wrong FOV

[Logan54]

null

[Flappie]

Great comparison shots. Where do they come from?

[Logan54]

50 минут назад, Flappie сказал:

Great comparison shots. Where do they come from?

I think they are from Czech aviation museum. I asked @SVKSniper for doing them long time ago. I also shared them before in russian Hind thread to ask more contrast and realistic filters, but no result. Narrow one is "no filter", wide is "orange+blue" I think. If you need high res, I can share.

[Weta43]

& how far away were the 2 sets taken from (if not the same, it's no comparison)

[Logan54]

1 час назад, Weta43 сказал:

& how far away were the 2 sets taken from (if not the same, it's no comparison)

Much far away then I located in DCS

Edited April 14 by Logan54

[AeriaGloria]

I mean we know for a fact the narrow FOV is 7.33 degrees and the wide 22. Shouldn’t be hard to verify those. 

[Flappie]

14 hours ago, AeriaGloria said:

I mean we know for a fact the narrow FOV is 7.33 degrees and the wide 22. Shouldn’t be hard to verify those. 

What we have in DCS seems pretty close to these values.

FOV_Hind.trk

[AeriaGloria]

4 hours ago, Flappie said:

What we have in DCS seems pretty close to these values.

FOV_Hind.trk 356.92 kB · 0 downloads

Interesting! That does explain why Petro can acquire so much despite using narrow, I had no idea it was using 7.33/22 degrees as a radius and not diameter. 
 

The manual does warn of the sight being blocked in a left hand turn while looking left, so if it was half that I guess it wouldn’t be so true. 
 

The sources we have don’t indicate if this number is radius or diameter at all 

[Flappie]

3 minutes ago, AeriaGloria said:

Interesting! That does explain why Petro can acquire so much despite using narrow, I had no idea it was using 7.33/22 degrees as a radius and not diameter.

I only measured the left half of the optics (space between two soldiers = 1°):

• ~ 3.5 for Narrow x 2 -> 7°
• ~10.5 for Wide x 2 -> 21°

[Czar66]

4 hours ago, Flappie said:

What we have in DCS seems pretty close to these values.

FOV_Hind.trk 356.92 kB · 0 downloads

Isn't  FOV (field of view) calculated for the whole view instead of half, hence the name?

Edited April 15 by Czar66

[AeriaGloria]

15 minutes ago, Flappie said:

I only measured the left half of the optics (space between two soldiers = 1°):

• ~ 3.5 for Narrow x 2 -> 7°
• ~10.5 for Wide x 2 -> 21°

Ah, makes sense! So it is diameter! 

[Weta43]

It should be, which implies the DCS FOV is 2x what it should be...

Angle of view (photography) - Wikipedia

Edited April 15 by Weta43

[Logan54]

Just a bit easy math. We know, that FOV depends on screen and for 21/9 screen (that I have) it will be 78° horizontal and 39° vertical. Hind sight is circle that have 1395 pixels diameter for any FOV.

I will use analog of mil, that using in russian artillery math. T= 1 m target at 1000m distance. It also equal 0.06 degree. So, in 39° we have 39/0.06=650T (FOV 1x sight in T equal)

I locate containers at distance 1000m that have 50T (50m length) and 65T (65m length) length indication.

We have "normal ingame FOV" (for 21/9) =650T, so for 50T target it will be FOV(1x)=50T*13  (650T/50T=13) That means 50T target 13 times smaller then 1395p for 1x FOV

Now we can find equal FOV settings for 3.3x and 10x (This is ultiplicity of the Hind` sight, that I found in wiki)

Lets start with 3.3x wide FOV: FOV(3.3x)=650T/3.3=197T.  (When you using wide FOV you will see 197T max diameter, that equal 650T/197T=39°/x, where x=197*39/650=11.82° screen equal for 21/9 in 3.3x FOV).

Check: 39°/ 3.3=11.81°, correct.

Now time for 10x FOV. FOV(10x)=650T/10=65T. (This means in 10x FOV you will see 65T target at 1000m at full sight. 650T/65T=39°/x, x=65*39/650=3.9° screen equal for 21/9 in 10x FOV.)

Check: 39°/ 10=3.9°, correct.

What this math for? Max. sight diameter with 3.3x FOV=197T, and 10x FOV=65T.

Lets check current ingame FOV:

I have 50T and 65T marked target (length=50m and 65m at 1000m distance from Hind).

For wide ingame FOV I have 50T target=188 pixels. But full sight at 3.3x=197T, so its about 4 times more then 50T.

188p*4=752p. But I have 1395p sight diameter. It means that current ingame FOV not correct and should be zoomed in 1395/752=1.855 times.

For narrow ingame FOV I have 65T target=730pixels, but my screen 1395p still. So for realistic narrow ingame zoom should be 1395/730=1.91 times bigger then now. 

PS: I can be wrong in this calculations on the knee, so you able to check it. Hope not too much words. Very much math depends on game "standard FOV" and screen dimentions. I did math for 21/9 (3440p/1440p) screen. Also used microsoft Powertoys ruler for searching pixels. Hope this will help.

Edited April 16 by Logan54

[AeriaGloria]

On 4/15/2025 at 3:42 PM, Weta43 said:

It should be, which implies the DCS FOV is 2x what it should be...

Angle of view (photography) - Wikipedia

It seemed to me that Flappie just labeled in an easy to misunderstand way, and really meant diameter even though the mark is only for radius on the picture. Likely because they measured radius then doubled it to get the correct measurement. 

[Flappie]

Yes. And my JPEG picture does not help (my 3.5 segments look like 7 segments in the first pic). Sorry for the confusion.

If you want to make sure, run the track: there is one degree between each infantry soldier.

[Logan54]

Good example of how FOV depends on multiplicity.