Anyone used a Fresnel Lens with LFS?

[Woz]

Just found this (http://www.rickleephoto.com/rlcoll.htm) on using a fresnel lens with MS Flight Sim. Looks interesting. Wondered if anyone has used one with LFS?

[CrazyICE]

nice...
but what effect does this thing have?
(have not read the whole article)

[ColeusRattus]

IIRC someone is using somehting like this. Just browse the "rigs" thread in the hardware section...

[Woz]

nice...
but what effect does this thing have?
(have not read the whole article)

First effect is that the monitor will look much bigger than it really is :)

Second effect is that your eyes focus at a much further distance, nearer to infinity, than the 20" or so when you are sat in front of a monitor :)

Both huge benefits.

I have been lucky enough to clock up 100's of hours on real full motion flight sims while working as a developer for a flight sim company. They use curved mirrors to similar effect and the difference between looking at the image "projected" than on a screen is huge.

Never use a fresnel though but at $28us its very tempting to give it a try

[NotAnIllusion]

Wow I'd definitely go for this if there was any easy way of setting it up (pre-made or something cuz I'm DIY totally incompetent). O.o

[xaotik]

http://www.lfsforum.net/showthread.php?p=22127#post22127

He's the man to ask I think.

[NotAnIllusion]

Cool, will investig8 into this! :D

Lol let me get this right.. All the mod is is a thin plastic sheet (Fresnel lens) and something to hold it in front of the monitor? Sounds too bloody easy but will give it a go :p

[--==Gogo==--]

Post your results.
If they are positive I will buy a fresnel lense for my 50" TV! ;)

[ColeusRattus]

Post your results.
If they are positive I will buy a fresnel lense for my 50" TV! ;)

Angeber! :razz:

As I plan to buy a 19" TFT screen quite soon, I would just like to ask if the added weight could flip the monitor. If not, I might aswell try to find such a lense :D

[--==Gogo==--]

Angeber! :razz:


Hehe. Wer hat, der hat.

I have to arrange my equipment in front of the TV and make some photos! ;)

[CrazyICE]

do it so GoGo....
du "nasebohrer" :) hehehehe (avatar)

also so ne lense wär wirklich was geiles...
such a lense would be coOL...

can't wait for the results :)

[--==Gogo==--]

do it so GoGo....
du "nasebohrer" :) hehehehe (avatar)



For all the people around the world that don't know the german TV-series "Stromberg": The guy in my avatar is NOT me!! :D

[Bob Smith]

Hmm, very interesting. He doesn't really say how to make and mount the lens enclosure, but I'm sure it's not too difficult to think of something.

Edit: that 3Dlens site is a bit crap, but the F550 is here: http://www.3dlens.com/enter.html?target=Large_Fresnel_Lens.html

[NotAnIllusion]

Does it need a projection surface, or am I actually looking directly into the lens? Once I know this, I'm going ahead & getting one :)

[xaotik]

Anyone remember the movie Brazil?

OT: An excellent movie to say the least - "this is your receipt for your husband... and this is my receipt for your receipt." :)

[B2B@300]

:thumb: Wow I was seriously considering making a home made LCD projector, but having seen this I've changed my mind :scratchch for US$28.50 I think its definately worth a try.. and how about a setup like this with dual screens :smileypul

[Mazz4200]

Word of warning on the Fresnal Lens.

Notice how the site does'nt give you a photo of the image the lens produces.

This thing cant be good for your eyes, (try looking through a pair of binoculars for half an hour), i would guess a packet of headache tablets would also be a wise investment to include in the build costs.

[tristancliffe]

Does it need a projection surface, or am I actually looking directly into the lens? Once I know this, I'm going ahead & getting one :)

You look at the lens (or rather, through it).

[NotAnIllusion]

You look at the lens (or rather, through it).

Ta! :)

[Shotglass]

This thing cant be good for your eyes

id say the exact opposite ... at least if the first link is right the picture is a lot further from your eyes than your monitor which is always a good thing for your eyes

[Cue-Ball]

There are several guys running fresnel lenses with racing sims (not just LFS). Take a look here and you should find plenty of hits:
http://forum.rscnet.org/forumdisplay.php?f=186&page=1&sort=lastpost&order=&pp=40&daysprune=60

[5th Earth]

Does it need a projection surface, or am I actually looking directly into the lens? Once I know this, I'm going ahead & getting one :)

As mentioned in an earlier reply to you, you're looking into the lens. However, given a different focal length the same setup will function as a crude projector. The room will have to be VERY dark and it'll be rather fuzzy since the monitor isn't bright enough and the lens is relatively low quality, but it'll work.

A better option for a cheap projhector might be to find an old overhead transparency projector, steal the lens armature off of it, and use that. Brightness will still be an issue but the image quality will be higher.

[Woz]

OT: An excellent movie to say the least - "this is your receipt for your husband... and this is my receipt for your receipt." :)

Noooooooo. I am going to be humming the music that plays throught the film now for days.

[MadArrow]

I've used them for pc based flight simulators. Words don't do it justice. What it does for depth perception is just amazing. I've used both the small ones and one I took from a big screen tv with my projector shining on it. It also is really cool if you hold it under the sun, melted a hole into the pavement with the big screen lens.

[Mazz4200]

Still, since you can get one set up for about a tenner, it's not really a big risk is it?

I'd do it, but it looks like it'd mean a lot of messing about Blue Peter-style each time I wanted to race. I have a hard enough time as it is getting a comfortable seating position without having to put my face up against a piece of plastic too.


Nah, bit of sticky backed plastic and your laughing !

I'm no optometrist, but these are the kind of things my Granny used to read the newspaper with, and it was fine to use for short periods, but, dunno bout you, sometimes hours fly past when i'm racing, and i can only guess at the eye strain ?
I wear spec's and contact's, and the focal length is really important to give you correct vision, so i guess i'm just a bit concerned for your young eye's

Anyway if anyone does try it i'd be interested to know the results.

I've been toying with the idea of the disasembled TFT screen over an OHP, but getting them cheap aint too easy.

http://www.tomshardware.com/howto/20041113/index.html

[Shotglass]

why are most fresnel lenses i can find double sided with different focal length on both sides and would i have to pry those apart to use them with a standard monitor ?

and does anybody know where to buy one in germany ?

[BlueLine]

Just ordered the f550 lens at 3dlens.com

I'll let you know how it turns out! :pillepall

[NotAnIllusion]

It does indeed work, easy to set up, just gotta make the box for it. Get a good quality, decent size sheet btw. :D

[ScHiZ]

I use a cheapo fresnel lens with my setup and it really is a fantastic way of allowing a higher FOV setting and greater immersion.
after reading some of these links, I'm seriously thinking about getting a couple of those 'high res' F550's and using my old monitor for a dual monitor setup..

Anybody successfully had a radeon 9800pro (or any radeon, I s'pose) running LFS across 2 monitors, or is it only Nvidia cards that can be used this way?

[--==Gogo==--]

anyone post some photos please! ;)

[Frankmd]

http://forum.rscnet.org/showthread.php?t=228229&highlight=fresnel

[Cue-Ball]

Anybody successfully had a radeon 9800pro (or any radeon, I s'pose) running LFS across 2 monitors, or is it only Nvidia cards that can be used this way?
I haven't personally done it since I use a Parhelia, but other people have said that ATI cards will work if you use the Hydravision drivers. LFS needs to see one single surface to work properly and apparently the hydravision stuff allows this.

[ellis_dee]

@schiz: Have a look here...
http://www.lfsforum.net/showthread.php?t=1930
, scroll to the end.

Catalyst Control center does the job with one big surface spanned across 2 monitors, but I tried it, and it wasn't very cool without the fresnel lenses due to the turning. The perspective doesn't feel right like that. Kegetys managed to find a solution, but that was kinda slow.

There was a thread at RSC, I think, with photos showing a rig with two fresnel lenses arranged in a way so that the middle bar wasn#t visible anymore.

big fresnel lenses are sometimes sold as TV magnifiers (TV LUPE in german) for old ppl in specialized shops, prices i have seen were like 40-60 Eur depending on the size.

[ScHiZ]

Thanks guys, will investigate :)
I would post pics of the lens setup but that's been packed away due to an impending house move

[jmkz]

you could just read this thread better:p the link is posted
http://forum.rscnet.org/showthread.php?t=228229&highlight=fresnel

[El Presidente]

These guys sell lens and cabinet in the UK, seems quite good I think will be ordering the lens:

http://www.icetec-uk.com/

[detail]

In that thread the guy sits quite far from the screen, like 70-80 cm.

To have a proper perception of speed in a game, the FOV of the screen in your eyes must be the same as the in-game FOV. We have the in-game FOV bigger than the angle at which we see our screens, that's the sourse of the problem.

If we calculate the real screen's FOV and set this value to the in-game FOV, it would look like a narrow window. It would look a bit like the image that we see in a window of an aircraft sitting in the middle or on the other side. I have 17" and my eyes are in 1 meter from the screen, thus I'd need to set in-game FOV to 18.18°! (=2*arctg0.16)

To have in-game FOV 90° and percept it properly, we'd need to place the monitor in 1/2 of it's width from our eyes . For example, 17" screen has 32 cm useful width => the eyes should be in 16 cm from the screen.

So, what I'd like to have, look at the picture. The same 17" screen, but with such a lens, that would make it look like 1m from the eyes (and the eyes would focus on 1m, not on terrible 16 cm), and consequently it would be like 2m screen. :) Real 90°FOV. :D

Though, with such distances the distance between the eyes affects the view.

[edit] Who is good at physics? What's the dependence between the focal length, the distance between the lens, the eye and the observed object?

[eindewege]

In that thread the guy sits quite far from the screen, like 70-80 cm.

To have a proper perception of speed in a game, the FOV of the screen in your eyes must be the same as the in-game FOV. We have the in-game FOV bigger than the angle at which we see our screens, that's the sourse of the problem.

If we calculate the real screen's FOV and set this value to the in-game FOV, it would look like a narrow window. It would look a bit like the image that we see in a window of an aircraft sitting in the middle or on the other side. I have 17" and my eyes are in 1 meter from the screen, thus I'd need to set in-game FOV to 18.18°! (=2*arctg0.16)

To have in-game FOV 90° and percept it properly, we'd need to place the monitor in 1/2 of it's width from our eyes . For example, 17" screen has 32 cm useful width => the eyes should be in 16 cm from the screen.

So, what I'd like to have, look at the picture. The same 17" screen, but with such a lens, that would make it look like 1m from the eyes (and the eyes would focus on 1m, not on terrible 16 cm), and consequently it would be like 2m screen. :) Real 90°FOV. :D

Though, with such distances the distance between the eyes affects the view.

[edit] Who is good at physics? What's the dependence between the focal length, the distance between the lens, the eye and the observed object?

I think you're very right. When i set the fov to 40 deg. everything feels more realistic, like looking trough a window (only a veeery tiny one :D).

Same effect when setting the fov to 80 deg and putting your nose to the screen.

Im gonna get me a fresnel lens I think....

[detail]

I'm thinking about buying this lens. Wrote a question to the 3dlens (http://3dlens.com/) guys. They sell 300x400mm lens!

[B2B@300]

I'm thinking about buying this lens. Wrote a question to the 3dlens (http://3dlens.com/) guys. They sell 300x400mm lens!

They also sell different focal lenght lens for the same sizes, that maybe a consideration also.. keep us posted on what they say as I'm on the edge of ordering one myself - sounds worthwhile :thumb:

[detail]

All right, I'll post their reply.

According to my calculations, it's possible to get big FOVs with lens that has shoter f. In terms of FOV the big F550 (400 mm) can give only 50-55 FOV comfortable for eyes (about 500 mm distance between the eyes and the virtual picture), while 310x310 lens with f220 can make up to 90° (about 600 mm between the eyes and the virtual picture).The only question is if the distance between the eyes affects the image, because in this case you need to look from only 155 mm. I've asked them about this too.

[detail]

Sorry! We are a lens manufacturer only and we do Not know MSFS2004 and Live for Speed and magnifying factor for the simulator purpose. We have many customers said that the #F550 looks very clear in their simulator application. You can find the messages below from http://www.rickleephoto.com/rlcoll.htm

We do Not have much knowledge about the application, but according to info at http://www.rickleephoto.com/rlcoll.htm the lens can be smaller than the monitor. Our item #A310b with 220mm focal length is not good for simulator use.
This is the result. The is just a sales manager who knows absolutely nothing in optics and doesn't even read my message carefully. It was the second reply, in the first he said "i don't know how to use it with a sim", in the second question to him I wrote "gust tell me what angular size can i obtain". I think he saw the word "angular" for the first time in his life.

Okay, I've managed to figure out everything by myself. Just googled to restore my school knowledge of optics, refigured the formulas and the geometrical method.

I'll write the results later. [edit: nope, the short f isn't good.]

P.S.: "magnifying factor for simulation purpose"... I didn't expect it to be of different kinds. You learn somehing new every day. :D

[avih]

It's simple, short F means MORE magnification, long F means LESS magnification. infinite F means plain transparent glass.

So you can increase the effect by having shorter F (can use bigger FOV etc), while paying with more distortions probably due to practical reasons (imperfections of the lense, distance between the eyes is not zero, for most ppl ;) etc)

as the detailed article says, he found that focal length of 11" = ~ 26cm is the best compromise for him.

[Chaos]

Just ordered the f550 lens at 3dlens.com

I'll let you know how it turns out! :pillepall
same here :thumb:

[detail]

same here :thumb:
Eh, eh, the F550 is not the best one. You don't need a very large screen, neither a very long f. As Avih has written, it is closer to a simple glass. I took more time to consider what I select.

As I've calculated, with f550 you can get about 50° FOV. I think, 80° is obtainable with lens with shorter f. It works fine for just enlarging your screen, but to get an effect described by the aviasimmer, you need different lens.

I did some more calcs, and see that the main thing to consider is the relationship of the f and the width of your screen (if it is only one, with 2 screens no problem to make 90° real FOV). To get 90°, actually you need f to be 1/2 of your screen width or shorter.

thisnameistaken: I think, it's better to analyse the options with geometry, not notionally. I'll make schemes in an hour.

[avih]

I haven't looked through one of those for ages too (since a friend of mine had one which he put infront of the TV where a spectrum was connected ;) ). I wasn't too impressed back then btw, but it might be due to so many factors.

So, I don't have any practical experience, which I think is what counts most.

Theoreticaly speaking though, I'd say that the distance of the lense from the subject (i.e. screen) changes the angular size of the image, which in practice allows us to see more details (bigger image), while the distance of the lense from the eye doesn't change the angular size but does changed the preceived distance of the image. This is just intuition though, and regarding a magnifying glass, without trying to calculate it theoretically as others have done here before.

A fresnel lense might be a bit different from "normal" magnifying glass though since it has one flat side and one curved side, while magnifying glass has 2 curved sides. They might have exactly the same effect though, up to the focal length as a function of the curvness of the lense. Again, I didn't try any calculations.

But again, I do think that practical experience is very important here beyond the theoretical aspect. Eventhough it CAN be calculated, I'm sure that there are practical aspects that aren't calculated usually in ideal cases, such as the fact that the eyes have some distance between them, some common distortions of such lenses (maybe towards the outer sides), etc.

So I'd love to hear some comments when you get and play with it a bit ;)

edit- on that MSFS page someone wrote him that he uses the F55 and he's pretty satisfied with it. I'd say it should be a good buy to start experimenting.

[detail]

Here are my calculations. The original values are for the lens given in the Rick Lee's article (http://www.rickleephoto.com/rlcoll.htm). Measurement unit is mm. I think it's not a problem to input the 2 F550 dimensions - size and focal length.

According to my calculations, 220 mm focal distance is the best for this purpose for 19", 17" and smaller monitors.

Check, if they are right. (note: I had to re-learn this stiff 6 years after I learned it a little bit at school, that time I prefered the geometrical method :))

If the main purpose is FOV (with some restrictions), you may even play with MS Excel solver to optimise it. :D

[edit: here is the geometry. The advantage of the small focal length is larger FOV. Though, hasn't a single meaning and there are other discussable aspects. For example, a disadvantage of a very short focal length is that you have either little depth or big magnification. The best solution is a larger screen. :)]

[edit2] So, I think I'm going to order 2x#401B and 2x#A310b. :) If I don't need some, I'll tell other simmers how cool they are and resell, or will make birthday presents to some friends. :)

[edit 3] Okay, the very last detail to these things. Actually, there are few things that differ. Without taking the size into consideration, there is only a trade-off between the depth and the FOV. Focal length is a decisive parameter here, the longer f.l. is the more depth and the less FOV is. Wider screen allows improving of both values.

[Chaos]

err why is it that if I enter the same value for focal length and the distance of the lens from the monitor I get a division by zero?

[Bob Smith]

err why is it that if I enter the same value for focal length and the distance of the lens from the monitor I get a division by zero?
Because doing that would cause the universe to implode.

(it's because, that equation is essentially: 1 / (1/a - 1/b) ... so if "a" and "b" are equal, you end up trying to solve 1 / 0, which is undefined, hence the implosion of the universe)

[Chaos]

Because doing that would cause the universe to implode.
LOL, nice explanation Bob :thumb:

[detail]

F#@$ing WorldPay (http://worldpay.com) they don't accept debit card payment from Russia! I SPENT 3 FREAKING HOURS FREEZING IN A BUS TO GO TO MY BANK, and this is what I get. @#$%

I order it to the same address as wrtitten in the card registration, my name is everywhere, and I'm suspected in a fraud for geographical reason. Idiots.

[5th Earth]

You know, I thought he chose the f550 because it's the only one they sell with a non-square aspect ratio. It aso has a finer groove pitch than the others, which looks better.

[BlueLine]

My lens arrived today. Picking it up at the post office tomorrow!

[bobvanvliet]

Congrats. Post pics when you're done setting it up! :thumb:

[avih]

:)
/me eagerly waiting ;)

[ZeroDexter]

sounds interesting!
i browsed the web and found quite a few shops that sell tv magnifiers (tv lupen) in germany etc. but I wonder if those work the same?
here's an example:
http://www.lupenshop.de/content/lupenshop.storefront/4386fade01dd9b322740d43f47020666/Product/Variation/1710&2D1

edit: the page says product can't be found but if you click OK you'll see it

will that give me the same effect you're talking about (more depth, etc.)?

(I'm not a friend of mathematics so i skipped reading a couple of posts, sorry if this has been mentioned before)

ZD

[TagForce]

Yes, that's the exact same thing... It's just a Fresnel Lens in front of the TV.

[ZeroDexter]

thanks! ordered :D

[detail]

I Hate Their Payment Rules!

In one page it's written "Send the order to another address", and then they say to me "We can't do this according to the banking rules." Freaking bullshitters... I have to pay them 20 dollars more just to send it through a special agency or through another person.

No, let them go hell, I'll sooner buy it anywhere else.

[Chaos]

The F550 arrived today and all that I can say is :thumbsup:

Effectively it made a 21" monitor out of my 17" for $40 and I can even have the virtual 21" monitor closer than I had the 17" (just over the body of my wheel)...

The only little drawback is that the text close to the edges is harder to read, but that can be cured by moving the lens back a bit making the image smaller...

[avih]

The F550 arrived today and all that I can say is :thumbsup:

Effectively it made a 21" monitor out of my 17" for $40 and I can even have the virtual 21" monitor closer than I had the 17" (just over the body of my wheel)...

The only little drawback is that the text close to the edges is harder to read, but that can be cured by moving the lens back a bit making the image smaller...

hmm.. I must say it's a bit disappointing... what about the depth perception? virtual image size, eye strain etc. Does it have real advantage other than a nice gimic?

[detail]

The F550 arrived today and all that I can say is :thumbsup:

Effectively it made a 21" monitor out of my 17" for $40 and I can even have the virtual 21" monitor closer than I had the 17" (just over the body of my wheel)...

The only little drawback is that the text close to the edges is harder to read, but that can be cured by moving the lens back a bit making the image smaller...
Still solving problems with payment here. What is your monitor size in mm? What is the distance between the screen surface and the lens?

I'm going to buy at DIY Projector Company (http://diyprojectorcompany.com/) such a lens : 395x395 f=330. If it will be too tall, I'll make one dimension smaller with scissors or metal scissors.

BTW, if I put 17" monitor beyond a f330 lens, I will have 70" monitor (1 meter deep inside the lens). :D

I'm writing an article on this topic. The first part, theoretical of course, is almost finished, I will publish it tonight.

[Chaos]

What is your monitor size in mm? What is the distance between the screen surface and the lens?
monitor - 430mm
distance - cca 500mm

[KiDCoDEa]

The F550 arrived today and all that I can say is :thumbsup:

Effectively it made a 21" monitor out of my 17" for $40 and I can even have the virtual 21" monitor closer than I had the 17" (just over the body of my wheel)...

The only little drawback is that the text close to the edges is harder to read, but that can be cured by moving the lens back a bit making the image smaller...
can u plz take photos from where ya eyes are usually looking at lens?

[Chaos]

hmm.. I must say it's a bit disappointing... what about the depth perception? virtual image size, eye strain etc. Does it have real advantage other than a nice gimic?
well i played 2 hours straight now, no probs with eyes or anything... i even set a new pb... the advantage is that you have a larger monitor and you can have it closer to your eyes than a normal screen...

can u plz take photos from where ya eyes are usually looking at lens?
yes... but in about 2 weeks when my brother brings a camera...
I have the black momo and the lens is just above the line of the top that needs to be taken off to tighten the wheel in place...
and the lens-monitor distance is 300mm (in my previous post i only guessed, because father needed to work on the computer...)

[BlueLine]

I've had my lens for about a week now. The effect it creates is awsome with LFS. Really gives you a sense of being in the car when you are close to the lens. I have noticed more eye strain after long sessions though compared to my LCD monitor without the lens. Feels kind of like a CRT with a low refresh rate.

I'll probably have to build a cockpit so I can mount it closer now

Here's some crappy pictures :P

[drgig]

hey everyone, i just found this awesome thread and amazing idea!

i work for a machine vision company, programing digital cameras and pc's to take and inspect images. we worked on a project about 2 years ago where we needed to use a fresnel lens to increase the linearity of the light to get a more accurate measurement. we normally do this by MOVING THE CAMERA FURTHER AWAY, this is exactly what the fresnel lens does and why we used this. this concept and idea is awesome.

i will check at work on monday, i'm pretty sure we have samples of the material we used (it wasn't glass, so i hope it won't distort the image or colours - that system was black and white and backlit). i hope it works.

[bobvanvliet]

Here's some crappy pictures :P
Are those before and after pictures from the same viewpoint? Then they really show this works wonders :thumb:.

[BlueLine]

Are those before and after pictures from the same viewpoint? Then they really show this works wonders :thumb:.

Same viewpoint (as close as I could get anyway :D ). Makes the monitor seem about 4 inches bigger at my normal driving distance.

[MyBoss]

WOW, When I move out from home I am definately going to buy something like that.

[thisnameistaken]

Same viewpoint (as close as I could get anyway :D ). Makes the monitor seem about 4 inches bigger at my normal driving distance.

Looks like it takes a lot of the glare out of the monitor too. How does it look in a bright room though? Can you still use it in daylight?

[SlamDunk]

Somehow I always read the topic as "Anyone used a Lens Flare with LFS?". I know it looks impossible but that's the way my mind is seeing it :p

[TagForce]

Still solving problems with payment here. What is your monitor size in mm? What is the distance between the screen surface and the lens?

I'm going to buy at DIY Projector Company (http://diyprojectorcompany.com/) such a lens : 395x395 f=330. If it will be too tall, I'll make one dimension smaller with scissors or metal scissors.

BTW, if I put 17" monitor beyond a f330 lens, I will have 70" monitor (1 meter deep inside the lens). :D

I'm writing an article on this topic. The first part, theoretical of course, is almost finished, I will publish it tonight.

I have this setup now, and trying to use 2 screens is quickly becoming a nightmare... These lenses distort the image so freakishly much that you won't be able to use the outside 2" of the lens. To counter this you should be as close to the lenses as you possibly can, and doing that will have the effect of having to turn your head to look at the edges, moving your eyes away from the focal point. Right now, I don't have the lenses fixed to the screen, but once I get that done (tonight) I will be able to move the screens a lot closer to me. By the way the image distorts, I think you should not have more than 55cm between the edge of the screen and your eyes, and the lenses fixed at about 20cm from the screen... This is going to be a problem for those of you who like to have a little distance between their wheel and their body, because your wheel will have to be inside your monitor.

[BlueLine]

Looks like it takes a lot of the glare out of the monitor too. How does it look in a bright room though? Can you still use it in daylight?

It seems to kind of tone down the 'crispness' of colors from my LCD (if that makes any sense). I guess it's too bright for my camera on its own.

You will get a lot of glare and reflections in bright light using a fresnel lens though, unfortunately.

[Chaos]

So, it took some time, but here are the promised photos...

[KiDCoDEa]

your last photo, the one thats more important, is very unfocused. can u take a better picture please?

[Shotglass]

mwahahaha i love the lego stand for the lens

[Chaos]

your last photo, the one thats more important, is very unfocused. can u take a better picture please?
well with flash, the photo is focused, but you can't see a thing in the lens because of the reflection, and without flash i can't hold my hand still enough... I'll try, but no promises...
mwahahaha i love the lego stand for the lens
hehe, built in 5 mins and does its job ;) at first I thought of a better stand, but now I think I don't need it ;)

[mrodgers]

Bummer, the last pic, the one I really want to see, I can't load for some reason. Probably my crappy dialup, I'll try it later.

[Chaos]

ok, I shot about 10 more pics and this one is the sharpest...

[NotAnIllusion]

Lol are those legos hold it up?!

Looking good, must say :)

[wheel4hummer]

http://www.lumenlab.com/
http://studentwebs.winona.edu/btoconno8639/index.html

[Jo-Chen]

I'm also interested in this and I think such a setup
http://forum.rscnet.org/showthread.php?t=228229&highlight=fresnel
would be something I would like to have. But what about the distance of the viewer to the lens, how much does it influence the distortion, magnification, etc. of the percieved image? Would a setup like the above be useable to watch a movie on the couch placed several meters away? I can't really imagine how this would affect the image.

[detail]

Finally, I've got my package: F330, 2 200x160mm lens (don't know where to use thoug :)), and 10 visit-card lenses as a presents for friends. In 2005-2006 I had a different debit card, which was not accepted by some payment systems. Now the new one worked well, and I've bough some lenses.

First, I took my own lens depth calculator and reconsidered carefully the focal length and dimensions. Conclusions:

1. The main thing in the lens is large real FOV to involve peripherial vision, and monitor width improves your results a lot. 19" makes real FOV significantly more than 17", 20" is even more advantageous, and so on. Though, according to my tests, even 17" monitor works good.

2. 330 mm is the best length for gaming. 3dlens.com wrote "for gaming" in the description of F330, but not in F280's, and they're absolutely right. F280 is a bit short and makes not enough visible depth.

3. Significantly longer or shorter focal length makes lens very hard to use. Longer = less visible FOV; shorter = less depth, hence tires your eyes.

I'll make a box to attach the lens to the monitor and will post the pictures tonight.

[mikey_G]

I've always wanted to buy a fresnel lens, but always doubted between a 550 or a 330. I think I'll just get the 330 trusting the homework you've done regarding fresnel lenses :smileypul

[detail]

Not that soon as I thought. We had issues with Oracle BPM system in the office, had to have all hands to the pump. :schwitz: Came home at 23:00.

So, here is my temporary fast solution. Look, this is why one should read a lot. :D I usually sit close to the table, with hands on kbd under the desk, and the monitor stands at the other side, in 1 m from the eyes. In this case I had to move it close to me. Driving with mouse won't lead you to many wins, but in this case it is convenient.

In the second picture, this is a medium-size lens, 260*180mm. In the third, a visit-card lens. Makes crooked picture on high magnifying rate (as in the photo), but still does magnify, and can be a nice souvenir, if you can't find this in a store in your area.

Discovery #1: look through the center of the lens.

I supposed something of this kind, but couldn't imagine it would be such a problem. So, I had to rise the center of the lens (and monitor as well) up to the level of eyes. Still, these books in the picture were not enough. I didn't want to risk to raise things higher, and instead took an old small stool.

Not a discovery #2: you can look into the lens as close as you want, if there is enough magnifying and depth.

Discovery #3: the monitor looks very different. Things look like real-life-size! And the screen covers large FOV, which changes perception a lot! You can percept your car shaking with a different sense: if you roll over, it "feels" like you are rolling and hitting the ground. (You need "1g head move" parameters to be >0, about 0.03 m) :thumbsup:

Discovery #4, not good: the picture is a bit blurry. Colours "leak" a bit, and the picture is not as shar as without the lens. Reduce the distance between the lens and monitor to reduce magnifying factor and also draw back from the lens, to reduce the angles of refraction. So, again a trade-off: FOV vs sharpness.

Discovery #5: it is better to use the lens in a dark room. I'll make a box, black lustreless inside, but still the light in the room will make glares.

[GabbO]

And, is it worth it?
What do you think?

[detail]

Yes, it does. I like it, and the small visit-card-lenses are cool thingies.

[Batterypark]

I use a cheapo fresnel lens with my setup and it really is a fantastic way of allowing a higher FOV setting and greater immersion.
after reading some of these links, I'm seriously thinking about getting a couple of those 'high res' F550's and using my old monitor for a dual monitor setup..

Anybody successfully had a radeon 9800pro (or any radeon, I s'pose) running LFS across 2 monitors, or is it only Nvidia cards that can be used this way?

Worked on my X800XT at least, didn't try it for very long as my monitors were of different size etc.