NavList:

My age 78 has caught up with my eyes which were very similar two yours and have worn glasses almost as long as you have. My good fortune was I had to have cataract surgery now I have 20/20 vision. That might be an option for you. The other option is what many gun shooters do is have a corrected lense made to fit in your optical piece that fits as  the first glass you  look through  both kind of pricey but a one time fix.

Welcome, Mark.

When the vessel is rolling a lot, it sometimes seems impossible to bring down a body when it is abeam. I remove the telescope and put it in a pocket. This gives a very wide field of view and when the body is approximately on the horizon I replace the telescope and pick up the body easily by sweeping the horizon. This works best with modern sextants that have a simple vee and flat rising piece, though some Admiralty pattern Hughes and Son sextants were fitted with interrupted threads to the telescopes to amke rapid assembly possible.

When using a micrometer sextant, steady the limb with the left index finger while twiddling the thimble with thumb and middle finger. It takes some of the strain off the right hand and steadies the sextant.

Wear your (quartz) navigating watch of known error and always reading GMT on the inside of your right wrist so you can read it immediately. If without a note-taker, then swap hands (if right-handed) and note the time and altitude on a piece of frosted plastic glued to the outside of the handle.

If a spectacle-wearer, protect your glasses with a piece of wash-leather attached to the eyepiece of the telescope (https://sextantbook.com/?s=scopes+for+myopes ). If you take off your specs to take a sight, hold one temporal between your teeth, so the specs are immediately available if necessary to read the sextant. Commander Bauer recommended using an oldish pair with one lens removed for sight taking, but it didn't work for me as the 'scope kept fouling the frame.

Bill Morris

Pukenui

New Zealand