Prof.'s DIY screen

[fisher191]

<^..^>Smokey Joe wrote:

Oh and the answer to your previous Q......2 weeks....the standard time period for 4 weeks or more.
I used to fiddle with mixes it all the time, now I dabble on occasion.

Hi Joe, I have been snowed under at work and have done nothing yet. Did you make any progress on a mix that we can make with locally available paint?

Alternatively what is the best mix you have seen that is made with local paint? Anything is likely to be better than the random flat white I used.

Greg

[Harpmaker]

Prof. wrote:

Well after much deliberation and procrastination, and taking into consideration what I'm trying to achieve with my new screen..(which is mainly to get a bit of extra pop to some of the colours)..I've decided to venture into the world of "The Grey Screen".

Don't fear the Gray Screen, Gray is Good!

...although, I've been comparing the test panel against my screen, so I suspect that the whites might be OK when the new screen is up..

It sounds like you may have fallen into the trap of comparing white and gray screens side-by-side. That never really works. The projected whites on the gray screen will be duller than on the white screen (some compensation can be gotten from using a metallic mix, but not a lot). Look at the reference photos of my screen in the first post of the Cream&Sugar thread. A white Kilz2 and C&S #1 panel are shown beside two Black Widow panels. The BW panels are much darker than the two light panels, but when the light panels are removed, the whites appear very white on the BW panels.

Interestingly enough, I discovered that when I watched some movies on a 5 panel composite screen (see my last post in the C&S thread) I didn't really see any lack of black in the image. In round numbers, the composite screen panels ranged from about N9.2 to N8.8. But when I started watching a movie I knew well because I had taken screen shots of it before, I knew something wasn't right with the image. I tried adjusting my PJ to compensate and nothing I did worked. It was still missing the "pop" or "snap" that I got from the same movie on a Black Widow screen.

I've also tried a different silver in the same ratio mix, and this was even lighter than the silver I had been using..Infact I could barely tell the difference between the white reference panel and this silver mix!!..so I'll be staying with the original silver for my first Grey screen..

It amazes me how similar looking silver paints can act so differently when used in a simple mix with white paint.

[Prof.]

Harpmaker wrote:

It sounds like you may have fallen into the trap of comparing white and gray screens side-by-side. That never really works. The projected whites on the gray screen will be duller than on the white screen

Yes, one could easily dismiss a grey screen next to a white one as not being very good at reproducing whites..and I guess the only way I'm ever going to know is to make up a complete screen..

Interestingly enough, I discovered that when I watched some movies on a 5 panel composite screen (see my last post in the C&S thread) I didn't really see any lack of black in the image. In round numbers, the composite screen panels ranged from about N9.2 to N8.8. But when I started watching a movie I knew well because I had taken screen shots of it before, I knew something wasn't right with the image. I tried adjusting my PJ to compensate and nothing I did worked. It was still missing the "pop" or "snap" that I got from the same movie on a Black Widow screen.

Are you saying that the C&S panel didn't give any "pop" to the image?

It amazes me how similar looking silver paints can act so differently when used in a simple mix with white paint.

That other silver I tried was Mica based!!..colour sparkles everywhere..

[Harpmaker]

Prof. wrote:

Are you saying that the C&S panel didn't give any "pop" to the image?

Compared to the white Kilz2 panel, I would say a little, but not near as much as a darker gray such as BW. I would also say that the "pop" factor is very subjective.

I would recommend going to an art store and buying small tubes of acrylic paints in Munsell N9 gray and N8 gray; they might be called Neutral 9 and 8 grays, but I think the Munsell color space is international. You can use these to make your own color swatches and use them to visually compare your test panels to see what N value they might be.

That other silver I tried was Mica based!!..colour sparkles everywhere..

Amazing isn't it how one brand has 'em and another doesn't. Both paints could be mica-based, it has something to do with how they coat the mica flakes.

[Prof.]

Harpmaker wrote:

I would recommend going to an art store and buying small tubes of acrylic paints in Munsell N9 gray and N8 gray; they might be called Neutral 9 and 8 grays, but I think the Munsell color space is international. You can use these to make your own color swatches and use them to visually compare your test panels to see what N value they might be.

That sounds like a good idea..It would be interesting to see where they fall in the N range..

[Prof.]

Just when I thought I had finished with all my test panels and was ready to start painting the new screen, some new developments have happened..
I recently came across some interesting Craft paints and mediums, one of which is a new product..and it looks like something I've been looking for as a supplement to the paint mixes..
One of the other products produces a clear barrier between various paint colours, so there is absolutely no bleed through of individual paint colours and layers..

Basically what I'm hoping these paints and mediums will do is to give me a very light silver/grey screen with some gain.!!

When all the products have arrived I'll be making up some new test panels..
This new screen won't be a simple paint mix formula that you put on with just a couple of coats..
At the moment it looks like it will be a four layer paint application, but should still be within the realms of most DIY screen painters....Oh, and no RGB components..

[mechman]

Prof.,

I want samples of everything for the ol' spectro!

[Harpmaker]

Prof. wrote:

Just when I thought I had finished with all my test panels and was ready to start painting the new screen, some new developments have happened..

Bwaahahahahaha! (evil laugh, in case you can't tell ) He is one of us now!!!

Seriously Prof., sounds great and looking forward to more info and photos!

[Prof.]

mechman wrote:

Prof.,

I want samples of everything for the ol' spectro!

Will do mech...
The sample layers will be thicker than the rolled panels..Will you still be able to get accurate spectro readings, the same as what the actual screen will be?

[Prof.]

Harp,

What you don't know is that I've been one of you for many years.. ..I've just been dormant for awhile..

I designed the first DIY ultra high gain screen back in 2004, and have made numerous types of screens since then..

[Harpmaker]

Prof. wrote:

Harp,

What you don't know is that I've been one of you for many years.. ..I've just been dormant for awhile..

I designed the first DIY ultra high gain screen back in 2004, and have made numerous types of screens since then..

My humblest apologizes DIY Screen Master! I bow before your greatness!

The Sleeper has awakened!

[Prof.]

..Hey..I'm not even in the same league as you guys.
The only measuring instrument I've ever had is my eyes!!..

[wbassett]

Hey you have an icon and not all of us do so we need to catch up!

Doing by eye isn't a bad thing when you're setting up your own screen. You can tailor the screen to your projector, setting, and personal preferences. We deal more with making recommendations across a wide range of projectors, so having a screen that we know will work equally as well with projector A as with projector B is an important factor.

I've seen some DIY screens (even some commercial screens for that matter) where the developer obviously preferred a cooler image so their screen was a bit biased towards cool (blue), or some that were a warm screen. Then I've seen some people rave, while other's loathed the screen. If a screen is cool and a person prefers a warm image, then of course they aren't going to be happy with it.

Also if we can get the materials that you use I'm sure mech will do some readings on it for you.

[mechman]

Prof. wrote:

Will do mech...
The sample layers will be thicker than the rolled panels..Will you still be able to get accurate spectro readings, the same as what the actual screen will be?

As long as the paint sample is as thick as the sample I sent you, we should be fine!

[Prof.]

wbassett wrote:

Doing by eye isn't a bad thing when you're setting up your own screen. You can tailor the screen to your projector, setting, and personal preferences. We deal more with making recommendations across a wide range of projectors, so having a screen that we know will work equally as well with projector A as with projector B is an important factor
I've seen some DIY screens (even some commercial screens for that matter) where the developer obviously preferred a cooler image so their screen was a bit biased towards cool (blue), or some that were a warm screen. Then I've seen some people rave, while other's loathed the screen. If a screen is cool and a person prefers a warm image, then of course they aren't going to be happy with it.

So true...I've always leaned towards a more cooler screen and have made them accordingly..
I'm hoping to keep this new design more neutral so it will be suitable for a wider range of applications..

Also if we can get the materials that you use I'm sure mech will do some readings on it for you.

This is one of the things I'm trying to achieve...To try and standardize the various paints and mediums, so that they can be purchased almost anywhere..
Silver has been the biggest problem with all the variations that have been used, such as Harps silver in the C&S mix, being available only in the US from just one store..
In this new formula, I'm using two different silvers, which won't be all that difficult to find and won't need to exactly the same to achieve the desired effect..
In this application, the silver will only be a secondary reflective element, not the main reflector..

[Prof.]

mechman wrote:

As long as the paint sample is as thick as the sample I sent you, we should be fine!

[Prof.]

Finally, all the paints and mediums have arrived..except one..More about that later..

Itching at the bit, so to speak I couldn't wait any longer to start on the new test panels, so I decided to make up the first panel with just three layers instead of the four I had originally planned..having not received the other medium..

I had earlier made up several panels with the Dulux Flat White as just the base coat..
That is the First layer

The Second layer of this test panel consists of a mix of Faux Matt Glaze, and 3 Metallics..
This is the proportions I used..

Faux Matt Glaze...100 ml..
Metallic Silver......10 ml. This is the Aluminium or silvery sparkle based paint..similar to Harps silver..
Metallic Silver......10 ml. This is the Mica based silver..similar to Delta Ceramcoat
Metallic White.......5 ml. This is Titanium coated Mica..and is semi transparent..also known as irridescent white..

When this coat had dried, it had quite a sheen to it and you could see sparkles very clearly across the whole panel..

The Third layer and the final top coat..

Here I used a mix of 25% Dulux white and 75% Faux Matt Glaze..
This muted the sheen produced by the metallic mix and provides an almost matt finish..( under viewing conditions I couldn't detect any hot-spotting)

The missing fourth layer was going to be between the White base coat and the Metallic mix layer..
This was going to be a Faux Gloss Glaze, applied directly over the White layer, which is used to completely seal the White layer from the Metallics and of course gives a gloss finish to the White base, thereby increasing the reflectivity of the white, without any loss of intensity of the Matt White..

After the panel had dried, I put it up on my screen along side of the white reference panel while just watching some TV..
What I saw really surprised me..It looked very good and almost what I've been looking for in a new screen..
I couldn't believe my luck in getting it so close in the first test panel..

Comparing it to the white reference panel, the whites were slightly better and the blacks were about the same..This is the area that I'm going to have to work on a bit, to try and improve the blacks..

Colours looked nicely balanced and I didn't notice any blue push..But that might just be me since I've always liked a cooler image..

Viewing cone..170 degrees..no problem..

There is even a little bit of extra ambient light rejection with this layered mix..compared to the reference panel..but this certainly is not going to be suitable for anything but a light controlled theatre..

While I'm waiting for this Faux Gloss Glaze to arrive., I'll try adjusting some of the mix quantities to see if I can improve on the blacks a bit more..

I wasn't able to get any shots last night, so I'll try to get some done tonight..

[cynical2]

Interesting stuff, Prof! Keep the details coming!

[Prof.]

Thanks Jim...Will do..

Here's a shot of the new layered panel..
On the left is the White reference panel, in the middle is the new layered panel and on the right is the 3:1 White/Silver panel..
This was taken with the flash from about 4' away..

As you can see, there is very little difference between the white panel and the new panel, but this may change in the endeavors to try and improve the blacks..

[Prof.]

In keeping with the trend to give a name to ones new screen designs, and for the sake of easy reference, I've decided to call this layered paint approach.."The Silver Pearl"..(all rights reserved..)..

Here are some colour band shots showing the first test panel on the right..
As you can see , it has a bit of extra gain over the white reference panel but still maintains the same brightness at the wide viewing angle..




All I have to do now is to increase the "Greyness" a little, to bring up the blacks a bit, whilst still keeping the good whites and colour balance.. and at the same time, try to maintain the excellent viewing cone..