Pentax MX half-press turn on meter?

[newfilm]

Hello,

So... I got myself a Pentax MX (my dad uses one in the 80s) and my childhood memory of having to join two half circle into one full circle in the viewfinder is some what nostalgic, so I just brought a used one to add to the collections 🙂

Anyway, playing around with it I notice something peculiar, I though that if I push the lever against the body would turn the light meter off? Right now, the only way for me to turn the light meter off is by turning the shutter button to "Lock" mode, I remember lesson from the 80s from my dad is:

1. winding lever pull out -> half press shutter button light meter will stay On even you lift your finger away from the shutter button.
2. winding lever push in -> half press shutter button light meter will stay On until you lift your finger from the shutter button.

But right now.... as long as I half press the shutter button (after I unlock the shutter button from Lock position), the light meter turn On and stay On, regardless of the winding lever position, only way to turn it off would be turn the shutter lock to "Lock", I wonder... if anyone who also have a Pentax MX verify what would be a "normal" behaviour of it? Many thanks!


Edit:
Ok, I open up the top plate, and attached a picture here. I notice there is a "lever" (as highlight in yellow arrow in the picture) will hold the shutter button down in half-press mode, the action of twisting the shutter Lock (when the top plate is in place) will push this lever out of the way hence the half press shutter will pop back up. Now, can any one confirm if this lever (mark by the yellow arrow in the picture) should also move out of the way if the file advance lever is in parked position?

 

[sevo]

It should be "pull the lever AND half-press the release" - the lever locks the rod that actuates the meter switch in the camera base (you might be able to abuse it to lock the meter in on position as well, but that is not officially documented).

The locking mechanism may have worn out, or it may have been removed (some people disliked extra locks on the camera operation).

 

[ronnies]

I think this is a common MX problem with the meter contacts under the base plate. The spring pushing the shutter button up may not be pushing it enough to break the contact but when you lock the release the button gets lifted again slightly and breaks the contact.

Ronnir

 

[kb244]

Hrm something I'll have to check out when I receive mine this week sometimes. Cept mine has been recently fully CLA'd.

 

[Dan Daniel]

I can't locate it now, but I've seen this porblem described on the web. As said, if you remove the baseplate you'll see the meter switch at the end of a rod connected to the shutter release button. I think it was a matter of either cleaning this switch or maybe giving the metal plate a bit of a pull so it actually separates enough to turn off properly?

Oh, wait- here: http://no-exif.com/2011/07/24/pentax-mx-meter-fix/

And:
http://www.geocities.ws/spirope/mxmlu.html
https://www.flickr.com/groups/32373122@N00/discuss/72157622720330681/

 

[kb244]

I can't locate it now, but I've seen this porblem described on the web. As said, if you remove the baseplate you'll see the meter switch at the end of a rod connected to the shutter release button. I think it was a matter of either cleaning this switch or maybe giving the metal plate a bit of a pull so it actually separates enough to turn off properly?

Oh, wait- here: http://no-exif.com/2011/07/24/pentax-mx-meter-fix/

And:
http://www.geocities.ws/spirope/mxmlu.html
https://www.flickr.com/groups/32373122@N00/discuss/72157622720330681/

I'm bookmarking that for later, I doubt I'll have to do it for my CLA'd one any time soon, but if the problem does pop up, I'll know where to look.

 

[newfilm]

I think this is a common MX problem with the meter contacts under the base plate. The spring pushing the shutter button up may not be pushing it enough to break the contact but when you lock the release the button gets lifted again slightly and breaks the contact.

Ronnir

Em... I have the opposite problem, the contact is working, its just that the only way to turn it Off after half-press that activate the meter I have to turn the shutter collar to Lock to turn it off, which I felt a little different from what I remember.

p/s: I opened up the top plate, and updated the first post with pic maybe that'll shed some light if some thing is off with my copy of pentax mx...

 

[ronnies]

Em... I have the opposite problem, the contact is working, its just that the only way to turn it Off after half-press that activate the meter I have to turn the shutter collar to Lock to turn it off, which I felt a little different from what I remember.

p/s: I opened up the top plate, and updated the first post with pic maybe that'll shed some light if some thing is off with my copy of pentax mx...

No you don't. At least not as you described it in the first post. 🙂 The meter switch is at the bottom of the shutter button mechanism under the base plate. Pulling the windon lever out just holds the shutter button down a little to make contact. When you push the wind on lever flush again the button should pop up a little and break contact. Yours isn't popping up enough but perhaps the shutter lock is lifting it a little more and just enough to break the contact.

What i described is the meter staying on when it should have gone off (breaking the contact).

Ronnie