This is from another forum, but I think it's an interesting topic...
Here’s what Otto Carius has to say about buttoning up in “Tigers in the Mud” p. 117-119.
“The most important consideration came after all the material conditions were filled. The personal aggressiveness of the commander while observing was decisive for success against numerically vastly superior enemy formations. The lack of good observation by the Russians often resulted in the defeat of large units. Tank commanders who slam their hatches shut at the beginning of an attack and don’t open them again until the objective has been reached are useless, or at least second rate. There are, of course, six to eight vision blocks mounted in a circle in every cupola that allow observation. But they are only good for a certain sector of the terrain, limited by the size of the individual vision block. If the commander is looking through the left vision block when an anti-tank gun opens fire from the right, then he will need a long time before he identifies it from inside the buttoned up tank.
“Unfortunately, impacting rounds are felt before the sound of the enemy gun’s report, because the speed of the round is greater than the speed of sound. Therefore, a tank commander’s eyes are more important than his ears. As a result of rounds exploding in the vicinity, one doesn’t hear the gun’s report at all in the tank. It is quite different whenever the tank commander raises his head occasionally in an open hatch to survey the terrain. If he happens to look halfway to the left while an enemy antitank gun opens fire halfway to the right, his eye will subconsciously catch the shimmer of the yellow muzzle flash. His attention will immediately be directed toward the new direction and the target will usually be identified in time. Everything depends on the proper identification of a dangerous target. Usually, seconds decide. What I said above also applies to tanks that have been equipped with a periscope.
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“No one can deny that the many casualties among the officers and other tank commanders were due to exposing their heads. But these men didn’t die in vain. If they had moved with closed hatches, then many more men would have found their death or been severely wounded inside the tanks. The large Russian tank losses is proof of the correctness of this assertion. Fortunately for us, they almost always drove cross-country buttoned up. Of course, every tank commander had to be careful while peering out during positional warfare. Especially since the turret hatches of tanks in the front lines were continuously watched by enemy sharpshooters. Even a short exposure could be fatal for the tank commander. I had commanded a folding artillery scope for just such cases. Actually, such a scope shouldn’t be missing in any fighting vehicle.”
Otto Carius, Tiger 1 commander, over 150 tanks destroyed.
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I think Carius’s credentials speak for themselves.
Carius is the first from the left, on the front of his Tiger.
And a little curiosity: Do you know that some guy named Hayao Miyazaki painted a Manga based on Carius' "Tigers In The Mud" book? The Manga is called "
Otto Carius: Doromamire no tora" (Tigers Covered With Mud) If anyone wants to take a peek, go to:
Otto Carius - The Miyazaki Web
Cheers,
Fab