The Camera Diopter

I am trying to find the most accurate way to adjust my Canon Rebel XT diopter to my eyesight. I did it using a page of a book and adjusting the diopter to see the words as sharp as possible. Even doing this, when focusing photos manually I still getting sometimes pictures out of focus or a not sharp focus.
Just for comparison, sometimes I make a manual focus of some subject and then without any movement I switch my camera to auto focus and I feel the lens making a new fine adjustment.
What can you suggest me to do or how to adjust it properly?

Tags: adjustment, camera, diopter

▶ Reply to This

Replies to This Discussion

Permalink Reply by vjekoslav antic on September 9, 2008 at 5:31am: I have the same problem as you.On my camera I have possibility to change viewfinder glass for better manual focusing.
For your camera I don't know , maybe is here who knows.I like to hear if anybody have solution for this.; ▶ Reply to This

Permalink Reply by Nivaldo on September 9, 2008 at 11:25am: Vjek;
I submitted that discussion to Canon Group and now I want to see what someone there has to tell me.
As soon I get any feedback I will forward it to you.
I now that is shame when we see things in a "sharp focus" and it came out of focus.; ▶ Reply to This

Permalink Reply by vjekoslav antic on September 9, 2008 at 11:31am: Yes,you have right I am waiting for feedback.Thanks; ▶ Reply to This

Permalink Reply by Nivaldo on September 9, 2008 at 7:20pm: Vjekoslav;
Here is a good tip that Rob sent me about the Diopter.

Permalink Reply by rob jillson 7 hours ago

I use the diopter - getting old i guess. You set the diopter by getting the LCD text that you see when you look through the range finder as sharp as possible. that text at the bottom that tells you you your f-stop, etc.... When that is sharp, then you are in focus for your eyes.

also - when you switch to auto focus, your lens will make minor adjustments even if your focus is perfect. It's not like a targeting system where when you lock on the target and then switch to auto the machine goes -"cool", I confirm you have a lock. Instead, the camera kinda focuses just like we people do. When we manually focus we rack the camera in and out of focus until we have it as sharp as possible. When the camera uses auto focus it does the same thing. In sends out it's little laser or sonic infra-red wave or whatever and then adjusts back and forth until it is on the money. So, you will always hear the lens doing that if you shift to auto out of manual.

Once you have the diopter set right, take a few pictures both manually and with auto focus. If you do this, make sure you have your auto focus set to one "point" versus all 9 points on the auto focus screen. this way the camera will be focusing on the same thing you did manually. Compare the pictures. My bet is that if you still have fuzziness, both photos will be fuzziness and your issue might be too long of a lens with too short a shutter speed or something like that.; ▶ Reply to This

Permalink Reply by rob jillson on September 9, 2008 at 11:50am: I use the diopter - getting old i guess. You set the diopter by getting the LCD text that you see when you look through the range finder as sharp as possible. that text at the bottom that tells you you your f-stop, etc.... When that is sharp, then you are in focus for your eyes.

also - when you switch to auto focus, your lens will make minor adjustments even if your focus is perfect. It's not like a targeting system where when you lock on the target and then switch to auto the machine goes -"cool", I confirm you have a lock. Instead, the camera kinda focuses just like we people do. When we manually focus we rack the camera in and out of focus until we have it as sharp as possible. When the camera uses auto focus it does the same thing. In sends out it's little laser or sonic infra-red wave or whatever and then adjusts back and forth until it is on the money. So, you will always hear the lens doing that if you shift to auto out of manual.

Once you have the diopter set right, take a few pictures both manually and with auto focus. If you do this, make sure you have your auto focus set to one "point" versus all 9 points on the auto focus screen. this way the camera will be focusing on the same thing you did manually. Compare the pictures. My bet is that if you still have fuzziness, both photos will be fuzziness and your issue might be too long of a lens with too short a shutter speed or something like that.

hope that helps; ▶ Reply to This

Permalink Reply by Nivaldo on September 9, 2008 at 7:20pm: Rob:
Thank you so much for your help about Diopter.
I found this extremelly helpful and you gave a lot of details on your reply .
I will do follow your instructions and see the difference from before and after the new adjustment.
I will forward this instructions to Vjkoslav that is facing the same problem.
Thanks again.; ▶ Reply to This