Rear lens cap for the smaller Pentax lenses and for the DA *

Russell-Evans · 11-17-2009, 03:30 AM

I don't know if this as been posted previously, but I stumbled upon something I haven't seen before. Optech makes a couple of interesting rear lens caps. Both caps offer an O ring around the base and thus tightly seal around the rear of the lens. This will help keep the lens caps on under heavy traveling and keep dust and moisture out of the exposed rear of the lens.

What makes these really interesting is the double version of the rear lens cap.
The intended use is to make lens changes easier, but with the double you could keep a pair of small lenses in a single slot in your bag without worrying that one will be beating against the other. The 21mm with the 40mm, 43mm with the 77mm, or how about the 31m topped with the 70mm?

As anyone beat me to this and have photos of the pancakes using the double?

Thank you
Russell

Last edited by Russell-Evans; 11-17-2009 at 05:49 AM.

**dadipentak** · 11-17-2009, 06:56 AM

Very interesting--thanks!

Jodokast96 · 11-17-2009, 08:09 AM

Like the idea of the double, but I'm too cheap to pay $18 for it.

Dangermouse · 11-17-2009, 10:45 AM

You could always make one with some epoxy and a couple of cheap rear lens caps.

SOldBear · 11-17-2009, 12:08 PM

Originally posted by Russell-Evans

What makes these really interesting is the double version of the rear lens cap.

The intended use is to make lens changes easier, but with the double you could keep a pair of small lenses in a single slot in your bag without worrying that one will be beating against the other. The 21mm with the 40mm, 43mm with the 77mm, or how about the 31m topped with the 70mm?

Interestingly, the "intended use" of the double lens cap originally was NOT to make lens changes easier. The original purpose to "save storage space" in your bag, according to Op/Tech website a few months ago.

The people at Op/Tech didn't think of lens changes. About 2 months ago, I sent them an email message telling them about this thread, and that they should add the benefit of easy lens changes to their sales pitch. They then did.

I haven't been able to find any retailer that carries double lens caps for Pentax mount. If you happen to know any, please post. Thanks.

heliphoto · 11-17-2009, 12:40 PM

Cool stuff - thanks for the heads up.

Russell-Evans · 11-17-2009, 01:19 PM

Originally posted by SOldBear

I haven't been able to find any retailer that carries double lens caps for Pentax mount. If you happen to know any, please post. Thanks.

Adorama has a listing and no note about not being available or out of stock. Adorama's note thing is the worst thing about their site. Amazon says Adorama has four left.

Good for you on the quick lens change idea. You seem to have quite a number of good ideas. I always look for your posts.

Thank you
Russell

SOldBear · 11-17-2009, 01:34 PM

Originally posted by Russell-Evans

Amazon says Adorama has four left.

Thanks for the pointer to Adorama/Amazon.

But $17.95 + $6.94 shipping is pretty steep

, especially with a cheapskate like me.

Jodokast96 · 11-17-2009, 04:34 PM

Buy.com has them for $17.95 and free shipping OP/TECH LENS MOUNT CAP, DOUBLE F/PENTAX - 1101251 - Buy.com.

SOldBear · 11-17-2009, 05:09 PM

Originally posted by Jodokast96

Buy.com has them for $17.95 and free shipping OP/TECH LENS MOUNT CAP, DOUBLE F/PENTAX - 1101251 - Buy.com.

Thanks for the pointer.

I bought two copies to try out. If they are proven to be $15.50 nicer than my DIY version then I'll get some more.

I'm not sure if I should thank you for saving me $13.88 shipping cost

, or blame you for making me to spend $39.40 (including sales tax)

SOldBear · 11-24-2009, 02:50 PM

Originally posted by Russell-Evans

As anyone beat me to this and have photos of the pancakes using the double?

I didn't beat Russell to this, but I do have a photo:

Russell-Evans · 11-24-2009, 03:06 PM

That looks pretty nice. So how is getting them off and on? Can you separate the lenses with one hand? I usually have the camera in one hand, the lens to be changed to in the center slot of the bag, and get everything set up for the swap with the free hand. So is that still doable?

Thank you
Russell

SOldBear · 11-24-2009, 03:29 PM

The cap is attached to the lens with different degrees of tightness (you control how much to twist the cap on). At the greatest tightness. it's not possible for me to remove the cap with one hand. But it is doable if I don't tighten the cap too hard. A nice thing is that it's not easy for the cap to detach itself from the lens, even with a moderate degree of tightness.

However, there is a minor problem in attaching the cap to the lens: the small bump on the cap has to be aligned with the red dot on the lens. In the photo, you can see the bump on the free standing cap at 6 o'clock position and on the one attached to the lenses at 11 o'clock position. It's not as bad as some Tamron or Sigma caps because it's easy to feel the bump.

The tightness of the Op/Tech double lens cap is particularly suitable for quick lens changing because it is attached tight to the lens. My DIY double lens caps are pretty loose so I have to be careful not to drop the cap (or the lens

) in the process. There is no danger like that with the Op/Tech lens caps.

I'll keep these two caps for my Ltd lenses, and will probably buy a few more, not one for each lens, but one for each lens I carry for a photo session for fast lens swapping.

11-17-2009, 03:30 AM	#1
Russell-Evans Veteran Member Join Date: Nov 2007 Posts: 1,553	Rear lens cap for the smaller Pentax lenses and for the DA * I don't know if this as been posted previously, but I stumbled upon something I haven't seen before. Optech makes a couple of interesting rear lens caps. Both caps offer an O ring around the base and thus tightly seal around the rear of the lens. This will help keep the lens caps on under heavy traveling and keep dust and moisture out of the exposed rear of the lens. What makes these really interesting is the double version of the rear lens cap. The intended use is to make lens changes easier, but with the double you could keep a pair of small lenses in a single slot in your bag without worrying that one will be beating against the other. The 21mm with the 40mm, 43mm with the 77mm, or how about the 31m topped with the 70mm? As anyone beat me to this and have photos of the pancakes using the double? Thank you Russell Last edited by Russell-Evans; 11-17-2009 at 05:49 AM.

11-24-2009, 02:50 PM	#11
SOldBear Veteran Member Join Date: Feb 2009 Location: Alameda, CA Posts: 3,206	Originally posted by Russell-Evans As anyone beat me to this and have photos of the pancakes using the double? I didn't beat Russell to this, but I do have a photo: Last edited by SOldBear; 07-20-2010 at 01:26 PM.

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11-17-2009, 06:56 AM	#2
dadipentak Site Supporter Join Date: Jul 2008 Location: Baltimore, Maryland Photos: Gallery Posts: 11,590	Very interesting--thanks!

11-17-2009, 08:09 AM	#3
Jodokast96 Veteran Member Join Date: Oct 2007 Location: Erial, NJ USA Photos: Gallery \| Albums Posts: 2,134	Like the idea of the double, but I'm too cheap to pay $18 for it.

11-17-2009, 10:45 AM	#4
Dangermouse Senior Member Join Date: Oct 2009 Posts: 283	You could always make one with some epoxy and a couple of cheap rear lens caps.

11-17-2009, 12:08 PM	#5
SOldBear Veteran Member Join Date: Feb 2009 Location: Alameda, CA Posts: 3,206	Originally posted by Russell-Evans What makes these really interesting is the double version of the rear lens cap. The intended use is to make lens changes easier, but with the double you could keep a pair of small lenses in a single slot in your bag without worrying that one will be beating against the other. The 21mm with the 40mm, 43mm with the 77mm, or how about the 31m topped with the 70mm? Interestingly, the "intended use" of the double lens cap originally was NOT to make lens changes easier. The original purpose to "save storage space" in your bag, according to Op/Tech website a few months ago. The people at Op/Tech didn't think of lens changes. About 2 months ago, I sent them an email message telling them about this thread, and that they should add the benefit of easy lens changes to their sales pitch. They then did. I haven't been able to find any retailer that carries double lens caps for Pentax mount. If you happen to know any, please post. Thanks.

11-17-2009, 12:40 PM	#6
heliphoto Veteran Member Join Date: May 2008 Location: Region 5 Photos: Gallery Posts: 2,539	Cool stuff - thanks for the heads up.

11-17-2009, 01:19 PM	#7
Russell-Evans Veteran Member Join Date: Nov 2007 Posts: 1,553 Original Poster	Originally posted by SOldBear I haven't been able to find any retailer that carries double lens caps for Pentax mount. If you happen to know any, please post. Thanks. Adorama has a listing and no note about not being available or out of stock. Adorama's note thing is the worst thing about their site. Amazon says Adorama has four left. Good for you on the quick lens change idea. You seem to have quite a number of good ideas. I always look for your posts. Thank you Russell

11-17-2009, 01:34 PM	#8
SOldBear Veteran Member Join Date: Feb 2009 Location: Alameda, CA Posts: 3,206	Originally posted by Russell-Evans Amazon says Adorama has four left. Thanks for the pointer to Adorama/Amazon. But $17.95 + $6.94 shipping is pretty steep , especially with a cheapskate like me.

11-17-2009, 04:34 PM	#9
Jodokast96 Veteran Member Join Date: Oct 2007 Location: Erial, NJ USA Photos: Gallery \| Albums Posts: 2,134	Buy.com has them for $17.95 and free shipping OP/TECH LENS MOUNT CAP, DOUBLE F/PENTAX - 1101251 - Buy.com.

11-17-2009, 05:09 PM	#10
SOldBear Veteran Member Join Date: Feb 2009 Location: Alameda, CA Posts: 3,206	Originally posted by Jodokast96 Buy.com has them for $17.95 and free shipping OP/TECH LENS MOUNT CAP, DOUBLE F/PENTAX - 1101251 - Buy.com. Thanks for the pointer. I bought two copies to try out. If they are proven to be $15.50 nicer than my DIY version then I'll get some more. I'm not sure if I should thank you for saving me $13.88 shipping cost , or blame you for making me to spend $39.40 (including sales tax)

11-24-2009, 03:06 PM	#12
Russell-Evans Veteran Member Join Date: Nov 2007 Posts: 1,553 Original Poster	That looks pretty nice. So how is getting them off and on? Can you separate the lenses with one hand? I usually have the camera in one hand, the lens to be changed to in the center slot of the bag, and get everything set up for the swap with the free hand. So is that still doable? Thank you Russell

11-24-2009, 03:29 PM	#13
SOldBear Veteran Member Join Date: Feb 2009 Location: Alameda, CA Posts: 3,206	The cap is attached to the lens with different degrees of tightness (you control how much to twist the cap on). At the greatest tightness. it's not possible for me to remove the cap with one hand. But it is doable if I don't tighten the cap too hard. A nice thing is that it's not easy for the cap to detach itself from the lens, even with a moderate degree of tightness. However, there is a minor problem in attaching the cap to the lens: the small bump on the cap has to be aligned with the red dot on the lens. In the photo, you can see the bump on the free standing cap at 6 o'clock position and on the one attached to the lenses at 11 o'clock position. It's not as bad as some Tamron or Sigma caps because it's easy to feel the bump. The tightness of the Op/Tech double lens cap is particularly suitable for quick lens changing because it is attached tight to the lens. My DIY double lens caps are pretty loose so I have to be careful not to drop the cap (or the lens ) in the process. There is no danger like that with the Op/Tech lens caps. I'll keep these two caps for my Ltd lenses, and will probably buy a few more, not one for each lens, but one for each lens I carry for a photo session for fast lens swapping.