Light meter in PM

[emo supremo]

I just started using a PM to meter. However, when is set the film speed and the lowest f stop of the lens (and set the lens at the lowest f stop; wide open) I take the EV from a gray card and set my 50, 80 and 120 lenses to that EV. Result is two stops underexposed (chromes).
BUT, if i do likewise with the 150 and 250mm lenses they come out perfectly exposed.
Anybody wish to take a shot at explaining this one?

BTW. If the meter is shot is it repairable or perhaps I need to adjust it. Can the PM's meter be calibrated?

Also, I miss not having the split prisms for focusing (i.e. if focusing on a verticle edge the bottom and top line up when in focus). Is it hard/expensive to have a 500/CM modified or does this require a new body?

I need to get a separate, dependable meter to check it against.

 

[wbulte]

Also, I miss not having the split prisms for focusing (i.e. if focusing on a verticle edge the bottom and top line up when in focus). Is it hard/expensive to have a 500/CM modified or does this require a new body?

In a 500C/M you can exchange the focusing screen yourself, no problem. Remove the finder/prism, push the 2 metal retaining clips (right/left) of the screen to the sides of the camera. Then hold it upside down, catching the screen (..). Install the new screen in reverse order.

All of this is documented in the user manual (....)

Wilko

 

[polypal]

Hello Emo,


You can download a manual for your camera at: www.hasselblad.se

First register , choose a 501CM body if the 500 CM is not listed.
Fill in the body number of your camera and you have acces to all manuals at the Hasselblad site.

Regarding the problems with metering:
It is difficult without actually comparing readings against an instrument whose calibration can be trusted.

The thought crossed my mind shutterspeeds of the 50/80/120 lenses are off.
On the other hand, three lenses with the same deviation seems to much of a coincidence.
If you can have the shutters checked locally that would rule out this cause, provided they are correct.


Paul

 

[emo supremo]

I did as you suggested and registered but I had that manual & could not find anything that said a 500c/m could be upgraded to a split image glass. (my copy was a poor resolution. Thank you)

I do recall reading that it was important to orient the glass a certain way (there is an up and a down) and that those clips you refered to are supposed to snap back without any pressure or nudging.
I suppose I'll look around and give it a try.

I guess from the lack of response there is no way of tweeking the prism's meter.

I've been putting it off and I just bought myself a Voigtlander VC Meter II. I'll use this as my baseline. Perhaps it will be a simple matter of shooting my three fast lenses two stops over and the 2 longer lenses on the money.
Wierd though. I got that right don't I? You meter with the lens at 2.8 (wide open) and NOT stopped down (f22)? Yes?

 

[emo supremo]

Thanks to the Moderator, Polypal
More valuable than the camera's manual was all the others including the PM finder. Excellent info. The PM can be 'tweaked' but only by 1/2 a stop. But at least that question is cleared up. I've got to go back and reread it.
Thanks again.

 

[polypal]

It is unclear what model metering prism you are using.

The fact stays that you are having inconsistant readings/results between lenses.

Do you have the manual for the PM?
The PM needs to know the max aperture of the lens you are using to give a correct reading.
You also set the film speed before readings can be taken.

Show us what prism you are using, ihat may help to solve the problem.

Changing the screen is explained in the manual.
The way to do it was described correctly by Wilko in an earlier post.