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12-03-2015, 07:11 PM   #1
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Rokinon 85mm f1.4 - Wrong aperture?

I hope this is the right subforum..

I got my Rokinon 85mm a few months ago and this is the third time I've used it, I went on vacation and used it extensively. But this time it did something it hadn't done before, the maximum aperture I could select in A mode was [still is] f/2.8. The minimum aperture is f/45 I think, maybe 75. Of course this is nuts, so something is wrong. I worked around that in my trip by shooting wide open by either being on f2.8, or going off A mode. The bad thing of using the aperture ring is that the blades don't follow, so it's always wide open. Actually, it doesn't stop down even if I shoot, the only way it will stop down is in A mode, and I don't know what stop I'm getting to because the numbers are off!

:long_sigh:

Of course this is a bit frustrating, and there wasn't much I could do while travelling. Now I've read a little and cleaned the terminals but everything is still the same. No other lens that I have exhibits this behaviour, except my other Rokinon, the 8mm 3.5. It shows the correct aperture, but only stops down in A mode. Manual aperture ring is useless [or simply wide open all the time].

I'm using my beloved K-01 PandaTrooper, any ideas?


PS. I can't wait to finish developing my photos.. they are around 1,000 and it was such an awesome place and every step I took was a photo waiting to be taken.. once I'm done I'll post some!!

12-03-2015, 08:12 PM - 1 Like   #2
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This his means your number 4 contact is insulated when it should be conducted by the 85.
the 8mm wouldn't be effected because number 4 is a insulated contact on that lens.
#4 conductor is 2nd from locking pin
Did you clean the lens mounting plate?

Last edited by Sliver-Surfer; 12-03-2015 at 08:20 PM.
12-03-2015, 08:13 PM   #3
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That's bizarre. I use the same 85 with a K-01 (or K-3) in club shooting and it is magnificent with no troubles. On the K-01, use a decent screen loupe (my strong preference is the Perfect GGS because it is optically superb). Nail focus easily in very low light - every time. Really, for that particular situation it is superior to the K-3.

I'd be curious to know if the lens is stopping down to f/2.8 when you go into auto. I suspect that the lens sits at f/2.8 when you mount it (which is actually normal - as a sensor preservation protocol). Are you getting correct exposures in A setting?

Do some troubleshooting. Make sure no other A or AF lenses are giving you similar false readings - focus on anything that is faster than f/2.8 if you have it. If not, my best guess is something electronic in the lens, or if you're really lucky - just a contact problem solved by cleaning off the contacts (unlikely).

Keep us posted. This is a new one, I think.
12-03-2015, 08:37 PM - 1 Like   #4
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I see you have a 40mm xs if you put that on your camera and it reads f5.6-f45 then its your camera..if it reads normal your 85mm has a dirty area near the #4 conductor pin or the lens mount is warped

12-03-2015, 08:51 PM   #5
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Maybe your lens are loose the spring on back of lens. Check it.
12-03-2015, 11:05 PM   #6
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QuoteOriginally posted by Sliver-Surfer Quote
This his means your number 4 contact is insulated when it should be conducted by the 85.
the 8mm wouldn't be effected because number 4 is a insulated contact on that lens.
#4 conductor is 2nd from locking pin
Did you clean the lens mounting plate?
There is one insulated contact, but it's either #5 or #3, depending where you start counting.. I don't know which is the locking pin.
There's a group of four, then one, then two.. would a picture be better?


QuoteOriginally posted by ScooterMaxi Jim Quote
That's bizarre. I use the same 85 with a K-01 (or K-3) in club shooting and it is magnificent with no troubles. On the K-01, use a decent screen loupe (my strong preference is the Perfect GGS because it is optically superb). Nail focus easily in very low light - every time. Really, for that particular situation it is superior to the K-3.

I'd be curious to know if the lens is stopping down to f/2.8 when you go into auto. I suspect that the lens sits at f/2.8 when you mount it (which is actually normal - as a sensor preservation protocol). Are you getting correct exposures in A setting?

Do some troubleshooting. Make sure no other A or AF lenses are giving you similar false readings - focus on anything that is faster than f/2.8 if you have it. If not, my best guess is something electronic in the lens, or if you're really lucky - just a contact problem solved by cleaning off the contacts (unlikely).

Keep us posted. This is a new one, I think.
Oh yeah, manual focus is a bit hard but I got the hang of it, even wide open. Peaking helps a lot!

When I get into A mode it stays at f/1.4, yet it says f/2.8. EXIF data says 2.8 as well.
I'm getting.. good exposures, just inaccurate. For instance I simply shot wide open all night in Av mode. All was cool. But in daylight I couldn't be bothered with that nonsense and switched to my 35mm f/2.4 and the fisheye.

The 2.4 gets to 2.4, I guess I can try my Vivitar 50mm 1.7, but it's a completely manual lens.
I'll try cleaning the contacts again =[ I seriously doubt there's dirt, I take too much care but let's hope so..



QuoteOriginally posted by Sliver-Surfer Quote
I see you have a 40mm xs if you put that on your camera and it reads f5.6-f45 then its your camera..if it reads normal your 85mm has a dirty area near the #4 conductor pin or the lens mount is warped
Yup, the 40 XS and 35mm 2.4 work flawlessly.
It's definitely the lens.. warping sounds unlikely but I'll check for that too.



QuoteOriginally posted by KDD Quote
Maybe your lens are loose the spring on back of lens. Check it.
I'll check for the spring too, thanks!

---------- Post added 12-04-15 at 01:05 AM ----------

Update: I cleaned them and it went past the 2.8, all the way to f/1.4. I don't believe it..
I still can't make the aperture ring work manually, though.
12-04-2015, 12:25 PM   #7
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QuoteOriginally posted by FoTom Quote
Update: I cleaned them and it went past the 2.8, all the way to f/1.4. I don't believe it..
Glad to hear it.
12-04-2015, 05:59 PM   #8
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QuoteOriginally posted by Sliver-Surfer Quote
Glad to hear it.
Many thanks for all, I panicked and the simplest solution was the correct one [although it didn't work the first time haha].

12-04-2015, 11:14 PM   #9
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I couldn't get my Samyang 85 to work properly the first time i took it out but used the green button on my K3 and got some fairly good shots anyway. Changed the OFV lighting from 10 to 30 seconds and took it out again today. The day was overcast, but everything worked properly as far as I can tell. All the shots in my Dec 2015 gallery are with the Samyang 85 thus far -- but won't promise I won't add some shots with different lenses as time goes on. https://lawrencehelm.smugmug.com/RiverPhotography/Dec-2015/

Lawrence
12-21-2015, 10:31 PM   #10
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QuoteOriginally posted by Historicity Quote
I couldn't get my Samyang 85 to work properly the first time i took it out but used the green button on my K3 and got some fairly good shots anyway. Changed the OFV lighting from 10 to 30 seconds and took it out again today. The day was overcast, but everything worked properly as far as I can tell. All the shots in my Dec 2015 gallery are with the Samyang 85 thus far -- but won't promise I won't add some shots with different lenses as time goes on. https://lawrencehelm.smugmug.com/RiverPhotography/Dec-2015/

Lawrence
What interesting photos! Seems like the dogs were having fun too =]
I had my green button set to something other than P-line, so that didn't work for me either, but how cool it did work out for you.
The 85mm is a beast, love the lens, but damn it's hard to focus at f/1.4 haha. Lucky me, my only Pentax camera is my K-01, and manual focusing is a breeze [against an OVF] with peaking.

I still haven't developed all my RAWs, I took 1,038 and when I finish they will be ~800.. When I finish I'll share if anyone's interested!
12-22-2015, 09:15 AM   #11
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Using the K5iis with the Samyang lenses

QuoteOriginally posted by FoTom Quote
What interesting photos! Seems like the dogs were having fun too =]
I had my green button set to something other than P-line, so that didn't work for me either, but how cool it did work out for you.
The 85mm is a beast, love the lens, but damn it's hard to focus at f/1.4 haha. Lucky me, my only Pentax camera is my K-01, and manual focusing is a breeze [against an OVF] with peaking.

I still haven't developed all my RAWs, I took 1,038 and when I finish they will be ~800.. When I finish I'll share if anyone's interested!
FoTom,

Thanks. I decided to set my K5iis up as a manual-lens-only camera and leave my K3 for autofocus lenses; rather than switching back and forth and confusing myself. Since I am very happy with my Samyang 85mm I decided to concentrate on my Samyang 35mm. Thus far it is excellent when I step it down a bit. Last time out I tried it at f: 3.5 and a lot of shots were blurry -- Actually that doesn't hurt me since I don't as a rule shoot that close to wide open on a hike. So at 6.0 or 7.1 I get excellent image quality across the picture. I had the 85mm in the bag in case I wanted to switch lenses the last time out, but never did. I must say the only downside to the Samyang lenses I've encountered thus far is their sizes -- the 35mm is larger than the 85mm btw. With Pentax I can have a 15mm, 21mm and 70mm in my bag and switch them back and forth pretty easily, but my two Samyang lenses more than fill up my bag and the last time I switched them on a hike I lost the back lens cap in the sand some place. Fortunately I bought some aftermarket spares in the past and had them on hand.

When I began using the K5iis for the Samyangs I had a bit of a problem seeing info in the viewfinder and so added a little Ricoh OVF magnifier and that helps. I would hate to think I needed another K3 just to shoot manual lenses -- by that I mean that if using the K3 for the manual lenses was much easier than using the K5iis I would be tempted to switch functions between the K3 & K5iis or perhaps buy a K3ii and use it for the AF lenses and the K3 for the manual, but I trust that I'm just in a learning curve and won't have to go that far to get things right.

Lawrence
12-23-2015, 03:18 AM   #12
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QuoteOriginally posted by Historicity Quote
FoTom,

Thanks. I decided to set my K5iis up as a manual-lens-only camera and leave my K3 for autofocus lenses; rather than switching back and forth and confusing myself. Since I am very happy with my Samyang 85mm I decided to concentrate on my Samyang 35mm. Thus far it is excellent when I step it down a bit. Last time out I tried it at f: 3.5 and a lot of shots were blurry -- Actually that doesn't hurt me since I don't as a rule shoot that close to wide open on a hike. So at 6.0 or 7.1 I get excellent image quality across the picture. I had the 85mm in the bag in case I wanted to switch lenses the last time out, but never did. I must say the only downside to the Samyang lenses I've encountered thus far is their sizes -- the 35mm is larger than the 85mm btw. With Pentax I can have a 15mm, 21mm and 70mm in my bag and switch them back and forth pretty easily, but my two Samyang lenses more than fill up my bag and the last time I switched them on a hike I lost the back lens cap in the sand some place. Fortunately I bought some aftermarket spares in the past and had them on hand.

When I began using the K5iis for the Samyangs I had a bit of a problem seeing info in the viewfinder and so added a little Ricoh OVF magnifier and that helps. I would hate to think I needed another K3 just to shoot manual lenses -- by that I mean that if using the K3 for the manual lenses was much easier than using the K5iis I would be tempted to switch functions between the K3 & K5iis or perhaps buy a K3ii and use it for the AF lenses and the K3 for the manual, but I trust that I'm just in a learning curve and won't have to go that far to get things right.

Lawrence
I see, nice setup. I'm saving for some glass too, and a second body -either a K-S2 in the meanwhile, and later on a K-3 II, or directly the K-3 II. Not sure.
Regarding lenses, yup, the Rokinons are BIG. That's why I got the Pentax 35mm f/2.4, and I am considering the 21 Limited. I'm not much of a zoom guy, but the 18-135 or 16-85mm will be in my arsenal as well. The idea of switching to Pentax [from Canon] was the WR, and so far none of my lenses or cameras are WR haha. But I already got a nice collection and am [quite almost] ready to get that second body and one WR lens.

During my trip I had a backpack with both Rokinons [the 8mm, the 85mm], and the 35mm, It went alright I think =] But like you say, switching them is quite an endeavour while hiking, walking, etc.. in a studio it wouldn't be a problem, but in action.. damn hehe.

The 8mm seemed to be the least sharp of the three, and I shot pretty much always at f/8. Maybe I still have to learn how to use it properly, it's my first fisheye.
12-24-2015, 08:12 AM   #13
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Pentax and WR lenses

FoTom: You wrote, "The idea of switching to Pentax [from Canon] was the WR, and so far none of my lenses or cameras are WR haha. But I already got a nice collection and am [quite almost] ready to get that second body and one WR lens."

I started with Olympus -- knew I'd be hiking with whatever I chose and Olympus had a reputation for ruggedness as well as weather protection. In regard to weather-protected lenses, Olympus like Pentax primarily meant zooms. What bothered me about Olympus is that the small cameras of a size for hiking weren't weather sealed. The cameras that were weather-sealed were as large as APS-C cameras. However I stuck with them until they quit making DSLRs. Over in the Pentax world there are complaints that Pentax has done the same thing. The K3 apparently is as large as the Nikon 7200. I think they are both smaller than the Olympus E3 but I may be wrong about that.

I've gotten used to the idea of using zooms in bad weather. If the weather is bad I'm not likely to get any good shots on a hike anyway so I might as well have a zoom. I used the 18-135mm and later on began using the 16-85mm. I've relegated my K5 for bad weather and the zooms.

In regard to primes I was in a discussion on another forum recently with a man from the Philippines who bemoaned the fact that Pentax didn't have more WR primes. Yes the 55mm and the 100mm are weatherproofed, but he especially wanted a walking-around 35mm WR. Someone else voiced the Pentax philosophy suggesting that the only people likely to want primes when it rained were photographers shooting weddings and Pentax had weatherproofed the 55mm and 100mm for them. The Philippine man however said that he experienced an average of 25 tornadoes a year and didn't really like shooting zooms; so he had a real problem. Someone said that overall there probably wasn't a very large market for more WR primes, but he thought the market was much larger than Ricoh suspected. Living as I do in Southern California I can't quite imagine the sort of weather he is experiencing.

When Oympus quit making DSLRs I switched to Pentax not because they had a better WR lineup but because they produced equally rugged cameras and some very fine little primes, lenses ideal for the hiker -- I saw Pentax as a sort of continuation of what I perceived as the original Olympus ideal.

If it isn't raining when I start on a hike but it is supposed to rain later on, I can start out with a Pentax LTD prime and then have the 18-135 or 16-85 zoom in my bag if it really does start to rain.

Since a lot of photographers use more than one brand, I thought I might eventually add the Olympus micro 4/3 -- probably the OMD EM1; so I check them from time to time. They probably can't quite match a quality APS-C camera and lens setup yet, but they are trying. I still have a lot of old 4/3 Olympus lenses and many of those will fit the modern micro 4/3 system. Olympus still isn't producing many weatherproofed primes, the 8mm fisheye and the 60mm macro is all as far as I know. The Pentax 55mm is closer to being a walk-around lens being 35mm equivalent to 82.5mm whereas the micro 4/3 60mm is 35mm equivalent to 120mm, but neither would really satisfy the fellow in the Philippines. The only real reason for keeping my eye on Olympus is the fear I see from some on the forums that Ricoh may eventually give up on Pentax APS-C cameras.

I'm looking out my study window at the mountains and there is a heavy cloud hanging down over most of them -- it probably won't rain, but it could be extremely damp -- enough so to leave my primes at home and take a WR zoom if I go out. Pentax is still better for what I do than any other brand.

Lawrence
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