This is my first post here, im work with Diy projector in a some months...

Well my project actually is a Psone 5" screen and Hqi 150w...

Have make the mods of Bright and rouge, but I not have used the maximus power of my lamp, because more ilumination i lost, and i have study a form to reduce the lost of light...

see the pic:


My reflector has a big and how in the pic i lost good amount of ligth in this old model, then I have changed...

Then i can win more quality:



But I like do this mod:



But like know If i can have problems, per example shadonws of light or other problems types...

Thanks all repply!
PS: Pls dont see to my bad english and bad paints
Regards Janio

Janio,
Very nice. I believe this design is called a "light tunnel" ... it is something at the back of my mind, that one day I wanted to experiment with. Would it be possible to post some photos of the inside of your box ? How is the heat at the LCD using this design ? From what i've read, the temperatures can really jump up at the LCD using a light tunnel.

cheers,
gs

Quite some time ago I posted a question regarding whether anyone had done work with a light tunnel. My only question is how do we reconcile this apparent succesful use when set against the continual backdrop of discussions regarding the absolute necessity of collimating the light emanating from the lamp prior to it reaching the rear fresnel??? Based purely on the two photos presented Janio's gains are tremendous and not incremental or negligible in the slightest. Is it because it's a relatively small panel?

well despite optics 101,, if those are a true representation,, well I would give a test rig a go,,,, I have the golaith unit built for such testing,,

grrrrrr, defies,,,, but what is the real black thru to white like,, scale wise is what is needed to be known,,, and that is a split,, config too the field fres sees the virtual image of panel which is being fluoresced (best way to describe it), is the only answer I could muster

one thing I have noted with most commecial units is that an empty black screen does have a luminosity to it, and very noticable during letterbox presentation...

I have always gone on about off axis light causing loss of contrast thru field luminosity,, umm forgotten correct term for moment,,,

heheh maybe this is what we need to get a brighter image,,, heheh

lets call it pre ignition of panel, primed for real collimated light to the triplet out to screen,,,, hmmmmmm interesting concept,,,

at a quick guess I would say that if it works it would only work with a split setup,,,, would cause you to have to change all digital settings and panel settings to offset the luminous panel,,,, hmmmm this gets quiet intriguing,,,,


oh no no no,,, not another antiglare syndrome again,,, noooooooo,,,

hmmmmmm being a smaller panel means less angle in tunnel,,,

oh well still worth a look see on a 17"

hmmmmm,,, having negative thoughts again,,,,,, working theory thru mind,,,,,,

off axis light,,on axis,, polarisation,, colour filters polarisers angels (at slit level) mixed in brew, etc etc etc,,,,

remember term now,, field illumination,, cause a milky effect to anything that should be dark (black),,,

see "+ EDIT" button

You've got quite a nerve trying to stomp on Elken's well-known, infamous, endearing (?) posting style.

Careful you should be young Jedi. Elken only words speak every other...

Between the words, you must hear...hmmm?

actually, I'm wondering if he has actually built the last drawing or if he is asking whether it will work or not, I think the second one(the narrower reflector) is the mod he has made...

Thanks for bringing us back on topic.

Yeah, I think he's asking about doing the last mod as well.


I think you will not have problems with the design using tempered glass if you are experiencing no problems with the other design.

Are you experiencing heating problems at the panel when you do not use tempered glass?

Have you heard of "hot mirrors"?

I can’t see how this would work. I’ve seen it pop up every now and then but it goes against all the theories. The only possible explanation I can think of is he is using a long rear fresnel and a large triplet.

DJ

blue = glasss
purple = FS mirror/ reflective metal
orange = reflected light
yellow = 'cone' from bulb + original reflector

The light tunnel itself collimates the light (makes it more parallel) and makes it homogenous (no hot spots). Then you wouldn't need the fresnel before the lcd. Isn't the purpose of the rear fresnel to take the light cone from the lamp and collimate it so the light is going straight through the LCD?

Like this light tunnel from 3M...... Vikuiti™ Hollow Light Tunnel .

T.

Agree. The debate - as I view it - has been over how perfectly the light must be collimated though. Kind of like "you can't be a little bit pregnant". I guess it'll just take some pioneers to dabble with this concept to see how it scales with bigger panels?

Edit: DAZZ - go buy a bunch of mirrors and a glass cutter!

already have a bunch of mirrors here ready to go,,,,
ya can see them in pics above copiers remains in my new thread DIY secrets,,

I wuz tryin' to get DAZZ to help you elken!

awww geez

You really gonna give this a try?

absolutely on a serious note

even tho it goes against everything I have said and done,,,, but,,

I have been wringing it thru my brain from every angle,,, and something stupidly, says gotta give it a go,,,, simply because of the observations I have made using a Pro PJ (sony),,, and how luminous the black is,,, maybe just maybe something can made out of it,,,, now bear in mind this is purely based on what the creator of this thread, posted,, (as to it accuracy),,, sounds bit like the SIMUL8R,,,,, itchy and scratchy episode last september,,,, hehehehehehheh Besides I am already a murderer of lappies and other asssorted small lifeforms,,


Special note for DAZ,, and not wiggle harmed, in any way manner or form...

hey if I had my Haas one to modify,, no way,, remeber how big my current protogiant is,, with its gaping chasm, where you can park a mini..,, just perfectly suited for this kinda test,,,

Click to view attachment

long rear fresnel
Click to view attachment


By all means try it, maybe there is something more to it. Perhaps the A/G maybe beneficial to this method?

maybe it raises the luminance up to higher level with all that incorrect light, allowing our real light to do the rest,,,,, thats the best I can figure,,, its all about brightness,,, (refering to that luminios black thingy)

if it does,, then It should look shocking when you have lots of white in pic,, or like in bright desert scenes,,,, you cant really tell with darkish type image,,,

I should be working!!! DAZZ - have you tried it with and without a reflector??? How much diddling have you done with RayTrace??? That is RayTrace eh? Is that with max rays - 99? Looks like fun.

Just spend the next week trying a zillion combinations of flat surfaces combined with a pro-reflector or whatever and you may hit the magic combo.

Raytrace yep. I’ve done a bit of Scottish doodling I mean diddling but I only have the restricted version so I only use it for quick visuals of concepts.
OK just for you here’s one with 99 rays and a reflector.

Click to view attachment

Edit:
Oh and this is with just a point source so using an arc will make the spread a bit worse. There is a relationship between the small end of the tunnel and the distance between the separate diverging points. The smaller you make the tunnel entrance, the smaller the final separation will be.

Funky huh?

Geeez Daz,,, aren't you a bit young to take up basket weaving,,,

neat weaving tho..

ummm you do have a few loose ends too.....

hmmmmm mmmmm I just worked it out,,,,, it a pepe,ism,,

he came here to infuse us all with doubt and mistrust,,,,

and yes the earth is FLAT !!!!!! that is a flat'er'ism


ok now have moved on from ies to ism's no more lappeis trippies ballies lampies ,,,, polarism trippism ballism, lampism,,

antiglarism's etc'ism etc'ism

well it looks like some reflected light from a tunnel would make it to the triplet.. I guess its a viable test for a real projector

daz thats an interesting point,,, you only traced a single point,,, '''lets step into the sandpit and play here'''

if the arc spreads a whole heap of light thru all those voidism's then we have globalism across the panelism,,,, bizarrism,,,

thinks me idea had fluttered in window the idea......

can u do a raytrace for a single point with hyperbolic light tunnel?

Hey guys, I noticed Rox hasn't piped up yet, maybe Janio is Rox's new pseudonym and he's just yanking your chains....

This is ringing bells in my head. There was a similar thread going a while back when we were looking into the vikuiti films and using a 'backlight on steroids' to power it.

well rox needs us to play with,,, heheheheheh

a pepe'ism

This one...

Hi Friend,

Look a old imag from my projector, but the old reflector was so big, then i have replaced it for a minor but no have tested using the "tube of light"


New Reflector:



Results:

Hi Durachko,

In fact the photos im not used the light tunnel, i have only diminishes the size of my reflector, but I have tested 2 models first with the behind part concavous but the image not good focus and other the last with behind part rectus then this pic is from the result, but im studing a form to use more from potential of my lamp, because it is only 150w hqi.

I will make news tests son a possible, no have many time actually

Regards
Janio

Hi Durachko,

In Fact i no have none problem with high temp, in first Fresnel i checked around 38°c but i confess my sistem of cooler is not good, in really im using my 1º project psone screen to learn more about of ligth and its characteristics, because i will bluid other projects with a Hami (2x) and i think in bluind a "compact psone" fresnels lower focus 160mm and maybe lamp of car, but i studing this yet...
I see the win in lumens when my reflector (ligth compartment) have a minor size.

Regards!
Janio

In the last screenshot above it seems strange to me that the human figure appears as only a silhouette and is not "visible" at all. How can that be? I can't recall any similar screenies being posted before.

hes real....


Click to view attachment

Hairy too. My point was is that picture really dim since usually you can see a person standing in a screenie like that without boosting the pic brightness?

yeah I agree,, but you can see traces of pic on him too

Hi friends, I have configured my cam to max appeerture to enter more ligth and my screen is in micron glass sphere, but I guarantee that this photo was not manipulated digitally.

thats ok,, i can see that,,,

But i must say on a very funny note that I love the armpit hair sticking out in shot,,, it made me chuckle,,,

I would think the opposite... The picture is very bright, hence a short exposure time which doesn't allow proper exposure of the image on his skin but does for the white screen.

And no one ever believes me when I say I'm stoopid. Thanks for that insight GS.

If any one else want to try to make a light tunnel. You will need some shinny stuff. I just happen to have a 12" x 22" piece of mirrored aluminum for sale. It is vary shinny about 1/8" thick. Send a PM if you want some.

Click to view attachment

Click to view attachment

The plastic is still on
It's not perfectly flat