SI Black Diamond clone? - Page 5 - Home Theater Forum and Systems - HomeTheaterShack.com

Reply
 
Thread Tools
post #41 of 47 Old 08-12-13, 06:23 PM
Banned!
Rob
 
Join Date: Jul 2013
Location: New York
Posts: 43
Re: SI Black Diamond clone?

I will explain these pics in a sec.
Attached Thumbnails
SI Black Diamond clone?-rear-1.jpg  

SI Black Diamond clone?-rear-2.jpg  

SI Black Diamond clone?-rear-3.jpg  

SI Black Diamond clone?-rear-4.jpg  

Daylightuser is offline  
Sponsored Links
Advertisement
 
post #42 of 47 Old 08-12-13, 08:12 PM
Banned!
Rob
 
Join Date: Jul 2013
Location: New York
Posts: 43
Re: SI Black Diamond clone?

On the pics in the last post, I wanted to ask if anyone had tried a hybrid approach for rear front projection.

Normally, rear projection is only possible where there is sufficient space behind the screen. For a non-DIYer, it is also dependent on the willingness of the user to pay $10,000 for a mirror on stilts to go behind the screen. One could be forgiven for thinking that some screen companies are a little out of touch with the market. Hard to imagine feeling like I had a good deal at that price. It's easy to see why the technology never became mainstream. You see them on ebay at that price. I always wondered if anyone ever bought one and was happy about that?

Anyway, I digress. I have found a manufacturer who claims to be able to supply a black screen fabric for rear projection and a very dark grey charcoal black front projection fabric. The latter looking similar to the black diamond 0.8 gain screen in color (only). I ordered 100 inch by 60 inch rolls of both. My interest in these is mainly for work (I have a displays business). But, it struck me that they may be relavent to this topic for obvious reasons. Rear fabric can sometimes work as front fabric if a reflective surface is applied to the back and the front isn't too glossy.

I see this DIY project as having 2 parts. One is the ambient light rejection component with the complexities of micro louvers etc. The second, which may be as interesting if not more for some, is creating a screen with that black or dark finish that looks stylish and offers a greater enhancement to perceived contrast than current grey options. Black does look more high tech and flat screen tv-like. The second component is relavent here.

Even though I prefer the look, I don't use a rear projection set-up at home because I don't have enough space behind the screen to get a decent sized image. My wife would also be unhappy if I knocked down the wall separating the living room and our bedroom (even after seeing the improvement in contrast! I know, I know...)

The price of mirror rigs has always seemed outrageous too. Even though I'm well off financially compared to most, I would feel like an idiot giving these people $10,000 for a mirror. I don't care how flat it is.

Over the weekend I was thinking about a hybrid approach where the projector and screen stay in the same place but I project down onto a mirror on the floor behind the screen and the screen is mounted on a stand like the "fast fold" screens. I did some mock ups of the concept in the images in the previous post. The 2nd coffe table positioning of the projector would be good for people who don't want to ceiling mount.

The screen could even be attached in between two book shelf units to create a dark space if the room is really bright or the projector very dim. Like a rear projection tv that blends into the room. It is a lot easier to make a black rear projection surface with no hot spots than making it reflective enough for front. It is also a more effective way of dealing with ambient light in the absence of micro embossed films and that's what this screen color is really about.

Now , I know the mirror in the pic is too small for the position of the projector etc but that is just details.

This method is also a good way of reducing the throw distance without buying an expensive short throw lens (which can cost north of $2000 on their own).

I have found a local place that can sell me a glassless first surface mirror that is lightweight and large enough to use on a 120 inch screen with very little space. It even comes on its own stand on wheels that makes it position able at the right height and angle. It can be cut to a different shape for tight angles and costs less than $400 for one that was 8 feet wide and 4 feet high. $400 sounds like a lot for a DIY project you could say. True, but 10 times less than a comparable sized optical mirror from a well know screen manufacturer. For the more daring, they also sell a DIY option that you shrink onto a flat surface using a hair dryer. This apparently gives the same results if you start with a flat surface and do everything right. Assuming you have skills, $80 will let you make one of any size you could fit in your house (within reason). Btw, first surface, is a term that means a mirror that doesn't have glass in between you and the reflective surface like a bathroom mirror. That glass is a problem for this purpose. Some will tell you they won't work at all. In my experience, they will but you'll loose brightness and get brightness uniformity issues.

You can also get smaller but perfect used mirrors off ebay that have been taken from rear projection tv's. they seem to go for $40 - $120. You could buy the whole tv for the same price if you want to go get it. Interestingly, not all of the mirrors taken from these tv's are first surface. I don't know why but perhaps they came from inferior or older models?

Can anyone think of a reason why this couldn't work?

As a stop gap, I was also thinking of using one or two of my ultra short throw projectors set to rear projection. I could place them on the floor behind the screen. I have one that can give a 120 inch image with a little over 1 foot of space (less than the tv stand currently takes). Maybe it could be a pull down screen attached to a shelf to be invisible when not in use too. I use some weights at work that are designed to keep these films flat when used in a suspended role up design. I would probably mount the black material on some glass to give it that edgeless look. In my head it is some stylish glass with rounded corners with two holes in the top corners that allow it to be suspended with invisible string to give that floating in mid air, frameless look. I see no reason to make it look just like a tv which I see as an ugly black box.we don't have the same limitations so we can free the screen from the black box and create cool designs. Specifically taking advantage of the non-fixed screen size to allow a giant theater like screen for movie night that doesn't dominate the room when not in use. Have you seen that Sharp 80inch lcd? The wife would never allow such a monstrosity in our living room.

I have no idea if either the black or charcoal fabric work with ultrashort throws. I know from experience that optical screens usually struggle. Glass beads, for example, suck with ultra short throw unless you sit on the ceiling.

As well as the front / rear idea, I would also like to know if anyone has experience with black rear projection fabric? I would like to know how well it performed. I have already been warned about a narrow viewing angle so there is one limitation but they all have that (except the draper high performance). I guess I'll see for myself in a few days.

Also, I would love to hear any experience with the da-lite 3d virtual black and 3d virtual grey. These seem to be indicated for 3d only. They are not claiming it is good for 2d. In fact, they suggest having 2 screens. I would love to know if 2d is at all watchable but with limitations or just completely unusable?

The fabric I ordered is nothing like the da-lite 3d btw. This is from a manufacturer in Australia who also supplies me with led screens from their facility in china. Their fabric is for 2d and 3d (active). The da-lite seems to have been released under the radar but seems to be a relatively low cost (for them) commercial dark screen. It is a shame if it only works for the one content type that nobody above the age of 6 cares about. You can buy it as a DIY fabric though. Perhaps they released it before everyone agreed that 3d wasn't the next big thing after all?

$800 will get you a piece to make your own decent sized screen. I find it hard to imagine there being much of a market for a DIY fabric at $800. Especially if it doesn't work for 2d which is a fairly large flaw by any standards.

They aren't the only ones with their heads in the clouds. I have a supplier who sells black optical fabric and fabric with micro louveredfilter filters for sunlight rejection. I had forgotten all about them. I became a reseller last year and then put their info to one side when they sent me their dealer pricing. A piece of the micro louveredfilter film to me was more than $2500 for anything over 100 inch. They expected me to add a mark up and sell that here even though they have no brand recognition in the US. I told them that I could sell one screen, even if I added no mark up at these prices.

It is no wonder projection has such a hard time in the mainstream. Clients will always look at a roll of DIY fabric at $2500 as an obscure product with limited application. With the price of pro projectors, they prefer the more reliable led screens which is a shame because all you see up close is a bunch of dots. Anyway. Enough complaining from me!
Daylightuser is offline  
post #43 of 47 Old 08-12-13, 08:17 PM
Banned!
Rob
 
Join Date: Jul 2013
Location: New York
Posts: 43
Re: SI Black Diamond clone?

Quote:
mechman wrote: View Post
You either need a better camera or you need to learn how to use a camera better. No offense but I have yet to see a good picture from you. And as for the materials/methods, we can't really judge them by your pictures I hope because again, I have yet to see anything that looks good.

Are you using a cell phone camera? I can't tell because there is no EXIF data in your pictures either.
I am using a cell phone camera. As an FYI, saying "no offense" before saying something offensive doesn't stop it being offensive. I don't have to post anything. I don't get paid for this.

They aren't the best pics but you can see, for comparative purposes the difference between screens. Now add something constructive or say nothing. I don't care about your critique of my photography. For someone who is so sensitive, you don't make much effort to be polite. If this forum has no interest, read another one or post something better.
Daylightuser is offline  
 
post #44 of 47 Old 08-12-13, 10:34 PM
Banned!
Rob
 
Join Date: Jul 2013
Location: New York
Posts: 43
Re: SI Black Diamond clone?

Just got some polyester mesh screen printing fabric. Works very well as a light diffusing layer and is cheap. $27 for a piece large enough for a 120 inch screen.

It works well as rear projection fabric too but our interest is for it's use as a translucent light diffusing layer. The results pics show it with a piece of dark tint - (actually an ipad privacy screen that also just arrived). Behind the tint is a piece of aluminum. All very crude as it only just arrived. More testing with better, larger pics tomorrow.
Attached Thumbnails
SI Black Diamond clone?-fabric.jpg  

SI Black Diamond clone?-look.jpg  

SI Black Diamond clone?-rear-pro.jpg  

SI Black Diamond clone?-result11.jpg  

SI Black Diamond clone?-result2.jpg  

Daylightuser is offline  
post #45 of 47 Old 08-14-13, 07:35 AM
Shackster
 
Join Date: Jul 2013
Location: Sweden
Posts: 11
Quote:
Daylightuser wrote: View Post
Just got some polyester mesh screen printing fabric. Works very well as a light diffusing layer and is cheap. $27 for a piece large enough for a 120 inch screen.

It works well as rear projection fabric too but our interest is for it's use as a translucent light diffusing layer. The results pics show it with a piece of dark tint - (actually an ipad privacy screen that also just arrived). Behind the tint is a piece of aluminum. All very crude as it only just arrived. More testing with better, larger pics tomorrow.
Rob, I like what I see! I know you have no more than two hands, but it would be awesome to see a white board held up right next to your test with the iPad privacy film. Judging from the picture, it appears the test with the privacy film has somewhat lower gain than a regular 1.0 gain screen, on the other hand the surface is much darker. I've seen your pics from the glass bead test and it truly looks impressive! Wouldn't that work as a final screen? Any disadvantages?

Regards, Patrik
Patrik is offline  
post #46 of 47 Old 08-14-13, 03:36 PM
Shackster
 
Join Date: Jul 2013
Location: Sweden
Posts: 11
Re: SI Black Diamond clone?

Hi everyone!

I know the 3M Vikuiti rear projection film have been discussed here earlier, but got dismissed due to the fact that it wouldn't work as a front projection surface, but I found a vid on youtube were a guy walks behind a 3M vikuiti film and it still looks impressive.
A found this picture on a 3M retailer website >>



And this is how a glass bead screens works (for those of you who wonder) >>



It's very similar except the gloss layer in there between. 3M Vikuiti comes in rolls with a width of 47.24". I'm curious to see for my self! Have anyone tried this?

/Regards, Patrik
Patrik is offline  
post #47 of 47 Old 11-22-13, 05:44 PM
Shackster
 
Join Date: Nov 2013
Posts: 85
My System
Re: SI Black Diamond clone?

With the mirror-diffuser-tint/darkening pattern, rear-projection has the obvious benefit where projector-light only needs to pass through the darkening layer once (instead of in and then out = twice for front projection). So rear-projection would allow more brightness(with same tint) OR a darker tint(and same brightness) compared to front-projection. Also, a less effective diffuser won't hotspot as noticeably until it's so thin that you're getting blasted with light in your eyes.

Mirrors for the rear-pro could be inexpensive to aquire either via secondhand stores or by making your own out of mylar over a frame. I don't remember if it's been mentioned here yet, but reflective mylar AND diffusing sheets can usually be found (affordably) looking for hydroponic/greenhouse supplies. Also, don't underestimate a $2-3 thin, frosted, showercurtain as a fun trial into rear-projection.

I wish it was easer to just find old CRT rear-pro screens that weren't cracked or didn't require you to also haul and then recycle a broken CRT TV. The cracked one I was fortunate enough to play around with had fantastic front light rejection AND side-to-side viewing angles. It's up/down angles were narrow, but they also don't matter to anyone who's sitting and watching the screen (you only need something like a 10degree arc).

Last edited by Ftoast; 11-26-13 at 05:46 AM.
Ftoast is offline  
Reply

Bookmarks

Tags
black , clone , diamond , si

Quick Reply
Message:
Options

Register Now




PLEASE COMPLETE ALL REQUIRED FIELDS BELOW... THANKS!

REQUIRED FIELDS ON THIS PAGE
YOU MUST COMPLETE ALL OF THESE

Username
Password
Confirm Password
Email Address
Confirm Email Address
Random Question
Random Question #2




User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
PLEASE READ BELOW PRIOR TO ENTERING AN EMAIL ADDRESS!

ATTENTION!

YOU MUST ACTIVATE YOUR ACCOUNT!

Activation requires you reply to an email we will send you after you register... if you do not reply to this email, you will not be able to view certain areas of the forum or certain images... nor will you be able download software.

AN INVALID EMAIL ADDRESS WILL CAUSE YOUR ACCOUNT TO BE DELETED!

See our banned email list here: Banned Email List

We DO NOT respond to spamcop, boxtrapper and spamblocker emails... please add @hometheatershack DOT com to your whitelist prior to registering or you will get nowhere on your registration.


Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML is not allowed!
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 


For the best viewing experience please update your browser to Google Chrome