Among the first White or Gray Spandex applications considered involved using a solid substrate for backing and a "skin" of Spandex over the top. White paint, Gray paint, Silver metallic paint, even using Mirrored Mylar was even attempted by a few.
There would be no reason one could not effect a dual layer affair with a Solid Surface or Opaque cloth / Spandex build.
But not enough was said about how how difficult and expensive the construction is when building a frame that is both rigid and stout enough to handle the degree of tension required to stretch BOC across a frame that is over 7' high and 13' wide. Easily, the lumber and braces alone can cost more than the Cloth itself. And every piece must be straight, the corners and braces cut very exact, and the entire frame not have any degree of twist. The latter being something that many DIY'ers have had out of necessity to use Tension-style Wire & Turn Buckle assemblies to correct twists that develop even when using expensive, hand picked clear lumber and extreme care during assembly. Switch to Aluminum Tubing and specialized attachment methods, and the cost rises even more.
, while it is easy to say how easy something is, and make a reference about what one has done before, without providing details, real actual information as to how the build was done, the PJs used, and other important variables should accompany any such offerings. I'd personally like to know more about the big screen you posted an image of...the "bedsheet" one. In that photo I see the entire area illuminated by a Flood Flash, even the white trim underneath the screen to the right & left, yet the image looks to be not washed out at all. As one with some degree of experience building larger screens, and taking photos of 'em as well, so what is seen in your image is nothing short of remarkable in the extreme.
Let me give you an out....was the PJ used over 4000 lumen and the color of the screen a ultra dark gray? Was the PJ hung very close to the screen? (...I can't see it in the photo...)
On a different Thread you recently posted on http://www.avsforum.com/t/1436181/110-diy-spandex-at-screen/300#post_23082529
you mentioned that you had to order a special Fabric for a 10' screen, then you painted it. Can you pull these facts together and clarify exactly what you used, how you managed to get "bed sheet fabric" taunt enough to allow for the pressure of a roller to apply paint evenly, and what type of material it was.
I find it difficult to grasp that any High Thread count Cotton or Rayon material deemed satisfactory enough for use as a bed sheet, and available in a size larger than any "California King" sized could either be inexpensive enough to compare to the large sized BOC, referenced to, or be able to accept enough paint onto it's surface without a substantial amount soaking through. And the size frame? What materials did you use to construct it, and most of all, tell us how you managed to do it all in just a couple hours"? Paint included? It just doesn't seem likely...it seems impossible given all the years of postings by BOC users that have painted normal sized screens and all the steps taken and time consumed doing so.
Please don't feel that this is a "I'm callin' BS" post, it's not that, but it is a request that if you have something of note to offer, a more through explination...especially any method or materials that can help other DIY'ers get to where they want to go in the most effective and inexpensive way possible, then post up some real information that is helpful and informative.
Lastly, and for the record...I don't "Guess" about anything I post. I either speak directly from experience, or reference the experiences of others, or do so from using a combination of both sources. I really feel that the type of posts and the information I provide, as well as the extensive follow-up I give other DIY'ers pretty much makes that point very clear. To that effect, it may well be better for avsforumun
to go with a mfg screen and hope for the best from it. I can say without fear of contradiction that if he wants to have at least occasional access thru that Case opening, even a lightweight, Dual Spandex affair is going to be a PITA to have to deal with.