BF109 - Can't we just have the gunsight in the middle?

Actually thinking about it I don't think that Lixma's picture is realistic.

BUT:
It might be possible that in fact one did not have to lean right for aim. It depends on how the reflector glas actually worked.

As far as I understood reflector sights the trick is to project light on a surface that is reflected so that the pilot can see it. Now from school we know that inbound angle = outbound angle. That is the benefit of the reflector sight with respect to iron sights because this makes the aiming point almost independent of small head movements. The image will slightly move but it won't impact the aiming as much.

A little picture about the basic principle after which to my understanding a reflector sight works. For simplicity I moved the light source into the same horizontal plane as the eye but the principle won't change at all with a 90° moved light source:



The angle between the reflector glas and the light beam emanating from the light source is equal to the line of sight when the eye is on the image. That's the basical law of optical physics.

Now what happens if the reflector glas is slightly inclined sideways? Yes, the angle between the light beam and the reflector glas decreases and so the angle between reflector sight and the eye line of view. This itself increases the angle between the light beam and the eye line of view so that the image can be seen from further aside. But it will be on the reflector glas and not on the window.

Here a drawing with the setup as described. I exagerated on purpose the inclination of the reflector side to better make the effect visible. Please also keep in mind that with appropriate glas cristal design it should be possible to obtain the same optical result without really inclining the reflector glas.



My strong feeling is that taking into account the tight cockpit dimensions of the 109 and the not so far off-centre position of the reflector sight a very very very tiny inclination would have been enough to allow seeing the image without leaning sideways.

Anyhow I agree with drewpee. I mean we're not talking about making the 109 turn better than the spit. We talk about computer hardware limitations in simulations and as far as I see it there's absolutely no loss in realism if the sights can be recentred on a button push (I even suggested something that is inbetween the current status and old IL2 days).

[Lixma]

Originally Posted by 41Sqn_Stormcrow

Actually thinking about it I don't think that Lixma's picture is realistic.

Why not?

1: You're sat in a 109.

2: Looking straight ahead.

3: Both eyes open.

4: Revi offset to project the reticle image directly into your right eye only.

I submit your view would be more or less like this..... (paintshop skills notwithstanding)



What would you see?

try it yourself, Lixma.

Go to a mirror (the reflector glas is nothing different that a transparent mirror) and see if you can see anything from behind you at the side of the mirror. I guess you won't see anything exept the wall to which the mirror is attached.

[Wolf_Rider]

we understand what you're trying to say Stormcrow, but the old "arcade machine" type reflection system has the source a lot closer than the bathroom wall.

That still cannot defy physical laws. The distance between the light source and the reflecting surface is irrelevant to optical law. Only the angles count. See my previous post one page before.

[Wolf_Rider]

source distance to reflector makes a big difference, Stormcrow. You only get the big shift when the source is a big distance away


http://www.spitfirespares.com/spitfi.../gunsites.html

Gun Cam Harmoniser (Pg 1 Gun)... illustrates my point

its about 1/5 the way down the page

First you won't need a big shift in the 109. And I would also say that the required shift is by far less than in the image you're pointing me to. IF distance of the light source is significant at all which I still doubt. The limiting factor is the size of the reflector glas, not the distance. The distance only plays a role because of optical size reduction with increased distance. But this factor is irrelevant for a particularly designed light image projected actively at a certain angle on the reflector surface.

EDIT: Also reflector surface sideway inclination plays a role (see last picture in my post)

[b101uk]

Originally Posted by 41Sqn_Stormcrow

That still cannot defy physical laws. The distance between the light source and the reflecting surface is irrelevant to optical law. Only the angles count. See my previous post one page before.

the critical distance is if the left edge of the reflector glass is central to the position of the human nose & the nose of the aircraft, if it is then is the distance from the left edge of the reflector glass to the centre of the reflector glass the same distance as the human anatomy from the centre of the human nose to the centre of the right eye.

if yes to all the above then the right eye is in perfect line with the centre of the reflector glass thus reflector light and the brain will naturally merge the left/right eye image in the same manner to if you were to use a marker pen on a bit of clear glass to mark a X and with both eyes open were to position it in line close the right eye, however with respect to the gun sight and the above there needs to be a narrow angle of view for the “reflective recticel” so it cannot be seen at all by the left eye when the right eye is positioned correctly.

Can you make a drawing? I really don't get what you try to explain, b101.

[Lixma]

Originally Posted by b101uk

if yes to all the above then the right eye is in perfect line with the centre of the reflector glass thus reflector light and the brain will naturally merge the left/right eye image in the same manner to if you were to use a marker pen on a bit of clear glass to mark a X and with both eyes open were to position it in line close the right eye

Thankyou!

My reply to you earlier confirmed the positions and measurements regarding the reflector glass and gave some (rough) numbers.

http://forum.1cpublishing.eu/showpos...6&postcount=97