New XS lens has strange groove/hole at K-mount

konraDarnok · 02-12-2012, 01:33 PM

These are speed holes, they make the lens go faster.

bwDraco · 02-12-2012, 01:34 PM

Perhaps this is a modification of the K mount similar to the Canon EF-S mount?

N.B. The Canon EF-S mount is an extension of the EF mount which is exclusive to APS-C lenses and bodies. An EF-S body can take both EF and EF-S lenses, but an EF body cannot accept EF-S lenses. EF-S lenses often have protruding rear elements that will collide with a full-frame mirror.

--DragonLord

Painter · 02-12-2012, 02:18 PM

The prototype may not be machined to the same level as the final product would be and it could even be a different material.

Originally posted by Asahiflex

It's certainly aluminium:

Asahiflex · 02-12-2012, 02:47 PM

Originally posted by ogl

What is it? It's only one photo where we can see it.

An important clue is that this is the smallest lens ever (at least for the K-mount). This means less space for certain mechanisms such as the diaphragm actuation. IMHO the opening provides just that: more space for the lens mechanism.

frank · 02-12-2012, 07:55 PM

Originally posted by Painter

The prototype may not be machined to the same level as the final product would be and it could even be a different material.

This might be the reason, 'cause most if not all 40XS photos are from prototypes but not the actual final production copies.

openyourap · 02-13-2012, 02:31 AM

The small size might also be a challenge in assembly. The hole might play a role in connecting the actuator arm with the aperture mechanism.

Blue · 02-13-2012, 08:37 AM - **2 Likes**

It could be the ogl hole. Pentax engineers devised the ogl hole to keep him busy for a while.

johnmflores · 02-13-2012, 08:42 AM

Originally posted by Blue

It could be the ogl hole. Pentax engineers devised the ogl hole to keep him busy for a while.

LOgL!

eurostar · 02-13-2012, 08:47 AM

Originally posted by blue

it could be the ogl hole. Pentax engineers devised the ogl hole to keep him busy for a while.

ogl · 02-13-2012, 08:53 AM

Originally posted by Blue

It could be the ogl hole. Pentax engineers devised the ogl hole to keep him busy for a while.

My hole is in other place...

bogiesbad · 02-13-2012, 07:02 PM

Originally posted by rvannatta

If they make a lens that protrudes so far that you smash the mirror just trying to install it, then we will probably have a lot of broken mirrors.

Unlucky to say the least and would probably reflect badly on Pentax.

JinDesu · 02-13-2012, 07:10 PM

Originally posted by bogiesbad

Unlucky to say the least and would probably reflect badly on Pentax.

Is that a pun

?

bogiesbad · 02-13-2012, 07:15 PM

Originally posted by JinDesu

Is that a pun

?

Just one way to state the obvious.

**felixkh** · 02-14-2012, 06:54 AM

Originally posted by aleonx3

Me too, don't see anything strange about it, there is always hole around the aperture level.

By the way, does the 40mm XS lens mounts properly on the k-5? I like to give it a try if it is priced similarly to the DA 40.

How about a Limited Edition Silver K5 with silver DA40XS?

Ubuntu_user · 02-14-2012, 09:06 AM

Originally posted by felixkh

How about a Limited Edition Silver K5 with silver DA40XS?

That image looks stimulated.

02-12-2012, 02:18 PM	#18
Painter Veteran Member Join Date: Jun 2008 Location: Canada Photos: Gallery Posts: 348	may be just the material used for prototyping The prototype may not be machined to the same level as the final product would be and it could even be a different material. Originally posted by Asahiflex It's certainly aluminium:

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02-12-2012, 01:33 PM	#16
konraDarnok Veteran Member Join Date: Aug 2007 Photos: Albums Posts: 969	These are speed holes, they make the lens go faster.

02-12-2012, 01:34 PM	#17
bwDraco Veteran Member Join Date: Jul 2010 Location: New York Photos: Albums Posts: 1,071	Perhaps this is a modification of the K mount similar to the Canon EF-S mount? N.B. The Canon EF-S mount is an extension of the EF mount which is exclusive to APS-C lenses and bodies. An EF-S body can take both EF and EF-S lenses, but an EF body cannot accept EF-S lenses. EF-S lenses often have protruding rear elements that will collide with a full-frame mirror. --DragonLord

02-12-2012, 02:47 PM	#19
Asahiflex Pentaxian Join Date: Jan 2008 Location: Netherlands Photos: Gallery Posts: 2,795	Originally posted by ogl What is it? It's only one photo where we can see it. An important clue is that this is the smallest lens ever (at least for the K-mount). This means less space for certain mechanisms such as the diaphragm actuation. IMHO the opening provides just that: more space for the lens mechanism.

02-12-2012, 07:55 PM	#20
frank Veteran Member Join Date: Nov 2006 Location: Singapore Photos: Gallery Posts: 3,202	Originally posted by Painter The prototype may not be machined to the same level as the final product would be and it could even be a different material. This might be the reason, 'cause most if not all 40XS photos are from prototypes but not the actual final production copies.

02-13-2012, 02:31 AM	#21
openyourap Senior Member Join Date: Jun 2009 Location: Sydney Photos: Gallery \| Albums Posts: 171	The small size might also be a challenge in assembly. The hole might play a role in connecting the actuator arm with the aperture mechanism.

02-13-2012, 08:37 AM - 2 Likes	#22
Blue Moderator Site Supporter Join Date: Jun 2008 Location: Florida Hill Country Photos: Gallery \| Albums Posts: 17,377	It could be the ogl hole. Pentax engineers devised the ogl hole to keep him busy for a while.

02-13-2012, 08:42 AM	#23
johnmflores Veteran Member Join Date: Apr 2009 Location: Somerville, NJ Photos: Gallery \| Albums Posts: 5,361	Originally posted by Blue It could be the ogl hole. Pentax engineers devised the ogl hole to keep him busy for a while. LOgL!

02-13-2012, 08:47 AM	#24
eurostar Veteran Member Join Date: Dec 2006 Location: Albareto, Italy Photos: Gallery Posts: 819	Originally posted by blue it could be the ogl hole. Pentax engineers devised the ogl hole to keep him busy for a while.

02-13-2012, 08:53 AM	#25
ogl Banned Join Date: Dec 2007 Location: Sankt Peterburg Photos: Gallery \| Albums Posts: 8,382 Original Poster	Originally posted by Blue It could be the ogl hole. Pentax engineers devised the ogl hole to keep him busy for a while. My hole is in other place...

02-13-2012, 07:02 PM	#26
bogiesbad Veteran Member Join Date: Dec 2008 Location: Lower AL Photos: Albums Posts: 355	Originally posted by rvannatta If they make a lens that protrudes so far that you smash the mirror just trying to install it, then we will probably have a lot of broken mirrors. Unlucky to say the least and would probably reflect badly on Pentax.

02-13-2012, 07:10 PM	#27
JinDesu Veteran Member Join Date: Jun 2011 Location: New York City Photos: Gallery Posts: 5,638	Originally posted by bogiesbad Unlucky to say the least and would probably reflect badly on Pentax. Is that a pun ?

02-13-2012, 07:15 PM	#28
bogiesbad Veteran Member Join Date: Dec 2008 Location: Lower AL Photos: Albums Posts: 355	Originally posted by JinDesu Is that a pun ? Just one way to state the obvious.

02-14-2012, 06:54 AM	#29
felixkh Site Supporter Join Date: Nov 2008 Location: Singapore Photos: Gallery Posts: 1,201	Originally posted by aleonx3 Me too, don't see anything strange about it, there is always hole around the aperture level. By the way, does the 40mm XS lens mounts properly on the k-5? I like to give it a try if it is priced similarly to the DA 40. How about a Limited Edition Silver K5 with silver DA40XS?

02-14-2012, 09:06 AM	#30
Ubuntu_user Veteran Member Join Date: Mar 2010 Photos: Gallery \| Albums Posts: 1,545	Originally posted by felixkh How about a Limited Edition Silver K5 with silver DA40XS? That image looks stimulated.