Mamiya Six Lens Calibrating / Collimating

T

tonyc

Established
Local time
9:20 PM
Joined
Mar 15, 2007
Messages
125
View My Gallery
Hello

I have noticed my Mamiya Six Automat
focuses past infinity.

Does anyone know how to adjust the lens ?
Or perhaps it is the backfocus mechanism,
although I can't see any adjustment for this.

I have found some people insert spacers behind
the front element to do this, but on the automat
model this is not possible as the shutter cock device
spins behind the front element and would become
squeezed or blocked by the spacers.

-tc
 
I am sure someone who has done this will come in and comment. I don't have mine here to look at, but could you not at least put a spacer behind the frame and the bellows? it would be harder to check before recementing of course.
 
oftheherd said:
I am sure someone who has done this will come in and comment. I don't have mine here to look at, but could you not at least put a spacer behind the frame and the bellows? it would be harder to check before recementing of course.
Click to expand...

Hello
Thanks for the reply.

Do you mean taking off the shutter assembly and
put in the spacer between this and the frame ?

-tc
 
That was indeed what I meant. However, I had a chance to look at mine last night. I don't know if we have the same model. However, on mine, it appears the bellows attaches to the frame, and the entire lens assembly screws in and out of the frame. If that is so on yours, and you are sure you need to adjust your lens distance from the film plane, that would seem to be the way to do it.

Just for curiosity's sake, does your Mamiya otherwise focus correctly? That is, is it focusing correctly at close distances and at infinity, even if it can also focus past infinity? If so, I would not bother with it. Focus as the focusing mechanism dictates, and take nice photos.
 
oftheherd said:
Just for curiosity's sake, does your Mamiya otherwise focus correctly? That is, is it focusing correctly at close distances and at infinity, even if it can also focus past infinity? If so, I would not bother with it. Focus as the focusing mechanism dictates, and take nice photos.
Click to expand...

+1 on that
 
sper said:
It's supposed to focus past infinity. Something to do with compensating for temperature changes.
Click to expand...

I had thought of that but then didn't think it would apply to an old folder. They are built differently from say a long 35mm lens, which might need that feature. They tend to come out to an infinity stop, and I wouldn't have thought heat would have effected that so much.

Are you sure on that, or thinking of 35mm lenses? Good to know if true.
 
oftheherd said:
That was indeed what I meant. However, I had a chance to look at mine last night. I don't know if we have the same model. However, on mine, it appears the bellows attaches to the frame, and the entire lens assembly screws in and out of the frame. If that is so on yours, and you are sure you need to adjust your lens distance from the film plane, that would seem to be the way to do it.
.
Click to expand...

Hello
Thanks for the help.

I will look into that.
First film test dosent look too bad, but it does
focus a bit behind the chosen focus point.

I will try again.

My main worry was that I mostly shoot infinity for
landscape etc, and wanted to be sure it was sharp.

-tc
 
You must log in or register to reply here.
Back
Top Bottom