SMC K 85mm 1.8 Slow Aperture Blades

Eric4 · 05-06-2018, 02:09 PM

Greetings. It seems as though my 85 1.8 has some lethargic aperture blades. They look to be free of oil, so perhaps its an old spring? Has anyone needed to repair this lens in the past for the same issue? I'm wondering if this will require an expert, or if I can DIY the repair.

Cheers!
Eric

Not a Number · 05-06-2018, 03:07 PM

Given the price that these lenses can get on the used market I wouldn't attempt a DIY repair unless one has experience in working on lenses.

Try Eric Hendrickson Home-Pentaxs or @dcshooter for CLA / Repairs.

**ChrisPlatt** · 05-06-2018, 03:39 PM - **1 Like**

Usually this occurs because grease from the focusing helical liquefies
and deposits on the diaphragm blades. Often it is not visible.

I too would not recommend a DIY repair on such a pricey lens.
Send it to Eric. Tomorrow I'm sending him an M35/2.8 lens for the same problem.

Chris

**gofour3** · 05-06-2018, 05:59 PM

Originally posted by ChrisPlatt

I too would not recommend a DIY repair on such a pricey lens.
Send it to Eric. Tomorrow I'm sending him an M35/2.8 lens for the same problem.

+1 yep Eric fixed my K85/1.8 which had the same issue as the OP's lens.

Phil.

Eric4 · 05-07-2018, 08:02 AM

Thanks for the recommendations everyone. I'll get a quote from Eric on the repair. My copy of the lens is quite clean, so it's worth having a professional deal with it.

leicaman · 07-11-2018, 12:55 PM

Yes Eric is very good. I just got back from him a vintage Spotmatic F on which he did a wonderful job. In my real job I am a professional photographer with many years of experience with all sorts of repair people. I shoot film on days off for pleasure and nostalgic effect.

05-06-2018, 02:09 PM	#1
Eric4 Junior Member Join Date: Jul 2015 Location: Napa, CA Posts: 33	SMC K 85mm 1.8 Slow Aperture Blades Greetings. It seems as though my 85 1.8 has some lethargic aperture blades. They look to be free of oil, so perhaps its an old spring? Has anyone needed to repair this lens in the past for the same issue? I'm wondering if this will require an expert, or if I can DIY the repair. Cheers! Eric

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05-06-2018, 03:07 PM	#2
Not a Number Moderator Join Date: Mar 2012 Location: Venice, CA Posts: 10,322	Given the price that these lenses can get on the used market I wouldn't attempt a DIY repair unless one has experience in working on lenses. Try Eric Hendrickson Home-Pentaxs or @dcshooter for CLA / Repairs.

05-06-2018, 03:39 PM - 1 Like	#3
ChrisPlatt Site Supporter Join Date: Nov 2007 Location: Rockaway Beach NYC Posts: 7,592	Usually this occurs because grease from the focusing helical liquefies and deposits on the diaphragm blades. Often it is not visible. I too would not recommend a DIY repair on such a pricey lens. Send it to Eric. Tomorrow I'm sending him an M35/2.8 lens for the same problem. Chris

05-06-2018, 05:59 PM	#4
gofour3 Site Supporter Join Date: Oct 2008 Location: Vancouver, Canada Posts: 7,965	Originally posted by ChrisPlatt I too would not recommend a DIY repair on such a pricey lens. Send it to Eric. Tomorrow I'm sending him an M35/2.8 lens for the same problem. +1 yep Eric fixed my K85/1.8 which had the same issue as the OP's lens. Phil.

05-07-2018, 08:02 AM	#5
Eric4 Junior Member Join Date: Jul 2015 Location: Napa, CA Posts: 33 Original Poster	Thanks for the recommendations everyone. I'll get a quote from Eric on the repair. My copy of the lens is quite clean, so it's worth having a professional deal with it.

07-11-2018, 12:55 PM	#6
leicaman New Member Join Date: Jun 2018 Posts: 1	Yes Eric is very good. I just got back from him a vintage Spotmatic F on which he did a wonderful job. In my real job I am a professional photographer with many years of experience with all sorts of repair people. I shoot film on days off for pleasure and nostalgic effect.

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