Help with Rokinon 85/1.4!

treebeard · 10-05-2013, 09:47 AM

Just got this in the mail today and I really like the feel of it on my K-30. However, it won't work in "A" mode. I turn the camera on, input the focal length and I am unable to change the aperture via the dial like I can with my SMC-A 50/1.7. The only mode that it seems to work in is in Manual mode and I have to change the aperture via the lens and push the green button on my K-30. Does anyone have any advice because the few shots I took in Manual mode really impressed me. I checked the contacts on the lens and my camera but like I said my 50/1.7 works fine. Also, the aperture lever on the lens seems to move as it should when I change the aperture manually and when I put it in "A" mode it seems to move back and forth like the one on my 50/1.7.

aurele · 10-05-2013, 10:00 AM

Put the lens on F22, it should then work as a "A" lens (or on the "A" if there is one on the aperture ring).

treebeard · 10-05-2013, 10:17 AM

I put it on the A setting but that's a no go.perhaps I just need to clean the contacts on the lens. what should I use?

aurele · 10-05-2013, 10:30 AM

cleaning the contact is a good idea, use a solution with 80/90% alcohol in it.

treebeard · 10-05-2013, 11:43 AM

Will try that.

Na Horuk · 10-05-2013, 11:51 AM

Is it a new or used lens?
Is it really in A mode? You need to push the little button on the aperture ring to set it into A mode. Make sure this is set correctly before you try cleaning.

treebeard · 10-05-2013, 12:57 PM

I cleaned the contacts on the lens with a wipe that's 80% alcohol and everything seemed to be fine. However, now I am noticing that the lens is not really locking onto my body the way it should. If I put the lens on firmly, turn the camera on and then input the focal length it seems fine at first...but then the aperture will disappear and I get F- - - where the aperture should be. If I move the lens just slightly the aperture will flicker and then back to F - - -. It seems to be very sporadic like this. Now I am perplexed.

Last edited by treebeard; 10-05-2013 at 02:01 PM.

carrrlangas · 10-05-2013, 03:15 PM

Then the problem is with the contacts. This happened to me with the FA80-320 (common failure with that lens) You´ll need to dissasemble it and see which contact or if the plate supporting them is loose.

If you try pushing the contacts down they should return to their possition with strength (I don´t know how to say it in english, they are spring loaded). Compare with other lens you have

treebeard · 10-05-2013, 03:27 PM

Will do. I really like the lens but the "locking" issue I think is throwing focus confirmation off with my K-30. When I put the lens on and it clicks like it should the focus confirmation seems to be right on, but after walking around with the lens and changing the aperture it seems to be off.

carrrlangas · 10-05-2013, 05:05 PM

That is hardly related to the electrical contacts, but could have to do with a loose mount.
Oesides that it could be the phenomenom called "focus shift", related to comma and other azerrations. Look it up.

treebeard · 10-05-2013, 05:29 PM

I just can't seem to figure it out. Both of my other manual lenses work fine...they click snugly and
work as expected. Stepping away from it for the night. I will look it up.

bibz · 10-11-2013, 05:34 AM

Sounds like a problem with the lens imo. My Rokinon 85 and k30 work flawlessly in Av

rawr · 10-11-2013, 02:37 PM

On my K-5, I have had a similar problem with a Sigma 105, but not with my Rokinon 85.

I suspect a tiny mis-alignment of the pins body to lens could be a factor sometimes. When I mount the Sigma, and firmly turn it to lock and click, I always give it a little jiggle afterwards to settle the pins, even though any possible movement is slight.

10-05-2013, 09:47 AM	#1
treebeard Veteran Member Join Date: Nov 2008 Location: Windham, NH Photos: Gallery \| Albums Posts: 793	Help with Rokinon 85/1.4! Just got this in the mail today and I really like the feel of it on my K-30. However, it won't work in "A" mode. I turn the camera on, input the focal length and I am unable to change the aperture via the dial like I can with my SMC-A 50/1.7. The only mode that it seems to work in is in Manual mode and I have to change the aperture via the lens and push the green button on my K-30. Does anyone have any advice because the few shots I took in Manual mode really impressed me. I checked the contacts on the lens and my camera but like I said my 50/1.7 works fine. Also, the aperture lever on the lens seems to move as it should when I change the aperture manually and when I put it in "A" mode it seems to move back and forth like the one on my 50/1.7.

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10-05-2013, 10:00 AM	#2
aurele Veteran Member Join Date: Jan 2011 Location: Paris, France Photos: Albums Posts: 3,217	Put the lens on F22, it should then work as a "A" lens (or on the "A" if there is one on the aperture ring).

10-05-2013, 10:17 AM	#3
treebeard Veteran Member Join Date: Nov 2008 Location: Windham, NH Photos: Gallery \| Albums Posts: 793 Original Poster	I put it on the A setting but that's a no go.perhaps I just need to clean the contacts on the lens. what should I use?

10-05-2013, 10:30 AM	#4
aurele Veteran Member Join Date: Jan 2011 Location: Paris, France Photos: Albums Posts: 3,217	cleaning the contact is a good idea, use a solution with 80/90% alcohol in it.

10-05-2013, 11:43 AM	#5
treebeard Veteran Member Join Date: Nov 2008 Location: Windham, NH Photos: Gallery \| Albums Posts: 793 Original Poster	Will try that.

10-05-2013, 11:51 AM	#6
Na Horuk Veteran Member Join Date: Feb 2012 Location: Slovenia, probably Photos: Gallery \| Albums Posts: 11,186	Is it a new or used lens? Is it really in A mode? You need to push the little button on the aperture ring to set it into A mode. Make sure this is set correctly before you try cleaning.

10-05-2013, 12:57 PM	#7
treebeard Veteran Member Join Date: Nov 2008 Location: Windham, NH Photos: Gallery \| Albums Posts: 793 Original Poster	I cleaned the contacts on the lens with a wipe that's 80% alcohol and everything seemed to be fine. However, now I am noticing that the lens is not really locking onto my body the way it should. If I put the lens on firmly, turn the camera on and then input the focal length it seems fine at first...but then the aperture will disappear and I get F- - - where the aperture should be. If I move the lens just slightly the aperture will flicker and then back to F - - -. It seems to be very sporadic like this. Now I am perplexed. Last edited by treebeard; 10-05-2013 at 02:01 PM.

10-05-2013, 03:15 PM	#8
carrrlangas Veteran Member Join Date: Mar 2012 Location: Joensuu (Finland) Photos: Gallery Posts: 1,761	Then the problem is with the contacts. This happened to me with the FA80-320 (common failure with that lens) You´ll need to dissasemble it and see which contact or if the plate supporting them is loose. If you try pushing the contacts down they should return to their possition with strength (I don´t know how to say it in english, they are spring loaded). Compare with other lens you have

10-05-2013, 03:27 PM	#9
treebeard Veteran Member Join Date: Nov 2008 Location: Windham, NH Photos: Gallery \| Albums Posts: 793 Original Poster	Will do. I really like the lens but the "locking" issue I think is throwing focus confirmation off with my K-30. When I put the lens on and it clicks like it should the focus confirmation seems to be right on, but after walking around with the lens and changing the aperture it seems to be off.

10-05-2013, 05:05 PM	#10
carrrlangas Veteran Member Join Date: Mar 2012 Location: Joensuu (Finland) Photos: Gallery Posts: 1,761	That is hardly related to the electrical contacts, but could have to do with a loose mount. Oesides that it could be the phenomenom called "focus shift", related to comma and other azerrations. Look it up.

10-05-2013, 05:29 PM	#11
treebeard Veteran Member Join Date: Nov 2008 Location: Windham, NH Photos: Gallery \| Albums Posts: 793 Original Poster	I just can't seem to figure it out. Both of my other manual lenses work fine...they click snugly and work as expected. Stepping away from it for the night. I will look it up.

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10-11-2013, 05:34 AM	#12
bibz Senior Member Join Date: Nov 2009 Location: Newcastle, AU! Posts: 276	Sounds like a problem with the lens imo. My Rokinon 85 and k30 work flawlessly in Av

10-11-2013, 02:37 PM	#13
rawr Veteran Member Join Date: Jun 2009 Posts: 11,913	On my K-5, I have had a similar problem with a Sigma 105, but not with my Rokinon 85. I suspect a tiny mis-alignment of the pins body to lens could be a factor sometimes. When I mount the Sigma, and firmly turn it to lock and click, I always give it a little jiggle afterwards to settle the pins, even though any possible movement is slight.