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Message |
    
Gouranga
Tinkerer
Username: Gouranga
Post Number: 26
Registered: 01-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, July 24, 2012 - 07:58 am: | 
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Hey,
I recently picked up a mamiya C220, but I've found out that the focus at infinity is off.
When you turn the focus knob to the furthest setting (which should be infinity), it is actually focused slightly past infinity. Obviously this shouldn't be the case..
Does anyone have an idea of how to adjust the knob so that it locks off at the correct infinity setting?
Cheers! |
Paul_ron
Tinkerer
Username: Paul_ron
Post Number: 302
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, July 25, 2012 - 06:52 am: |
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The focus after infinity can be either the viewing lens is off or the screen is not focused properly. Do yuo wear reading glasses?... diopter is another cause.
Take the lens off n look through while pointing the camera at a blank wall. Are the screen etchings or grid in focus? If not you need a diopter to adjust for your eyes.
Check to see if the viewing n taking lens agree by checking it against a well lit target while on a tripod.
Set the focus on the screen then check the film plane focus using a ground glass over the film gate. I like to use a loupe to inspect the results so I can be sure I am razor sharp in focus.
If the taking lens doesn't agree, the adjustment will be at the screen. By raising or lowering it to comepnsate for the difference. If there is no adjustment on your model then the viewing lens wil have to be adjusted by unscrewing it or screwing it in to make up the difference.
I check my focus adjustments using a collimeter but there are ways you can make one very easily. Look it up on Google as a DIY collimeter.
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Brcamera
Tinkerer
Username: Brcamera
Post Number: 188
Registered: 08-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, July 26, 2012 - 04:43 pm: |
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The bellows on Mamiya twin lens cameras have different infinity spots depending on what lens you are using. So the bellows cranked all the way back would not be infinity for most lenses. There is a scale on the side of the camera that shows what your focus distance is for the different focal length lenses. As long as your taking lens and viewing lens are tracking, you will be fine. There is no "hard" infinity position for the bellows as you find on 35mm SLR cameras. |
