Posted by Howard Cihak on July 11, 2011 at 7:21 PM
Autofocus isn't really "sharp" focus, so manual focusing is most desirable. Manual focusing isn't much good if your vision isn't.
I use my right eye to see through the viewfinder, and my right eye is near-sighted and astigmatic. Using glasses pressed against the eyepiece is frustrating because then I can't see the entire viewfinder screen.
Has anyone ever heard, or know of, someone who can custom grind to a prescription a lens to fit over the eyepiece of a Canon DSLR? That would be the answer to my problems.
P.S. Don't suggest trying to use my left eye. Been there, done that, gave up.
"Autofocus isn't really "sharp" focus, so manual focusing is most desirable."
I don't find this to be the case at all. If you're experiencing this problem with autofocus, then you should consider using the microfocus lens adjustment feature (in concurrence with LiveView) in your camera.
Also, Live View zoomed in to the max. is a much more accurate way of obtaining critical manual focusing than any camera viewfinder could hope to be. Are you experiencing problems using LiveView, as well?
I have astigmatism and I need reading glasses bad enough that I keep them hanging around my neck (librarian-style) a lot of the time and the Hoodman loop makes using Live View a real pleasure. It has a diopter adjustment of +/- 3 that works great. I just twist the diopter adjuster until the settings at the bottom of the screen are clear, then I manually focus the lens.
Also, the standard Canon eyepiece has a diopter adjustment wheel too. (Upper right side of viewfinder) Since I always shoot from a tripod and love Live View, I haven't messed with the built-in diopter.
You might also consider sending your lenses and body to Canon for adjustment. They will clean and adjust each individually, then pair all of your Canon lenses with your camera body and make any corrections necessary to the auto focus (and all other communications between the lens and the body).
Posted by Howard Cihak on July 12, 2011 at 1:47 AM
John, the problem isn't magnification, it's the fact that, at any magnification my right eye does not focus all the colors at the same point. This means that even the sharpest focus still appears to be a slight blur to me. The diopter adjustment can offset, to some degree, near or far sightedness in the eyepiece, but it cannot offset astigmatism.
CAZ, what does Canon charge for the service you described?
Howard - Jim Talaric is the guy who knows everything about working with Canon on that type of thing. Do a search for "talaric" using the "Search this Forum" feature above for his email. Feel free to tell him I suggested you contact him.
"You might also consider sending your lenses and body to Canon for adjustment. They will clean and adjust each individually, then pair all of your Canon lenses with your camera body and make any corrections necessary to the auto focus."
Just a note to remind you that this can be done for free in the privacy of your own home using the microfocus lens adjustment feature in your camera.
OK John - How about one of the now-famous "Mumaw Tutorials"? Or is this another one of those things best explained in the desert, at night, with ice-cold micro brews?
Why....everything is best explained in the desert at night with an ice cold microbrew, CAZ!
However, the second best method is following this tutorial at Northlght Images. The lens microadjustment feature can be found in the Custom Function menu of the 5DII.
Posted by Howard Cihak on July 13, 2011 at 2:12 PM
Alas, I no longer have a 5D2. The day after our get-together in Moab in May, I was hiking in Arches when the water reservoir in my backpack sprang a leak. It well and truly soaked my 5D2 before I had a clue of what was happening. Fortunately, my lens escaped. The cost of repair the 5D2 was about the same as buying a new one. I had to finish the my trip using my G11 (that's what I used for my shots at GSD and the halo cloud over the Sangres de Christo range).
I recently bought a 60D as my temporary main body. I expect to replace the 5D2 and then carry the 60D as my back-up (I've learned my lesson). Frankly, I've decided to wait for the 5D3 in hopes it will incorporate some of the nice features now in the 60D (button activation of live view, articulating LCD screen, in camera level indicator). Unfortunately, the 60D doesn't feature micro-focusing.
Oh, and John, as an Easterner, let me tell you that EVERYTHING is better in the desert at night with ANY ice-cold brew!
Discussion
9 repliesI use my right eye to see through the viewfinder, and my right eye is near-sighted and astigmatic. Using glasses pressed against the eyepiece is frustrating because then I can't see the entire viewfinder screen.
Has anyone ever heard, or know of, someone who can custom grind to a prescription a lens to fit over the eyepiece of a Canon DSLR? That would be the answer to my problems.
P.S. Don't suggest trying to use my left eye. Been there, done that, gave up.
Also, Live View zoomed in to the max. is a much more accurate way of obtaining critical manual focusing than any camera viewfinder could hope to be. Are you experiencing problems using LiveView, as well?
Also, the standard Canon eyepiece has a diopter adjustment wheel too. (Upper right side of viewfinder) Since I always shoot from a tripod and love Live View, I haven't messed with the built-in diopter.
You might also consider sending your lenses and body to Canon for adjustment. They will clean and adjust each individually, then pair all of your Canon lenses with your camera body and make any corrections necessary to the auto focus (and all other communications between the lens and the body).
CAZ, what does Canon charge for the service you described?
However, the second best method is following this tutorial at Northlght Images. The lens microadjustment feature can be found in the Custom Function menu of the 5DII.
I recently bought a 60D as my temporary main body. I expect to replace the 5D2 and then carry the 60D as my back-up (I've learned my lesson). Frankly, I've decided to wait for the 5D3 in hopes it will incorporate some of the nice features now in the 60D (button activation of live view, articulating LCD screen, in camera level indicator). Unfortunately, the 60D doesn't feature micro-focusing.
Oh, and John, as an Easterner, let me tell you that EVERYTHING is better in the desert at night with ANY ice-cold brew!