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DIY True 4K Projector

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Re: DIY True 4K Projector

#21

Post by nitrogen »

huhtenberg wrote: post #12

Since the right people might be reading through the comments here - I've been looking at making a hi-res ceiling projector for a living space. Perhaps not one, but a set of several projectors with an overlap, but the key point is that they need to be placed in a way so not to interfere with the normal flow of life. Nor to be easily shadowed by people walking around, etc. This (likely) mandates placing them around the…

As another commenter suggested, it's common for projectors to have a movable/adjustable lens (also called lens shift) to move the projected image without altering focus too much.

There are also ultra short throw projectors that can be mounted a few feet away from their target, designed for classrooms. They probably don't have the blackest black levels though.

Re: DIY True 4K Projector

#22

Post by huhtenberg »

Someone wrote: post #16
huhtenberg wrote: post #12

Since the right people might be reading through the comments here - I've been looking at making a hi-res ceiling projector for a living space. Perhaps not one, but a set of several projectors with an overlap, but the key point is that they need to be placed in a way so not to interfere with the normal flow of life. Nor to be easily shadowed by people walking around, etc. This (likely) mandates placing them around the…

In principle, it is possible. A tilt-shift camera can bring any plane in focus, so running it in reverse will project the image sharply on your ceiling. See https://en.wikipedia.org/wiki/Tilt–shift_photography for cameras. https://www.projectorcentral.com/Understanding-Lens-Offset-a... learnt me that you can buy projectors that use this method. I suspect that back-projecting televisions ( https://en.wikipedia.org/wik…

Thanks, these are good leads.

Re: DIY True 4K Projector

#23

Post by huhtenberg »

lathiat wrote: post #14
huhtenberg wrote: post #12

Since the right people might be reading through the comments here - I've been looking at making a hi-res ceiling projector for a living space. Perhaps not one, but a set of several projectors with an overlap, but the key point is that they need to be placed in a way so not to interfere with the normal flow of life. Nor to be easily shadowed by people walking around, etc. This (likely) mandates placing them around the…

Look up "Short Throw Laser Projectors" it's somewhat possible with funky optics depending on how much distance you can afford.

Thanks. Can't seem to find how they work exactly except for "with mirrors!" remarks :)

Re: DIY True 4K Projector

#24

Post by jdboyd »

nitrogen wrote: post #21
huhtenberg wrote: post #12

Since the right people might be reading through the comments here - I've been looking at making a hi-res ceiling projector for a living space. Perhaps not one, but a set of several projectors with an overlap, but the key point is that they need to be placed in a way so not to interfere with the normal flow of life. Nor to be easily shadowed by people walking around, etc. This (likely) mandates placing them around the…

As another commenter suggested, it's common for projectors to have a movable/adjustable lens (also called lens shift) to move the projected image without altering focus too much. There are also ultra short throw projectors that can be mounted a few feet away from their target, designed for classrooms. They probably don't have the blackest black levels though.

A number of them support the unit being placed about 6in. from the wall. When you include the depth of the unit, that may be placing the mirror closer to 2ft. away, but that is still pretty darn close.

Re: DIY True 4K Projector

#26

Post by knodi123 »

bserge wrote: post #2

DIY Perks is a fantastic channel. So much good stuff, so little time to try everything :D

For fun, keep count of how many times Matt does something that you wouldn't have thought to do on your own, which would torpedo the whole project or be way too hard to self-diagnose.

I hit about 20 before I said "this project is way beyond my skill level." But I still got a vicarious sense of pride from watching his success!

Re: DIY True 4K Projector

#27

Post by knodi123 »

netsharc wrote: post #20

The audio seems to be a let down though: plug something into the (disassembled) phone's audio jack. I wonder if phones can deal with USB audio cards (that have surround options), or if there are any Bluetooth audio solutions that offer surround sound. Or I guess you can replace the phone with a PC/laptop, and have the display connected to an LVDS driver..

On an android, I assume you're not using any video sources that exceed the capabilities of a stereo jack. It's not like it's HDMI pass-through from a home cinema.

Re: DIY True 4K Projector

#28

Post by open-source-ux »

bserge wrote: post #2

DIY Perks is a fantastic channel. So much good stuff, so little time to try everything :D

He created an amazing 'desk PC' with computer components housed in a slim, completely silent enclosure and placed under a fold-down desk.

https://www.youtube.com/watch?v=QaoFh1DH51U

Re: DIY True 4K Projector

#29

Post by [deleted] »

huhtenberg wrote: post #12

Since the right people might be reading through the comments here - I've been looking at making a hi-res ceiling projector for a living space. Perhaps not one, but a set of several projectors with an overlap, but the key point is that they need to be placed in a way so not to interfere with the normal flow of life. Nor to be easily shadowed by people walking around, etc. This (likely) mandates placing them around the…

[deleted]

Re: DIY True 4K Projector

#30

Post by ben174 »

huhtenberg wrote: post #12

Since the right people might be reading through the comments here - I've been looking at making a hi-res ceiling projector for a living space. Perhaps not one, but a set of several projectors with an overlap, but the key point is that they need to be placed in a way so not to interfere with the normal flow of life. Nor to be easily shadowed by people walking around, etc. This (likely) mandates placing them around the…

I’ve seen applications where they use redundancy with overlapping projections to avoid shadows of people walking in front. The image is still slightly interrupted, but the overlapping projections do a decent job filling it in - if done properly.

IIRC academy of science sf did this in one of the lines for an exhibit.

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