Has anyone reported the incorrect engine sound for both AMX-32s?
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My report about the AMX-40’s missing composite armor in the turret has been accepted.
https://community.gaijin.net/issues/p/warthunder/i/HZKQSOhBDQwt
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See you in 4 years !
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So there is no way to buff the optic magnification?10x immutable gunner sight is hard to use…
Gunner sights on these vehicles are terrible, surely they aren’t accurate.
@Mulatu_Astatke @LeGrandSarrazin @vizender
The fixed 10x optics is really awful.
We needs a low magnification for wide FoV detection such as 4x-10x or 3x-10x.
I doubt the thermal channels on AMX32120 and AMX 40 may have that low magnification.
I believe that even if they were able to find sourcing that directly states the optics aren’t fixed at 10X, I doubt Gaijin would act to implement it.
There’s many glaring innacuries that have been pointed out by this thread like AMX-32 (105) not having thermals or AMX-40 missing turret composite that have been “accepted” yet have 100% never crossed the eyesight of any dev.
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I don’t remember what magnification the 10x is based on, but I remember looking at all the different magnification, Optical and thermal, but only 10x was mentioned. Until someone finds a source mentioning different magnification, thermal or optical, we are stuck with this sadly
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The x10 is the daylight magnification of the M581 gunner’s telescopic primary sight, not the magnifications of its Castor thermal camera.
The optical characteristics of tank sights are actually like binoculars, and its magnification can be defined by the ratio of the focal length of objective lens to the focal length of eyepiece lens, or the ratio of the effective objective lens diameter to the exit pupil diameter.
M=f_objective/f_eyepiece =D/d
But most parameters such as the focal length or lens diameter of military AFV sights are confidential. Therefore, we can use the original definition of magnification, that is, how large or small a object can be reproduced on the image plane (the degree to which the object being viewed is enlarged) to calculate an approximate value.
The dimension of the object that a sight can observe generally depends on how wide the field of view is. The field of view is inversely proportional to magnification, that is, lower magnification expands it and higher magnification narrows it.
For example, at a specific observation distance, the image dimension observed at a high magnification M_h is M_l/M_h times the image size at a low magnification M_l.
In order to calculate a specific magnification, it can be simplified to the following formula
M_(low for WFoV)=D_(image dimension for NFoV)/D_(image dimension for WFoV) ×M_(high for NFoV)
The Castor thermal camera used by the AMX-40 is a dual field-of-view thermal imager. The following diagram is a typical step-zoom dual-field optical system, which uses different lens arrangements to change the focal length to provide different magnifications (rather than continuous zoom).
Thomson-TRT has designed three lens configurations for Castor for different applications, and the Castor/DIVT-16 system used by AMX-40/AMX-30B2 Brenus is variant 1.
Spoiler
The Castor thermal camera provides x2 electronic zoom. Other sources indicate that the DIVT-16 has a maximum magnification of x20, so the optical high magnification of the Castor is x10.
Spoiler
The approximate value of low magnification can be solved as follows:
Now if assume the object distance = 100 meters, then the given horizontal field in narrow FoV is 71 mils (NATO) and the given horizontal field in wide FoV is 160 mils (NATO).
We may choose base of isosceles triangle formula
(2∙h)/tan((180-β)∙0.5∙π/180)
Thus the horizontal image dimension in NFoV and in WFoV, respectively, which are
D_(horizontal for NFoV)=(2∙100)/tan((180-(71∙360/6400))∙0.5∙π/180)
and
D_(horizontal for WFoV)=(2∙100)/tan((180-(160∙360/6400))∙0.5∙π/180)
Then we use the given NFoV magnification x10 and the magnification rate formula derived above to get
M_(horizontal for WFoV)=10∙D_(horizontal for NFoV)/D_(horizontal for WFoV) =4.4301658696
So here we solve the magnification rate in WFoV, obtaining
M_(low for WFoV)=4.4
Note that this magnification value is an approximation. To verify the accuracy of this formula, we substitute the parameters of other sights to check the error.
AN/VSG-2 TTS, given x8 magnification and NFOV, solve for the lower magnification under WFOV
AN/VSG-X TIS, given x9.8 magnification and NFOV, solve for the lower magnification under WFOV
PERI-ZL, given x10 magnification and NFOV, solve for the lower magnification under WFOV
OIP Mk-2 FCS, given x12 magnification and NFOV, solve for the lower magnification under WFOV
The error is between ±0.5, and the error will increase if the given magnification or field of view is approximate. If one magnification is known, the formula can still calculate the approximate value of the other magnification.
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Wow that’s very interesting. I knew some very basics about optics but you reached me quite a lot of things. Sadly since this is only approximation I am not sure we could make a report on that. Thoughts @WaretaGarasu ?
Do we have any info about Castor thermal camera‘s FoV data？I remember Gaijin accept magnification approximate value by calculating the formula with FoV
I wish these got their psuedo-stabilizers
You mean the FCS that can decide to shoot when the gun is aligned with the firing position even when moving ?
Yeah, that’d need FCS to be implemented sadly
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With every accepted bug report they take forever. This is how it would be though with composites. Taken from the first dev server the AMX-40 appeared in. AMX 40 Dev Server Composite - Album on Imgur
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I think its a bit shameful we have 1 AMX-40 despite them having quite some decent differences (Nothing really extreme, but differences in gameplay nonetheless) while other nations can get dumped with variants
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I feel you forgot about the 20mm autocannon ammunition. Community Bug Reporting System
Independent use of the 20mm. Community Bug Reporting System
Also, is there a reason why amx-30/32 transmissions have slow reverse shifting speed when going downhill? Community Bug Reporting System
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Magach moment.
That “magnification ≈ NFOV_FOV / WFOV_FOV × (high-mag)” shortcut only works if a bunch of things are true at the same time:
- the same detector size is used in both fields,
- the scan/amplitude on the detector is the same in both fields,
- the same eyepiece/display geometry is used, and
- the change from WFOV→NFOV is purely a change of effective focal length.
Thermal sights usually fail one or more of those. In practice:
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- Detector/scan window often changes. Dual-FOV TI systems sometimes crop the detector or use a smaller scan amplitude in NFOV to keep resolution/MTF acceptable. If the scanned width changes, FOV no longer scales exactly as 1/f.
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- Different scan amplitudes. With rotating/oscillating scanners, NFOV may use a smaller mirror sweep than WFOV (or vice-versa). Again, FOV ≠ constant×1/f.
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- Different relay/eyepiece trains. Many vehicle TIs are not “binoculars.” The eye views a CRT/TV or micro-display through an eyepiece, or an optical periscope re-images that display. The quoted “×” is a system (apparent) magnification that depends on the display size and eyepiece, not just the objective focal length. It can differ between WFOV and NFOV.
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- Afocal converters. Two-field optics often add/remove a Galilean afocal in front of the objective for NFOV. Designers may also change field stops to control vignetting and resolution. The net effect is that FOV reduction and apparent magnification increase are not locked to the same ratio.
The method of deriving the low-mag from the two FOV angles isn’t generally valid for thermal imagers, although it gives easy, often correct, estimates. For step-zoom thermal sights, you need the actual optical prescription (focal lengths + afocal factors), the scanned detector width in each mode, and the display/eyepiece geometry. Without those, any “× from FOV” is at best an approximation and can easily be off by 10–30%.
TL;DR:
The formula only works for simple telescopes. Thermal sights don’t behave that way because their scan size, detector use, field stops, and display optics change between WFOV and NFOV. That’s why you can see things like 8× (10°) WFOV and 16× (6°) NFOV instead of the predicted 5°. Real systems break the scaling, so the formula gives only a rough guess.
However, for warthunder, “magnification ≈ NFOV_FOV / WFOV_FOV × (high-mag)” is good enough.
Also, where did you get AN/VSG-X from? Some references list it alongside the TIS in broader manufacturing or Common Module contexts, but it isn’t described as the TIS, and I have yet to see its specifications.
Amx-30’s and others should get their 20mm apfsds belts.
Also, fix the ERA on brebus, please.
Ah yes, the famous cold war era 20mm APFSDS used on the 20mm coaxial of the AMX30