Rear Projection

I recently builded a (jentle)curved rear projection screen, using a bright polycarbonate and grey rear projection foil.
In combination with short throw projectors. There was absolutely no loss of quality compared to front projection.The only thing to make sure is that the bulb of the projector is below or above the field of view, otherwise you will have a bright spot.

Also, if using rear projection, the distance sitting from the screen and image dimensions need to be balanced to avoid pixels being to big.

I have been in search of a good rear projection screen that wont break the bank but yet has a good enough quality that I can live with. I have now experimented with two inexpensive options; white opaque shower curtain, bed sheet ( 500 thread count). Here are my comparisons for all its worth;

Brightness: The Bed Sheet was much brighter than the Shower Curtain, but almost too bright. Some of the lighter colors became washed out. The opaque shower curtain reduced the brightness a little more that I liked, so a slight advantage goes to the Bed sheet here.

Color: The bed sheet produced better colors ,but again, sometimes to bright.
Slight advantage to the bed sheet again.

Lens hot spot: The clear winner here was the Curtain, and no hot spot could be seen even with the projector at eye level. The Bed sheet had serious issues here, even when I lowered the projector so that the lens was blocked from direct viewing.

Overall smoothness: The vinyl curtain gave a more professional looking image than the bed sheet.


Summary: No Clear winner, as each surface had different strengths & weaknesses. If it wasn't for the dull image brightness, I would probably stick with the curtain.

Are there any other surfaces that should be considered?


I saw the previous post mentioned;
"a bright polycarbonate and grey rear projection foil."

I would love to have more detail on this as well.


~Polmer

Quote:

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Originally Posted by Polmer

I have been in search of a good rear projection screen that wont break the bank but yet has a good enough quality that I can live with. I have now experimented with two inexpensive options; white opaque shower curtain, bed sheet ( 500 thread count). Here are my comparisons for all its worth;

Brightness: The Bed Sheet was much brighter than the Shower Curtain, but almost too bright. Some of the lighter colors became washed out. The opaque shower curtain reduced the brightness a little more that I liked, so a slight advantage goes to the Bed sheet here.

Color: The bed sheet produced better colors ,but again, sometimes to bright.
Slight advantage to the bed sheet again.

Lens hot spot: The clear winner here was the Curtain, and no hot spot could be seen even with the projector at eye level. The Bed sheet had serious issues here, even when I lowered the projector so that the lens was blocked from direct viewing.

Overall smoothness: The vinyl curtain gave a more professional looking image than the bed sheet.


Summary: No Clear winner, as each surface had different strengths & weaknesses. If it wasn't for the dull image brightness, I would probably stick with the curtain.

Are there any other surfaces that should be considered?


I saw the previous post mentioned;
"a bright polycarbonate and grey rear projection foil."

I would love to have more detail on this as well.


~Polmer

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You might try the bed sheet idea again with a much lower thread count. 150-200 might help to eliminate the hot spot. It will also lower the surface brightness as the weave will be more coarse.

Polmer,

To go a little deeper into the polycarbonate and foil. The polycarbonate is in fact the same as plexiglass but the difference is that it is very easy to bend it or drill holes or whatever, it will not break. You can use plexiglass as well, the result will be the same.

The grey rear projection foil is the standard foil used to build rear projection screens, you can find them at the companies building the screens, I contacted a few of them and received a few samples. The standard foil is not that expensive at all if you compare it to the rest of the cockpit stuff, it costs off course a lot more then a bedsheet but the overall result is not comparable.

Also if you have rear projection, you are sitting much closer to your screen so you don't need as much as you would be sitting further away.

I've used what they call Party Table Clothes (white) made from kind of plastic. I got the best results, of all mentioned above, and would use it again if I had to. It was $1.60 USD for a single 10 by 6 sheet. I ended going to front projection and the results were even better. Super white material.

I have been in search of a good rear projection screen.
I have tried a high thread count liner, as well as a white shower curtain.
I have posted my reviews of these (earlier in this thread), but I wanted to post that I have finally found what I was looking for!

I sent a email to "Dazian" who makes professional screens & rear projection material and asked for a sample. They sent me back a vinyl material that was opaque & light gray in color. This got me thinking about the shower curtain idea again, but now I knew what to look for.

So today, I go to the home Depot ( A USA hardware store) and found a shower curtain Liner made by Zenith. It is called Zenith Bath styles Shower Liner, color ; Clear, Model # H28K. It is not actually clear, but a kind of fogged vinyl.

Anyway, I got home a checked it out.............Wow.
It is actually brighter on the reverse side that it is on the projection side!
You cant see the projector halo, and the colors are fantastic.

If anybody is interested, a link to the product is supplied below.
If you are experimenting with rear projection ( due to cockpit room size restrictions like I am ) give this a shot. Its only $8 us dollars.

http://www.mclendons.com/item.asp?sku=10293330


The only thing I would like is a bigger sheet. The one a bought today was 70" x 72" ( 178cm x 183cm).



Regards,

~Polmer

Quote:

---

Originally Posted by Polmer

I have been in search of a good rear projection screen.
I have tried a high thread count liner, as well as a white shower curtain.
I have posted my reviews of these (earlier in this thread), but I wanted to post that I have finally found what I was looking for!

I sent a email to "Dazian" who makes professional screens & rear projection material and asked for a sample. They sent me back a vinyl material that was opaque & light gray in color. This got me thinking about the shower curtain idea again, but now I knew what to look for.

So today, I go to the home Depot ( A USA hardware store) and found a shower curtain Liner made by Zenith. It is called Zenith Bath styles Shower Liner, color ; Clear, Model # H28K. It is not actually clear, but a kind of fogged vinyl.

Anyway, I got home a checked it out.............Wow.
It is actually brighter on the reverse side that it is on the projection side!
You cant see the projector halo, and the colors are fantastic.

If anybody is interested, a link to the product is supplied below.
If you are experimenting with rear projection ( due to cockpit room size restrictions like I am ) give this a shot. Its only $8 us dollars.

http://www.mclendons.com/item.asp?sku=10293330


The only thing I would like is a bigger sheet. The one a bought today was 70" x 72" ( 178cm x 183cm).



Regards,

~Polmer

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Thanks! Projectors are on my list.