Has anyone compared the daylight "readability" of the red screen vs. Darkstorm's smokey grey screen? I've been using the red screen and am wondering if the smokey grey provides more contrast of the VFD to make it more readable. At night the red is awesome.

I've read on the riocar.org FAQ that of all screens, the red one provides the least amount of contrast during daylight hours and is therefore least readable. I'm finding that my Empeg is virtually NOT readable during daylight hours even with indirect sunlight. My dimmer is working ok, but I suspect I have a non-AR coated screen since it has a very shiny finish. But, as the the FAQ suggests, AR coating doesn't significantly improve the readability anyway. Any thoughts?

--Andrew

My thoughts: Red sucks during daylight and anything is better .

Yeah, Smoke is a lot better...

IMO, smoke is MUCH better than red in sunlight. It also happen to come close to matching my dash. If you can live with blue-green display I would go with the smoke lens.

Red is generally considered the worst as far as visibilitry goes, due to how far away on the light spectrum it is from the actual color of the display. The display itself is sort of a teal color, somewhere between green and blue. So either the blue or green faceplates should be the brightest, because less light is actually being filtered. I use the green, and although it's pretty bright, it is still unreadable if it's in direct sunlight.

So, my question is, how does the smoke compare to the green or the blue? Anyone make this comparison?

So, my question is, how does the smoke compare to the green or the blue? Anyone make this comparison?

I think DarkStar has at least two different smokes, I have a light smoke for my MkI and it is more readable in bright light, but with sun hitting it directly it suffers from the fact that the display unit reflects alot of light, making it look like even the unlit pixels are lit...

/Michael

This makes me wonder...

Like you said, one of the reasons that the display is hard to read in sunlight is because the sun brightens the unlit portion of the display.

Is there a such thing as "one way" shading, which allows light to pass through glass in one direction but not the other? You could then essentially shade the inside of the colored lens so that sunlight didn't go into the player, but light from the VFD got out. Is there such a thing?

Closest thing would be a polarizing filter. Was intending to get one to try, but then
I got my (first) MkII...

/Michael

Someone please remind me: does reflection on dielectric cause polarization (if so, in which plane), or rotation of polarization plane? In other words, is it possible to use a polarizer in the lens to reduce visible reflections from the screen? (Hm, I guess that if this were possible the empeg guys would have used it... )

Hmmm, yeah, since my car has red instrumentation the lighter smoked red (as shown in the 2nd to last pic here on Darkstorm's page)
http://personal.mia.bellsouth.net/mia/d/r/drkstorm/Empeg.htm
might solve my brightness problem, but direct sunlight reflected off of the VFD guts is still an issue...
--Andrew

I don't think so. I suggested the possibility of using Polarising film to do this but to be honest I didn't think it would work. It would depend on the Phosphor on the VFD elements rotating the polarised light by 90 degrees (or thereabouts). I think this is very unlikely. Instead, I think the Phosphor would randomise the light again so that it wouldn't be polarised any longer. I don't have any evidence that this is what would happen, it's just my gut feeling. If by chance the Phosphor reflected back the polarised light without any (or little) randomising or rotation then we'd need a filter that rotated the light 45 degrees. It would have to rotate the same way (or opposite ways depending on how you look at it) because you would want the two 45 degree rotations to be added together otherwise you'd get no net rotation. Now, I don't know if there is any kind of film that will rotate light this way. Anyone else know of such a beast?
Of course the downside to using a polarising filter is that it blocks out significant amounts of light and this might be too much to make the VFD viewable.
Am I making sense? Does anyone else know more about polarisation & rotational filters?

I've tried all 4: smoke, red, blue & green in my Denali. It is low in the center console so it is rarely hard to read however I would crudely rank them blue>smoke=green>>>red. I prefer the smoke because it matches the other faceplates such as trip computor etc.and my teal dashlights (otherwise I would use the blue)

Well, I don't know squat didly about "rotational filters", but I think you guys are on to something.

There has to be something that only lets light pass one direction. Maybe somthing they use in Flat panel monitors? or LCD displays?

What about coating the VFD with something? Another non glare layer, or mirror perhaps?

Can the VFD be completely replaced?

Damn... I'm going to be spending the rest of the day thinking about this now...

Unless it's a reflective LCD like in the newer handhelds, LCDs suck outside. The reflective ones actually use the sunlight to make the screen look better, but it's still iffy to get the right light.

OLED on the other hand looks pretty decent. I'd love to see the next gen empeg car product use an OLED screen.

What about that plastic that mirrored sunglasses are made from?

As a side note to my last post, I just did some searching, and found this article on "One Way Mirrors" on some physics site called Physlink. In a nutshell, it sounds like true oneway mirrors are impossable, but that doesn't mean oneway filters aren't...


Question
What is a one way mirror and how does it work?

Answer
A "one way" mirror is actually a partially transparent mirror. Light reflects from this sort of mirror, but some light also goes through it. In fact, ALL mirrors are partially transparent, but manufacturers paint the back of the mirror with black paint.

To produce the "one way" effect, the partial mirror is used to divide two rooms, then one room is kept dark while the other room is brightly lit. People in the brightly lit room see a mirror, since the image of the bright surroundings is reflected by the partial mirror. People in the darkened room don't see their reflections, instead they see THROUGH the mirror, and can watch the people in the brightly lit room.

If you suspect that a particular mirror is being used as a window, simply turn the lights off in that room, then place a bright flashlight against the mirror surface. If there is a hidden chamber behind the mirror, the flashlight will illuminate it, and since you're in a darkened room, you'll see the hidden chamber.

A genuine "one way" mirror is impossible to build because it violates the laws of thermodynamics. If you made up a box of "one-way" mirror material which was oriented so more light flows into the box than flows out, then more and more light would flow into the box and build up there. It takes energy to do such a thing. If genuine "one-way" mirrors existed, they would serve as energy sources, and you could use one to build a Perpetual Motion machine.

Yeah, LCDs work on a similar principle. They rely on a couple of polarising filters and the ability of a Liquid Crystal to rotate that polarised light to create a kind of 'Light Valve'.

"Lisa, in this house, we obey the LAWS OF THERMODYNAMICS!!!"

Sorry, couldn't resist.

Even if the sunlight that makes it through a polarized filter is randomized on reflection, only the component that is in phase with the polarization will make it back out again. I think there is a good chance that some sort of polarizing film would significantly reduce internal reflections. Now, it may have too strong an effect on the VFD light too, but it is probably simpler to find some polarized film and stick it on and see what happens.

Someone on this board has had moderate success with a circular polarizing filter. Ill ask him for more info. Finding a polarized lens, coating the front with a optical quality ar coating, and coating the back with a mirror coating would be nice. This would take care of the light reflecting back off the vfd and washing it out. However, the trouble with normal polarization is that if you are looking at it from the wrong angle, it doesnt work correctly. Not sure how much of the vfd light that will block though. I'll look into some possibilities.

OK, seems the concensus on visibility (brightness) is:
blue>smoke=green>amber>>red

Beaker, where does your OHP idea fit into this equation in terms of visibility and the 3 other criteria?
2) color - OHP can print any dang color. I'm assuming the lighter the screen color, the closer the text color will be to the natural greenish color of the VFD. (Remember I'm trying to match the red instrumentation of my dash.)
3) Glare - Based mainly on how shiny or matte the top surface of the screen. Some have suggested using 600 grit sandpaper, sandblasting, or some AR coating.
4) VFD reflection - direct sunlight being reflected by the unlit portions of the VFD display. Problem mainly experienced in sunny California; not ready to move to the UK (althought the customer service is better there, I hear). arrreerrrr, different thread....

Beaker, how do you attach you OHP film? Do you use a clear plastic lens? Does it have a matte finish? Do you mount it outside of inside of the lens? Does Macromedia Freehand work with your Corel 5.0 files?

--Andrew

Having used smoke, blue, and green faceplates in my car, I would revise your scale and add in the completely clear (not smoked) plates that darkstorm has available like such:

Clear > Smoke > Blue > Green > Amber > Red

I have never used the clear ones but they *must* be a little more visible than smoke simply because smoke filters a tiny bit of the light out.

I have used a couple different flavors of blue, but I hear there's a new blue that people have been getting that's a little darker than it used to be on the Mk2's. But my major point is that smoke colored is definitely brighter than blue.

OK, to answer your questions:
2) color - OHP can print any dang color. I'm assuming the lighter the screen color, the closer the text color will be to the natural greenish color of the VFD. (Remember I'm trying to match the red instrumentation of my dash.)

In a manner of speaking, yes you are correct, the lighter the colour the less influence it will have on the colour of the VFD. However it will also depend on the saturation of the colour as well. I take two print passes with the colour as I find it helps to get nice rich colours. If you want something more subtle then one pass will probably be sufficient. You should have no problem achieving the correct colour to match your dash lighting. You might have to go through a bit of trial & error to get it just right though.

3) Glare - Based mainly on how shiny or matte the top surface of the screen. Some have suggested using 600 grit sandpaper, sandblasting, or some AR coating.

At the moment mine's glossy. I've had a quick look around the web for some aerosol anti-reflective spray and all I could find was this. Unfortunately they don't have an agent here in the UK at the moment but they are working on getting it manufactured here. I haven't tried ordering any so I don't know whether they'd ship it over to me. I've thought about bead blasting (a bit kinder than grit or sandblasting) but haven't actually tried it so I don't really know how it would work out. I think it might make it too matte so you might have to do some gentle polishing to give it a kind of silk finish. I also thought about the possibility of using some of that spray on Glass frosting or some silk finish lacquer.

4) VFD reflection - direct sunlight being reflected by the unlit portions of the VFD display. Problem mainly experienced in sunny California; not ready to move to the UK (althought the customer service is better there, I hear). arrreerrrr, different thread....

I do find that in brightish sunlight it is difficult to read and it seems very dependant on the screen colour. As you've probably seen I have a multicoloured one at the moment and it really depends on how the sunlight hits the screen as to whether it's the darker or the lighter colours that get washed out first. YMMV of course.

Beaker, how do you attach you OHP film? Do you use a clear plastic lens? Does it have a matte finish? Do you mount it outside of inside of the lens? Does Macromedia Freehand work with your Corel 5.0 files?

I mount it instead of the lens. I don't have a colourless one that I can use although I do intend making one and doing some experimentation with blasting etc. I've no idea whether Macromedia Freehand will read the CorelDraw file. Sorry.

Basically just experiment. That's what I did and the results have always been more or less satisfactory. My method(s) are not definitive and I don't pretend that they're as perfect as a professionally manufactured screen but they are more than acceptable (IMHO) and offer the opportunity to get colours that aren't available elsewhere.

I hope you have a go and you are as pleased with the results you achieve as I have been with mine.

it may not be aerosol, but what about something like this?

--dan.

Oh non-glare clear adheer film! Zoinks, djc that's a good idea! So far, maybe the ulitmate would be a laminated combination as follows (from inside to outside):

Beaker's OHP colored film + Darkstorm's clear screen + Dick Blick non-glare clear adheer film

Time for some experimenting. Now where did I put that inkjet printer?? Beaker, thanks for the details!!
--Andrew

A genuine "one way" mirror is impossible to build because it violates the laws of thermodynamics. If you made up a box of "one-way" mirror material which was oriented so more light flows into the box than flows out, then more and more light would flow into the box and build up there. It takes energy to do such a thing. If genuine "one-way" mirrors existed, they would serve as energy sources, and you could use one to build a Perpetual Motion machine.

I could be wrong as I've only had one year of college level physics, but I disagree with this last paragraph. Yes, a one way mirror cannot be created -- but not for this reason. This would not be a perpetual motion machine. First of all, a perfect mirror cannot be created, because if it were, it would have to be perfectly (infinitely) smooth, but on the atomic level such a surface cannot exist. When light hits a mirror, some energy is absorbed by exciting (heating and moving) the atoms of the mirror. Therefore the light would not be perfectly contained in the box.

"It takes energy to do such a thing." Ummm, the light is the energy.

"Light would flow into the box and build up there.” How is this different from put a piece of black paper in the sunlight and watching it heat up? Did I just create energy?

P.S. IANAP

Hmmm... that looks quite interesting. I wonder how 'matte' it is. I think I'll have to go into some art shops around here and see what's available. Thanks .

Hey - no problem. Good luck!! .

I went to an art supply store yesterday and picked up some "acrylic sealer" in a spray can for about $5. It comes in glossy or matte. Last night I test strayed in on some shiny piece of plastic lying around the house; it goes on evenly and it definitely seems to take the shine away. Not sure how it will hold up with wear and tear.

The same art store also carries rolls of similar sticky peel-away, matte finish plastic. I'll pick that up for $10 if the spray doesn't work out.
--Andrew

OK, thanks for letting me know. I'll definitely look out for some at the weekend.