quick lens question

furby · 04-14-2008, 11:37 AM

I was just wondering if anyone knew what that white bump on older lenses is for? I doubt it has anything to do with it's functionality, but I can't figure out it's purpose.

Big Dave · 04-14-2008, 02:22 PM

furby,
When you hold the lens, before mounting, your thumb will fall just below the bump. Using the bump for reference, you can mount the lens with looking at the camera. It also can improve your grip and lessen the chance dropping the lens.

Dave

**Canada_Rockies** · 04-14-2008, 11:32 PM

Originally posted by Big Dave

furby,
When you hold the lens, before mounting, your thumb will fall just below the bump. Using the bump for reference, you can mount the lens with looking at the camera. It also can improve your grip and lessen the chance dropping the lens.

Dave

It lines up with the lens release. Some other lenses have a yellowish coloured bump instead of white.

pschlute · 04-15-2008, 12:53 AM

The FA 31 mm Ltd and FA 77mm Ltd have green bumps !!

While the 43mm Ltd doesnt have a bump at all !!

creampuff · 04-15-2008, 04:10 AM

The plastic bump is a useful index when changing lenses. Very similar to red plastic bump on Minolta MC/MD Rokkor lenses. On the Pentax it doesn't quite line up as well as the lens release button on Minolta bodies but work the same by giving a tactile reference point. Years ago when I used Minolta film cameras a lot, I could change lenses in complete darkness in seconds because I could do it by feel using the plastic bumps as a guide.

04-14-2008, 11:37 AM	#1
furby Forum Member Join Date: Jan 2008 Posts: 51	quick lens question I was just wondering if anyone knew what that white bump on older lenses is for? I doubt it has anything to do with it's functionality, but I can't figure out it's purpose.

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04-14-2008, 02:22 PM	#2
Big Dave Veteran Member Join Date: Jan 2008 Location: San Antonio, Texas Photos: Gallery Posts: 547	furby, When you hold the lens, before mounting, your thumb will fall just below the bump. Using the bump for reference, you can mount the lens with looking at the camera. It also can improve your grip and lessen the chance dropping the lens. Dave

04-14-2008, 11:32 PM	#3
Canada_Rockies Loyal Site Supporter Join Date: Nov 2007 Location: Sparwood, BC, Canada Photos: Gallery \| Albums Posts: 12,385	Originally posted by Big Dave furby, When you hold the lens, before mounting, your thumb will fall just below the bump. Using the bump for reference, you can mount the lens with looking at the camera. It also can improve your grip and lessen the chance dropping the lens. Dave It lines up with the lens release. Some other lenses have a yellowish coloured bump instead of white.

04-15-2008, 12:53 AM	#4
pschlute Moderator Loyal Site Supporter Join Date: Mar 2007 Location: Surrey, UK Photos: Gallery Posts: 8,188	The FA 31 mm Ltd and FA 77mm Ltd have green bumps !! While the 43mm Ltd doesnt have a bump at all !!

04-15-2008, 04:10 AM	#5
creampuff Veteran Member Join Date: May 2007 Location: Singapore Photos: Gallery Posts: 3,953	The plastic bump is a useful index when changing lenses. Very similar to red plastic bump on Minolta MC/MD Rokkor lenses. On the Pentax it doesn't quite line up as well as the lens release button on Minolta bodies but work the same by giving a tactile reference point. Years ago when I used Minolta film cameras a lot, I could change lenses in complete darkness in seconds because I could do it by feel using the plastic bumps as a guide.

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