Calibrated Sight Magnifications For All Playable Tanks

[MajorMagee]

 

Here's a comparison table of the base game Field of View (FOV) min/max values versus the calibrated (extra max) values. Since higher FOV values imply less magnification, you can see that for most sights the base game provided more zoom than it was historically accurate to have. To lessen the impact of this, you can still use the extra zoom available through the mouse scroll wheel in these two versions of the mod to reach the extra min FOV values.

 

The first version lets you zoom in to the equivalent of adding a doubler eyepiece (2x) to the calibrated sight's actual magnification. This still leaves the M4A2 wanting for more as the base game's lowest magnification (40 degree FOV = 2.6x) is still better than the calibrated value +2x (42.1 degree FOV = 2.5x). The reality is that the 1.25x historic sights in the Sherman were essentially useless beyond 500m.

 

The second version simply lets every tank zoom in as far as a 10x sight equivalent (12.8 degree FOV = 10x) so you can sharpshoot to your heart's content.

 

 

I built the calibration curve by methodically taking images at a 90 degree FOV from a fixed location and measuring the distance between two easily identifiable widely separated sharp edges, and then taking the same images again at a variety of FOV values. The ratio of the increase in measured distance as the FOV went down let me build the calibration curve to an accuracy of 99.66%. If you determined that some other FOV than 90 degrees was the equivalent to 1x then the process would have to be repeated to create a different calibration curve. 

[moustache]

well said, nice work... thank you for the mod, it will bring a little realism...

[MajorMagee]

I've added two more versions calibrated for the 75 degree FOV being 1x magnification. Some may find this matches their monitor set-up better.

 

 

[MajorMagee]

If you want to check your monitor set up to see which FOV is equivalent to a 1x magnification the process is pretty straightforward.

 

1. In the mission editor create a situation where two vehicles/objects are positioned exactly 100m center to center (View Size), exactly 500 m (View Distance) from the player vehicle. The mission editor has grids and a ruler that can help with the positioning, and the arrow keys can nudge items around in 1 m increments for fine tuning.

 

2. Use this mission in the game and, center the target objects in your view so they are centered on your screen to avoid edge distortion.

 

3. Measure the distance between the two vehicle/objects center to center. (Screen Size)

 

4. Measure the distance from your eye to the center of the screen. (Screen Distance)

 

5. For a 1x Magnification Screen Size / Screen Distance = View Size / View Distance

 

6. Try different FOV settings (+/- key, or mouse scroll wheel) until the Screen Size is correct for your Screen Distance.

 

For example if your Screen Distance is 0.5 m then 0.5 m x 100m / 500 m = 0.1 m would be the correct Screen Size to measure for a 1x magnification. 0.2 m would be 2x magnification. etc.

 

p.s. Your Screen Distance and Screen Size don't have to be in meters, inches will work just the same. 20 in Screen Distance x 100 m / 500 m = 4 inches Screen Size @ 1x magnification.

[MajorMagee]

If someone needs a calibration other than the ones based on 90, or 75 degree FOV just let me know.

[MajorMagee]

In taking a look on my calibrated range at the German Binoculars 10 mil Gradient versus the Panther Sight 4 mil Reticle I found that they're both slightly off.

 

The Binocular markings are too widely spaced, and the Panther Sight triangle spacing is too small.

 

At 500m the binoculars estimate it at 521 m (104.2% of actual range), and the sight comes in at 487 m (97.4% of actual range).

 

Probably not enough to cause you to miss the shot, but interesting to note the difference.

 

It would be nice if there was some way to calibrate these by rescaling the reticles.

 

Edited August 30, 2023 by MajorMagee

[MajorMagee]

Ran the numbers on the other reticles today.

 

The Soviet Binoculars vertical tics are 5 mils, and are too far apart, so overestimate 500 m as 519 m (103.8% of actual range)

 

The M4A2 Circle Diam., Horizontal Bar Lengths, and the Distance from the Dot to the Inside Edge of the Bars are all 10 mils. They are all too small, so underestimate 500 m as 488 m (97.5% of actual range).

 

The Churchill MG vertical tics are 8 mil and are too close together, so underestimates 500 m as 485 m (97.1% of actual range). The main gun underestimates it as 485 m (96.9% of actual range).

 

The Su 152 vertical tics are 4 mil and are too far apart, so overestimates 500 m as 518 m (103.5% of actual range).

 

The T-34 and KV-1 vertical tics are 4 mil and are too far apart, so overestimate 500 m as 519 m (103.8% of actual range).

 

The Su 122 main gun vertical tics are 4 mil and are too far apart, so overestimate 500 m as 521  m (104.2% of actual range). The commanders view vertical tics are 5 mils and are too far apart, so overestimate 500 m as 521 m (104.3% of actual range).

 

The Stug III, Elephant, Tiger, Pz III, and Pz IV all scale out the same as the Panther (see previous post).

[MajorMagee]

The vehicle spacing is 10m and 15m center-to-center at 500m distance. 10m is 20 mils at 500m. (15m is 30 mils, and 25m is 50 mils) The Sherman was at the center of the field of view before cropping.

 

German Bino 5-10 mils

 

Panther 4-8 mils

PzGr.39/42 scale is AP, Pak Gesh 40/42 scale is APCR, Sprgr.42 scale is HE (and MG)

 

M4A2 10 mils (Circle Diam., Horizontal Bar Lengths, and the Distance from the Dot to the Inside Edge of the Bars)

 

 

Tiger MG 4-8 mils

 

Tiger 4-8 mils

 

Churchill MG 8 mils

 

Churchill 8 mils

 

Su152 4-8 mils

From the station notes:

The range scale on the left works for the HE only. None of the scales are correct for APHE, you have to watch the text on the right as you make adjustments to know what you have the distance set for.

 

Pz IV and Pz III 4-8 mils

Pz IV Pzgr 39 scale is AP, Pzgr 40 scale is APCR, Gr 34 u MG scale is HE and MG, Gr 38HL/C is HEAT

Pz III Pzgr scale is AP, Sprgr scale is HE (and MG)

 

KV-1 and T-34 4-8 mils

СГ - "Старая Граната" (Staraya Granata/Old Grenade) it is for Ф-354(F-354) HE round with 640 m/s muzzle velocity

ДГ - Дальнобойная Граната(Dalnoboynaya Granata/High range grenade) - for ОФ-350/350А (OF-350) HE round with 680 m/s

ДТ - machine gun Дегтярева Танковый(Degtyareva Tankovy/Degtyarev's for tanks) with 840m/s muzzle velocity.

 

KV-1 and T-34 Second Sight

APHE БР-350Б (BR-350B) have 655 m/s velocity.

 

Su122 4-8 mils

 

Su122 Commander 4-8 mils

 

Stug III and Elephant 4-8 mils

 

Soviet Bino 5-10 mils

 

 

Edited September 2, 2023 by MajorMagee

[MajorMagee]

I was trying to figure out a way to have these images show up inside the crew compartment. I found an effective way to overlay these on the interior so they would show up as black lines on the interior paint near the gunner's station. Unfortunately even at their maximum size (4096) the interior texture resolution is not high enough for a reasonable level of detail to survive the downsizing of the line art with any sort of reasonable fidelity. Rather that letting them go to waste here they are for reference.