# Thread: Zomm Factor with 47"LCD

1. ## Zomm Factor with 47"LCD

Hello all,

since i havent enough room for a projector, i mount a 47" Full HD LCD in front of my sim. My eye-point is about 1m away from the screen. The question is, what fs-zomm factor is correct for this setup?I played around with man different zomm factors, but i could not get an usable results until now.

It always seem that the outside view isn´t correct, so it is very difficult to make visual landings. Any ideas what i can do to get it work?

Have a nice day

Thomas

2. What do U mean by "non correct"?
Any picture.

3. ## I am not sure zoom is your problem

Thomas

I am not sure zoom is your problem

Try .50

or

Raise the eye point using SHIFT ENTER

or

Raise eyepoint in the Aircraft.cfg
[Views]
eyepoint=

or

Tas

4. It seems to me that the zoom factor is an arbitrary value.

Here is the ideal situation. You are sitting in the cockpit of a real aircraft, and there's a person standing on the apron in front of you. You can see his head and feet. There is an angle through which your eyes have to rotate to go from looking at his feet to looking at his head. Obviously this angle depends on the height of the person and your distance from him.

Now sit in the virtual cockpit and put that man in the same place. Yes, I know, you can't do that, but this is a mind exercise to describe the zoom thing, so bear with me .

So in order to have the view "correct" you need to be able to rotate your eyes through the same angle to scan from feet to head. The complication here is that not only does this depend on the height of the person but it also depends on your distance from the screen AND the zoom factor.

However, I think there's a simple way to set the correct distance from you to your screen, which removes one of the above variables. Take a look at the attached diagram which shows three screens, not one. These screens are all the same size, and are placed at 45 degrees to each other.

If you place the forward left view on the left screen, the forward view on the centre screen and the forward right view on the right screen, you should get a perfect 90 degrees panorama - but ONLY if your head is placed so that each screen is at right angles to your line of view, as shown in the diagram.

Yes, I know, you won't get a perfect panorama because of the screen surrounds, but my analysis regarding your distance from the screen still holds!

Doing a spot of trigonometry on that diagram tells us that the distance from your head to the front screen is the width divided by 0.83. NOT the diagonal distance - you'll need to measure the width of the image, which for your 47" screen will be about 37.5" if it isn't a widescreen, and about 41" if it is. So your distance from the screen should be 45.5", or 49" (for widescreen), or thereabouts. But make the actual measurement and do the calculation.

So you are really too close to the screen at 1M.

And if you set the zoom to 1.0 as a starting point, you'll get the correct view. Even with only one screen.