...starting over..... (read here: http://www.lumenlab.com/forums/index.php?s...p;st=200&#) I have a ballast(hard to break one of those!) and a strand reflector and a 6x16 precondenser.... a new light meter is the first thing..then decisions, decisions! which triplet, which lcd, which light system......hmmm....
more later!

Anyway... no pics yet, hey can you use those disposable camera to take screenshots with? Projecting at about 7 foot diagonal (4x6 foot screen) ....
and it was a long journey..... the total doesn't include all the false starts, rebuilding
it twice, a failed psone projector(page magnifiers a copy lens) that ended up getting fried etc.... but I figure that was just learning materials since I hadn't built anything in probably 20 years! ...... was built with a drill, a coping saw and a 2$ jig saw from a garage sale...and really all you need is a drill and a coping saw and a couple of screwdrivers....
WORDS OF ADVICE... for your first PJ, measure 47 times, cut once...well, ok, more like cut 2-3 times, but you get the idea ...... and stick to a successful LL plan(hassman,standard box(mine), punisher whatever..... then AFTER your wife/GF/SO sees that you're not totally insane...then you can screw with it ;-) .....
MAKE FRESNEL SLED AND LCD SLED ..... trust me....!

PJ is connected to my pc, using media player and the ATI multimedia center right now(ATI All in wonder 7500, I'm cheap...), about to install Media Portal to make the whole HTPC thing happen ....

Misc comments:
Brightness .. I know a lot of people would say 250W isn't great but honestly I've
been pretty impressed with how bright it is ..... my bulb is about 14000 mean lumens and While I am thinking of upgrading to the 400W pulse start venture, I can't imagine what it would look like twice as bright
true I'm only projecting a 7 foot diagonal(BO cloth) but still , pretty nice picture!

Pixo LCD .... it pays to memorize all the compatible monitors and haunt ebay... not the best screen(350):1 CR, 25-30 ms response, one small FFC issue(mayeb a 6-10 pin FFC, but it only covers a tiny corner of the screen and really only dims it a little, I'll fix that someday ;-) but for 40$(including shipping) not bad atall!

Cubicized HTPC on the drawing board ....
Now that it works comes Phase 2 ....

picture a glossy black cube , 24" in every direction( "oooh...shiney...").... at the press of a button one corner of the cube rises slowly and majestically (to the strains of Also Sprach Zarathustra ;-) ... at the press of another button a light shines from the from the eye of the cyclopean column and we are transported to a long ago and far away galaxy...

so yeah... I'm a gonna stick my PC in a box with a verticalized projector mounted on drawer slides and a motor to push the pj up to a reasonable height to project from .... and ther should only be one power cord coming from the cube .... sometimes women relly have a thing against 47 cords hanging out all over..sigh... any suggestions? ideas? sympathy?

Great story, if you dont have a digital cam you can have your film transfered to a disc and get some pics on that way. really like to see some pics.

yeah, will probably do that when I start the Cube Mark I .... right now I can't wait to get home to watch movies.... and try to figure out autocad... I did learn it helps immensely to draw draw and draw again till its burned in your brain..... and then of course you change it at thle last minute because you forgot one inty little detail..... originally I was going to take the pc to pieces and install them into the cube but I don't know much about intereference RF wise so may keep the pc in its metal box ... but I may extend the dvd drives cables and attach that to the front of the cube and so its accessible, with wireless internet and wireless mouse and keyboard(stored in the cube I hope) it should have great WAF ..... got the casters so it can roll around...though I may put it off for a couple paychecks and buy a rotozip first... my fresnel sled is pitiful ... ;-)
now what would be cool is to mod some blue lights in the cube and use some transparent smoked acrylic for the cube walls...

When I built mine, I think that in the end, the enclosure was the most expensive thing, and I started with a 48X96" sheet of 3/4" MDF in the garage.

Well, I suppose it matters that I "had to" buy a bunch of tools to make the enclosure.

All in all, though, nice material list. The $40 eBay LCD saves a lot of cash.

For photography... A cheap digital camera won't cut it. Most likely a disposable film camera won't do the job either. If you do want to try a disposable camera get one with 800 ISO film. If you've got a shot at getting a good picture, it'll be with fast film. I'd use at least that with my SLR, and it's got a much better lens for light gathering than the tiny little thing in a disposable. Holding the camera still enough will be tricky, because it'll still need a relatively long exposure. Having it flat on a hard surface will be a must. I wouldn't hold out high hopes for the disposable camera, nor for a cheap point 'n shoot.

If you have a camera with adjustable settings, you'd want the widest possible aperature (low F-stop) to get the shortest esposure time possible. Use a tripod, or at least a hard surface, and use the self-timer so that you're not touching the camera when it goes off. This should produce the best images. Keep in mind that any unevenness in lighting will be exaggerated. The longer the exposure time, the greater the exaggeration. While this is good for enhancing contrast in the shot, it will definitely start to show dimness in the corners.

Most film development places will do images on CD-ROM, which will (usually) be in .jpg format so they can be uploaded.

thanks for the phot info.... maybe I'll see if I can borrow someones.... mmmm..yeah, I have a big box of scrap wood now, but on the other hand I'm really good at using a jigsaw and cutting a semi straight line now! most of the suts I had done at the depot, made things so much easier and they did a pretty accurate job too..... the only thing not so good about the LCD is that once in a while the power light won't come on when I flip the switch so I have to turn it off and on a few times and poof! it works fine..very odd, all connections seem to be good and solid....

I seem to have developed a bad case of "Roxus Meterus" - the insatiable desire to measure and quantify ;-)...just got a light meter in! expecting a new lcd next week and decided to get a light meter.. your basic low end one...the same as you see on ebay for 8.99 with 24.00 shipping... anyway with polarizers on both sides of the LCD and with the LCD off, projecting a 1 square meter surface my first set of measurements were(heading on a diagonal to the corener form the center) : 40,24,12 or about 25 lumens ..pretty low! but.... I ended up stripping the polarizers off BOTH sides of my LCD a couple of weeks ago... was only supposed to be one side ala the extreme mods forums...but I get kind of fumblefingered and had a "stripper" accident... and not the good kind ;-) anyway I had some cheap squares of polarizers from Surplus shed and have been playing around with them but my pj has been moved around and rebuilt since I actually used it and I am going to attempt a haasman style box this next week... so it will be interesting to see how the figures change...I plan to do the 9 point series of measurements someone suggested when the new lcd gets here .... all kinds of ways I can think of... just fresnels and triplet(no lcd at all) then add the lcd to the mix, first off and then with a all white screen, then maybe see if I can figure out how many lumens I am actually hitting the lcd with (with and without the rear fresnel, and try split and unsplit)...any suggestions would be great!

well, I haven't gotten anything measured yet, I spent the weekend attempting to build a haas_man style case(well, its kinda roundey shaped anyway ;-) ... don't have a router so I'm just screwing on the top and bottom..hoping to put the light and fresnels in tonight or tomorrow and testing the lumenage(I just like typing that ;-) with no lcd in , then I may put my non-polarized pixo lcd in there just to see what the transmissiveness without polars is..getting a couple of lcds this week , both ran me about 35-40$ on ebay, one is FPD1530 (thanks to JZONE for the great stripping guide and measurements) the other is a hyundai panel from a daewoo lcd(17" so I fudged on the haas_man box size so I could try that in the box too, using standard fresnels but I figure I can run it in 1280 x768 and only lose a tad off the picture) all assuming I can get them working ... then on to the AG stripping of both ! a busy DIY week indeed...

PS: the "monolith" will have to wait I think till I get the pro lens and fresnels.... this will be the 3rd pj I've built(sorry no pics - the first 2 are unfortunately deceased...gone before their time ;-) ... wanted to get something done before the holidays so I can show off to my wifes sister and husband and the mother in law ;-)

well, I got the fpd1530 and of course just loking at the back of the monitor I can tell its not the same as JZONEs 1530(mine is an LG Phillips LM150X05 from around 2001, his looks like an LM150x08 I think)..sigh.... but I got it down to the backlight in 6 screws and 10 minutes.... then the fun began....little tiny screws that I think were superglued in too! tried every screwdriver I could think of and then posted a thread for help, got some great suggestions ... anyway the upshot is:
I ended up using a couple of different methods, upon closer inspection what looked to be metal that a couple of screws were in looked really thin so I tried to pry it up and it turned out to be the consistency of really really heavy aluminum foil(tougher than that but it gives you the idea) so I managed to "tear" it off with pliers, a couple of other screws I managed to get out by using the tip of a hole boring drill bit, that worked for a couple but the tip got a little bent...then as I was looking at it, I saw that 2 more were just screwed into plastic so I drilled them out from the side till the screw threads were visible and pried them out ...it was a pice of cake after that and the monitor had no ffc issues! one bottom circuit board and one side one....now I have to figure out how to mount the side one(about 1.5-2" total from the side of the lcd..anybody know of any good plogs for that?)..anyway you'll be glad to know I hooked it up this morning and it works great! I was one happy(and surprised guy(I'd , uh, kind of drilled into the side of one circuit board ;-)
so it looks like time to mount the bulb and fresnels into the case (I think I'll keep the ballast external) whilst I contemplate how to mount the lcd and circuit boards(the lcd has an onboard power supply...very nicely put together I must say, much easier it looks like to mount than the pixo, which I hope to get polarizers for sometime....

and having followed the AG stripping thread since the beginning(which is why I'm not using the pixo right now ;-) this panel has AG on both sides just like the PIXO which was also form 2001... I think that must have been common then, a thinner coat of AG on both sides and then for some reason they switched to a thicker coat just on the front.... just my theory though... but I'll wait till I get some measurements done before I attempt to strip the anti-glare off this one....

got the bulb/reflector mounted last night with a minimal amount of adjustment available, the bulb /reflector/mogul base is mounted to a small board (4" square) with the 2 3" bolts in the mogulbase coming out of the bottom, then a hole in the side of the box and then the screws go thru another thin board and the whole deal is bolted with a couple of nuts , right now I can adjust only about an inch horizontally or vertically, no room to go mmmm...widthwise? I mean into the box further or less further unless I get longer bolts, then I can add a couple more nuts and adjust how far into the box I can go, giving me all 3 dimensions adjustment, its not pretty but it works and you can adjust up and down from outside the box..hmmm I guess if I used washers and a really good spring I could adjust the in/out from outside also..like this
there is a 2x2" hole in the case wall(the brown), the green is the spring, black is the bolts, the magenta is the thin piece of wood on the outside of the case, a bit bigger then the 2x2 hole in the case so it seals the case, by loosening the two nuts(you'd have to hold the bolts so the spring doesn't boing! the bulb/mount into the other side of the case;-) you can go up,down left (away from the rear fresnel) right and in/out..not very high tech but it works and is pretty easy to implement, as long as the "cover" board is about twice(?) the size of the hole in the case wall, the air won't mess up your air flow...and being able to do it from the outside with the lid on made it pretty easy to tweak the brightness and eveness of the image... and I always wondered about adjusting in and out
if that would help... plus like I said, its 2 squares of wood and a couple of drilled holes, even I could do that ;-)

also I siliconed the lcd to the plastic frame that sits in the metal frame (..that sits in the haas that mikyd built...;-) so now I have to design the lcd/fresnel holder, I figure cutting grooves in a 3" wide, 3/4" piece of wood for the sides and a board attached to both on the bottom that can also hold the circuit boards, holes drilled into the grooves where I can place tiny dowels to hold the fresnels and lcd and adjust them up and down, the metal frame of the lcd is about 1/4" wider than the rear fresnel so its groove will have to be deeper than the fresnels...fun fun fun!

Let there be Light! I got the seperate power/switch box built last night, I basically cut my old pj in half and boxed the rear end in where the ballast/12v power supply and switches were and extended the wires up to the new case (the whole thing is sitting on an old kitchen cart with a lower shelf where the power sits , with the pj sitting on top of the cart) ...always a little nervous when I switch the ballast on after rewiring even though I check it like 47 times but the fans and bulb came on !
the lcd seems pretty solidly siliconed to the plastic frame though I may run a really small bead around the edge if I think I can avoid getting any on the viewable area of the lcd and the plastic/lcd fits nice and snug into the metal frame.
The fresnels are wrapped in saran wrap right now to keep dust and fingerprints off of them(highly recommended!) so I stuck them in the sled(starting out with unsplit optics till I get all the mounting of the sled figured out then will probably switch to split style) just to play around, seems the standard distance between the triplet and the lcd are meant for a > 7 foot diagonal and seeing as how my wife likes a 5 foot diagonal best(go figure) I learned in my last pj that the triplet had to be a good 3 inches past the standard to focus at that size so as I was playing it occurred to me that the beam diverges after the focal point of the collector fresnel so by the time it hits the triplet in its new spot it is wider than the triplet so less light gets thru..hmmm... wonder how you'd figure out the percentage difference(assuming I'm thinking correctly, optics kind of confuses me sometimes ;-) so really for optimal brightness at a 5 foot diagonal I'd need a longer fl fresnel ....? if it actually is about 3 inches further for the triplet, than a 400 mm one roughly?(320 mm + another 75mm)..ah well, the point is moot for now anyway, I'm almost back in business!!

well, plugged some fairly egregious light leaks the last couple of days and tweaked the bulb/reflector position, amazing how you can tell when you hit the "sweet spot"... much more eveness and overall brightness.... took some new measurements:

at the first fresnel location I got 16000 lux, very evenly distributed, lux readings only varied by 30 lux from center to corner ....
projected on screen(totally white screen with boxes to indicate where to place he light meter:
16|25|17
21|47|22
11|24|17
the lower left seems lacking .. not sure what to tweak ... so on my 1 square meter screen that works out to 22.2 lumens though it seems much brighter than the 20 lumen avg I got the other night and the corners are brighter, though the center is down..

20 lumens, is there more to the formula to get a lumen rating of the projecter as a whole?

not as far as I know.... a lux (according to the dictionary) is one lumen per square meter...I may be using the terms badly .... but you take the light reading average and the square meters of the projection and divide and thats the "lumens" .... however I'm not sure if my light meter is calibrated to the CIE curve which is what is used to test commercial pjs(someone else just told me that, gadgetsmith I think) but anyway, mostly I just want to compare to other LL pjs if anyone else has light meters.....

stripped the antiglare off one side of the lcd last night, will do the other one today..while the lcd is out I think I'll clean the fresnels and triplet...got some plastic cleaner at home depot that says it is for plexiglass and acrylic .... and will redo all my measurements afterward and finally measure light after the first fresnel and after the 2nd fresnel(unsplit) and then just see whats on the projection with no lcd at all...should give me a good indication of my lcd transmissiveness and then after the lcd is back in I'll retest and see if the ag stripping made any lumen diff....

well, while the firs sides ag stripping went well, (it was the rear(original backlight) side, yesterdays front side ag stripping only worked about halfway...originally started peeling at about 6 hours, had some problems about halfway thru so left it soaking overnight...got a little bit more off but gave it up for today....dried the panel off..odd why one side worked so well and the other one didn't, same exact methodology...wonder if the front side had a different coating on it...originally to my eyes they looked exactly the same...oh well, I'll giv it another shot tonight if it doesn't work I may break out the jasco stripper.... maybe I just need to get a newer panel! ;-) these 4 year old ones have not been good to me.... ah well....maybe I'll start stripping the 17" monitor this weekend and then try to figure out how to turn it on without the button circuit board! ;-)

I'm not surprised to hear an older panel is harder to strip. My 150MP was discontinued a few years ago, so I got it used. I noticed the "glue" on one side seemed a lot harder to get off than the other. It probably gets a little gummier over time. Just make sure you do a good clean up with alcohol and/or lens solution after you manage to get the AG off, otherwise the glue residue might give you "color stains" on your image.

yeah, the rear came off clean as a whistle, it was the "front" of the panel that was tough... you removed the ag from both sides? or the polars?

I only removed the AG from one side (and I think I might have missed most of the TAC layer). The leftover glue/ag residue gives the edges of my image a yellowish tint. I'm going to do another stripping pass on it, and also remove the TAC layer from the other side. I think there's still a lot of performance gain to be had with my panel.

busy weekend, the wife has bronchitis so I was Male Nurse for the weekend ;-) ... but I did get the 17" lcd stripped of its Anti_glare.. now just a minor redesign of the sled and I'll run it in a resolution within a resolution using powerstrip(since I have the standard fresnels)

hmmm.... still need to build the sled for the 17" and new frame for the fresnels.... but I did get some new overhead lights so I can actually see when I cut my hand off ;-) ..boy the new panl is transparent now...ticked that I didn't think to measure its transmissivity before and after ag stripping...but I had a very limited amount of time to work in the lab and decided that stripping was the most efficient use of my time.... also got reflective polarizers yesterday for new light engine testing...... and will see how they work with my other two panels in need of polars.... but going out of town till saturday so nothing till sunday I guess I figure if I could get at most 2 hours down there I could see what the new screen projects like.... ah well...

man I love my wife..got me a table saw for our anniversary...whipped out a new sled for the fresnels and the 17" lcd last night in like an hour last night... not terribly adjustable but for now it works great...have to put a mask on the lcd and setup powerstrip to do the "picture in picture" but went down this morning and goofed around with the triplet, definitley off the prime point(using the front piece from when I had the 15" in, I had set that up not centered in the case because it was easier ;-) and even though the triplet was at least a half inch off where it should be, the projection was definitly brighter and just to my eye, the color seems much richer.... the pj may be brighter since I had to take out the bulb/reflector setup out to extend it further into the case and I noticed that the reflector had moved out of plce by about a half inch ors so, but the way it had done it made it very difficult to see while it was in the pj...upped my hifghest readin at the center of the projection from 58 to 75 lux.... even after masking the lcd it should still be noticeably brighter than before....
when I get back from a few days off I will have the makings for testing a new concept for a light engine that mark came up with... should be interesting, ozstang had some thoughts there too...glad we have people who can theorize.... ;-)
and who knows, I may even get to watch a movie sunday!!!

ok....back in town and managed to get down to the lab...tweaked, cut a new front piece with a niceley centered triplet hole, then spent 30 minutes getting rid of the "spiderwebs" caused by misaligned frenesls ;-) then tweaked bulb again so....
new measurements:

9points.gif:
36|50|29
37|78|41
27|49|34

9points2.gif:
19|18
48|47
77
47|54
17|15

ok...let me get the ol' abacus out...
9points average: 42.3
9points2 average:38

projection size: 36" by 48" = 1728 sq. inches * 645 (square mm per sq. inch) = 1114836 = 1.1 sq. meters
so assuming any relation to reality:
9points.gif = 42 * 1.1 = 46 lumens
9points2.gif = 38 * 1.1 = 41.8 lumens ...
using a 250 W venture bulb(ed28) ikea reflector (14000 mean,mmm...18000 initial lumens)

which doesn't sound like much but its way up from my earlier measurements... I may tweak the placement of the bulb again, this time just to make sure it is in the center - width wise in the box... but I have to say the picture looks pretty darn good, very watchable, focus is much better across the picture.... there is a tad bit of keystoning going on I think the sled is a touch off true vertical and tweaking it by hand I'll screw it down later today...then I promised myself I'd actually watch a movie(figure March of the Penguins would be good for this) and thinking ahead..if I go for the 400 watt ballast and bulb I should be able to get a nice 7 foot diagonal at the same brightness as I have now(twice the lumens meaning I can up the diagonal 50%) must also mention the colors are very nice..not as washed out/muted looking as they were with my original lcd...probably due to the AG stripping? hard to say.... I'll be able to say better when I do a side by side with the tv upstairs...... I remember vividly how dull the colors looked side by side with the tv picture in the pjs earelier incarnation...and I might even have some bad screen shots later and of the box, my daughter loaned me her digital...just an old one megapixel but hey....better than nothing!

just thinking about the new setup, I remembered looking at the lcd in the box last night and thinking that the picture(1024x768 via powerstrip ) looked smaller than on the 15" doh! of course it is.... due to smaller dot pitch in a 17"(.264 vs .297) ...which also explains my observation that the throw looked a bit longer than it used to for the same size projection(not neccesarily a bad thing ;-) so using the dot pitch I am going to try 1152x864 in powerstrip resolution in a resolution, works out to almost exactly the same size as a 15" .... of course the throw will shorten back to normal too..but it should be a tad brighter as more square inches means more lumens gathered... we'll see

just doing some calculations and yes, am curently only using 85 square inches as opposed to standard 15" of 108 square inches.... I thought the mask would be a bigger part of the area of an lcd(unless it is included in the pixel dimensions) but no, my 15" had a "dot pitch" of .297 , multiplied out it comes out almost exactly the viewable area of the screen(per the lcd specs) .... its off a little (like .01 inches) but that may just be due to my using 25.4 mm to the inch, it may actually be different in the decimmals after 4...anyway, I think first I may see waht the throw is like first(hmm... I'll give the focal calclator here a shot) but probably I'll increase the pixel count(assuming powerstrip and windows agree! ;-) , I doubt it will be a straightline increase of 27% increase in lumens since it will be adding an "outer border" so to speak and lumens decrease the further from the center you go(damn pythagorus anyway)...but it may be 10-15% maybe..wonder how I would calculate that! hah, like I could...this is where its nice to be able to just do something when the math is beyond you ;-)
and that should also give me an idea of lumens increase when I get the bigger fresnels so I can use the full 1280x1024 of the 17"

hey, just in case anyone is wondering how I got the 17" into a haasman style case, the only difference is that the inside is 14.5" across(internal width) and I fastened the top and bottom to the outside of the sides rather than routing the groove for them, this lets the lcd mounted in its metal frame sit perfectly in the box, to hold it and the fresnels I took two pieces of 3/4" pine 2.5" in width and the height of the box, and then using the table saw made a groove in each one 1/2" deep x 3/4" wide to hold the lcd in its frame and then screwed on 2 pieces of 1/2" thick,1" wide mdf to the lcd holder wood and put a groove in it about 3/4" from the lcd groove to hold the fresnels..worked like a charm...biggest problem I had was that the fresnels were causing a moire effect since the centers weren't perfectly aligned with each other... to fix this I used the old standby binder clips and just looked at the screen while adjusting the fresnels till there was no lines... took about 3 tries to get it right, could have used a third hand! I read somewhere that seperating the fresnels by a little makes it better also so I may cut another piece of mdf and put 2 seperate grroves for the fresnels.... as long as the condenser(330) is the same distance from the lcd , there shouldn't be any light loss from seperating the 2 fresnels since the first one collimates the light , well, as long as you keep the distance reasonable anyway.... I checked once how the light dropped off with distance after the collimating fresnel and it was negligible within the confines of the pj box...

If there's one thing that I've noticed through my experience in engineering, it is that theoretical calculated values are never the same as the measured values. I say measure it instead of calculate it!

-ZY

and that sounds a lot better than saying I have no idea how to calculate it!

well, I attempted to do an 1152x864 window in powerstrip but not sure if I succeeded, if O did it didn't change the lumenage...but I was in a hurry this morning so I think I may have meesed the settings up, took me 3 tries to get the original 1024 in a 1280 going.... anyway, working on a new concept light engine with reflective polarizers and prismatic filters.... its a long shot but for once I have all the pieces I need (look at the "diffusive light engine" thread)
the more I use the new lcd in the pj the better I like the colors .... now if I could get santa to bring me a 400 watt ballast for xmas can't imagine the pic being twice(or more) as bright!

amazing what reading other plogs will show you...was reading comp_atkins(I think) and he mentioned something about adding some horizontal adjustment to his triplet and its like DOH!...sigh... I can see my triplet is a bit out of postition and figured I'd have to cut a new forntpiece....when I saw his plog it occurred to me I can do the same with the triplet as I did with the bulb/reflector mount..duh...... of course while I'm at it I suppose I should actually mke some kind of focus mechanism probably go with the old box in a box with the box being the size whole front of the pj...hmm....maybe I can put some cloth(BO?) to expand with the out movement(like a camera bellows) and then just a couple of would strips to guide the frontpiece in and out...have an old pc keyboard drawer rail set but I've never been too impressed with its rigidity(they always tend to have too much up and down movement) but I may give it a shot anyway..I did find a site about making your own camera bellows..amazing what people DIY !! I can set the frontpiece distance to be a nice 8' diagonal projection and then I think would need about 4" extension to focus a 5' diagonal(thats from memory) and maybe a little more just for playing around with, with using the entire front of the pj I shouldnt be shutting out too much of the light cone...... or at least, no more than is possible!

adjustment i use.

4 wing nuts, for perfect tweaking.

if you enlarge the holes on the wood mounting plate (brown in my diagram), you can swivel around side to side up and down. using washers and stretched springs (both available at Home Depot), you will be able to fine tune the triplet to the best setting.


good luck



Click to view attachment

good tip, thanks, I'm going to try this this weekend I think that'll be the last adjustability possible except for the in/out of the bulb(I'll probably try springs there too)

well, after playing with new ideas for light engines I put the pj back together to actually watch a movie (new concept eh?) (xmas vacation ...and while playing with the adjustment, even though i had cut some further adjustment into my bulb positioning(so I could move it closer to the rear fresnel) it seemed like I could probably stiull move it closer...and in this thread I found(I think) the calcs for the minimum arc-rear fresnel distance:
http://www.lumenlab.com/forums/index.php?s...20&#entry108136

unless I calced wrong it looks like I can take it down to 160mm from arc to fresnel... which is probably prety close to what I thought I could last night... (remember, right now, using a powerstripped 1024x768 window on a 17" monitor, I have essentially a 13.3 " lcd and a 60" projection)..so..jigsaw to the rescue! after that I'll take some more measurements and see if I'm closer to IronGeckos calculated values...

so now, with christmas(and hopefully new tools!) coming and the end of the (current) testing/design phase I need to calculate all my various distances, including what I need to do when I get the proper sized fresnels from 3dlens for a 17" with the standard 80mm triplet... but now at least I have calculations that at least give me the outer bounds of all my adjustments,,well, at least until Brain gets the new lamps in..I figure it'll be a race to get the "final" pj built before I have to start on the new one!!!

in the intel design subforum i posted my bulb movement adjustment. i would recommend using that too. cutting the 17" 3dlens fresnels is fun! i did it on a table saw. what made it extra difficult was that the center line of my triplet/bulb isnt the center line of the LCD, its off by about a half inch (no way around it in my design), so i had to keep track of where i cut what from. All worked out great though

what kind of blade did you use in the table saw? the first time I tried to cut a fresnel was a page magnifier from staples and using a jigsaw ... not a good choice ...... yeah I just read that thread.... happy with my vertical (though I'm going to cut that down to maybe 1/2 inch in the final pj) and horizontal(need most of that adjustment because of wildly varying sizes of diagonals)....did you find the umm...in/out adjustment handy? measured my bulb and its pretty close to center(well, as close as I can accurately measure anyway)..ps... your adjuster is way nicer looking than mine !

just a quick note that the wife enjoyed watching the movie the other night, she did say it could be a bit brighter though so I figure with a 400 watt smaller arc lamp like brain is talking about it should be very pleasing to her.... now if I could figure out some screen arrangement thats better, still using an old(I mean really old) portable movie screen(the kind your grandpa used with a bad viewing cone and she was sitting off to the side...looking at some kind of pull down screen if I can figure a way to keep it taut.... have thought of maybe pvc pipes to tension it, not terribly elegant though..or maybe some of those collapsible tent poles .... I evan thought od making a rigid screen that is flat against the ceiling and then swung into place with a simple rope and pully arrangement(suitably disguised though)

some new measurements after I added about another 1/2-3/4 inch to the arc-fresnel distance(closer)

at 1024X768

21|38|29
36|68|42
21|48|40

3'x4' projection, 70" throw = 38.1 * 1.1(m2) = 42 lumens

at 1152x864

21|40|26
35|76|40
21|52|42 = 39.2 *1.1 = 43 lumens

still more adjustments to come, I think the in/out of the bulb needs to be adjusted...

well, the holidays are over finally, with a family medical situation, my wife is staying with her mother to help her for a few days so I decided to quit "perfecting" the pj for a few days at least and actually watch some things on it.... even though one side is definitly dimmer than the other(the in/out of the bulb I think) , still I'm watching some stuff she's not fond of(oh get your mind out of the gutter catching up on this season of LOST, downloaded them in HDTV and boy, even with not the bets eveness of brightness, its amazing...wonder how they film that show, the picture is just incredibly good, great,rich colors.... I suppose it could be because its HDTV? plus no commercials, I'm up to episode 3.... watched some standard TV too....man its bad resolution ! but watcheable anyway, the video card(ATI 7500 AIW) must line double it or scale it up or something, not as bad as you would think it would be.... can't wait for the new LL bulb/ballast to come in, can't imagine what it would be like twice(or more) as bright as it is now!

Pictures?

I'll see if I can post some screen shots and a shot of the box as I'm using it now.... looking at it I can almost understand why the wife said: " wow, thats a great picture..you're not going to put that in the living room are you?"

which I almost died laughing when I saw almost word for word that same quote in someones' tag line here... womens taste can be universal I guess , and she was glad to see she wasn't the only one that felt that way (I knew I shouldn't have shown her that ....)

Thats why I spent a little time and designed something "interesting". I know she will take the size of it, if it looks interesting and also does the job. Im pretty sure she would not go for a box, no matter how nice it looked.

Wife Approval Factor is everything in this hobby ( If your married, that is...)

yeah, I gues I originally didn't take that into consideration... this time around I'm going for a victorian/hg wells time machine/steamer trunk look, black leather,studs, brass etc (she collects old trunks) depending on my woodworking skills ... personally I thought a black shiny cube would be pretty cool(think the monolith from 2001) but that one is going by the wayside too.... I wonder if a jacobs ladder on it might be going too far though(the "young frankenstein" look ) ....

Yep. I had to put some brass in and tone down the look a little. It will probably lean more to the "Jules Verne" side than the "Diamond Age" look. I just didnt have the time to do my idea for the curves. Maybe when things calm down.

My original Idea was to do a Sleestak Pylon!

well, I remember the old "Time Machine" movie(50s?) and I remember just thinking that was the coolest looking thing.... I've actually been using the pj the last few days watching this seasons "Lost" while the wife is gone.... she'll be back monday so its back down to the lab with the pj, plus I have a couple of new reflectors coming in to try out and I may resurrect the psone project... I figure when the new lamp/ballast comes out I'l do a "final" build for a pj to actually use and then do all my experimentation with my leftover lamps and fresnels and reflectors and the couple of 15" lcds I have laying around from my polarizer?AG stripping days
I'm thinking I may get an actual old steamer trunk for the "production" pj, I think I can put my pc parts in it also so it'll be a one piece unit with just one cord coming from it(the biggest objection she has ;-) and maybe make it a vertical so when not in use it will look like one of her other trunks and when in use just stand it on its end..... and a wireless network and mouse/keyboard...

edit: "land of the lost" ? man I feel old now....

Yep. Land of the Lost. Cheezy and cool!
Dont feel to old. I actually had someone post in my plog that they could not understand how someone who had 17 years of psychology under their belt be called "SamuraiJack"...

Youth is wasted on the youngins....