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Old 08-09-2015, 04:38 PM
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GdB GdB is offline
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Default Re: A revolution in thought

Let's go back a little:
Quote:
Originally Posted by peacegirl View Post
A magnifying glass does not have the same properties as a camera lens. The light would be striking the lens at 12:08, but if the magnifying glass was put in front of a camera lens, the image would show up on the film at 12:00, although much larger.

Magnifying Glass Lens! How to use a Magnifying Glass as a DSLR Lens - YouTube
First, a camera lens is a magnifying glass. The only speciality is that it has a rather short focal length, so that on the small distance between lens and film/photo-chip, it can project a sharp picture on the film. Your youtube link shows that when you take the lens of a DSLR you must keep the magnifying glass at a great distance to get a picture on the photo-chip. So I have no idea why you say they are different.

Just to be sure that you checked: the guy on your video takes away the lens from his camera, and then uses the magnifying glass as lens for the camera. Right?

Now you say that when the sun is turned on there is first a picture of the sun on the photo-chip, and then after 8 minutes the light falls on the lens, the light goes through it and is concentrated on the photo-chip and... What? Does that make sense? What happens with the light falling through the lens? Why do we need the lens when the projection of the sun is already on the photo-chip?

Quote:
Originally Posted by peacegirl View Post
We would see the object in real time whether it was made larger by the magnifying glass, or not. It does nothing to negate the claim.
Yes, this is the misunderstanding above that I wanted to make sure of that you understand: the guy in the video removes the lens of his DSLR-camera. If he would not have done this he would not get a larger image of the sun, but a blurred one. Just take a magnifying glass, and try to see something far away bigger. You will not succeed. You do not understand anything of optics.

I try to order your reactions on my propositions, your reactions in bold, mine in italic.
  1. The image of the sun is pictured immediately on the film (photo chip in these days...) in the photo camera.
    Right
    OK, so here I understood you. Of course it is wrong, but let's go on.

  2. The image of the sun made by the magnifying glass appears immediately on the screen behind the magnifying glass
    A magnifying glass doesn't work like a camera. It enlarges what we see, or what the camera sees.
    Sorry, as said above, a magnifying glass works like a camera. If you use a magnifying glass to light a fire, you make a small image of the sun on a piece of paper, that then because of the concentration of the light, is so hot that the paper starts burning. Now if it is true that the image of the sun appears immediately on the paper, the paper should already start to burn before the light, i.e. the energy of the sun reached the magnifying glass. Does that make sense?

  3. Around the shadow of the magnifying glass the sunlight appears only after 8 minutes
    I don't want to compare a magnifying glass to a pinhole camera. Let's stick to cameras or eyes, okay?
    No. Pinhole cameras, real photo cameras work along the same lines: light fall through the pinhole or the lens, and project the environment on the backdrop.

  4. The image of the sun behind a pinhole appears immediately on the screen
    Right.
    OK, understood. But of course do not agree.

  5. If the hole is too big to create an image of the sun, the screen is only lit after 8 minutes.[/quote]
    No, it would just show a blurred image on the screen.
    So if I have a hole in a big box with the size of a basket ball, the backside of the box is lit immediately, during its environment becomes only visible in the sun's light after 8 minutes? And what in my room? The sunlight falls through the window, which is just a very big hole, so it makes a very blurred picture of the sun. And what if I put carton for my window, say with a hole of 2 by 2 meter? Do I have just less light in my room, or a bit less blurred picture of the sun? Do I see the furniture in my room immediately in this blurred picture of the sun in my room, or only after 8 minutes?

Maybe as a small change in view about the pinhole camera. It is true, the light that does fall through the pinhole is not affected by the pinhole. It just goes straight on. However, by blocking all other light around the hole, the light is stopped that would otherwise disturb the projection by the pinhole. For light that just goes through the pinhole, or goes to the place where the pinhole would be, nothing changes. So it is true what was said before: a pinhole does nothing with the light. The matter around the pinhole does something: it blocks light.
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But (08-09-2015)
 
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