Pentax lens dot

[MFstooges]

Does anyone know what function is served by the Pentax lens white dot? You know that round plastic looking sphere? What happens if it fell off?

 

[xkaes]

Read the manual. It is used to align the lens to the dot on the body.

 

[MFstooges]

Thank you. I don't have the manual.
Noted it's basically cosmetic function.

 

[Philippe-Georges]

It's very handy when changing lenses in a haste, or in subbed light; you can feel by that white little half ball where and how to alight the lens while keeping an eye on the subject's situation.

The body's bayonet's starting point is somewhere in the middle between the mirror up lever and the underside of the camera, where the lens's unlock button is, and is marked with a red dot on that bayonet (which isn't so easy to see).

On the Leica lenses it's red little half ball...

 

[MFstooges]

It's very handy when changing lenses in a haste, or in subbed light; you can feel by that white little half ball where and how to alight the lens while keeping an eye on the subject's situation.

The body's bayonet's starting point is somewhere in the middle between the mirror up lever and the underside of the camera, where the lens's unlock button is, and is marked with a red dot on that bayonet (which isn't so easy to see).

On the Leica lenses it's red little half ball...

Thanks. I am thinking to purchase a beat up Pentax which lost the dot (hence why this question is posted in camera building and repairs forum). If the purpose is just that then it's not critical.

 

[cmacd123]

I worked behind a camera counter when those came out. we had to practice switching lenses behind our back using the White dot. it is aligned with the lens release button to install the lens.
Pentax was concerned that existing customers would be taken aback when they had to suddenly align the lens to swap lenses. (previously some M42 customers where always woried about the posiblity of cross threading the screw mount lenses.)

some other brands use a raised RED dot to make it easy to find where the lens should be placed, with the dot on the body at the 12 o'clock position.

 

[Bill Burk]

Thanks. I am thinking to purchase a beat up Pentax which lost the dot (hence why this question is posted in camera building and repairs forum). If the purpose is just that then it's not critical.

at that rate you could glue or paint on any old dot

 

[Philippe-Georges]

Thanks. I am thinking to purchase a beat up Pentax which lost the dot (hence why this question is posted in camera building and repairs forum). If the purpose is just that then it's not critical.

You will be surprised how good a wel taken care of Pentax lens performs (I can't speak for the zoomlenses).

Long time ago, I had a Pentax LX workhorse stable which performed excellently...

 

[beemermark]

Thank you. I don't have the manual.
Noted it's basically cosmetic function.

Pentax manuals - https://butkus.org/chinon/pentax.htm