At 77-years old, I am still going strong. I am healthy, weigh 180 pounds at six feet one inch tall, my blood pressure hovers around 130 over 70 and my cholesterol is way down there. However, my vision is not as acute as it once was. Although I don't need glasses for distance work, my closeup ability is lacking and I often have problems with extreme variations in light'
Hence my problems shooting with the Canon 7D Mark ii. Although I do love this camera, I have been experiencing difficulties reading the information at the bottom and sides of the frame. I was especially having difficulty reading the exposure level bar at the right side of the frame.
This eyecup has solved those difficulties.
https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1
It shades my viewfinder from ambient light and allows me to easily read the information in the frame. It is also quite comfortable to use. Although I am left eyed, I can also use this eyecup sighting with my right eye. It also works with sunglasses. I have a pair of non prescription, non polarized sunglasses that have an over the counter bifocal reading field.