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Beam expander on a camera

RB astro

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what a science optics is.
Yep, exactly.
Fascinating, to say the least.

:beer:
 



paul1598419

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All of my childhood photos were in monochrome, or black and white, film. These were from the 1950s, but I remember having some very old cameras back then as they could be had at church sales for pennies. I had one box camera the you looked down into the top to see the view of what you were about to photograph. I don't recall how old these cameras were, but they were far older than I was. It would be interesting to have a camera collection of very old cameras to show how lenses progressed since the early 1800s.
 

paul1598419

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Pin holes have been around as long as I can remember. They aren't new or modern at all. The fact that a pin hole acts as a lens is how I watched the solar eclipse back in the early 1990s in Colorado.
 

steve001

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Modern cameras have come so far they no longer need lenses: https://digital-photography-school.com/make-pinhole-camera-dslr-body-cap/

I remember seeing much sharper examples, but these are a blurry disappointment.

Pin holes have been around as long as I can remember. They aren't new or modern at all. The fact that a pin hole acts as a lens is how I watched the solar eclipse back in the early 1990s in Colorado.
I did pinhole photography a longtime ago.
Long before the invention of photography there was the "camera obscura". As stated in the article a smaller hole will create a sharper image. Pinholes behave like a lens because it allows the photons of light to enter in parallel lines.
 

RB astro

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Nothing new about Pinhole Photography, just like Paul and Steve said !!
And as stated, pinholes act as lenses.
In fact you can prove this to yourself by pinching together your two thumbs and index fingers creating a small hole (aperture) and looking through it.
The tighter the hole, the sharper the image will become.
A camera lens acts the same way with its aperture blades and as the f-stop rises, the sharper the image becomes and less light is allowed through.
Basically the glass in the lens is used for magnification and the blades are used to regulate the amount of light that falls on the sensor/film.

RB
 
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Nutball

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Yea, I know. I just thought it funny how you can forget the lens and drill a hole in the cap on a $3000 camera. I remember looking through a tiny hole I'd make with my fingers a lot when I was a kid. I could seem to zoom in or out without ever loosing much sharpness as I changed the focus of my eye.

I wonder if more than one hole in series or parallel and of varying sizes would allow greater control and sharper images?
 

steve001

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Yea, I know. I just thought it funny how you can forget the lens and drill a hole in the cap on a $3000 camera. I remember looking through a tiny hole I'd make with my fingers a lot when I was a kid. I could seem to zoom in or out without ever loosing much sharpness as I changed the focus of my eye.

I wonder if more than one hole in series or parallel and of varying sizes would allow greater control and sharper images?
Each hole would create an image which might be interesting in and of itself.
 

Radim

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There's lots of talk about beam expanders on lasers, but how about using them on small cameras? Are the optics high enough quality? I assume so. Would a BE be compatible with camera optics? The idea would be to just slide a BE over a pocket camera's telescoping lens and maybe using magnets to hold it on, for the purpose of improving lighting conditions. Where can I find a good one to try? Ideally the small lens would be around 15-20mm, and the big one around 40-60mm.
Try it. I would recommend Dragon Lasers BE. It is however just 2x. But it has wide diameter, therefore the image will be less deformed. I would recommend you to get proper lens instead. You can get cheap lens for old 35 mm film cameras. Optics there is just awesome. Just make sure you can set aperture, for some electronic apertures you would need reduction.
 




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