[Ryan Steagall]

The two products that I tested were:

1. Parkland Plastics Polly-Wall

2. commercial grade curtain blackout material (I say commercial grade because I got some material that is 5+' wide.)


From about 40 hours experience with each, I've found that the blackout material stretched over a frame is the way to go for me. Comparing the two, I experienced increased black levels and richness of color with the blackout material. When pure white light hit the blackout material, I didn't experience eye-shock and the excessive ambient light produced from the Parkland screen. I also noticed a slightly softer picture while increasing detail and crispness. Maybe its because the blackout material isn't as reflective as the Parkland?


I consider going from Parkland to this blackout material a pretty effective "upgrade". Now that I've actually seen the difference between these two, I can only imagine what a Greyhawk or that Firehawk screen would bring. BUT, for the diy'er and the budget HT I will definitely suggest using curtain blackout material over the Parkland screen and stretching it PROPERLY over a sturdy 2x4 frame with inner braces. Rope lighting on the backside of the 2x4 frame with a dimmer is also a plus for proper bias lighting.


I hope the information that I've given helps and reduces some costly experimentation of time and money.

 

[Pagash]

Where did you find commercial grade curtain blackout material that comes in 5+' widths? Thanks for the great information.

 

[noah katz]

I'm curious if you've tried just a painted smooth surface and how it compares.


Thanks

 

[Ryan Steagall]

Pagash, My mother in law works for a window treatment shop. The fabric that i have had been folded and needs tobe ironed, but I do remember her saying how flat and nice it was when it was rolled out. By that token, I'm sure it was from a local fabric shop called "Handcock Fabrics" or maybe "Hobby Lobby".


noah katz, I have only experienced these two. The blackout material is a little more grey (not much) than the Parkland Plastics. I would think that a painted surface would be similar to the parkland plastics.


The two materials that i tested are not similar at all. One is hard surface and one is a fabric. I believe what I've experienced is the ability for fabric to capture and hold light in its threads rather than being so reflective as to create unwanted ambient light and blind you in scenes that contain a pure white.


The only way that I see a hard surface being able to retain the light is with pearlescence (sp) or some kind of glass beaded screen. I am no expert though.

 

[ziggyr]

redbone, blackout cloth is not a good reflector of light. You are quite correct when you say it ''captures light'', and that is the problem.

If you spray the cloth with a good quality pure white paint you will notice a significant increase in image brightness, contrast and colours. Just by painting it, you can end up with a great screen for the money - highly recommended.

If you spray some pearlescent clear paint over the top of the white you will get a screen with gain.

 

[Ryan Steagall]

ziggr, you make it sound like I'm complaining about the blackout cloth...which I am not. I actually think that its plenty bright without any painting. When I said "captures light" I was talking of that in a positive manner because this is a reduction in ambient light which washes the black out. If I wanted to paint something and have a smoothe surface, I don't think a fabric would be my first choice. I'd choose something that could gurantee me a more even coat of paint and a rigid surface.

 

[ziggyr]

That's fine redbone. It's just that in my experience, blackout cloth is noticeably less bright than any surface that has been painted with a pure white paint. Try painting a small scrap of blackout cloth and compare the projected images. Alternately, if you don't want to paint the cloth, try a painted piece if card and compare that to blackout cloth.

 

[Ryan Steagall]

ziggyr, thats cool. I might give that a try. I just don't understand why there would ever be cloth screens sold if painted anything was superior to cloth. This fabric compared to a hard matte bright white surface of Parklands appears to release a better picture. By this token I would think that fabric compared to a hard surface (painted fabric could represent this) has some kind of properties to capture and hold light within its threads that is giving me this better picture. Maybe the fibers are acting like the phosphers on the inside of a tube which capture and hold like to be viewed.


Just by comparing these very different materials I'm starting to believe that a fabric contains properties desired for PJ viewing.


Let me throw another idea out there... maybe all of these glass beads and pearelscence paints are cloning what is naturally seen on a fabric screen?


Ponder............

 

[ziggyr]

Redbone, what you are saying is not possible. Blackout fabric ABSORBS light which is an undesirable quality. You need to REFLECT light in a projection application. Blackout WILL ''capture and hold light'' which is the point I am trying to make - this is why the image is not as bright. The commercial screen fabrics (cloths) do not contain threads or fibres like this blackout stuff, they are VINYL and are then coated to enhance reflectivity.

 

[VideoGrabber]

redbone wrote:

> I also noticed a slightly softer picture while increasing detail and crispness. When pure white light hit the blackout material, I didn't experience eye-shock and the excessive ambient light produced from the Parkland screen.

 

[VideoGrabber]

Redbone wrote:

> Now that I've actually seen the difference between these two, I can only imagine what a Greyhawk or that Firehawk screen would bring. I experienced increased black levels and richness of color with the blackout material.

 

[Ryan Steagall]

delete old and bump...

 

[Ryan Steagall]

Actually its an infocus dlp pj


I've recently experimented more with the Parkland screen. I noticed an increase of clarity and color levels. I used a grey primer. I wonder how the picture would differ using maybe black, chrome, or maybe enough coats of white so the light doesn't bleed through the plastic.


Anyone experimented with this?


The parkland plastics by itself on a frame bleeds quite a bit of light through which could difuse and create lesser black levels.


Thoughts?

 

[artur]

Maybe painting back side of prkland plastic with flat black would increase black levels?

Artur

 

[scobro]

Redbone,

Does it matter what side of the Blackout Material you iron to get the wrinkles out.. When I bought mine they folded it up while I was in the store getting other supplies.


Thanks

 

[Ryan Steagall]

I don't believe that it matters. I ironed directly on the side that the pj would shine on. I didn't notice it to make any hotspots or anything. To be safe, I would iron the backside though.


Also, make sure you build a sturdy frame and stretch it properly. There are some articles on stretching canvas. This would be good for you to read.


If you use bias lighting, I'd also entertain putting some cheap panneling on the frame before stretching the material to prevent bias light bleed-through. Even though its "blackout" material, there can still be some light shine through it.


-Ryan

 

[Jesse S]

You don't need bias lighting with front projection. That's for "little" tvs

 

[Ryan Steagall]

Actually, this thread discusses it quite extensively and I believe everyone came to the conclusion that you do need bias lighting.

http://www.avsforum.com/avs-vb/showt...hreadid=106303