TPro TW56X81 Lens Hood

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Many have reported internal reflections causing halos around bright objects (lenticular-fresnel halo), and hot spots on the screen. To reduce these reflections, there seems to be two things that work. One is lining the entire video cavity (behind the screen) with Duvetyne fabric... a blacker than black cloth that does not reflect light at all; or the other option is to build a lens hood that blocks the three lenses from having direct view of the screen. Since my 56X81 is still under warranty, I was a little hesitant to glue the fabric permanently to the inside of the video box,. Since most reported the lens hood as having the most positive effect, I opted for this "lay-in" hood that is easily removable. The goal of the lens hood is to prevent light reflected from the screen from re-entering the lens system, while still letting the light from the lenses reach the mirror.

This first pic is of the finished product:

The right side of the above pic is the rear of the hood.... the mirror end. Also notice the edge pieces and their half-circle oval cutouts. Originally I  did not have these oval openings, and discovered it needed these to eliminate partial blockage of the guns to the edges of the mirror. What is accomplished is that no surface of the three lenses has a view of the screen ; reducing ghosting and reflected hot spots.

Next pic is the completed hood, not yet covered with the Duvetyne fabric (and without the oval cutouts on the side (#3) edge pieces ):

This next pic below is the hood sitting in the lens cavity of my TW56X81. The upper image is from the mirror. Now you see why the ovals cuts were made on the edge pieces, the red gun is partially blocked:

Below are the basic pieces of corrugated cardboard I cut out. BTW, I did not use white surfaced cardboard on the final product. Pictured is a prototype made of the white surfaced cardboard, I then cut out another using brown (natural) colored cardboard. Although Duvetyne fabric does not reflect any light, a small amount will pass through it (to test, hold a piece of the fabric up to a light), and this is why I did not use the white faced cardboard in the finished product.

Base Piece 1 dimensions: 14.5 x 22.75"

Piece 2 dimensions: 15.75 x 5.625". This is the cutout (center missing portion) of the base piece #1. Centered left/right and back from the mirror end by 2.625". Again, you don't actually "make" piece #2, its the piece you cut out of the base #1.

Both #3 pieces are 3.75 x 7.625"

Piece 4 is 4.25 x 15.75"

The cutout piece 2 actually protrudes below the base piece a little, and is angled so the hood does not block the lens from reaching the bottom of the mirror. Here is another pic of the edge pieces with the angle line drawn (again missing the oval cutouts seen in the finished product):

To construct, simply cut out all pieces needed. Then cover both sides of all pieces with the Duvetyne fabric, then assemble. Duvetyne fabric has a fuzzy side, this side goes out. I used the 3M 77 spray adhesive. Use kerosene to remove the adhesive from your hands.

The verdict: noticeable improvement!! I compared parts of movies that had scenes with halos (shows a "halo" around a bright object on a dark background), these were greatly reduced (but not completely); and contrast increased. Also, hot spots were reduced. Highly recommended!

Thanks to Craig Rosenthal for making it all possible.

 

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