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Jake 747 400
02-23-2009, 06:22 PM
Hi everyone.
Does anyone know the minimum distance the the surface projected on can be to the projector or front of the sim.
If it different for specific aircraft, its B744 im building.
Thanks.
Jake

fordgt40
02-23-2009, 06:44 PM
Jake

The minimum distance from the projector to the screen depends on the make and model of projector and this can vary considerably between ultra wide and wide angle/short throw projectors. The link below is one of many available on the web which will give you an idea.

I think that you should work back from what size screen you want and then establish whether you can get a projector that will both fit within your physical constraints on both distance and angle from the projector mounting to the bottom of the screen.

http://www.dalite.com/products/projection_calculator.php

Regards

David

Jake 747 400
02-23-2009, 06:48 PM
Hi David.
Thanks for the reply and advice.
I will check the link out thanks.
It was just so I know how much longer than the sim I have to build the shed.
Thanks
Jake

MartinK
02-24-2009, 06:22 AM
Hi Jake,

Before you start drilling some poles into the ground and poor some concrete for the fundament of your shed there are a few more questions you might want to ask yourself, like e.g.:
- what pricerange projector can I afford? Short throw projectors come far
more expensive then projectors with regular lenses.
With regular projectors (say around 500 Euros) you will need approx 3 mtr
of throw range.
- do you want front or back projection. With front projection you need to
have the proper height in the shed otherwise your own pit (or at least your
overhead will get in the way.
If you decide for backprojection using a 'non' short throw projector you will
need the throw length in addition to the lenght of your pit.
- What screen material can you afford. Crytal clear type of projection screens
will help to make the outside world look better but will cost more.

If I might suggest, start experimenting if possible somewhere else in the house with preferably 1 projector and some pieces of wood you might have laying around to represent the shape of the pit.
I can tell you from experience: I did the same thing on my loft and it totally changed the originals plans I had.

Hope this helps.

Cheers,

Martin

767300
02-27-2009, 05:16 PM
Hi guys,

That projection calculator is brillant!! Should be a sticky!! Any advice on Screen materials, for both front and rear projection.

Thanks again for the advice.

James

warvet
02-27-2009, 07:28 PM
James,
Best advice I can give is no matter what type of material you use make sure its a Dark greythis will cut glare and ensure true blacks and high quality clear color. MDF makes a good material for screens and is very easily formed to curves also PVC sheet or Cintra. You can use Cloth Sheets with High thread count that have been dyed, just some suggestions.You can also loo at this as well http://www.paintonscreen.com/
Hope this helps.
Tim

fordgt40
02-27-2009, 07:30 PM
James

In addition to Tims good advice do a forum search on Black Widow paint

Regards

David

Goldmember
03-07-2009, 09:47 AM
The calculator is brilliant but what I miss is how close to the screen you can put your cockpit before you create a shadow. Obviously everybody wants their screens as short as possible to the cockpit to save room. Therefor the projectors have to be behind/beside the cockpit but the question is, what is the limit? Also, how high must the screens be?

Any experience?

mpl330
03-07-2009, 10:38 AM
The calculator is brilliant but what I miss is how close to the screen you can put your cockpit before you create a shadow. Obviously everybody wants their screens as short as possible to the cockpit to save room. Therefor the projectors have to be behind/beside the cockpit but the question is, what is the limit? Also, how high must the screens be?

Any experience?

Hi,

Currently testing my setup and at the moment I have an Optoma EX525ST short throw projector. At the moment it is 1.95m off the ground and about 1.9m from my 'screen' i.e. the wall. The wall is currently 1m from the face of my MCP. Havent measured the image produced but it is approximately 1.8m wide and at least 1.5m tall.
Still playing with it but I don't think there will be much change...

Cheers
Mike

Redbirdman
03-21-2009, 05:45 PM
Also, how high must the screens be?

Any experience?


I am using an older (almost free) Toshiba S30 projector that really changed my whole concept of flight sim. First let me say it has a bulb life supposed to be about 2000 hours and I got it high time! How real is that compared to real world aviation? I actually use a log book to keep track of my bulb hours and if it had a dipstick I would test the oil for metal chips!
I am still experimenting and changing things but here are a few things I found you may want to consider.

My Toshiba (at least, I dunno about other makes) has a fantastic 'convergence' feature that allows the projector to sit on different heights than the 'screen'. Then the 'convergence' adjusts the picture so it is not all warped out of shape by the angle. But AFA the height of the screen; I found it is best for me to have a height equal to the position of my eyeglass 'distance' for infinity, rather than the mid range I would use with a regular set of monitors. Of course, age has a lot to do with these ol'man factors but they should be considered.

The placement of the projector can dump considerable heat on you as well as noise. I actually find both kind of comparable to RW aircraft but here in Arizona where it can reach 122 degrees in the spring a hot projector blowing on a bald head is not fun.
But the biggest problem is the glare from the bulb either lighting up dust particles in the air or reflecting off items in the cockpit or even off the frame of your eyeglasses. You gotta try all these things out and find the best solution.
I project (over my head) onto a white wall about 10 feet from the projector and get an 8 foot by 12 foot wide visual that seems to be the most realistic feel. I also aim the projector up just slightly and have my sim pit angled up slightly as well to trick the mind into not feeling so 'glued to the floor'. My monitor (instrument panel) is also set at a distance for my eyeglass mid-focal distance. The older I get the further away that dimension gets. So while my simpit is not exactly to 'scale' the 'immersion' is the best for me.
Also, while I never tried it, I am told 'spandex' fabric sold in fabric stores works great as a screen. I don't know how you can explain why you will need such a 'wide' piece though and I suggest you don't bring the missus with you when you go to buy it. ( ( )
Hope I shed a little light...
Redbird

SimDeck
03-25-2009, 08:05 AM
Hi Folks
Just some comments on projection screens and the like for your sims. I am a specialist projection screen manufacturere and distributor, sim builder and have spent many years in the large screen biz and in recent years building our own simulation systems with the theme of "We put the reality into virtual reality".

I want to open your eyes up to some new possibilities and for many folk challenge their basic understanding of projection screens. Most of you will be using white surfaces, or a grey paint etc and 2000 - 3000ansi and dark room. It is what many av companies will tell you to do and your own epxerience will tell you similar. However this is the completely wrong approach to projection and especially for simulation. The most crucial first aspect to any projection system is NOT the projector but the screen....absolutely and without question.

Here I am not talking about whether a da-lite, draper etc is better than the other but rather a completely different approach using lens technology and principals. With this patented technology (250 world wide) you can use a 3000 ansi lumen projector in a vast range of well lit areas and still achieve PERFECT images without turning the lights off, or use a far lower light projector and still can far brighter, higher res images than using a projector 3x the cost. Most people do not realise that a white screen in a well lit room (say take your lounge tonite with all lights on that this screen) will discard up to 95% of the projector ansi lumen. A typical grey/white screen can only deliver a perfect image in the absence of environmental light, hence why you always need to turn the lights off. Our ICE screens do the opposite in many situations, lights on or off absolutely do not make any difference.

Our motto is "The Magic is in the Screen" reinforces that your screen is the critical aspect of your display. I see some one asked about HDMI, resolution etc etc.... hear me out on this thought....
Everyone is after the perfect largest image at the lowest cost in any application in the widest possible venues etc....
so what do most do (maybe yourself included) ... look for the highest quality graphics card, then DVI, RGB or HDMI queries, then projector resolution, best projector, 1080P etc, best software for sim etc, which are all valid aspects to consider but in many ways they are secondary....because what happens after you've discussed and disected all these aspect and made your decisions... so as the light carrying your sim images leaves the last lens element of the projector you throw all that quality out the cockpit window and hope for the best by using a typical matt white screen, close weaved bed sheet etc....this is the error most make and very few understand how to resolve this...aprt from flicking the light switch believing this is the best way.

The solution to all these issues is a range of very unique ICE brand screens, that we use exclusively with our simulators...currently we build Formula One cars (actual race cars that are also simulators). Our Lens Screen for example
will increase any projector by a factor of 2000% in brightness, resolving ability of 2 million 2000:1 contrast, ambient light rejection, hues of 3D, suited for all 3D technologies. We have just launched our 2 Gain and 10 Gain Cylindrical Screens for the aviation and other simulation markets.

I have attached some App Notes - please not the photos are all for real as I know the quality will challenge you "is this possible". Please feel free to go to www.digitaldaytime.com and you will discover alot of what we do in this area ...especially the download section and news. You can read about our Sim sde of the business here - www.simdeck.com and check out a pile of videos where we demo, talk about our screens and sim experiences etc.
On our simdeck site there is a category where you can read what others say about our screens and sim experiences.

If you go to www.slideshare.net/simdeck we have a informative slide show where you can see alot more info.

As a small bonus for reading all the way to the end of this post here, I have included a bonus photo of an amazing World War 1 Aviation museum established by Peter Jackson and Richard Taylor. This scene is amazing in reality that recreates a British plane crashed into a tree and the German troops watch over the German pilot and his British counterpart have a gentlemanly conversation. The World Class Museum is in a small airstrip called Omaka just outside of Blenheim in New Zealand. Anyone interested in aviation, simulation will easily spend 4 hours here absorbing an incredible exhibition.

If you would like to discuss on/off line over the phone please do not hesitate to touch base.
Regards
Kevin
ICE AV Technology Ltd
0064-9-414234

PS Here is a link to our latest simulation display solution and have posted some pics in the vendor product section. http://www.box.net/shared/08e9ob86db