Myeah... Trojca.... that says enough....

I agree that Mr Trojca is inclined to flights of fantasy but he has it right in this case. The FG 1253 drivers’ scope is nothing more than a FG 1250 gunner’s sight that failed testing specifications.
That is to say the quality of the tube after manufacture was insufficient for gun applications (up to 600 meters) but adequate for driving purposes (100 meters) and labelled as FG 1252 – the drivers’ scope on the sdkfz 251 serries.

FG1253 and FG 1254 were vertical and horizontal periscope versions of the drivers’ scope. The unit illustrated in FJC’s post was used in trucks mounted through the roof and braced with a frame.

What made the FG 1250 a gunners’ scope as seen on the Panther was the inclusion of a Panther’s gun sight aiming graticule at the end of the scope – that’s the extra power cable running out to the end. See it’s visible on the MG42 mount but not the drivers’ scope.

The Germans had over 70 pieces of IR equipment (including thermal gear) for the Navy, Army and Luftwaffe not just the few you’ve shown.

Quoted Text

---

I agree that Mr Trojca is inclined to flights of fantasy but he has it right in this case. The FG 1253 drivers’ scope is nothing more than a FG 1250 gunner’s sight that failed testing specifications.
That is to say the quality of the tube after manufacture was insufficient for gun applications (up to 600 meters) but adequate for driving purposes (100 meters) and labelled as FG 1252 – the drivers’ scope on the sdkfz 251 serries.

FG1253 and FG 1254 were vertical and horizontal periscope versions of the drivers’ scope. The unit illustrated in FJC’s post was used in trucks mounted through the roof and braced with a frame.

What made the FG 1250 a gunners’ scope as seen on the Panther was the inclusion of a Panther’s gun sight aiming graticule at the end of the scope – that’s the extra power cable running out to the end. See it’s visible on the MG42 mount but not the drivers’ scope.

The Germans had over 70 pieces of IR equipment (including thermal gear) for the Navy, Army and Luftwaffe not just the few you’ve shown.

---

Any reliable sources for this information?

I've searched for FG 1253 on the net and didn't really find anything on it, apart from one post on Feldgrau.net.

Would I?

The only problem is not being in the UK

Sounds like you’ve got the hang of this. When you say a small sight for the driver yes but it would be under cover so you wouldn’t see it anyway. You could give him IR goggles, I haven’t seen much in the way of German development but the allies had a trunk load full of them, both head and helmet mounted.

You could put a separate exhaust for your auxiliary generator on the rear deck like the old panzer IV turret traverse muffler but that would of course increase your vehicles thermal signature – something both sides were investigating at the time. What about an external socket for IR recharging?

If you can get hold of the 30cm (PaK 40) searchlight that comes with the AFV club UHU set would look good clamped to the mantlet preferably in some armoured box with a shutter. From a purely technical point of view the angle of illumination was best offset - that is to say the greater the angle of the illumination source to the receiver the better as it avoids back scatter. The 251 UHU worked best when it was offset to the Panthers it worked with. However with a fixed assault-gun weapon you are limited and the light and sight must traverse/elevate with the weapon.

When the sights were first shown to Gudarian as mounted on the PaK 40 he at once saw the potential but deemed that was purely defensive. He wanted IR sights for offensive use only so don’t think of your E25 as a defensive ambush weapon. In your world the Germans are back on the offensive pushing into the Urals….

The Germans had developed a special paint for U-Boats that reflected IR – it was a clear suspension emulsion which had reflective particles of a certain wave-length in it. However a glossy AFV would stand out during the day. Play around with your camouflage but remember paint schemes only work when the vehicle is stationary, once it starts moving the paint scheme is void.
Not urban camouflage, remember your out in the open Russian fields again. Natural camouflage (tress, bushes etc.) are great for breaking up the vehicles shape but the trap there is all natural vegetation gives of a unique IR signature which changes as the foliage dies. The Germans used IR photographs to look for changes in foliage during the war. Dr Gaertner was a specialist in IR photography. All markings should be in IR absorbing black which would be acceptable during the day and would stand out better to your friends at night.

While dry-fitting all the mess I realized I wasn´t sure if the main IR searchlight is correctly placed...Taking into account the IR sight for the gunner is on the opposite side of the mantlet! Does IR light cast shadows?

It's not like you could just fit an IR sight and be done with it. Therefore with the Ausf. F of the Panther, the hull and turret were redesigned internally to accomodate the gear, plus be ready instantly to mount it. On the Ausf. G, the gear was stowed externally in a large box at the right rear of the hull rearplate.

If you can swap it to the other side, move it further forward on the mantlet and reduce its size by a third which is not essential but would be more proportional to the subject. If you can lower the drivers periscope as well.
I like the 20/30mm sub-cal arrangement and s/l.
To answer your question yes IR light casts shadows – it behaves in exactly the same way as visible light – shine, reflects and attenuated by smoke and fog.

The UHU would indeed illuminate the battlefield but that was mainly for target identification and acquisition, it would then (using its Fu5 tank radios) talk the IR tanks on to the target. Once they got into ‘their’ zone of around 400 meters would use their own s/l and sight combination to target and destroy the enemy tank.

The removal of rounds from the Panther was not to accommodate the extra battery but for a stand that held the GG400 generator used to charge the extra battery the tank carried – the same as the command versions.

The UHU was not full of batteries but was full of the 8Kv generator set which was the standard gen-set for the 60cm searchlight in Luftwaffe use. The UHU used the standard s/l and gen-set just with an IR filter over it.

The Panther F was in no way IR ready and no provision had been made for the equipment. It would have used the same ‘add-on’ set-up of the Panther G had it ever bee in line to receive the gear. By the time the go ahead had been given to the IR development for tanks the Panther serries was too developed to include such equipment under armour and the lash-up as seen was what was accepted. Nothing in the German inventory existing or planned was designed from inception to carry infrared equipment. It was still very esoteric at that stage of the war.