Page 1 of 2 12 LastLast
Results 1 to 15 of 16

Thread: Who's wrong? Lightwave Mathematics or NASA?

  1. #1
    luxowaver silviotoledo's Avatar
    Join Date
    Jun 2003
    Location
    Brazil
    Posts
    1,831

    Who's wrong? Lightwave Mathematics or NASA?

    Take a look at this NASA image

    https://www.nasa.gov/sites/default/f...se_frame_0.jpg

    I modeled the Earth and the Moon with the correct sizes and used Lightwave lens to try to simulate the image.

    Moon Radius 1.737 km
    Earth Radius 6.371 km
    Distance from Earth to the Moon 384.400 km

    The problem is that the Moon only start to appear as some small pixels on an HD resolution when lens is 4000 mm.
    Maybe the NASA picture is wrong ( fake )

    So how do we see the moon from earth with our eyes ( 50 mm lens ) ?

    Is the NASA/Astronomy distances incorrect or is Lightwave math incorrect?
    Silvio Toledo
    Brazil

  2. #2
    luxowaver silviotoledo's Avatar
    Join Date
    Jun 2003
    Location
    Brazil
    Posts
    1,831
    Click image for larger version. 

Name:	Conspiracao.jpg 
Views:	205 
Size:	322.6 KB 
ID:	137383
    Silvio Toledo
    Brazil

  3. #3
    Member
    Join Date
    Oct 2003
    Location
    Orlando, FL
    Posts
    4,156
    You do see that the NASA picture is one from the moon pointing at the earth? And your simulation is one from earth pointing to the moon?
    The earth will obviously be larger in the NASA pic than the moon is from the earth because it is a photograph of a larger object from a smaller object.
    And I wouldn't call the image "faked" but a zoom lens can seem to increase the scale of the earth (or moon) because it flattens the distance between objects and magnifies the foreground image. So you can trick the eye, like this

    But, yeah, I think your simulation has some kinks in it.

  4. #4
    The NASA image is also a render, so they could have used any zoom they wanted. Go outside, take a picture of the moon with your phone. tell me how big it looks in that image. (spoiler: very small)

  5. #5
    Male Modeler ccclarke's Avatar
    Join Date
    Mar 2006
    Location
    New England
    Posts
    134
    If you want to duplicate the (non-fake) NASA image, you also need to determine the focal length of the lens used to create the original picture.

    The diameters of and distances between both bodies are established facts.

    This follows the time-proven rule: Garbage in = Garbage out. Configure Lightwave properly and you will be successful.

    CCC

  6. #6
    Old Dog Learns New Tricks RudySchneider's Avatar
    Join Date
    Jan 2006
    Location
    Lincoln, CA
    Posts
    1,309
    I'm not completely sure I understand your issue, silviotoledo, but you got my curiosity up, so I decided to do a bit of simulation myself. The Earth has a mean diameter of 7917 Miles, the moon has a diameter of 2159 miles, and is 238,900 miles away. The Apollo 8 was in a circular orbit 60 miles above the surface of the moon. So, my Earth and Moon objects are 791mm and 216mm, respectively, and I've separated them by 23.89 meters. The 60 mile orbit means the "Camera" is parented to and at (216 + 12 (60 mile above moon means 120 miles added to diameter) =) 228mm above the center of the "Moon."

    Here's a 50mm focal length shot of "Earth" from "Moon's" orbit. I simply rotated the "Moon" until the "Earth" came into view.

    Fun exercise.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Earth_Moon.jpg 
Views:	101 
Size:	20.4 KB 
ID:	137386  
    Last edited by RudySchneider; 07-15-2017 at 11:46 PM.
    There are no problems, only opportunities...

  7. #7
    TrueArt Support
    Join Date
    Feb 2003
    Location
    Poland
    Posts
    8,067
    1737 km radius * 2 = 3474 km diameter of sphere/circle

    384400 km distance to the Moon * 2 * PI = 2415256 km full 360 degrees view.

    3474 km / 2415256 km = 0.0014379 = 0.144% of the full 360 degrees view.
    * 360 degrees = 0.517 of single degree.

  8. #8
    Goes bump in the night RebelHill's Avatar
    Join Date
    Nov 2003
    Location
    jersey
    Posts
    5,792
    yeah... sensei's right about the angular measurement... its easiest.

    If you measure the sky in degrees, the the horizon on one side to that on the other is (obviously enough) 180deg... the appearance of the moon is about 0.5 deg across... In LW, make a moon of correct size/scale, at corresponding distance, zoom your camera in till it has 0.5deg field of view... moon fills the frame.
    LSR Surface and Rendering Tuts.
    RHiggit Rigging and Animation Tools
    RHA Animation Tutorials
    RHR Rigging Tutorials
    RHN Nodal Tutorials
    YT Vids Tuts for all

  9. #9
    Registered User Slartibartfast's Avatar
    Join Date
    Jun 2012
    Location
    Sweden
    Posts
    420
    The appearent size of the moon is smaller than people think. When asked "how big is the moon compared to an object at arms length?" many people answers "like a tennisball". The fact is you can cover the moon with your little finger's nail. Which is about 0.5 degrees as previously mentioned ;-)

  10. #10
    Member
    Join Date
    Oct 2003
    Location
    Orlando, FL
    Posts
    4,156

  11. #11
    Registered User Slartibartfast's Avatar
    Join Date
    Jun 2012
    Location
    Sweden
    Posts
    420
    Lol!
    Here is a pic I took before It set in Arizona last year. Can you spot Mercury?
    Click image for larger version. 

Name:	IMG_1322.JPG 
Views:	128 
Size:	1.10 MB 
ID:	137397

  12. #12
    Quantum Mechanic danielkaiser's Avatar
    Join Date
    Feb 2003
    Location
    Riverside CA
    Posts
    1,061
    Quote Originally Posted by Slartibartfast View Post
    Lol!
    Here is a pic I took before It set in Arizona last year. Can you spot Mercury?
    Click image for larger version. 

Name:	IMG_1322.JPG 
Views:	128 
Size:	1.10 MB 
ID:	137397
    Upper left hand. What kind of filter, camera, and settings did you use?
    Daniel Kaiser

    "A mistake is always forgivable, rarely excusable and never acceptable." Robert Fripp

    AMD Phenom II x6 3.2
    Win 7 Pro x64
    8gig Ram
    Nvidia 640 GT 2Gb
    LW 11 x64

  13. #13
    Registered User Slartibartfast's Avatar
    Join Date
    Jun 2012
    Location
    Sweden
    Posts
    420
    Quote Originally Posted by danielkaiser View Post
    Upper left hand. What kind of filter, camera, and settings did you use?
    That's right. Except when watching the image from my iPhone, which rotates the image. Then it's the directional kind of right. Anyways, I shot it with an iPhone through the eyepiece of a 750 mm 6" telescope with a sun filter. Can't remember wich eyepiece I used at that moment, but I think 9mm. Or 17.

  14. #14
    Carbon fibre dongleŽ 50one's Avatar
    Join Date
    Jan 2011
    Location
    Honeycomb hideout
    Posts
    2,386
    There's also atmosphere magnifcation factor to consider...

  15. #15
    Quote Originally Posted by 50one View Post
    There's also atmosphere magnifcation factor to consider...
    Oh that's a good point, so what would the moon look like from above the atmosphere?
    http://universe-beauty.com/Space-pho...rmalearth-rise
    Not quite 1 pixel but it does look pretty small.

Page 1 of 2 12 LastLast

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •