1. StarGazer

    StarGazer Member

    In this thread we'll be examining the very first image taken from space from a V-2 Missile and the claim related to it:

    [​IMG]


    You can find a recent article regarding the V-2 image here: http://earthsky.org/space/this-date-in-science-first-ever-photo-of-earth-from-space:​

    [​IMG]

    The 35 mm camera has a normal lens, therefore flat earthers assume that since there is no curvature with a normal lens then the Earth must be flat. However:


    [​IMG]

    The aperture opening was f/5.6, with the shutter opening reduced to 17 degrees.

    The lens aperture is usually specified as an f-number, the ratio of focal length to effective aperture diameter. A lens typically has a set of marked "f-stops" that the f-number can be set to. A lower f-number denotes a greater aperture opening which allows more light to reach the film or image sensor.

    The specifications for a given lens typically include the maximum and minimum aperture sizes, for example, f/1.4–f/22. In this case, f/1.4 is the maximum aperture (the widest opening), and f/22 is the minimum aperture (the smallest opening).

    [​IMG]


    Here is how much curvature we expect to see using Walter Bislin's curvature calculator for an altitude of 104 607 meters ( 65 miles) with 35 mm lens.

    [​IMG]

    http://walter.bislins.ch/bloge/index.asp?page=Flat-Earth:+Finding+the+curvature+of+the+Earth


    Since Walter hasn't included lens aperture option in his program, I'm finding trouble the determine how much curvature there is for the camera specs of the V-2 missile.
     
    Last edited: Oct 2, 2017
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  2. StarGazer

    StarGazer Member

    Here you can watch a video of the V-2 launch:





     
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  3. deirdre

    deirdre Moderator Staff Member

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  4. Trailblazer

    Trailblazer Moderator Staff Member

    Rotated to horizontal. The picture doesn't have great contrast, but I think it's clear there is curvature visible.

    curve.
     
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  5. Trailblazer

    Trailblazer Moderator Staff Member

    Lens aperture will not affect the field of view of the lens - that is just a function of the focal length (the "35mm" part). Edit: Actually the 35mm description is not the focal length of the lens: see below

    The aperture controls how much light can pass through the lens, but it doesn't reduce the field of view of the lens. That might seem slightly counterintuitive, but all the aperture is really doing is limiting the number of different paths that light can take from an object onto the image plane. (This also has the side-effect of making the image sharper, at the expense of making it less bright.)

    Side note: the part about the shutter opening being "reduced to 17 degrees" refers to the circular shutter of the movie camera. The shutter is a rotating disc, with a segment missing to let the light in. The smaller the segment, the shorter the effective exposure time will be:

    [​IMG]

    It again doesn't have any bearing on the field of view.
     
    Last edited: Oct 3, 2017
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  6. StarGazer

    StarGazer Member

    Does that mean that all it has to be done is to crop 17° of the horizon from Walter's simulation and the camera settings in his app are identical to the V-2 camera?

    [​IMG]
     
  7. Trailblazer

    Trailblazer Moderator Staff Member

    No, as I said above, the 17 degrees is the size of the shutter opening (exposure), and has nothing to do with the field of view.

    However, you are assuming that the "35 millimetre" description refers to the lens.

    It actually refers to the 35mm film format: the camera used Eastman Super-XX 35mm film:

    [​IMG]

    So we don't know the focal length of the lens, and thus we don't know the field of view.
     
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  8. Trailblazer

    Trailblazer Moderator Staff Member

  9. Mick West

    Mick West Administrator Staff Member

    You’d also want to know if there is any lens distortion, ie if the lens is rectilinear or not.
     
  10. StarGazer

    StarGazer Member

    [​IMG]
    This image is from year later 1947 and 100 miles altitude.
    The V-2 image of this thread is from 1946, 65 miles altitude.
     
  11. Rory

    Rory Senior Member


    Having watched the video, I'd say there are several places where curvature is evident - but also that it appears some lens distortion may be occurring. Or, at least, that it can't be ruled out.​
     
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  12. Trailblazer

    Trailblazer Moderator Staff Member

    Yes I thought that initially but then the page also claimed it was the first one from space, so it was unclear. (Space is normally defined as above 100km, or ~62 miles.)
     
  13. StarGazer

    StarGazer Member

    I can see a small curve, but as Mick pointed out above, we have to determine if the lens is rectilinear or not.
     
  14. Ray Von Geezer

    Ray Von Geezer Senior Member

    "Stretching" due to aspect ratio changes may also be flattening the curve? The inset in the YouTube video is 1.55:1, a modern format used as a compromise to display on either normal or widescreen TVs, so almost certainly not original - I'm pretty sure common ratios for that time would be 1.33:1 or 1.375:1.

    Similarly, the photographs in the OP look like 16:9 which as Deirdre pointed out means they've been cropped or stretched, including the one on Earthsky where the FE meme appears to have been taken from.

    The images where curve is most apparent are the 1:1 photographs, but again if they were taken from the video they've very likely been cropped or reformatted too.

    Ray Von
     
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  15. StarGazer

    StarGazer Member

    I might be onto something:

    The V-2 footage was filmed with camera model DeVry nicknamed "The Lunch Box"

    [​IMG]

    Source Link: https://www.quora.com/How-did-the-c...ph-of-the-earth-from-space-survive-the-flight

    But the source link is somewhat inaccurate regarding the DeVry model, because the picture from above is for a hand crack version of DeVry.

    I found a video where you can have a closer look of the hand crack DeVry model, unfortunately the lens is not mentioned:


    5 min 9 seconds into the video

    The DeVry camera had to be automatic:

    [​IMG]

    Source link: http://nebraskahistory.pastperfectonline.com/webobject/2FFA7111-12EF-4E92-90C4-414283392753

    [​IMG]

    Source link: https://www.google.co.uk/amp/s/www.pinterest.com/amp/pin/93309023510460308/

    The lens of the automatic DeVry camera could be Wollensak Velostigmat F3.5 lens:

    [​IMG]

    Source Link: https://www.google.co.uk/search?q=v..._AUIEigB&biw=360&bih=512#imgrc=O1guWwgeQMhc1M:

    But that lens doesn't look like the lens from the article below. Or it's the same lens?

    [​IMG]
     
    Last edited: Oct 11, 2017
  16. StarGazer

    StarGazer Member

    It's obvious that the automatic DeVry camera does not have the same casing as the one used for the V-2 Rocket:

    DeVry Comparison.

    I found a pdf document named: ''High Altitude Research Using V-2 Rocket by The John Hopkins University Applied Physics Laboratory'' that needs a detailed analysis.

    Link: http://www.dtic.mil/dtic/tr/fulltext/u2/636108.pdf

    This is another hint that the lens used was Wollensak Velostigmat F3.5

    [​IMG]

    DeVry V-2 Rocket.
     
    Last edited: Oct 15, 2017
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  17. StarGazer

    StarGazer Member

    Found stock image DeVry camera after recovery:





    Pictures Taken From V2 Rocket (1946)(1).

    Pictures Taken From V2 Rocket (1946)(2).
     
  18. StarGazer

    StarGazer Member

    Found camera specs DeVry camera:

    DeVry Camera.


    Camera Specs 1.

    Camera Specs 2.

    Source DeVry Brochure provided by Cesar A. K. Grossmann, active member and researcher from Quora
     
    Last edited: Oct 28, 2017