Spitfire Mk V gunsight

[R33GZ]

Hi all, I'm after some info on the Spitfire Mk V gunsight and the ability to adjust its range and base(?) 

 

What does the in cockpit range adjustment do? I thought the convergence setting pre flight is what efeectivley adjusts the firing range....  Am I supposed to match these 2 settings up? I'm not in front of my computer right now, but I think the other adjustment was firing base?  I've no idea what that is for... Vertical convergence? 

 

Any help much appreciated

[Hook_Echo]

There are two adjustments. Wingspan in feet and distance in yards. You need to dial in the wingspan of the enemy plane (33-34 feet for 109-190s). Then you set the distance to your convergence, remember convergence is set in meters but the sight is in yards, so you have to convert. After you are dialed in, the horizontal bars in the reticle will match the setting. When the enemy plane is the same width as the bars you are at convergence distance.

[R33GZ]

Brilliant, just what I was after, cheers ?