Is this an Aviar?

[Simon Benton]

I received a Cooke lens with a bunch of other old camera gear and am wondering if it is an Aviar. On the front it has engraved COOKE ANASTIGMAT 5X7 INCHES No, 55944 f4.5 7 INCH Series II.

I have done some googling on this lens and there are some references that this Cooke anastigmat was an early Aviar. It came in a Number 3 Optimo shutter. Can any of the experts on the Forum enlighten me?

[Dan Fromm]

Why do you ask us when you have the lens?

Ask it directly. If it is a triplet, it will have 4 strong reflections on one side of the diaphragm and two on the other. If a dialyte -- that's what the Aviar is -- 4 strong on each side.

The s/n says it is early to be an Aviar.

[Simon Benton]

It is a triplet. Thank you Dan for the enlightenment.