An aperture membrane is a section of enzine forming the base of an aperture.
"Aperture" means "opening".
"Aperture" is a synonym for a break or a crack. "Aperture" is used in many modern day phrases such as camera aperture and of course, "Aperture Science" from the game Portal.
The aperture of my camera lens will not open!
Aperture Foundation was created in 1952.
Aperture magazine was created in 1952 by a group of photographers and writers.
There is no standard collective noun for 'envelopes', in which case a noun suitable for the situation can function as a collective noun; for example, a box of envelopes, a pack of envelopes, a stack of envelopes, etc.
Maximum aperture is the maximum amount you can get a hole to open.
The aperture ring changes the lens aperture which controls how much light reaches the film or digital sensor. A large aperture f/1.4 to f/2.8 = lots of light, fast shutter speeds, narrow depth of field A small aperture f/9+ = much less light, slower shutter speeds, wide depth of field
Envelopes is correct.
Envelopes come in several shapes and sizes. I assume Hallmark envelopes can be printed in any printer designed and capable of printing envelopes.
The word aperture does not apply to the lens itself. In a camera, the aperture is the diameter of the shutter opening which allows light to reach the lens.