography I learned that the reflections grade of the moon surface depends very strongly on the angle of the sun and the angle of view. By that I understand that e.g. a crater with a slope angle 30° should have at the board surface in direction to sun an angle of incidence about 7° and at the board surface opposite to the sun an angle of incidence about 67°. The view angle (angle of reflection) would be in both cases 60°. Hence I would expect a big contrast between those two boards. Where is the mistake in my thinking?  ??? Or is the moon reflection a very very diffuse reflection.  :-\

Thanks for replys!
Stephan

P.S.: With the incidence and reflectioin angle I mean the grazing angle.
P.S.2: I hope "board" is the correct word for the slopes around the center of the crater.


Ian_Ferguson

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Re: ARRIVALS (The Newbie's Thread)
« Reply #22 on: July 24, 2010, 02:34:45 am »


 
AMZ1001909



Information
ID: AMZ1001909
Latitude: 1.12952°
Longitude: 23.3754°
Sun Angle: -84.81°
Scale: 1.27 meters / pixel
I've been marking the whole image with Speciel feature Fresh white is this any use?

Thomas J

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Re: ARRIVALS (The Newbie's Thread)
« Reply #23 on: July 24, 2010, 08:34:26 am »
Hi Ian, welcome to the Forum.
This image is zoomed out quite far and, therefore, it is hard to a great amount of deatail. I can see two, or possibly three, craters that exhibit a ray-like pattern.
Better, I think, to keep the classifications minimal in images like this.

I hope you are enjoying the project.

Thomas

jules

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Re: ARRIVALS (The Newbie's Thread)
« Reply #24 on: July 24, 2010, 01:44:56 pm »
Hi Ian - welcome to Moon Zoo! :)
I'd agree with Thomas on this one. I see 3 fresh whites in your image and we have had confirmation from the Moon Zoo team that they would like us to mark all fresh whites even those that are smaller than the crater marking tool so rather than mark the whole image they would prefer we marked individual white craters.

Ian_Ferguson

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Re: ARRIVALS (The Newbie's Thread)
« Reply #25 on: July 25, 2010, 01:40:44 am »
Thanks Jules and Thomas I'll be more discriminating in future

Luke7580

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Re: ARRIVALS (The Newbie's Thread)
« Reply #26 on: August 10, 2010, 02:04:43 pm »
Hello Tom, Finally found you! Is this the "newbie" page what you was talking about? PS... im sending this from work, when my pc gets back from the menders I can be a bit more pro-active..... Speak soon Tom.

Thomas J

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Re: ARRIVALS (The Newbie's Thread)
« Reply #27 on: August 10, 2010, 08:47:15 pm »
Welcome aboard, Luke  ;D

Yes, this is the thread, glad you founds us. Look forward to catching up with you as soon as your pc is fix.

All the best.  :)

jules

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Re: ARRIVALS (The Newbie's Thread)
« Reply #28 on: August 10, 2010, 11:23:08 pm »
Hello Tom, Finally found you! Is this the "newbie" page what you was talking about? PS... im sending this from work, when my pc gets back from the menders I can be a bit more pro-active..... Speak soon Tom.

Welcome to Moon Zoo Luke! Glad you found us. ;) Hope the PC recovers soon.

aspringer

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Re: ARRIVALS (The Newbie's Thread)
« Reply #29 on: August 18, 2010, 05:04:04 pm »
Hello
I am sure I simply haven't looked in the right area, but where can I find a tutorial for" My Moon Zoo". I see the astronauts holding numbered signs (golf holes?) why are there so many blue lollipops? What do the numbered signs mean.

I am sorry to be asking what has probably already been asked and answered. Thank You in advance for your help.