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Old Jan 31, 2013, 12:35 PM
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Joined Aug 2008
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Camera Focus

Originally Posted by sparklet View Post
I found one of my original posts on focusing, at that time a "Gum Camera".

Wow ! These cameras have improved dramatically since then !

Quote from the original post....

Typical example...
Test reference photo - properties show a size of 423.6KB
Final focus adjutment a size of 493.2KB

Second reference photo 357.5KB
After final focus adjustment 455.9KB

You can see there is quite a difference in file sizes obtained during focus alterations.

If you try it then let us know how you got on.

Used above ^ method for focusing the camera,happy with the results,thanks for sharing that method.

Before trying the picture file size focus method i had just recorded video,viewed the video and made small adjustments to the lens and repeated till the video looked good.
Recording,checking,adjusting works but takes some time and you don't really have a way to actually know if the image is improving besides your eyes.
Taking a photo in the same location with the same lighting for each photo does give you the file size which enables you to get the lens focused more quickly and accurately than viewing alone.

This method works so well that you don't even need to actually view the image while conducting the focus process!

As i said the video focus was looking pretty good from taking video ,check it ect.
So decided to do the focus method based of the photo file size blind...take a photo and only noting the file size without viewing the image.
First photo...benchmark...second photo turn lens,file size decrease....third photo (turn lens back past benchmark spot file size increase.....forth photo,turn lens further from benchmark, file size decrease...fifth photo turn lens back toward benchmark,file size increase 50 over benchmark file size and left it there.

Now time to view the images and see how this blind test worked out.
They looked good and the last image was most clear.
Step outside to record a test video,come back in and view the video.
Video looks good and image is in focus better than it had been with using the record video,check,adjust lens repeat method.

If your needing to focus your camera try the photo file size comparison method,definitely gives very good results,recommend this method for anyone who needs to focus your camera.

Note:...if your concerned about the camera not being in the exact position each time you can secure the camera in position for taking photos and only remove the memory card to place in a card reader to note file size.
I did not do that but figured it is a good suggestion for those who may have trouble being sure the camera is in the exact same position for each photo.
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