Hello everyone. I found this site this morning, and have read about 95% of the posts from the beginning. After trying the 100" tv based projector, I decided that it would be just a little more difficult and, just a little more expensive to build and actual lcd projector. The tv projector actually worked a lot better than i had expected, but the problem lies in the fact that the finished unit could be mistaken for your kitchen refridgerator (it is that big), the image is always a little blurry, the room HAS to be pitch black, and the throw distance with the two lenses i tried was only about 4-8 foot, which means the monstrosity has to sit in the middle of my living room, blocking part of the picture it is projecting.
So I started brainstorming a couple of LCD solutions. My first idea was the old pocket tv and slide projector. I thought about an opaque projector, but speculated the lighting to the face of the lcd would render the same result as trying to use your laptop in direct sunlight. And of course there is the overhead projector and LCD overlay, but very few panels are availible at more than 640 by 480. (i want at least 1024 by 768). I have not tried any of these, insead opting to search for more info first, which led me here. I have gotten a lot of perspective on the backlighting of the LCD from the previous messages on this thread. (as well as the heat side affect). I applaud those of you who are trying the white LEDs, that seems to have a lot of promise, once developed. I think for my solution i will end up going with the Flourex, or whatever it is.
Anyway my point is that i have a design that i would appreciate some feedback on. I think it is a fairly decent setup, but i could be missing something. The link to the image is below. The projector is divided into five sections, by various stages of the optics. The back section is where the backlighting is located (compartment 1). There are 4 flourex lights, 2 each side, pointing to the back of the projector. This light is gathered and reflected by a concave mirror towards a condeser lens. This lens is sealed onto the compartment wall, allowing no air travel. The lens passes the light through a short tube extending through compatment two. Comparment 2 contains the tube and fiberglass insulating material, to shield compartment 3 from the heat of compartment 1. (note the dead air space between compatments 1 and 2, & 2 and 3.) On the wall between 2 and 3 is a reversed condensor connected to the other side of the tube, againg sealed to prevent vapor transition. Here the light is spread onto the back of the lcd. in comparment 4 the light sould be travelling fairly straigt into the fresnal lens located between 4 & 5. from the fresnal, the light travels to a lens (have a barco crt lens) and hopefully out to make a big picture on the big screen.
Thank you for any helpful advice, and keep the ideas flowing...
http://members.aol.com/modeofdecay/lcdprojector.html
So I started brainstorming a couple of LCD solutions. My first idea was the old pocket tv and slide projector. I thought about an opaque projector, but speculated the lighting to the face of the lcd would render the same result as trying to use your laptop in direct sunlight. And of course there is the overhead projector and LCD overlay, but very few panels are availible at more than 640 by 480. (i want at least 1024 by 768). I have not tried any of these, insead opting to search for more info first, which led me here. I have gotten a lot of perspective on the backlighting of the LCD from the previous messages on this thread. (as well as the heat side affect). I applaud those of you who are trying the white LEDs, that seems to have a lot of promise, once developed. I think for my solution i will end up going with the Flourex, or whatever it is.
Anyway my point is that i have a design that i would appreciate some feedback on. I think it is a fairly decent setup, but i could be missing something. The link to the image is below. The projector is divided into five sections, by various stages of the optics. The back section is where the backlighting is located (compartment 1). There are 4 flourex lights, 2 each side, pointing to the back of the projector. This light is gathered and reflected by a concave mirror towards a condeser lens. This lens is sealed onto the compartment wall, allowing no air travel. The lens passes the light through a short tube extending through compatment two. Comparment 2 contains the tube and fiberglass insulating material, to shield compartment 3 from the heat of compartment 1. (note the dead air space between compatments 1 and 2, & 2 and 3.) On the wall between 2 and 3 is a reversed condensor connected to the other side of the tube, againg sealed to prevent vapor transition. Here the light is spread onto the back of the lcd. in comparment 4 the light sould be travelling fairly straigt into the fresnal lens located between 4 & 5. from the fresnal, the light travels to a lens (have a barco crt lens) and hopefully out to make a big picture on the big screen.
Thank you for any helpful advice, and keep the ideas flowing...
http://members.aol.com/modeofdecay/lcdprojector.html
Typed the link wrong in my last post: it is actually
http://members.aol.com/modeofdecay/lcdprojector.html
http://members.aol.com/modeofdecay/lcdprojector.html
Projector design
Tom - sure, no problem!
Ofteend - So it is true that XGA OHP panels are rare, 14" LCD monitors are rarer than 15", which are fairly common. A little cited fact is that the bigger the aperature (or diagonal of the LCD element), the more light goes through to the screen, ya know, for the same amount of light going in.
It would make sense then, that the best choice for an element would be the 15" LCD panel monitor, because they're popular and relatively inexpensive ($300 for a 15" XGA vs $200+ for a 5 to 7" VGA panel)
Unfortunately, the 15" is too wide (at ~12") for most OHP stages.
Also, getting one apart so that the light can shine through, whilst still keeping it operational, is non-trivial. Unless you're lucky...
However, I have posted a source for fresnel lenses which are bigger than the fresnel in the typical OHP; it would make sense that you could construct a unit that would resemble a "fat" OHP, with maybe a 12.5" stage., which would accomodate the 15" LCD panel.
Others have said and shown that the ideal light source is a point source that's as bright as possible. The ELMO projector I have bears this out; it has an ultrabright (50K lumens) metal halide lamp with an arc length of about 1/2". When running, the thing looks like that box with an alien inside with the light shooting out every nook and cranny.
The ideal design appears to be a point source light of infinite brilliance, with a lens in front of it. The lens collumnates the light so that it's going out at a right angle from the lens surface, for all points on the lens surface, with perfectly uniform brilliance of course. This way, the panel is illuminated equally at all pixels.
One of the design difficulties is dealing with the heat. The ELMO has fan forced cooling, with one of two fans evacuating the entire enclosure AND pulling air through this metal chimney structure within which the bulb is located. So that bulb has a steady stream of cool, inlet air going over it at all times. (Plus, it's like having a little space heater that keeps me warm...)
My recipe for a stunning success, is as follows
1. Get the brightest, as in # of lumens, OHP you can find.
2. Get a 14" LCD panel monitor, that comes apart OK
3. Arrange it so that it works with the OHP.
OR
1. (same as above)
2. Get a 15" LCD panel monitor, that comes apart OK
3. Get a bigger fresnel lens, arrange it onto the OHP so that it works - create the "fat" OHP...
4. Arrange the panel LCD so that it works with the "fat" OHP.
Of course, "arrange it so it works" may be non-trivial...as a few others will attest.
I'm lucky enough to have a good XGA panel. Even so, the aperature, hence the light, would probably be doubled by going to a 14" LCD monitor panel. 15", even more! This is very alluring to me, that I'd chance blowing ~$300 to find out if I can make it happen.
To recap -
- point source ultra-bright light, fan forced air cooled.
- fresnel lens to collumnate the light uniformly across a 12.5"X12.5" stage
- 15" panel that you can arrange so the light shines through.
- projection lens.
That should do it, I think!
ZZZZZZzzzzz....
Tom - sure, no problem!
Ofteend - So it is true that XGA OHP panels are rare, 14" LCD monitors are rarer than 15", which are fairly common. A little cited fact is that the bigger the aperature (or diagonal of the LCD element), the more light goes through to the screen, ya know, for the same amount of light going in.
It would make sense then, that the best choice for an element would be the 15" LCD panel monitor, because they're popular and relatively inexpensive ($300 for a 15" XGA vs $200+ for a 5 to 7" VGA panel)
Unfortunately, the 15" is too wide (at ~12") for most OHP stages.
Also, getting one apart so that the light can shine through, whilst still keeping it operational, is non-trivial. Unless you're lucky...
However, I have posted a source for fresnel lenses which are bigger than the fresnel in the typical OHP; it would make sense that you could construct a unit that would resemble a "fat" OHP, with maybe a 12.5" stage., which would accomodate the 15" LCD panel.
Others have said and shown that the ideal light source is a point source that's as bright as possible. The ELMO projector I have bears this out; it has an ultrabright (50K lumens) metal halide lamp with an arc length of about 1/2". When running, the thing looks like that box with an alien inside with the light shooting out every nook and cranny.
The ideal design appears to be a point source light of infinite brilliance, with a lens in front of it. The lens collumnates the light so that it's going out at a right angle from the lens surface, for all points on the lens surface, with perfectly uniform brilliance of course. This way, the panel is illuminated equally at all pixels.
One of the design difficulties is dealing with the heat. The ELMO has fan forced cooling, with one of two fans evacuating the entire enclosure AND pulling air through this metal chimney structure within which the bulb is located. So that bulb has a steady stream of cool, inlet air going over it at all times. (Plus, it's like having a little space heater that keeps me warm...)
My recipe for a stunning success, is as follows
1. Get the brightest, as in # of lumens, OHP you can find.
2. Get a 14" LCD panel monitor, that comes apart OK
3. Arrange it so that it works with the OHP.
OR
1. (same as above)
2. Get a 15" LCD panel monitor, that comes apart OK
3. Get a bigger fresnel lens, arrange it onto the OHP so that it works - create the "fat" OHP...
4. Arrange the panel LCD so that it works with the "fat" OHP.
Of course, "arrange it so it works" may be non-trivial...as a few others will attest.
I'm lucky enough to have a good XGA panel. Even so, the aperature, hence the light, would probably be doubled by going to a 14" LCD monitor panel. 15", even more! This is very alluring to me, that I'd chance blowing ~$300 to find out if I can make it happen.
To recap -
- point source ultra-bright light, fan forced air cooled.
- fresnel lens to collumnate the light uniformly across a 12.5"X12.5" stage
- 15" panel that you can arrange so the light shines through.
- projection lens.
That should do it, I think!
ZZZZZZzzzzz....
jjasniew What is the model # of your elmo projector?
Thanks! Any links on the web of your OHP?
Also I have a question regarding metal halide bulbs. Does someone sell a Lamp like fixture for a metal halide bulb? The problem is i dont know how to wire so I want a pre-made fixture ready to get a bulb screwed in and plugged in to a socket. Thanks!
Thanks! Any links on the web of your OHP?
Also I have a question regarding metal halide bulbs. Does someone sell a Lamp like fixture for a metal halide bulb? The problem is i dont know how to wire so I want a pre-made fixture ready to get a bulb screwed in and plugged in to a socket. Thanks!
Soldering of ribbon cables
Hi,
I had to change my plans somewhat. In order to move the PCB of my 14" monitor out of the path of light I was going to resolder one 45-pin flexcable connection and one 10-pin flexcable connection with longer cables in between. I started on the 45-pin cable and came to the conclusion that for me it is highly unlikely that after completion there would be no adjacent pins with accidental connections between them. It was just a littlebit too tiny and too close together, even with micro-soldering iron and magnifying glass. I think I've read someone did this with a defective Nview panel, though? So maybe you just need to be really experienced.
Now I changed my setup, so that there no longer is the need to elongate the 45-pin connector. The 10-pin connector still has to be elongated and there is no way around this. Luckily on both sides, the display and PCB that is, there are soldering points close to the connectors for each pin of the cable. They are not much bigger, but they are further apart and that does the trick. On the display part the soldering is completed and seems very well done (not tooting my own horn, just telling you it can be done
) I have taken pictures, but they have to be developed. Yes, that is that old non digital technology our ancestors used...
I have a question for you americans: How big exactly are the normal OHP-fresnel lenses in your country? Here in Germany--and I think all over Europe--the are exactly 28,5*28,5cm with "rounded corners". This leads to the fact that my 14" tft (I think 14" tfts are actually 14,1") does not fit on to the fresnel lens completely. There is about one centimeter lost on each side. The overscan gets worse with growing distance between the tft and the fresnel due to the path of light.
jjasniew: Sorry, I can not find the adress you posted concerning the bigger fresnel lenses. Could you repost it, please?
That's it for now
g!zmo
Hi,
I had to change my plans somewhat. In order to move the PCB of my 14" monitor out of the path of light I was going to resolder one 45-pin flexcable connection and one 10-pin flexcable connection with longer cables in between. I started on the 45-pin cable and came to the conclusion that for me it is highly unlikely that after completion there would be no adjacent pins with accidental connections between them. It was just a littlebit too tiny and too close together, even with micro-soldering iron and magnifying glass. I think I've read someone did this with a defective Nview panel, though? So maybe you just need to be really experienced.
Now I changed my setup, so that there no longer is the need to elongate the 45-pin connector. The 10-pin connector still has to be elongated and there is no way around this. Luckily on both sides, the display and PCB that is, there are soldering points close to the connectors for each pin of the cable. They are not much bigger, but they are further apart and that does the trick. On the display part the soldering is completed and seems very well done (not tooting my own horn, just telling you it can be done
) I have taken pictures, but they have to be developed. Yes, that is that old non digital technology our ancestors used...I have a question for you americans: How big exactly are the normal OHP-fresnel lenses in your country? Here in Germany--and I think all over Europe--the are exactly 28,5*28,5cm with "rounded corners". This leads to the fact that my 14" tft (I think 14" tfts are actually 14,1") does not fit on to the fresnel lens completely. There is about one centimeter lost on each side. The overscan gets worse with growing distance between the tft and the fresnel due to the path of light.
jjasniew: Sorry, I can not find the adress you posted concerning the bigger fresnel lenses. Could you repost it, please?
That's it for now
g!zmo
lokost:
Yes, certainly. Between the lamps and power supplies, there will be heat. I am planning on using several high output computer fans, heatsinks where possible. I am hoping that by physically insulating the lighting from the LCD, I can reduce the amount of heat transfered to the lcd, allowing quieter, less powerful fans to run. Given the lower temp of flourescent based lamps, this could make a fairly quiet operation.
jjasniew:
As far as using OHP, sure that is the quickest, easiest way to get the results I want, but I still run into one of the main issues i had with a TV based system: Size. The room I plan on using this thing in is not tiny, but it is my living room. Granted one wall is dominated by electronics already, but the other 3 i would prefer to leave to more traditional decorating. So small size and aesthetics are important in my final solution. Thank you for the advice, and if all else fails, I will prob. go that route. (I really want a projector!!).
Yes, certainly. Between the lamps and power supplies, there will be heat. I am planning on using several high output computer fans, heatsinks where possible. I am hoping that by physically insulating the lighting from the LCD, I can reduce the amount of heat transfered to the lcd, allowing quieter, less powerful fans to run. Given the lower temp of flourescent based lamps, this could make a fairly quiet operation.
jjasniew:
As far as using OHP, sure that is the quickest, easiest way to get the results I want, but I still run into one of the main issues i had with a TV based system: Size. The room I plan on using this thing in is not tiny, but it is my living room. Granted one wall is dominated by electronics already, but the other 3 i would prefer to leave to more traditional decorating. So small size and aesthetics are important in my final solution. Thank you for the advice, and if all else fails, I will prob. go that route. (I really want a projector!!).
I ran across this on Ebay:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=1712032092
A light valve projector currently at $203 (5 hours left), though it does not power up. Could be a steal for someone who can fiqure out whats wong with the 220 volt monster. The thing looks almost as big as a pallet.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=1712032092
A light valve projector currently at $203 (5 hours left), though it does not power up. Could be a steal for someone who can fiqure out whats wong with the 220 volt monster. The thing looks almost as big as a pallet.
frankbatzen:
There's no standard in the fresnel lens sizes in OHPs. I've myself have had three different OHP:s all having different sized fresnels.
And now when I got to fresnels, you people might or might not(probably not) remember me whining about my fresnel in my diy-setup not taking the heat was put on it. Well my current OHP fresnel gets many times hotter and it takes it just fine. So either the fresnels have differences in the amount of the heat they stand or the "yellowing" effect is because something else as I recall some one lectured about, UV? But from the OHP I stole my bulb to the diy-thing there was no UV-filter, some sort of glass thing but that was with the bulb in the DIY thing too.
I bought a DVD-encoder card but I don't have too much to comment on it. The decoding is somewhat better. What I really wanted was to get it working with SBlive 5.1 which I have but it doesn't as it outputs audio only with cables and I don't have SPDIF input in the card. The card is some piece of **** and I wanted Creative Encore card but the shopper didn't have it. Although I'm not sure if it is doable even with that card.
I'm done for now.
There's no standard in the fresnel lens sizes in OHPs. I've myself have had three different OHP:s all having different sized fresnels.
And now when I got to fresnels, you people might or might not(probably not) remember me whining about my fresnel in my diy-setup not taking the heat was put on it. Well my current OHP fresnel gets many times hotter and it takes it just fine. So either the fresnels have differences in the amount of the heat they stand or the "yellowing" effect is because something else as I recall some one lectured about, UV? But from the OHP I stole my bulb to the diy-thing there was no UV-filter, some sort of glass thing but that was with the bulb in the DIY thing too.
I bought a DVD-encoder card but I don't have too much to comment on it. The decoding is somewhat better. What I really wanted was to get it working with SBlive 5.1 which I have but it doesn't as it outputs audio only with cables and I don't have SPDIF input in the card. The card is some piece of **** and I wanted Creative Encore card but the shopper didn't have it. Although I'm not sure if it is doable even with that card.
I'm done for now.
Bitch:
Hi, thanks for the reply.
I am sure that in Germany all OHP-fresnels do have the same size due to crazy industry norms. Do you remember what size your fresnels were?
Btw, I am spending so much more time on the housing and cosmetic work than on the technical aspects. That really is the most time-consuming part, next to gathering information.
Hi, thanks for the reply.
I am sure that in Germany all OHP-fresnels do have the same size due to crazy industry norms. Do you remember what size your fresnels were?
Btw, I am spending so much more time on the housing and cosmetic work than on the technical aspects. That really is the most time-consuming part, next to gathering information.
Flex Cable Soldering
Ok, I stumbled across this link just before. What it is, is a PCB that connects to those horrible flex ribbon cables associated with LCDs, and adapts it to a row of header pins. So basically if someone had a cheap display that they couldn’t use for their projector because they couldn’t relocate the controller board, then you’d buy one of these converters/adaptors, hook a length of say IDE cable (those hard drive cables) then solder it to the main controller PCB (which usually have large connection/testing pads, which are easily soldered to). They also have (apparently) extension cables for the flex cables also available. And their prices seem very reasonable (17.00 Euro), the only problem (for me) would be getting them here to Australia…
I stole this from their site, it shows what i'm talking about
Hope that helps someone, I know it certainly helped me.
Shane.
Ok, I stumbled across this link just before. What it is, is a PCB that connects to those horrible flex ribbon cables associated with LCDs, and adapts it to a row of header pins. So basically if someone had a cheap display that they couldn’t use for their projector because they couldn’t relocate the controller board, then you’d buy one of these converters/adaptors, hook a length of say IDE cable (those hard drive cables) then solder it to the main controller PCB (which usually have large connection/testing pads, which are easily soldered to). They also have (apparently) extension cables for the flex cables also available. And their prices seem very reasonable (17.00 Euro), the only problem (for me) would be getting them here to Australia…
I stole this from their site, it shows what i'm talking about
An externally hosted image should be here but it was not working when we last tested it.
Hope that helps someone, I know it certainly helped me.
Shane.
I was wondering if it's possible in the 15" Viewsonic monitor (or any other) to keep the original "back wall" in it, just make a hole to it, size of the LCD itself and maybe put some sort of glass in it or such, this way the thing would be enclosured and safe to move around and stuff. ?
frank: I'll have to say that I don't know the sizes of my fresnels.
frank: I'll have to say that I don't know the sizes of my fresnels.
About image quality....
I have been reading an avsforums user's critique of our project, and according to him, one of the projects biggest hinderances is that light is passed through the LCD at different angles (ie. the outer part of the LCD light path angles in, where as the inner is dead on) and of course LCD's are very sensitive to viewing angles. Not sure how true all of this is, but it did serve to confuse me, when I thought I had this already figured out. I attached a little .bmp file of what I think should be going on in an ideal projector.
Basiclly I don't think the fensel lens be in the way of the lights path AFTER it has stuck the LCD. Somehow I think the fensel will have a poor image quality. Let me know what you think. I guess I'm confused on how OHP work, if it doesn't serve light straight up to and focus light straight from the LCD panel, I got a feeling with a 15in or 17in I will be heading for trouble.
But if LCD's have advanced far enough that there veiwing angle is wide enough, I guess its a mute point...
I have been reading an avsforums user's critique of our project, and according to him, one of the projects biggest hinderances is that light is passed through the LCD at different angles (ie. the outer part of the LCD light path angles in, where as the inner is dead on) and of course LCD's are very sensitive to viewing angles. Not sure how true all of this is, but it did serve to confuse me, when I thought I had this already figured out. I attached a little .bmp file of what I think should be going on in an ideal projector.
Basiclly I don't think the fensel lens be in the way of the lights path AFTER it has stuck the LCD. Somehow I think the fensel will have a poor image quality. Let me know what you think. I guess I'm confused on how OHP work, if it doesn't serve light straight up to and focus light straight from the LCD panel, I got a feeling with a 15in or 17in I will be heading for trouble.
But if LCD's have advanced far enough that there veiwing angle is wide enough, I guess its a mute point...
Attachments
Viewsonic VB50HRTV
Got my unit and played with it extensively last night. The VB50, that is.
I'm fairly dissapointed and wouldnt overwhelmingly reccommend it.
It has one problem which is ridiculous, IMHO. They must have used 4 bits for all the controls, such as "tint" and "contrast", because the only setting that's reasonable is dead center. One bump up; it's too much green, one bump down, too much red. So effectively, you cant adjust these, because the @$^^$ steps are not fine enough. You have to make these adjustments on your display, because they are pretty much useless doing it through the remote control access on the VB50.
The other problem is that it does not work well with my Nview panel. On the CRT, colors look great, match exactly with the TV screen. On the panel, "blue" is this turquoise color and if anything's blue, from sky to someone's backpack - it's that color.
Also, apparently it cant make purple - or any shade of blue that's toward purple for that matter.
Now here's the kicker. The colors coming off my so-called "USB TV", which runs though my PC, are better. It can make purple. The colors on the projected panel image tend to correspond better with the colors on the TV screen. I do not understand; it's almost as if the VB50 knows what it's connected to and says "Oh, 256 colors for you!"
Of course, the colors playing a DVD through the PC are OK - I'm sure I would have noticed that it *sucks* if it did on that channel, and not gone off and posted up screenshots.
Because the colors on the CRT are correct, I'm still going to keep the unit. I'm not yet out of the game when it comes to experimenting with LCD panel monitor and CRT based creations.
Like some things, it's tough finding out after the fact what the nits are. I for sure suggest "try before you buy" with your particular setup, if possible.
IMHO,
Got my unit and played with it extensively last night. The VB50, that is.
I'm fairly dissapointed and wouldnt overwhelmingly reccommend it.
It has one problem which is ridiculous, IMHO. They must have used 4 bits for all the controls, such as "tint" and "contrast", because the only setting that's reasonable is dead center. One bump up; it's too much green, one bump down, too much red. So effectively, you cant adjust these, because the @$^^$ steps are not fine enough. You have to make these adjustments on your display, because they are pretty much useless doing it through the remote control access on the VB50.
The other problem is that it does not work well with my Nview panel. On the CRT, colors look great, match exactly with the TV screen. On the panel, "blue" is this turquoise color and if anything's blue, from sky to someone's backpack - it's that color.
Also, apparently it cant make purple - or any shade of blue that's toward purple for that matter.
Now here's the kicker. The colors coming off my so-called "USB TV", which runs though my PC, are better. It can make purple. The colors on the projected panel image tend to correspond better with the colors on the TV screen. I do not understand; it's almost as if the VB50 knows what it's connected to and says "Oh, 256 colors for you!"
Of course, the colors playing a DVD through the PC are OK - I'm sure I would have noticed that it *sucks* if it did on that channel, and not gone off and posted up screenshots.
Because the colors on the CRT are correct, I'm still going to keep the unit. I'm not yet out of the game when it comes to experimenting with LCD panel monitor and CRT based creations.
Like some things, it's tough finding out after the fact what the nits are. I for sure suggest "try before you buy" with your particular setup, if possible.
IMHO,
More about the 15" viewsonic, Myren.
Could you see the "pixel structure" of the LCD in your projected image badly? In my panel it's quite annoiyng with big image you can clearly see in between of every individual pixel a "space", actually now that I think about it I think there has been talk about this, "pixel spacing" in the lcd specs or such.? Anyway I have read that this "pixel-structure thing" (I don't know the correct word for it in english) is a problem in all LCD projectors. Anyway I'm just thinking since the Viewsonic's resolution is so much higher it shouldn't show up that bad?
Could you see the "pixel structure" of the LCD in your projected image badly? In my panel it's quite annoiyng with big image you can clearly see in between of every individual pixel a "space", actually now that I think about it I think there has been talk about this, "pixel spacing" in the lcd specs or such.? Anyway I have read that this "pixel-structure thing" (I don't know the correct word for it in english) is a problem in all LCD projectors. Anyway I'm just thinking since the Viewsonic's resolution is so much higher it shouldn't show up that bad?
Please post pics!! Picture is worth 1K words!
Seems that a few of you have at least SOMETHING going on, could you please post pics please (of the picture)? In particular I was wondering about what others are also asking about, the screen door effect. How bad is it? Not knowing too much about it, I would imagine that this would be countered by line doubling (I never understood this, for a dvd this would mean 720X480 = 1480 X 960, what lcd is capable of 1480 lines???)
I have a uneasy ( and uninformed..) feeling that in our 'large' lcd displays, there is a significant amount of gap(to us) between the pixels that don't exist on on smaller (used by projectors) lcds of equal resolutions. Don't have any facts on this, so don't flame, just fishing to see if anyone know anything about this ( last poster called this pixel spacing)
Btw, any other place besides edmund optics ($$$ ~$80???) that sells decent quality fensels of large size ( to fit a 15 in LCD panel ~12 by 10) that are heat resistent??
Also on a side note I just bought bought an adjustable focas crt projector lens (atlas), not sure if its usefull for the project or not, just thought that it might be. Anyone one else have it, using it already??
And I am kinda hoing that someone will kindly explain to me how the fensels work in our lcd projector systems... and what a optimal system would look like ....
Seems that a few of you have at least SOMETHING going on, could you please post pics please (of the picture)? In particular I was wondering about what others are also asking about, the screen door effect. How bad is it? Not knowing too much about it, I would imagine that this would be countered by line doubling (I never understood this, for a dvd this would mean 720X480 = 1480 X 960, what lcd is capable of 1480 lines???)
I have a uneasy ( and uninformed..) feeling that in our 'large' lcd displays, there is a significant amount of gap(to us) between the pixels that don't exist on on smaller (used by projectors) lcds of equal resolutions. Don't have any facts on this, so don't flame, just fishing to see if anyone know anything about this ( last poster called this pixel spacing)
Btw, any other place besides edmund optics ($$$ ~$80???) that sells decent quality fensels of large size ( to fit a 15 in LCD panel ~12 by 10) that are heat resistent??
Also on a side note I just bought bought an adjustable focas crt projector lens (atlas), not sure if its usefull for the project or not, just thought that it might be. Anyone one else have it, using it already??
And I am kinda hoing that someone will kindly explain to me how the fensels work in our lcd projector systems... and what a optimal system would look like ....
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