If I were to build a projector, the only way I could do it is if I mounted it to the floor. These things are huge. I would need to use lens shifting to project it up on to the wall. Using a 15 inch panel and the lumenlab s15 lenses, and just building it as a straightshooter, would this be difficult? When lens shifting do you also have to use keystone correction to make a square (actually, well, rectangular) picture?

Lens shifting? You mean a Varifocal triplet? If so, I'd say that you don't have to adjust the keystone... IF you have to, I'd bet it's not a big tweak

Wait for someone who knows more about keystone effect before you start building

A few threads on the subject :

http://www.lumenlab.com/forums/index.php?showtopic=24265

http://www.lumenlab.com/forums/index.php?showtopic=23109

I'm trying to come up with a plan to floor mount the projector and then make it so it projects up onto the wall. Like this:



Will this effect the overall brightness of the image? If so, should I just make it a straight shooter PJ, then aim it up at the wall and keystone it with the front fresnel?

You might want to consider a coffee table design if the projector will be in front of you.

There are several PLOGs that you can check out. Here's a few:

http://www.lumenlab.com/forums/index.php?showtopic=21374

http://www.lumenlab.com/forums/index.php?s...st&p=209461

http://www.lumenlab.com/forums/index.php?showtopic=4752

http://www.lumenlab.com/forums/index.php?showtopic=807

http://www.lumenlab.com/forums/index.php?showtopic=5677

http://www.lumenlab.com/forums/index.php?showtopic=14658

http://www.lumenlab.com/forums/index.php?showtopic=9871

You get the idea.

Thanks for the examples Quasi_Mojo. Those are very good examples of what I'm kinda trying to do. One projector that I really liked was Garfing Sharks's PJ. At first when I saw it I was like "where's the projector?, oh that IS the projector!". This type of design built into a storage bench would be good for me because the projector would be sitting next to me on the floor.

I think I should still raise the PJ up a little because if I don't keystoning will have to be major and if it's on the floor people's feet might get in the way.

What would really be awesome woul be if I could do a vertical PJ, but I don't think that's possible for me right now because this is my first projector.

I can understand that a vertical build may seem daunting.

However, you can contact TESCORP via his external website and purchase plans for his V-15 series projector. If you've got the money, you can even have him build the enclosure for you.

He mentioned that with a 15" setup, you would get a 100" diagonal image with the triplet 12 feet from the screen. Moving the projector closer to the screen would make the image larger, naturally.

We are unable to provide a link to his site due to conflicts of interest.
But you can find his site by doing a Google search using the search terms: +tescorp +"v-15" +projector +plans

I think from here I will continue with my plan to just do a straight shooter, but instead of using lens shifting I'll just make it striaght on, aim the projector at the wall upwards and use keystone correction. Kind of like benchun's yellow treasure. This is how my setup would be. I have a small space kind of like his. I will be placing my PJ next to my couch and aim it up towards the wall. This will make it much easier for me to build. The only thing I will have to do is raise it up a bit. I may build a platform for this.

ONE QUESTION:

If I get a 15" monitor, like this:
http://www.walmart.com/catalog/product.do?product_id=7754347

Will the fact that it is widescreen, NOT fullscreen (it has a 16:10 aspect ratio), affect it's being able to be used with the s15 lenses?

It looks like your LCD diagonal measurement is 15.4" widescreen display - With a 1280x800 resolution and a 16:10 aspect ratio with 262K color support

Hmmm... Plug your numbers (LCD diagonal, front fresnel FL, triplet FL, distance to screen and choose split setup) into the FocalCalc and show us what you get.

With the S15 components, you might find that you'll have the projector blocking your view. The keystoning only allows for a certain degree of adjustment - something like 15 - 20 degrees.

Before I start my build (because I'm low on money) what piece of the projector should I buy first? I'm buying parts one at a time. I plan to buy the lcd first. I found a 15" widescreen panel that is 720p (shown above in the link).

I see what you are saying now. With the s15 lens it will throw a 170 inch image. TOO BIG!!! I'll have to move it up, which will make the projector be in the way. The only other thing I can do it get a lens with a longer throw. The pro lens would be great, but I'm not about to spend $200 on a lens. Any ideas?

You could probably get a deal on a Beseler lens on eBay. I, personally, don't have any experience with them, but a search here will give you more reading material. With that type of triplet, you'll have to go with a front fresnel with a longer FL.

Could you post an image of your FocalCalc results?

I cant seem to get the Focal Calc results to post. I think I will just use the s15 lenses and just put the projector on the floor in front of me. Will this work?

To do a screen capture of the FocalCalc, open the program up, with it as the active screen press ALT + Print Screen. This will copy the current window to your clipboard. From there, you can open up MS Paint (or any other paint program) and paste the image there. Save it as a .gif image and you should be able to upload that image to the Forum. Forgive me if you already know this.

Or, you could post the various measurements needed (mentioned above) here and I'll do it.

The panel is 15.4 inches diagonally (16:10 aspect ratio), the triplet focal length is 320mm, the distance from projector to wall was originally 12 feet, but now it will probably be shortened to something of probably 8 feet, and those are the only measurements I pretty much now for now. The projecter would most likely be on the floor. I don't know if I can do enough keystone correction because it might be too steep of an angle.

Well... it looks as if the S15 fresnels will not cover a 15.4 LCD.
The fresnel dimensions are: W - 319mm x H - 252.4mm
The LCD dimensions are most likely: W - 344.0mm x H - 222.0mm (Estimates of 1280x800 LCD found here)

You'll either have to find a way to scale down the size of the image on the LCD or go Pro (or find a cheap Beseler).

No, the largest panel that the standard fresnels will cover is a 4:3 15".

For WXGA, the 12.1" panels would be recommended.

Also, for my own experiments, I was unsatisfied with keystone correction over about 10 degrees. It gets signifigantly worse after that, but your eyes will determine your own limits there.

this is getting so frickin complicated....

I'll use the pro fresnels and the s15 triplet.

Will this work???

Sorry, no.
The front fresnel would have to have a FL that's about the same FL as the triplet.

You might want to consider a monitor like this one.
It's a 4:3 and the resolution is only 1024 x 768, but you could use the S15 setup. You might be able to find a less expensive 14" elsewhere, though.

I REALLY wanted to use the walmart panel cuz it was 720p in a 15" panel, but alas, I'm just going to look for a normal 15" panel and use the s15 kit. It will cost me less anyway.

As SupraGuy mentioned above, the best option currently for 720p using the S15 setup would be the 12.1 panel. On the plus side, that panel is one of the most transmissive and needs no Anti-Glare stripped from it.

I'm on a really tight budget, Im gonna go with a standard 15 inch lcd monitor, 4:3.

You can still use the 15.4" .

You will need the standard S15 triplet and the 220mm and 330mm fresnels from www.3dlens.com. Parts # A395a and A395b.

how do you know that will fit?

Cause it's a question I've answered quite a few times on here.

Ok, I trust you.

But anyway, i found out user sdubb will be buying some panels for cheap and I might be able to get one for $35 so is it better for me to just save money and get the normal 15" panel or spend $130 for the 720p?

720p will look a lot better and less screendoor effect.

I'd go for the 720p.

It will fit the s15 lenses because of the fact that it's widescreen, so it will actually be almost the same width as a 4:3 15" monitor but a shorter height, right?

jonjandran, as kevinkrg is going to be placing the projector on the floor, in front of the seating area (about 8 feet from triplet to screen, as I understand), will he be able to keystone the projector enough using the S15 triplet and fresnels from 3Dlens?

Yeah I just measured from the wall, it will be about 8 feet, but at this point i'd really like it to be on the floor, and then I'll use a piece of wood or something to raise up the front. Just hoping I can keystone it. I'd like the image to be in the middle of the wall, but I dont know if this is possible.