Ok I've decided for my project I want to use a Xenarc 700v 7" LCD Monitor ( http://www.hometechwonders.com/700v.html ).
[Problems with Solutions]
Need to extend the wire here http://www.talix.com/Pix/Rear_SubPanel_Switches.jpg . It's the brown wire on the left.
A. Extending the Cables
1. http://www.diyaudio.com/forums/show...erpage=15&highlight=extend+cable&pagenumber=1
2. http://www.diyaudio.com/forums/showthread.php?s=&threadid=9800&highlight=extend+cable
[Problems without Solutions]
A. 7" - 8" Fresnel
1. Can I find one and where or are there better solutions?
B. Light Source
1. I want to use about 138 5mm 7000~8000mcd LED's. Don't tell me about cost I can 200 of them for around $60 ( http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2557838264&category=26207 ). I want to know if this will work? Basically I would have them right behind the lcd screen (a little space between).
[Problems with Solutions]
Need to extend the wire here http://www.talix.com/Pix/Rear_SubPanel_Switches.jpg . It's the brown wire on the left.
A. Extending the Cables
1. http://www.diyaudio.com/forums/show...erpage=15&highlight=extend+cable&pagenumber=1
2. http://www.diyaudio.com/forums/showthread.php?s=&threadid=9800&highlight=extend+cable
[Problems without Solutions]
A. 7" - 8" Fresnel
1. Can I find one and where or are there better solutions?
B. Light Source
1. I want to use about 138 5mm 7000~8000mcd LED's. Don't tell me about cost I can 200 of them for around $60 ( http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2557838264&category=26207 ). I want to know if this will work? Basically I would have them right behind the lcd screen (a little space between).
If you had searched you'd see that LED's don't work. They're just not bright enough at the current time. Even the brightest of them would take many more than would be practical to make a decent light source. Best to stick with 150w-250w Metal Halide.
Ehuwiko said:
Yeah that's what I've read, but I would like to know how much light is required to get a decent picture. That and how to convert mcd to lumens. 🙂
The problem is that you'd need so many of them it would just be a big backlight, not a point source light. The light spreads out a lot, it's not focused like other light sources, you generally loose a lot of it. With the brightest ones you'd probably need 400 or more to get a decent light output, considering all the lost light you'd have. 400 LEDs wouldn't fit behind that LCD, and with those ones you'd probably need more. Not to mention it would be really hard to wire all those...
...plus the heat would fry your LCD or something even more expensive (according to Murphy).
One LED = cool
400 LEDS = 400x less cool 😉
One LED = cool
400 LEDS = 400x less cool 😉
To get a decent picture you need a lamp that puts out at least 15,000 lumens. AT LEAST! Second if your going to go through the trouble of extending a flex cable... make it worth your while. You wont be happy with a 7" 800 x 480 screen. Blown up it's not going to look nearly as good as a 15" XGA panel would.
Bottom line is your plan (except for the LED's) would work... but you would be another person who gives up on DIY projectors because you wont get the results you were expecting.
Bottom line is your plan (except for the LED's) would work... but you would be another person who gives up on DIY projectors because you wont get the results you were expecting.
hi laserline
glad to see other guys interested in compact videoprojectors
are you sure you have to extend the flat cable?
cant you only flip the pcb to 45° from the lcd?
i'm waiting for my lcd and i have no soldering or extension to do with it (hitachi 800*480 7")
for the fresnel i've bought 2 single fresnels lenses with a fl lenght of 33 centimeters each
so 33/2=21,5 fl lenght
for the light ,'i'll try with a "cold" 250w halogen bulb and fans, fans and fans
i don't have a good projection lens for the moment
i make my try with a zeiss 50mm lens
if you want to try your setup without burning your lcd, try this
print a pic on a transparent plastic sheet(epson inkjet sheet for example)
using the same size and resolution than your lcd (use photoshop)
and put it in your setup instead of your lcd
remember you won't have the same light and contrast than with your lcd but it can help and you do not have to manipulate your lcd
maybe this can help youmaybe....not
bye
glad to see other guys interested in compact videoprojectors
are you sure you have to extend the flat cable?
cant you only flip the pcb to 45° from the lcd?
i'm waiting for my lcd and i have no soldering or extension to do with it (hitachi 800*480 7")
for the fresnel i've bought 2 single fresnels lenses with a fl lenght of 33 centimeters each
so 33/2=21,5 fl lenght
for the light ,'i'll try with a "cold" 250w halogen bulb and fans, fans and fans
i don't have a good projection lens for the moment
i make my try with a zeiss 50mm lens
if you want to try your setup without burning your lcd, try this
print a pic on a transparent plastic sheet(epson inkjet sheet for example)
using the same size and resolution than your lcd (use photoshop)
and put it in your setup instead of your lcd
remember you won't have the same light and contrast than with your lcd but it can help and you do not have to manipulate your lcd
maybe this can help youmaybe....not
bye
moi said:
Yeah, I don't see any other way to move the board away from the LCD. I can't move the board away from the LCD 45° without extending the cable.
moi said:
No, right now for me this is all on paper. I don't want to waste any money because I'm really poor 🙁 , so I want to get it right the first or second time.
xenarc specs
contrast 200:1
responce time 30ms
resolution native 800x480
compressed resolution 640x480, 800x600, 1024x768, 1280x1024,1600x1280
some may think that 640x480 is crap, well 800x480 is the same but wider, some are also too picky, and some are happy with the basic means, i have 320x240 right now upgrading to 800x600 native, why the upgrade u may ask? well the simple fact is not cos of resolution and a crappy picture but the fact i have a limited space for a nice image im going 2 resolutions up, my 320x240 looks just as good as a 1024x768 at 15ft seating distance of a sceen size of 80" so i sujest those who want to pic at resolutions should also consider the persons seating arangement, some may think im bullshitting but this is the the truth, the further u sit the better the image even for a xga lcd, but if u can only aford a lower resolution make sure u have a decant sitting space away from the screen, and 800x640 is a fine resolution for a seating space of 8-10ft and at 80" sceen size. I ask people not to pic because this forum is like a war zone and manny have different opinions, if your opinion is of a strong nature and not a level headed one then shut up! consider the seating arangments first and screen size, find out the facts before u post. Just out of interest what will be your seating arangment and the screen size u plan to project?
Trev
Not trying to start a war but please people grow up
contrast 200:1
responce time 30ms
resolution native 800x480
compressed resolution 640x480, 800x600, 1024x768, 1280x1024,1600x1280
some may think that 640x480 is crap, well 800x480 is the same but wider, some are also too picky, and some are happy with the basic means, i have 320x240 right now upgrading to 800x600 native, why the upgrade u may ask? well the simple fact is not cos of resolution and a crappy picture but the fact i have a limited space for a nice image im going 2 resolutions up, my 320x240 looks just as good as a 1024x768 at 15ft seating distance of a sceen size of 80" so i sujest those who want to pic at resolutions should also consider the persons seating arangement, some may think im bullshitting but this is the the truth, the further u sit the better the image even for a xga lcd, but if u can only aford a lower resolution make sure u have a decant sitting space away from the screen, and 800x640 is a fine resolution for a seating space of 8-10ft and at 80" sceen size. I ask people not to pic because this forum is like a war zone and manny have different opinions, if your opinion is of a strong nature and not a level headed one then shut up! consider the seating arangments first and screen size, find out the facts before u post. Just out of interest what will be your seating arangment and the screen size u plan to project?
Trev
Not trying to start a war but please people grow up
jcbk
heya there u might aswell say im specialised in the small screen projectors, others who know me and talk to me out of the forum know what i have been doing, ya sure i havnt posted any new projects but i dont have much time the last months but anyway any more than 15000lm through a 7inch lcd with be too much and wash out the image with too much light, whites will get too white and blacks are just not there, 14000lm is the absolute tops for a small screen as the light is more captured eficiently and is more intense at these angles, for the compact projector people dont use ohp condensers use rectangular pcx lenses
for those who dont know,pcx stands for plano convex, it is a lens that is flat on one side and curved on the other, they are used widley in pro projectors as condensers as any optical engineer will tell u that these lenses serve as a condenser and a magnifier thus giving u a brighter more colour corected condensed beam of light.
Trev
heya there u might aswell say im specialised in the small screen projectors, others who know me and talk to me out of the forum know what i have been doing, ya sure i havnt posted any new projects but i dont have much time the last months but anyway any more than 15000lm through a 7inch lcd with be too much and wash out the image with too much light, whites will get too white and blacks are just not there, 14000lm is the absolute tops for a small screen as the light is more captured eficiently and is more intense at these angles, for the compact projector people dont use ohp condensers use rectangular pcx lenses
for those who dont know,pcx stands for plano convex, it is a lens that is flat on one side and curved on the other, they are used widley in pro projectors as condensers as any optical engineer will tell u that these lenses serve as a condenser and a magnifier thus giving u a brighter more colour corected condensed beam of light.
Trev
I agree with ace_3000. He has made several light boxes that incorporate these designs and he gets 500 ANSI lumens from a 2500LM halogen. He uses a 320 by 240 lcd but when sitting against the wall with the furnature it looks like HDTV quality . We are currently making a curved screen that will enhance lumen output and create an IMAX feel. We soon will have 16:9 LCD's that will enhance the HD feel. So what ace_3000 is saying ain't ********. Just use correct optics and everything will turn out. We are also creating a lense that will project an imax style of picture. We are also creating a zoom lense.
🙂 well, trev and mike, things are growing , i see
i hope your work is on a good way.
laserline, i'm not sure it'll be cheaper to build your setup with a 15" panel, even so ,do you really want to have this "big thing " in your home?
as trev says, consider the place in the room you want to watch movies, mine is 7*6 meters , so i just need a 150 centimeters base screen , i must seat in the middle of the room because of the rear speakers.
and don't forget, take your time to build it, i've not built my lens for the moment,waiting for trev,as he knows what setup i have ,i'm sure he can find the best lens i need.
you can begin with a cheap lcd with a low res, then change only the lcd in few months.
or..continue to watch lil'tv
bye
i hope your work is on a good way.
laserline, i'm not sure it'll be cheaper to build your setup with a 15" panel, even so ,do you really want to have this "big thing " in your home?
as trev says, consider the place in the room you want to watch movies, mine is 7*6 meters , so i just need a 150 centimeters base screen , i must seat in the middle of the room because of the rear speakers.
and don't forget, take your time to build it, i've not built my lens for the moment,waiting for trev,as he knows what setup i have ,i'm sure he can find the best lens i need.
you can begin with a cheap lcd with a low res, then change only the lcd in few months.
or..continue to watch lil'tv
bye
what must be the curve of the screen?
its diameter and th distance from its top to its bottom?
do you have a plan?
bye
its diameter and th distance from its top to its bottom?
do you have a plan?
bye
Well it's great to see this crowd in this thread. Ace_3000 you totally right about that whole war thing i hate it. It's the same thing that happened before YHW was here and everyone said you couldn't build one with an LCD monitor and yet YWH showed us all. And Moi I definiately want to keep my projector as small as possible and I want to be able to take it to a friends place and hook it up, so size in my case does matter to me. 🙂 Thanks for the motivation guys!
laserline
im not sure if u saw my projector at all in the diy projector II thread but here are some links to it in the thread
http://www.diyaudio.com/forums/show...5&pagenumber=89
http://www.diyaudio.com/forums/show...5&pagenumber=90
http://www.diyaudio.com/forums/show...5&pagenumber=93
http://www.diyaudio.com/forums/show...5&pagenumber=94
i thought i actually posted more pics than that and those pics are abit outdated as now i have made a new smaller and brighter light box for it, anyway hope it helps u with ideas on it i also have plans for it too but soon will be modified for the xenarc 16:9 screen and a better cooling system. If u have msn messenger and want more pics drop me a line the screen name is ace3000_1@hotmail.com
Trev
im not sure if u saw my projector at all in the diy projector II thread but here are some links to it in the thread
http://www.diyaudio.com/forums/show...5&pagenumber=89
http://www.diyaudio.com/forums/show...5&pagenumber=90
http://www.diyaudio.com/forums/show...5&pagenumber=93
http://www.diyaudio.com/forums/show...5&pagenumber=94
i thought i actually posted more pics than that and those pics are abit outdated as now i have made a new smaller and brighter light box for it, anyway hope it helps u with ideas on it i also have plans for it too but soon will be modified for the xenarc 16:9 screen and a better cooling system. If u have msn messenger and want more pics drop me a line the screen name is ace3000_1@hotmail.com
Trev
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