[zburatoru]

Third shot is what you should be getting. It seems you didn't focus right in other shots. As everyone told you already, it's not easy to get perfect focus at f1.4.

What about the glow? Just zoom in and look at that grass! Is it normal?

[BigMackCam]

I agree that the third of your test shots is closest to a normal result. That said, the out-of-focus rendering generally, especially the highlights, really does look completely wrong to me. It doesn't reflect my own experience with this lens at all.

I'm beginning to wonder if the lens has either been assembled incorrectly... either at the factory, or by someone else subsequently. I know you said you bought the lens new, but was it from a reliable source - i.e. an official dealer? I'd be tempted to go back to them, or even to contact Samyang in your region, and show them your photos. I believe your lens is covered by a one year warranty in Romania, but even if the warranty has recently expired, it's worth seeing if they might inspect and repair the lens - either without charge, or for a nominal charge...

[5r82]

Did you try to completely magnify image in live view while focus peaking? K-500 has focus peaking, right? These shots looks like mis-focused at f1.4 on APS-C sensor. Get the same when I miss focus on K-5II while on K-1 it's a different story. You should be getting close to 3rd photo with little practice and patience. Don't give up quickly.

[clackers]

Thank you all for the answers! What do you think about the alternatives? I really like the images from Mitakon creator 85mm f2: bokeh like leica, very good contrast and colors... There could be Pentax m 85mm f2 or K 85mm f1.8. 77mm limited will be the best choice but very, very expensive. I really love the bokeh from Samyang but in direct light f1.4 and 1.6 it's almost unusable... So, what's the point if you can use it only at 1.8 and above? Not to say that it's got sticky level aperture problem sometimes...

I will talk about all very fast lenses here rather than just the Samyang - we really have to up our technique and practice, Zburatoru.

It is easier to shoot a camera at f11 than f1.4.

The depth of field is small, especially when close to the subject, the resolution of the image is inferior to say f5.6 or f5.8, and with a manual lens it is very easy to miss focus. Even with autofocus, if the camera picks out the nose instead of the eye, you will have to throw those photographs away, they're unusably soft for a portrait.

The bokeh will be nice and smooth, like in my shot with that Samyang of yours here … but the central subject can suffer. The focus is on the two black rectangles.




A pro would typically take this with their 24-70 or 70-200 at f2.8.

[zburatoru]

Did you try to completely magnify image in live view while focus peaking? K-500 has focus peaking, right? These shots looks like mis-focused at f1.4 on APS-C sensor. Get the same when I miss focus on K-5II while on K-1 it's a different story. You should be getting close to 3rd photo with little practice and patience. Don't give up quickly.

But really, focusing with this lens it's a pain in the ass!

---------- Post added 02-19-2019 at 10:03 PM ----------

I agree that the third of your test shots is closest to a normal result. That said, the out-of-focus rendering generally, especially the highlights, really does look completely wrong to me. It doesn't reflect my own experience with this lens at all.

I'm beginning to wonder if the lens has either been assembled incorrectly... either at the factory, or by someone else subsequently. I know you said you bought the lens new, but was it from a reliable source - i.e. an official dealer? I'd be tempted to go back to them, or even to contact Samyang in your region, and show them your photos. I believe your lens is covered by a one year warranty in Romania, but even if the warranty has recently expired, it's worth seeing if they might inspect and repair the lens - either without charge, or for a nominal charge...

I believe too that it's a calibration problem creating more reflections from the metal parts... Plus the pronounced field curvature: you won't focus at 1.4 as you focus at 5.6...

[clackers]

. Plus the pronounced field curvature: you won't focus at 1.4 as you focus at 5.6...

I'm not aware that the Samyang 85mm has much field curvature at all.

[brightseal]

But really, focusing with this lens it's a pain in the ass!

Like how do you focus with it? Seriously. I shot one roll of film with it at a party in a basement one night 3 years ago with an MZ-S or Pz1p I can't remember, photos came out sharp but if not for the prism focus I'm lost.

[5r82]

In order to see what the depth of field at f1.4 on 85mm looks like please see below photos that I took on K-5II while using OVF indicator only. K-5II doesn't have a focus peaking, one very usable thing for manually focusing fast lenses. It's live view is mostly useless for this as resolution of it's LCD screen is not big enough. It's different story with K-1 which has very usable live view. Please click on the photos so that you can see them in full resolution. The second photo is screen capture at 100% magnification in my Photoshop window. As you can see, DOF is very shallow and you will need patience and practice. Expect this with any other lens that you will get. Basically you need to learn how to use it to it's full potential, understand it's bad and good side, etc. Good luck.

[zburatoru]

In order to see what the depth of field at f1.4 on 85mm looks like please see below photos that I took on K-5II while using OVF indicator only. K-5II doesn't have a focus peaking, one very usable thing for manually focusing fast lenses. It's live view is mostly useless for this as resolution of it's LCD screen is not big enough. It's different story with K-1 which has very usable live view. Please click on the photos so that you can see them in full resolution. The second photo is screen capture at 100% magnification in my Photoshop window. As you can see, DOF is very shallow and you will need patience and practice. Expect this with any other lens that you will get. Basically you need to learn how to use it to it's full potential, understand it's bad and good side, etc. Good luck.

Yes, I understand it. I have a lot of experience with manual focusing but to shoot 5 frames to get a decent sharpness it's a little too much! And one it's glowy and bad CA in the center, one it's not so glowy, one it's contrasty, little Ca but not sharp, etc... I will try to send it back. I'm giving it another chance... Let's see what's coming back...

[Gimbal]

Right or wrong, my copy has the same glow wide open in certain situations.

[zburatoru]

Right or wrong, my copy has the same glow wide open in certain situations.

How it's focusing? The image has strong green CA in the center at first focus beep and if you continuing to focus it's disappears?

[BigMackCam]

I have a lot of experience with manual focusing but to shoot 5 frames to get a decent sharpness it's a little too much!

Do you have experience with manual focusing a very fast telephoto lens? E.g. 85mm or longer with an f/1.4 or wider aperture? If not, this is why you are having difficulty focusing this lens accurately. Especially with very close up subjects, the depth of field is tiny.

How it's focusing? The image has strong green CA in the center at first focus beep and if you continuing to focus it's disappears?

As I suggested earlier in the thread, focus confirmation on DSLR cameras isn't 100% accurate. It will beep and you'll see the focus confirmation indicator when you get close to being in focus, but not at the precise point where it is exactly in focus... and it will remain active across a small focusing range either side of the correct focus setting. Given the tiny depth of field we're talking about here, you simply can't rely on focus confirmation for accurate focusing.

Only areas of the subject that are in *perfect* focus will be free of glow and/or blur. Anything in front of or behind the exact focus distance, especially at fast apertures, will have some glow and/or blur. And if you move back or forth even the slightest amount while taking your shot, the point of accurate focus can change enough to throw the subject you thought you were focused on out of focus.

If you then add an extension ring for close focusing (as I believe you mentioned in an earlier post), the depth of field will become even narrower, and focusing even more critical. The glow, aberrations etc. will be even more noticeable.

Everything I've mentioned above is the same for *any* fast, telephoto, manual focusing lens, used on any DSLR camera that offers focus confirmation.

[Gimbal]

How it's focusing? The image has strong green CA in the center at first focus beep and if you continuing to focus it's disappears?

I always use live view to focus when the depth is razor thin, it just doesn’t work with AF.
With AF confirmation the result depends on if you turn the focus ring from close to far, or from far to close. You just don’t know where the focus end up. So it's not an action lens.

[pres589]

I think it's better to look at the distance scale on the focus ring and estimate the distance, then raise the camera to your eye and shoot using your own visual abilities, than to use focus confirmation from the AF system.

If I wanted to use fast manual glass on my Pentax digital camera, I would swap the focusing screen for one with a split prism, and maybe add a magnifying eye piece as well.

[zburatoru]

Do you have experience with manual focusing a very fast telephoto lens? E.g. 85mm or longer with an f/1.4 or wider aperture? If not, this is why you are having difficulty focusing this lens accurately. Especially with very close up subjects, the depth of field is tiny.



As I suggested earlier in the thread, focus confirmation on DSLR cameras isn't 100% accurate. It will beep and you'll see the focus confirmation indicator when you get close to being in focus, but not at the precise point where it is exactly in focus... and it will remain active across a small focusing range either side of the correct focus setting. Given the tiny depth of field we're talking about here, you simply can't rely on focus confirmation for accurate focusing.

Only areas of the subject that are in *perfect* focus will be free of glow and/or blur. Anything in front of or behind the exact focus distance, especially at fast apertures, will have some glow and/or blur. And if you move back or forth even the slightest amount while taking your shot, the point of accurate focus can change enough to throw the subject you thought you were focused on out of focus.

If you then add an extension ring for close focusing (as I believe you mentioned in an earlier post), the depth of field will become even narrower, and focusing even more critical. The glow, aberrations etc. will be even more noticeable.

Everything I've mentioned above is the same for *any* fast, telephoto, manual focusing lens, used on any DSLR camera that offers focus confirmation.

My experience was: pentax m/a 50mm f1.7, Helios 58mm f2 and other lenses but not with a fast aperture, so yes 85mm f1.4 it can be tricky... I will try more to shoot with this lens and to get better shots...