Thanks for the reply. I have two more questions:
1. How are you placing the metal halid bulb? Horizontal or vertical that is in hanging or upright ? or perpendicular to the plane of LCD ? The close up of the lamp assy posted by srini is confusing. In my preliminary trials I am keeping the lamp hanging.
2. What is the correct side of the fresnels to be used ?. Placing the grooved side of both fresnels facing the LCD gives me better picture.
1. How are you placing the metal halid bulb? Horizontal or vertical that is in hanging or upright ? or perpendicular to the plane of LCD ? The close up of the lamp assy posted by srini is confusing. In my preliminary trials I am keeping the lamp hanging.
2. What is the correct side of the fresnels to be used ?. Placing the grooved side of both fresnels facing the LCD gives me better picture.
srini's pic is very clear to understand,check it.I am just a newbie so not placed bulb yet.
I am planning to mount bulb just like srini,horizontal,perpendiculer to light throw.persons have made many type of bulb mount.hori,vert hang,vert upright.ABOUT perpendiculer to the plane of lcd...I do not know,but it will not create the point light source we want to achieve.led arrays like hertz sir design is faced towards lcd plane,that is perpendi to the plane of lcd,but bulb I dont know.
about matching the triplet,fresnel,lcd centre point with light centre wood piece adjustments have to be done.
yes grooved side of both fresnel faces lcd in split(face each other in unsplit).parallel light is alwys on the groove side of positive fl fresnel(the fresnels we use in diy pj)
btw what are your pj specs.
I am planning to mount bulb just like srini,horizontal,perpendiculer to light throw.persons have made many type of bulb mount.hori,vert hang,vert upright.ABOUT perpendiculer to the plane of lcd...I do not know,but it will not create the point light source we want to achieve.led arrays like hertz sir design is faced towards lcd plane,that is perpendi to the plane of lcd,but bulb I dont know.about matching the triplet,fresnel,lcd centre point with light centre wood piece adjustments have to be done.
yes grooved side of both fresnel faces lcd in split(face each other in unsplit).parallel light is alwys on the groove side of positive fl fresnel(the fresnels we use in diy pj)
btw what are your pj specs.
srini's pic is very clear to understand,check it.I am just a newbie so not placed bulb yet.
I now have tried all positions and found that horizontal positioning is the best. I even tried perpendicular to the LCD position with a reflector from the headlight of an ambassador car. Although the light is strong, it gives a blank ( black) spot in the middle. ( I even tried it with a 35W CFL. With CFL, there is no blank spot). So I settled with the horizontal position.
btw what are your pj specs.
panel from 10 inch super LCD portable TV. ( resolution not known but the projected test images are not that bad). This is the best 10 inch panel I could found. I wish to upgrade to a better (HD) panel with HDMI / DVI connection later when one is available.
Single glass lens from an old OHD F=33 cm
Fresnel again from old OHD. I split the joined fresnel using a haxsaw blade. One F=22 cm near the light and the other F = 36 cm near the LCD before the lens.
250W MH osram lamp
5mm Acrilic sheet seperator. I am yet to order a tempered glass.
Details and pics will be posted later as the set up is not final yet. I am yet to find a suitable reflector. For the time being the projected image ( about 80 inch diagonal) lack some light. May be due to absence of reflector.
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My projected image lacks some light. The reasons may be lack of a proper reflector and / or shabby wall.
On the wall side, how can I improve the pic quality ? Repainting the wall with some kind of paint / refinishing with wall putty etc can improve the image ?
The 250 W MH it self can get very hot. I do not want to upgrade the light to 400W.
On the wall side, how can I improve the pic quality ? Repainting the wall with some kind of paint / refinishing with wall putty etc can improve the image ?
The 250 W MH it self can get very hot. I do not want to upgrade the light to 400W.
pic quality depends on screen,native res of lcd,light output,very very importantly(what we forget very often) is source.I mean what are u actually playing.do that source file have that much res?and remember u are playing via av cable(that yellow cable),so very high res is also not needed.upto the cables capacity u have to play to understand.original dvds are cool.
about the diy pj reflector,its hard to find locally.I am saving money as I decided to buy everything (except light engine) from hertz sir.
.I mean what are u actually playing.do that source file have that much res?and remember u are playing via av cable(that yellow cable),so very high res is also not needed.upto the cables capacity u have to play to understand.original dvds are cool.about the diy pj reflector,its hard to find locally.I am saving money
as I decided to buy everything (except light engine) from hertz sir.pic quality depends on screen,native res of lcd,light output,very very importantly(what we forget very often) is source
about the diy pj reflector,its hard to find locally.I am saving money
Yes. I am aware of all these factors. As far as content is concerned most of it can be full HD, either through full HD STB or full HD media player. But the LCD accepts only AV in and the resolution is unknown.
I am also in the look out for a better LCD.
BTW, how far can I improve the present set up by way of reflector and screen. As I asked earlier, how far we can improve the screen?.
ok.in that case you can re-finish the wall by plaster of paris,and painting a matte white colour.that will cost you around 2500/- with the labour charge etc..may be more.otherwise you can search blackout cloth in good furnishing showrooms,like skipper.cost 2k.someone in india even tried thermocol sheets/advertising big boards with white paint,very cheap option.
and as I said local reflectors wont do much.still u can search electrical wholesale market and hunt for reflectors if u get any suitable size.
and the yellow cable of tatasky hd box OR media player really sucks,they do not carry signals upto the value the yellow cable is supposed to carry.first I tested in a 40 inch tv from original dvd disc from branded dvd player.quality was really good,then I have tested ,connecting av in,,hdmi for comparison from tatasky and from media player.even vga sucks from those media players.I have tested with upto 15GB single movie file.not that much big file required really.
for good lcd I think china e bay,or hertz sir(within even 4k lcd module available both places) is the source.otherwise if u can get 13 inch hdmi tv in your area.chances very less.
and as I said local reflectors wont do much.still u can search electrical wholesale market and hunt for reflectors if u get any suitable size.
and the yellow cable of tatasky hd box OR media player really sucks,they do not carry signals upto the value the yellow cable is supposed to carry.first I tested in a 40 inch tv from original dvd disc from branded dvd player.quality was really good,then I have tested ,connecting av in,,hdmi for comparison from tatasky and from media player.even vga sucks from those media players.I have tested with upto 15GB single movie file.not that much big file required really.
for good lcd I think china e bay,or hertz sir(within even 4k lcd module available both places) is the source.otherwise if u can get 13 inch hdmi tv in your area.chances very less.
This is because they may carry only 576i (PAL) or 480i (NTSC) signals. True HD out may be available only over HDMI.
Any brand name / model no please ......... To the best of my knowledge lowest size available with HDMI is only 22 inch.
to devdas --pls check ur gmail.
to god--13 inch hdmi tv is available in curtis,coby, seiki, unknown chinese brands.but the problem is, it has hdmi,but native res of lcd is not really good as they claim in every brand,plus we do not know if they are diy friendly or not.and cost is also not low if you buy them internationally.for smaller lcd optimum solution is(obvoiusly in my opinion) to buy kit from as I mentioned.hertz sir or china e bay.
to god--13 inch hdmi tv is available in curtis,coby, seiki, unknown chinese brands.but the problem is, it has hdmi,but native res of lcd is not really good as they claim in every brand,plus we do not know if they are diy friendly or not.and cost is also not low if you buy them internationally.for smaller lcd optimum solution is(obvoiusly in my opinion) to buy kit from as I mentioned.hertz sir or china e bay.
jay no way of taking my lcd outside box,( i am not going to risk of tearing the ffc cable).let the box be big..Now my box is 13' from screen.i get picture in size of 10' x 10'.but what i do is keep VLC player window in center of projected image.advantage is the brightness is even on all corners,secondly i am watching from 11' distance.
Best try a used projector ,But it is second hand not worth for money if it goes busted. Replacement of lamp may cost from 7k onwards.
After investing nearly 17K for this projector i have learnt some key points to do for a new builder.
they are
* Go for a 10" panel and lesser not 15" .( advantage is smaller box,no distance problem from screen,easy handling ,not bulky)
* new non printed flex banner is best for screen.(very cheap Rs 500 - Rs 750,no painting problem,no hotspot or bright reflection in one spot)
* get ur parts from Hertz sir in philphines.he has a vast knowledge and experiance.(lcd,reflector,all lens)
* HD content or HD content converted to DVD quality is the only BEST to watch in this projector.NO CAM,TC prints or even DVDrip.
* go for HD capable LCD only for good long lasting happy viewing.(u will fed up if u watch dvdrip,tc or cam rips)
*go for DC fans since they have less and lessest noise level.(strictly no AC fans horrible noise even if u have one fan running)
Ur wall should be a distemper painted one ,0% reflective.dont use enamel or emulsion.I used emulsion it was horrible.shifted to distemper,picture is good.
for a projected image content must be hd to hd converted to DVD.
go for a professional painter for doing a putty finished wall and distemper coat.i tried but takes long time ,u have to make two putty coats to do properly,sand with 180 and finally 320 size emery paper.then apply distemper two coats in interval of 7 hrs.(colour is base white)
downloading some hd content.will post this week end.No heat issues.i run 2 fans one inlet for cooling lcd and one exhaust.i have still not closed the top cover.(i think i will not do it in future. i have small gap in top covers side ) overall no heat issues for 250W.i watched 3 hrs continuosly.
Hello to all my fellow DIYers. It's been real long since I logged in last which was June 2008. I had built a projector back in 2007, which is very much functional till date. you can catch a glimpse of the pictures at macxpages dot tripod dot com.
Well, now I need some help from the experienced masters here. The projector that I had built was perfect for our room in bangalore. with 15ft of viewing distance, the long throw lens worked just fine. however, we have now moved in to a new house at pune, and the modern design of the flat is no good for projections. there's no straight distance where we can project. hence, i am trying to reduce the distance to say around 8ft. i would like to know if this can be achieved by using a short-throw triplets. also, is there a source from where i can order one? earlier i had ordered from lensel optics, but seems they have closed down. any help in this regards is highly anticipated.
Thank you.
Well, now I need some help from the experienced masters here. The projector that I had built was perfect for our room in bangalore. with 15ft of viewing distance, the long throw lens worked just fine. however, we have now moved in to a new house at pune, and the modern design of the flat is no good for projections. there's no straight distance where we can project. hence, i am trying to reduce the distance to say around 8ft. i would like to know if this can be achieved by using a short-throw triplets. also, is there a source from where i can order one? earlier i had ordered from lensel optics, but seems they have closed down. any help in this regards is highly anticipated.
Thank you.
is n't the flex sheets are reflective ? How much gain did you have after using flex ?. can you post samples ?
I did used white plastic sheet available from rexine stores ( of the kind we are using on beds used by babies. But it was highly reflective.
But my panel is not HD or HD ready. It seems that I am using the same panel / (TV) as used by the member maks001 as in the post just above. The quality is watchable on feeding from a HD STB.
try optics and allied engineering in bangalore for short throw lens.u have to change the front frsnel to 330 fl.u will get this also from them.
great job srini
srini thank you for so much sharing.specially the tips for new builders.I was little confused what to use ac fan or dc fan.now I am going to use dc fan as per ur recomendation.because in some serious scenes the noise can spoil the mood.
and yes I completely agree with u.let the box big.its better to have a bigger box than damaging those ribbon cable.
to maks--what are the results right now if u play from 8 ft?
are they very small in diagnal say about 60inch?
but one thing, in a already made set up keeping other things constant just changing the triplet---will it work?will it need some esy tweak or difficult ones.u have to consult with some expert.
BTW lensel still sells 317mm triplet--3k total
optics allied also sells 317 triplet--2.4k total.
if u live in bangalore,u can directly go to optics offices and simply buy it.much less price then.something like 1800/-
I have quatation from both places.
srini thank you for so much sharing.specially the tips for new builders.I was little confused what to use ac fan or dc fan.now I am going to use dc fan as per ur recomendation.because in some serious scenes the noise can spoil the mood
.and yes I completely agree with u.let the box big.its better to have a bigger box than damaging those ribbon cable.
to maks--what are the results right now if u play from 8 ft?
are they very small in diagnal say about 60inch?
but one thing, in a already made set up keeping other things constant just changing the triplet---will it work?will it need some esy tweak or difficult ones.u have to consult with some expert.
BTW lensel still sells 317mm triplet--3k total
optics allied also sells 317 triplet--2.4k total.
if u live in bangalore,u can directly go to optics offices and simply buy it.much less price then.something like 1800/-
I have quatation from both places.
flex banner will be not that shiny.
my panel is 1024 x 800 res.but i download hd rip and convert it to dvd pal using rer software.now i have hd quality movie file.
The source file should be BR rip or 720p for good quality watching.never watch tc rip or cam ,u will get frustrated.
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srini just a query.
why do u convert ur downloaded file into dvd pal.
u can run the downloaded file directly by vlc from ur pc/laptop.because file transformation always degrade quality and why will u use ur time for transformation?
6GB movie files are good enough to watch.off course higher GB files are awsome.but they take lonnnnnnnnnggg time to be downloaded.
.why do u convert ur downloaded file into dvd pal
.u can run the downloaded file directly by vlc from ur pc/laptop.because file transformation always degrade quality and why will u use ur time for transformation?
6GB movie files are good enough to watch.off course higher GB files are awsome.but they take lonnnnnnnnnggg
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