Today’s Question: Regarding manual focus: You reference using the live view to focus when wearing glasses, but any hints for those of us who wear progressive lenses? I’m never sure what part of the glasses lens I’m looking through, so the focus is often not very sharp. Should I just get tri-focal lenses for photography?
Tim’s Quick Answer: Depending on your vision prescription, you may be able to avoid glasses altogether when photographing by adjusting the diopter on your camera’s viewfinder (if it is so equipped). You could also opt for eyeglasses that do not have progressive lenses when you are photographing.
More Detail: I too have eyeglasses with progressive lenses and find it difficult to make sure I’m looking through the right portion of the lenses when evaluating sharpness. When using the LCD in Live View mode, I can use the text on the display to help make sure I’m looking through the right portion of the glasses. If the text looks sharp, then I’m looking through the right portion to evaluate the rest of the image preview.
If you prefer to use the viewfinder, a diopter adjustment may provide a solution. If your camera has a diopter, you can apply an adjustment so the view is in focus when you aren’t wearing your glasses. As long as your vision prescription isn’t too strong, this can provide a good solution.
Another option might be to use reading glasses with a single correction factor (not progressive lenses) when photographing, assuming that is an option for you based on your prescription. This would enable you to have a single vision correction that would be suitable for evaluating focus based on the camera’s LCD display.
Trifocal (or even bifocal) lenses would be a good idea if the above didn’t work, since the lack of blending for the focus zones on the lenses would make it easier to know when you’re looking through the correct portion of the lens. This would make it possible, for example, to use one portion of the lens for evaluating focus on the camera’s LCD display, and another portion for evaluating distant focus through the viewfinder.