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Thread: Two sources of light?

  1. #1
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    There has been a lot of talk about the wrong angle of shadows on the moon. The logic is that there should be only one source of light, that is, the sun. But aren't there actually two sources - the sun AND the earth? If the moon is a source of light to us at night then the light of the earth on the moon must have some bearing on things.

  2. #2
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    Yes, but consider that the Moon casts shadows at night, but not when it's visible in the day. Ok, so the Earth would be brighter than a full Moon, but it's still insignificant when compared to the power of the Sun. I once thought that the Earth would provide 'fill-in' light for the photos, and it probably does contribute something. However, it has been shown that the Lunar surface itself would provide the vast majority of the indirect lighting.

  3. #3
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    Although the Earth is in the lunar sky, it is no more a factor in lighting the scene than the Moon is on Earth when both the Sun and Moon are in the sky. It is simply overwhelmed by the Sun.

  4. #4
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    On 2002-03-30 17:58, Kaptain K wrote:
    Although the Earth is in the lunar sky, it is no more a factor in lighting the scene than the Moon is on Earth when both the Sun and Moon are in the sky. It is simply overwhelmed by the Sun.
    Ah hA and End Run around the
    Shadow Angle issue of 11
    its understandable..

    Source was consider.

  5. #5
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    4:18 A.M. March 31, 2002 Yawn?
    Ok so just how high above the Lunar horizon
    was the Sun on July 20th `69 from 4:17pmedttill 1:55pm
    E.D.T "lift-off" July 21st was a monday?
    This of course would be an Astronomical ?
    {in other words how many bucks to get an answer}
    and not an astrological one about how to
    RIDE backwords in space to ones loved 1
    so no i don't really know HOW HIGHT the Sun
    nor would i expect to know with any amount
    of certanity within my life time. Its a liberal
    collage naturally and there are many Liberal
    programs tht give many liberal results Realitiv to the Son of course

  6. #6
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    On 2002-03-31 05:36, HUb' wrote:
    4:18 A.M. March 31, 2002 Yawn?
    Ok so just how high above the Lunar horizon
    was the Sun on July 20th `69 from 4:17pmedttill 1:55pm
    E.D.T
    JayUtah told me in another thread that the Sun was 10.8° high at the time of the Apollo 11 landing. He says he got it from the flight plan.

    This jives fairly closely to my Starry Night program, which showed the Sun at 12° up, about 24 hours after sunrise.

    http://www.badastronomy.com/phpBB/vi...ic=726&forum=3

  7. #7
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    The flight plan presumed the original landing site. Since Apollo 11 overshot the landing site I think the actual sun angle may have been between 9 and 10 degrees. Since local horizon and slope would easily exceed the tolerances we're talking about, it's not important to quibble about a degree or two. I think "approximately 10 degrees" is as precise as we can or ought to be.

  8. #8
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    Just to clear up the sun angle issue.

    The 'Classic' ref: http://www.hq.nasa.gov/alsj/a11/as11-40-5903.jpg was taken at 110:42:14 = 04:14:15 UT (GMT) 21/Jul/69 (ref: http://www.hq.nasa.gov/office/pao/Hi...p11events.html
    Sun angle at 14 deg 32 min says my software. (Starry Night Backyard v3.12).

    For Jay/JonWitts who have http://www.ApolloHoax.com forum backup: viewtopic.php-topic=707&forum=12&start=25.htm

    BTW My calculations tallied exactly with Mr C.Crunchers. Go figure! [img]/phpBB/images/smiles/icon_wink.gif[/img]

    <font size=-1>[ This Message was edited by: Slime (Silky Smooth) on 2002-03-31 17:01 ]</font>

  9. #9
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    Slime, I never did get your backup files to work. Sorry. I never did find out how to open RAR files.

  10. #10
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    John: WinRAR or WinAce 2.x+ will decompress the files. Its just like using WinZip.
    Download WinRAR from http://www.rarsoft.com or WinAce from http://www.winace.com. Theyre free. They can also take over from WinZip should you wish.
    Just make sure you get the password from Jonathan Ploegman. The forum files are for a select few.
    Double click on the RAR file only once the file archiver is installed.

  11. #11
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    I always love this topic. To me this is one topic that shows that the moon hoaxers know nothing at all.

    First of all, let's say that there were two distinct sources of lighting. If you look closely at the shadow produced, you would not one shadow but two. If you've got overhead lighting, like banks of fluorescence lights similar to those that I have over my desk at work, you can see multiple shadows. So if the moon hoaxers claims of multiple lighting sources are true, we should see multiple shadows. Try it and you'll see.

    Now on to the Earth lighting. While it is true that the Earth can illuminate the lunar surface, this can only happen when the moon's surface is not illuminated by the sun. A full Earth reflects about 40-50 times the amount of light that the moon does (bigger and more reflective)and that's still not that much. By the time the reflected light expands and reaches the moon, it is a negible component of surface lighting.

    A full Earth from the lunar surface could only been seen when the Earth has a new moon (or close to it) and you're on the side facing the Earth. This of course did not happen during Apollo.

    There is a second source of lighting and that is the reflections off the lunar surface which can be anywhere from 6-14% of the incoming solar energy.


  12. #12
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    Very true about the shadows. Multiple lights cast multiple shadows, or essentially no shadows if sufficiently distributed or diffuse.

    Single lights cast single shadows, but oriented radially from the light source. Hoax believers always like to explain the foreshortened shadows and differing shadow lengths as the result of a single nearby light source. It's always amusing to watch them hem and haw when I point out that the shadows would diverge not converge due to a nearby light source!

    Then they advance to the claim that each object has its own light source, illuminating only that object, and casting the converging shadows. When you point out that such a lighting setup would create "pools" of greater illumination around each object, in order to avoid casting multiple shadows, they counter by saying bright overhead fill light would even out the lighting. And thereby, I say, subdue the shadows.

    The standing challenge is reiterated: I say to the hoaxers, put your money where your mouth is. You all have lights. You all have studios. Show me the lighting setup you all "expertly" claim was used to produce your photos. Show that it produces the effects you say it would produce. How strange that all of these "professional photographers" and "professional filmmakers" who claim it was all falsified can only offer vague descriptions. A demo would be very easy to set up and far more convincing than handwaving.

  13. #13
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    I think a quote from Von Braun is appropriate here,

    "One test point is worth a thousand expert opinions"

  14. #14
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    Jay is correct here. Since I spend my days shooting stuff in the studio with a bunch a of lights, I have to concur that there would be telltale signs of multiple lighting setups. I am a hard light guy, meaning I use mostly spotlights. I am very good with barndoors, snoots, scrims and gobos, and work very hard to make my photos appear to the casual observer as if only one light source is being used. But there is always evidence that multiple lights have been used if you know where to look. The shot I just finished this morning was the interior of a travel trailer. It took 17 lights to do this shot, coming from all over the place. When you view the image you get the feeling of the sun streaming throught the window. Careful inspection shows not only carefully hidden cross shadows but HIGHLIGHTS from every light. I spend a lot of time disecting lighting schemes of the best photographers in the world and you can always tell where the lights were and what kind they are. The apollo moon images are no execption. The lighting is from the sun.

    In my professional opinion as a lighting expert the HB's don't have a clue about lighting.

    <font size=-1>[ This Message was edited by: infocusinc on 2002-04-04 12:16 ]</font>

  15. #15
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    I think that if the landings are faked, the fakers would be bright enough not too use obvious studio lighting so the HBers are on the wrong track here as regards to finding evidence of a hoax.

  16. #16
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    Hi, and welcome, infocusinc. Thanks for the insightful (pun intended) contribution.

  17. #17
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    My experience with lighting has all been in the stage variety, which means I don't know a whole lot about photography lighting instruments, but I do know a whole lot about lighting and sightlines -- i.e., viewing lighting setups from different angles.

    The problem with David Percy and Bart Sibrel is that while they both claim to be professional filmmakers, the science of dissecting a photo to determine how it was done is more along the lines of photo analysis. That's a different set of skills. One doesn't have to be familiar with the physics of light and the optics of perspective in order to take very compelling and artistically laudable photographs.

    David Groves, PhD, the image analyst most often cited by David Percy, is actually an expert in reconstructing 3D geometry of objects based on how they're lit in images. This does not necessarily translate to expertise in extracting lighting setups from images. It may, but there's no guarantee.

    A good example of where it all goes wrong for them is the alleged boot highlight on Aldrin's egress. Percy and Groves -- the Davids, as we've come to call them -- argue that the highlight is the hot spot produced by a studio light which Groves claims to be able to locate relative to the photographer with amazing sub-inch precision.

    Well, in order to locate anything with sub-inch precision, it must be fairly small in size itself. No use in trying to locate a 24-inch diameter light or a huge eight-foot diffuser with sub-inch precision. That simply doesn't make sense. So the postulated light source must be very small indeed. In fact, if it's only 12 inches from the camera, it's probably only four or five inches in diameter.

    A funny thing happens when you illuminate a scene with a small luminaire -- you get sharp-edged shadows. You fix that in one of two ways: use a large-area light source, or use many light sources so that any one individual shadow doesn't matter.

    We know neither of those was done with the Aldrin photo. You can't say that a large-area light source is exactly a certain number of inches from the camera. A large area light source won't make a small hot spot on a boot heel. In fact, Infocusinc uses large reflectors to make big highlights on convex objects, rather than the pinpoint highlights you would get from small luminaires. And if they had used multiple lights there would be multiple hot spots, one for each light.

    Another funny thing happens when you set up a small light and then photograph the scene from a point twelve inches to the left of the light. You not only get the hard-edged shadows, those shadows very closely follow the outlines of objects in the scene. We've all seen this happen in our snapshots. The flash is separated by only a few inches from the lens, providing a very small phase angle.

    Certain features in the Aldrin photos (e.g., his PLSS hoses) are ideal for producing those closely offset shadows. Yet not one close offset shadow is seen in the entire set of half a dozen photos which Percy says were illuminated by this small phase angle and a small light source.

    In short, this lighting scenario just doesn't add up. And it doesn't take a lighting expert to see the flaws in it. Fortunately lighting experts do see flaws in the theory.

    Logically this is what we call an ad hoc explanation. An observation is made (the boot hot spot). An explanation is formulated to satisfy the observation (there was a supplementary light used). Deductively this would be an affirmation of the consequent and would be rejected forthwith. Inductively, however, this is the beginning of the scientific method. We have

    A implies B

    and we have observed B, and theorize that A is causing it. However, A has certain other consequents: C, and D. Therefore if B is asserted and we wish to test "A implies B", then we should observe

    A implies C
    A implies D

    But in this case we do not observe C and D. Thus some other antecedent, X, must be at work, i.e.,

    X implies B

    Especially when we note that

    X implies F
    X implies G

    and observe F and G in this case, we have a winner according to the scientific method.

    My challenge to David Percy: you have lights; you have a studio. Duplicate the lighting setup you say produced this photo, and show that it produces a reasonably identical photo, complete with everything we observe in Aldrin's egress, and nothing we don't observe.

  18. #18
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    Hello again, Mr Infocus. Glad you came?

  19. #19
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    [b]I think that if the landings are faked, the fakers would be bright enough not too use obvious studio lighting[b]

    The issue is not so much that standard studio lighting would give itself away as it is that the lighting effects we observe in the photos cannot be practically achieved by any system of artificial lights, commercial or otherwise.

    To produce a uniform field of artificial illumination ("wash" in the industry jargon) that is purely unidirectional, able to produce hard-edged shadows, and up to hundreds of feet in size is practically impossible.

  20. #20
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    Of course, if it wasn't actually done in a studio, but somewhere in the desert of Area 51...???

  21. #21
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    Hello Johnwitts! of course Im glad I came.

    Jays point about small lights is correct. and in the ladder images there are no shadow lines that match what would be created by a small light near the camera. The key to unraveling this is not the shadows but the highlights. If what is seen on the boots is a highlight from a small light or flash, then where are the specular highlights from that light in the rest of the scene? Given the reflective ladder and the mylar film all over the place, we would expect to see small point highlights everywhere. They are just not there. The highlights that are present in the ladder and the foil are very broad and from the bottom of the scene. They are reflective highlights from the lunar surface. Also notice the directions of the shadows on Aldrin. They are on the tops of the folds and creases in the suit. This can only happen if the light comes from below. You would not get the same shadow effect from a light that was equal to or higher than the lens.


    BTW...forget the Mister Infocus...just plain old Craig will do.

  22. #22
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    On 2002-04-04 19:18, The Rusty Lander wrote:
    Of course, if it wasn't actually done in a studio, but somewhere in the desert of Area 51...???
    But the problem is the behavior of the dust seen in the videos couldn't be simulated unless it was in a vacuum.

  23. #23
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    Jay,

    It makes no real difference if you light for photography, film, video or stage. The fixtures are all of the same basic design and function. SUre there is contrast range of the lighting to consider. Stage lighting may have the most latitude, since the humam eye adjusts. Film and Photography should be kept in an 8 stop range give or take. Video can take even less.

    In my experience, having worked with a number of filmmakers and videographers (we are talking about guys like Percy and Sibrel...reportage and industrial/commerical work) "lighting" is term taken very loosely. I think the correct term might be illumination. Put some lights in place that cover the scene and are flat and pleasing. Lots of near camera lighting with umbrellas to open up the shadows. Pretty basic stuff. This is not a putdown but rather a just the way things work. Most commerical video/film guys shoot tons of scenes a day in someones factory or office. They have to move and work fast. Most times a light bounced off the ceiling and an simgle umbrella or small softbox high and right of the camera will do the job. Its also the nature of the medium. With movement and sound to keep the viewers attention, lighting becomes less of an issue. It just has to look pleasing, since no one is going to study it frame by frame. Stills on the other hand are a moment frozen in time, allowing the viewer to study the nuances. Its a much more exacting medium lighting wise.

    I too would second your challange. Those who think it can be done should give it a try and show us the results. A picture is worth a thousand words.

  24. #24
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    I always love when the HBs use the Buzz Aldrin photo to try and prove one of their points. If you look at the original photo,

    http://www.hq.nasa.gov/office/pao/Hi...1/20130708.jpg

    It's easy to see that they over exposed the photo to bring out the bright spot on his boot.

  25. #25
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    It makes no real difference if you light for photography, film, video or stage.

    To some extent I agree. I know there are some basic differences.

    Film and television use a "key/fill" principle to establish contour by controlling shadows. On the stage we cannot do this, especially in the theater where I volunteer, which is in-the-round. Key 'n' fill would create a poor sightline. We use color more than intensity to establish contour and depth.

    I know photography uses much more light quantity than typical stage lighting. During my brief stint in a photo studio we drew the contract to photograph a college graduation and the stage illumination was quite inadequate. We had to place photo lights to "flash" and provide the appropriate number of watt-seconds for suitably short exposures.

    It's a typical misconception that stage illumination is of the same quantity as photo studio illumination.

    I suspect the principles of shadow elimination are the same. I use the deck and the set pieces to reflect light. And of course we use fresnel washes and circles of ellipsoidals to minimize shadows.

    Stage lighting may have the most latitude, since the humam eye adjusts.

    Most theater takes place in pitch darkness, although almost no videography or studio photography does. Even one fresnel with a deep blue gel and dimmed up to the point of minimal incandescence will illuminate my stage to make basic shapes visible to anyone in the audience.

    Pretty basic stuff. This is not a putdown but rather a just the way things work. Most commerical video/film guys shoot tons of scenes a day in someones factory or office. They have to move and work fast.

    Agreed. This is why I don't believe David Percy knows as much about the finer points of lighting as he means us to believe. I've been videotaped in "quickie" setups using basically one diffused key light and ambient for the fill.

    When we light a theater scene, we have the luxury of mulling over it for weeks and taking up to an hour or two to "tweak" it when the instruments are hung and focused.

    Stills on the other hand are a moment frozen in time, allowing the viewer to study the nuances.

    An essay on this was the first page I wrote for Clavius.


    <font size=-1>[ This Message was edited by: JayUtah on 2002-04-04 22:45 ]</font>

  26. #26
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    On 2002-04-04 22:02, jrkeller wrote:
    I always love when the HBs use the Buzz Aldrin photo to try and prove one of their points. If you look at the original photo,

    http://www.hq.nasa.gov/office/pao/Hi...1/20130708.jpg

    It's easy to see that they over exposed the photo to bring out the bright spot on his boot.
    JayUtah can correct me, but I seem to recall him saying something about the scans on alsj generally being underexposed, so this may not be a legitimate criticism.
    Everything I need to know I learned through Googling.

  27. #27
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    After looking at the alsj photo, I wouldn't doubt that the photo could be underexposed. However, if you look at some of the HB's sites, its obvious to me that the their photos are overexposed. In some cases, the surface of the moon is so white that you can barely see any details of the surface.

    This photo is in several books I own (the exposure seems good about halfway between the alsj and the HB's photos) and the "hot spot" is barely visible.



  28. #28
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    5:18 A.M.? PST.
    oh my I see once again
    THAT I have been out numbered
    hip hip .. do a trip.. for the More's better bunch
    now back tho the D'bait
    fist the how many Li.ght sources
    once upon a time returning home from grade school
    I looked up above the trees {in daylight}
    and saw a very bright star in the sky over a tree
    it was very very bright [actuall it was venus]
    but never mind the details. It was so bright
    that day that when i turned around and looked
    to the north behind me I could see my shadow
    from the STAR. So I will include Venus LI`ghts 2.
    now about the lack of cmmunications
    {um on CB ch 14 at 1400Z} about the
    14 or 10 or 9,8,7, degree angle of the Sun
    over the Lunar Horizon on July 20th..
    { no I don't now believe July eithor } its April
    and whatever these so called X.spirts say
    the Shadow angles in the Pictures in the
    book "We Reach the Moon" {not me I can tell You 4sure}
    i'd give you 20 and say i still Don't see it
    your way. theres one more issue as long as i've
    all these deleted line to fill in.. only i 4get
    what it was and must scrool back >> scrooling:
    Knaw looks like to much ** even to allow room
    in my buffer to reach back that far..
    So i'll be at the next Full Moon.. and
    my moon shadow in the Sun.LI.T,ea hours
    um say 1400 or better when the Suns 10 degrees B4 set?

  29. #29
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    HUb', was that your first experience with recreational drugs? (When Venus created your shadow in daylight, I mean.)

    Will you be using the same chemical when you look for your shadow under the full moon during daylight? Just need to know so I can properly digest your post.

  30. #30
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    Kipp Teague opines that the JSC scans from the 1980s are dim due to limitations of the scanner used to create them.

    It is very likely that the prints of Aldrin's egress, from which high-resolution scans were made, have been "pushed".

    I surmise neither scan accurately depicts the exposure on the original transparency.

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