Corrective Lenses Question?

[Belmont]

I bought daily contact lenses, no big expense if I loose one while diving.
Also, in a bind, you can try making with your thumb and index the divers OK sign, but very tightly, thus leaving a very small hole (the size of a pencil eraser) .
Look trough that hole and this should permit you to read your gauge.
It's the depth of field principle used in photography. The more you close the iris the longer depth of field you have. One could even carry a piece of plastic with a small hole in it for emergencies

 

[diver 85]

I bought daily contact lenses, no big expense if I loose one while diving.
Also, in a bind, you can try making with your thumb and index the divers OK sign, but very tightly, thus leaving a very small hole (the size of a pencil eraser) .
Look trough that hole and this should permit you to read your gauge.
It's the depth of field principle used in photography. The more you close the iris the longer depth of field you have. One could even carry a piece of plastic with a small hole in it for emergencies

You're increasing the depth of field & getting rid of (some) peripheral abberations....It's the pupil(aperture) you're decreasing in size, increasing the depth of field.....