[severalsnakes]

I have searched the forum for similar issues with this lens and others and I've read through the threads that jumped out at me as being relevant. I apologize if this is 100% redundant.

Early in August I bought a used Rokinon 85/1.4 from a forum member, since I was kicking myself for missing the $199 deal that Adorama had going for a minute a few months ago. The lens appears pristine, optics are great, contacts all seem to work, smooth focus from minimum to infinity.

But the aperture lever gets very unfortunately stuck wide open. This makes the lens unreliable, obviously. I was shocked and confused by some over-exposed images I was getting, until I sat down and examined my K-30 and the lens. I've eliminated all the other variables and the lever is definitely the issue. This is a problem; I'm not ALWAYS going to want to be shooting at f/1.4, and the lever will stick wide open even "stopping down" between f/1.4 and f/2.0. If it were only sticky stopping down from apertures above f/5.6 or something bizarre like that, it might be workable, but as it is it kind of stinks.

I really don't want to spend the money to send the lens someplace to be repaired. Is there a repair I can do myself? I've not yet opened up the lens to have a look, but I'm not afraid to peep around in there.

Is there a way to completely disengage the lever and only use the lens with a manual aperture, sacrificing the stop-down metering? Would this be completely silly? I rarely use anything other than M-mode with my other lenses, so losing AV/TV/TAV/P modes is not going to keep me up at night, but I do appreciate the brightness of the viewfinder at f/1.4 while the lens will stop down the aperture for me with each shot taken. Again, I don't even know if that is a physical possibility for the lens.

I appreciate any input. I don't really want to hear "Send it back", as that is not helpful to my situation. Thanks.

Can you use it as a manual aperture lens? If you turn the aperture ring, do the blades follow? If so, you can use it as an M lens, just have to change a camera setting.

Metering is easy if you just use the Sunny 16 rule as an anchor and the histogram for feedback. While I carry a little Digisix meter to measure incident light, I use it less and less as I can make pretty accurate estimates,

[esrandall]

Sounds like you're in a tough spot. You probably saw my thread in your searches, and the first one I returned was primarily from an aperture lever that got stuck wide-open. You obviously don't have that option (unless the PF person would be willing to help out (I assume the listing had it in great condition, and there was nothing shady going on). Here's a quick tutorial from another forum, Seems feasible.

Re: Removing the aperture lever on K & M Pentax lenses: Pentax SLR Talk Forum: Digital Photography Review

Hope it works out for you. I ended sending back the second copy for other reasons, and used that money for an MX-1. In your case, being primarily a manual shooter, if the copy is good optically, then you will have a lot of fun with the lens. I know that I've removed a couple of rear flanges, and then took a dremel to them, but this is a lot different, as you don't want to risk getting any shavings into the lens body.

[severalsnakes]

Can you use it as a manual aperture lens? If you turn the aperture ring, do the blades follow? If so, you can use it as an M lens, just have to change a camera setting.

Metering is easy if you just use the Sunny 16 rule as an anchor and the histogram for feedback. While I carry a little Digisix meter to measure incident light, I use it less and less as I can make pretty accurate estimates,

Can you use it as a manual aperture lens? If you turn the aperture ring, do the blades follow? If so, you can use it as an M lens, just have to change a camera setting.

Metering is easy if you just use the Sunny 16 rule as an anchor and the histogram for feedback. While I carry a little Digisix meter to measure incident light, I use it less and less as I can make pretty accurate estimates,

Brooke, I am very comfortable using manual lenses. I have very few lenses with A settings and I have experience and accuracy estimating aperture/shutter/ISO without any input from the camera. (I take lots of photos!) Using the lens without the A-setting engaged isn't the issue. As these lenses work, the lever is held wide open until the shot is taken. At the moment the shot is taken, the camera stops down the lens to the selected aperture, then snaps back to "wide open" for easy viewing through the finder (nice and bright). When this lens "snaps back", sometimes it snaps stuck. :-(

The aperture ring works flawlessly and never gets caught up anywhere in the aperture, even wide open. It's only the lever that gets stuck at f/1.4.

I can't send the lens back, so I'm considering doing away with the lever and only operating the lens with the ring.

Sounds like you're in a tough spot. You probably saw my thread in your searches, and the first one I returned was primarily from an aperture lever that got stuck wide-open. You obviously don't have that option (unless the PF person would be willing to help out (I assume the listing had it in great condition, and there was nothing shady going on). Here's a quick tutorial from another forum, Seems feasible.

Re: Removing the aperture lever on K & M Pentax lenses: Pentax SLR Talk Forum: Digital Photography Review

Hope it works out for you. I ended sending back the second copy for other reasons, and used that money for an MX-1. In your case, being primarily a manual shooter, if the copy is good optically, then you will have a lot of fun with the lens. I know that I've removed a couple of rear flanges, and then took a dremel to them, but this is a lot different, as you don't want to risk getting any shavings into the lens body.

Thanks for the link; that's exactly what I'm considering. Glad I'm not the only one whose ever done it! I will look into this a little more...

Is there anyway to "disengage" the aperture control in the camera, I wonder? To move the little thingamajigger inside the mount up and out of the way so it's not fiddling with the aperture lever/actuator on the lens? That way I can freely adjust the aperture via the ring without the camera stopping it down and snapping it open for each shot... Obviously not, or other peeps would not be removing their aperture levers at all...

Brooke, I am very comfortable using manual lenses. I have very few lenses with A settings and I have experience and accuracy estimating aperture/shutter/ISO without any input from the camera. (I take lots of photos!) Using the lens without the A-setting engaged isn't the issue. As these lenses work, the lever is held wide open until the shot is taken. At the moment the shot is taken, the camera stops down the lens to the selected aperture, then snaps back to "wide open" for easy viewing through the finder (nice and bright). When this lens "snaps back", sometimes it snaps stuck. :-(

The aperture ring works flawlessly and never gets caught up anywhere in the aperture, even wide open. It's only the lever that gets stuck at f/1.4.

I can't send the lens back, so I'm considering doing away with the lever and only operating the lens with the ring. ..

Mea culpa and thanks, I learned something. Had no idea an A lens aperture lever wasn't decoupled when the aperture was selected manually, thought they worked liked M lenses then.

I have a Dremel tool kit you can borrow.

[severalsnakes]

Mea culpa and thanks, I learned something. Had no idea an A lens aperture lever wasn't decoupled when the aperture was selected manually, thought they worked liked M lenses then.

I have a Dremel tool kit you can borrow.

Ha! I may!

And Brooke, you've got me thinking... Maybe I don't understand the way the camera interacts with the aperture lever. Can anyone confirm what I stated above?

The camera thingamajigger "holds" the aperture open for viewing through the finder via the lever on the lens and only releases it (to snap to the effective aperture selected via the ring) at the moment the shutter is fired, then snaps back to wide open for viewing?

All of my lenses are K-mount and all of them have the little aperture lever and, as far as I know, ALL of the lenses, manual aperture ring or A-setting, work this way.

Brooke, could you tell me how your M lenses' aperture lever is decoupled? I assume you're using a DSLR (and not a film body)? And I assume you're using K-mount lenses (no adapter)? How is your camera not engaging the lever?

I think I may be confoozed. (But searching for hope!)

I did just run around the house using the Rokinon with no A-setting engaged and no green-button adjustment/metering and it fired off a dozen or so shots without sticking... I guess I'll just sit on it for now.

Thanks for all thoughts! I'll take all you're willing to give!

[Not a Number]

You are correct, all the auto K-mount lenses should work in the way you described.

Is it the auto stop-down lever itself sticking or is it the iris?

A sticking lever could be a lubrication problem, the lever is bent, or the return spring weakened, incorrectly seated or damaged. Unless the needs adjustment or replacement the problem can sometimes be fixed without any or much dis-assembly.

Sticky aperture blades would probably be from oil creeping on the the blades. This would require tearing down the lens to clean the aperture blades.

[severalsnakes]

You are correct, all the auto K-mount lenses should work in the way you described.

Is it the auto stop-down lever itself sticking or is it the iris?

A sticking lever could be a lubrication problem, the lever is bent, or the return spring weakened, incorrectly seated or damaged. Unless the needs adjustment or replacement the problem can sometimes be fixed without any or much dis-assembly.

Sticky aperture blades would probably be from oil creeping on the the blades. This would require tearing down the lens to clean the aperture blades.

Thanks for your confirmation and reply.

The problem is definitely the lever. When I realized the over exposure problem was the lens, I fiddled with recreating the issue. I have had lenses in the past with slow blades and oily blades. The blades on this Rokinon are clean and snappy without flaw when I rotate the aperture ring rapidly. They never slow down, drag or catch. BUT, when I flick the lever at ANY aperture (even f/2, ONE stop on the ring), the lever will catch in the "wide open" position after a number of flicks. I might flick it twice before it sticks, or might have to flick it 20 times. I have to give it a nudge for it to release; jostling the lens, pulling gently on the lever outward, adjusting the focus or turning the lens upside down and sideways do nothing to release the lever. (I've kind of been worrying over it this evening, if you can't tell.)

Either way, I don't want to go out with my camera, wait until I get an overexposed image, and stop what I'm doing to take off the lens and give the lever a push...

I think you understand better than me. My education continues.

My Pentax M lenses aren't decoupled and I didn't know that but I have a lame excuse - an aberration in the time-space continuum between my ears.

Folks in our local camera club know I shoot Pentax so I've gotten donations of old Pentax and Ricoh gear from retirees cleaning out closets. Haven't done much except test drive a few M lenses in my office. The stuff keeps staring at me from the shelf and I think about lens reversals and stacking but I've luckily, been busy. My workhorse lenses are all modern.

So I put an Pentax M 50 1.7 on a K5 body and it works. I never thought about stop down metering because I don't use the camera meters. Nor did I see the aperture lever when I looked at the mount, but its there.

My first camera was a Yashica TL Electro X, bought new in 1973. It had a 50mm lens with an M42 mount. I got very used to changing the shutter and aperture until the meter said I was okay. All manual so it got dark when you adjusted the aperture. Pretty soon I was in the closet loading rolls of Ektachrome into a Patterson Multi Tank and processing slides in the bathtub. Life got in the way and I got away from photography until the mid 90's. Bought a used Yashica TL Electro X which I didn't use much until I sold it to KEH about 5 years ago.

To double check and get it in my head, I put the M 50 and an M 28 on a K5 and a Pentax ME today. They both hold the aperture open for metering. You can see the stopped down aperture on the K5 with the DoF preview which I assume, decouples the lever. The only way to stop that is to remove the lever assembly, cut off the lever or add an adapter that loses the mechanical coupling, like a M42 to K Mount adapter or a manual extension tube.

I'll be having a slice of humble pie when this is finished.





.

[esrandall]

Seems to me that you would obviously just need to snip the lever down to the flange level for it not to catch. I bet you could remove the flange (to create some working room), and then just use a pair of sharp snips to cut it down. I would hold the lens with the rear facing down, just to play it safe (no errant shaving getting inside). The lever on mine was pretty thin, and I bet snips would get it easy. Then just run your fingers along the cut to smooth it over, reinstall the flange - good to go.

I think it's worth a shot. If my two copies hadn't had other issues to go along with the stuck lever - I would've felt confident trying this. I already use a pair of manual lenses with dremeled flanges, and when I removed them, there was plenty of lever to see. The extension tube idea is a great one too, even though you would need to figure out the parameters of your new magnification spec

Good luck!

[Not a Number]

You might be able to see what is going on by removing the rear bayonet. Avoid removing the aperture ring if possible as there are most likely tiny ball bearings and a spring or two that easily fly off into oblivion. JIS drivers are highly recommended.

[severalsnakes]

Seems to me that you would obviously just need to snip the lever down to the flange level for it not to catch. I bet you could remove the flange (to create some working room), and then just use a pair of sharp snips to cut it down. I would hold the lens with the rear facing down, just to play it safe (no errant shaving getting inside). The lever on mine was pretty thin, and I bet snips would get it easy. Then just run your fingers along the cut to smooth it over, reinstall the flange - good to go.

I think it's worth a shot. If my two copies hadn't had other issues to go along with the stuck lever - I would've felt confident trying this. I already use a pair of manual lenses with dremeled flanges, and when I removed them, there was plenty of lever to see. The extension tube idea is a great one too, even though you would need to figure out the parameters of your new magnification spec

Good luck!

Thank you! I have removed an overly-large flange before. I just snipped it off kind of like you described. I put pieces of Scotch tape over the openings in the mount (and the rear element, obviously), to prevent bits from falling in and it seemed to work well.

I am going to FIRST try using the lens without engaging the A-setting or the green button and see if a simple and gentle aperture-ring only style of use will suit the lens' fickle nature. If that doesn't work, I'm going to take off the mount like Not a Number suggested and see if I can readily identify what is causing the problem. If all else fails, I will snip off the damn lever and call it done. No use having the lens at all if it's just going to have a stuck aperture.

Thanks everyone, for your help, and for clarifying exactly what was going on here. :-)

[kiwi_jono]

Good luck!
I have been lucky with my Bower branded 85mm one and no problems but I have heard of similar issues.

Its a pretty good lens optically, so I think you will enjoy it. It can take a bit of effort getting close focus at f1.4 right though.

[Not a Number]

Well it is your lens and you are free to do with it as you wish. If it is an "A" type lens IMHO it is a crime to mutilate a lens so as to cripple its functionality when it is something that is probably easily repaired or adjusted. Especially a lens in a much desired focal length and speed.

Is the lens still under warranty?

[severalsnakes]

Well it is your lens and you are free to do with it as you wish. If it is an "A" type lens IMHO it is a crime to mutilate a lens so as to cripple its functionality when it is something that is probably easily repaired or adjusted. Especially a lens in a much desired focal length and speed.

Is the lens still under warranty?

I know, that's why it tears me up. I don't want to mutilate it, but I also want to be able to use it. I'm taking baby steps, don't worry!

I bought the lens second-hand from a forum member here, and he did include the warranty card. The Marketplace ad indicates the lens was less than a year old when I bought it last month, and it did include what appears to be the original warranty card. However, I admit I did already try to take the screws out of the mount to look inside the lens. I didn't get that far because two of the screws are tight and I didn't have my nice screwdriver to get them out, so I stopped and just put the other two screws back in. I'm sure that any monkey looking at the screws on the mount will see evidence that they've been fiddled with, which may render the warranty invalid, anyway. I've never had to enact a warranty and I'm not sure I'd want to jump through all the necessary hoops. If it gets to the point where I'm considering the warranty option, I'll probably just take it to a repair shop. I'm willing to pay for convenience.

We're chilling for now. I got through all of yesterday without throwing it against a wall, so that's a good sign.

---------- Post added 09-02-14 at 07:29 AM ----------

Good luck!
I have been lucky with my Bower branded 85mm one and no problems but I have heard of similar issues.

Its a pretty good lens optically, so I think you will enjoy it. It can take a bit of effort getting close focus at f1.4 right though.

It IS really nice, optically, and I have already made some good shots with it over the weekend when I was on vacation with the in-laws... It was the first time I'd really used the lens since I bought it, besides some test shots, so I was able to be both REALLY pleased with the nice images, and SUPER DISAPPOINTED when I discovered the lens was flawed.

But, live and learn. I bought a lens once where the focus ring didn't turn to infinity. I returned it and now I check all lenses for that ability. I bought another lens with slow, scummy aperture blades. Now also something I check for. NOW I've had a lens with a faulty aperture lever... chalk it up to experience.

It's still a nice lens.