Samsung 45mm vs Rokinon 85mm?

I'm thinking about picking up a new lens and the Samsung 45mm and Rokinon 85mm are the leading candidates.  I currently have an NX20 with the 18-55 III.  While it's OK, I don't think it has that wow factor that I'm hoping to get with the 45mm Samsung or 85mm Rokinon.  I also want something with excellent bokeh.  Obviously, the Rokinon doesn't have AF, but I can learn to live with that if the quality is worth the effort.

Having said that, if you have both lenses which one do you like better and why?

dgrogers wrote:

I'm thinking about picking up a new lens and the Samsung 45mm and Rokinon 85mm are the leading candidates. I currently have an NX20 with the 18-55 III. While it's OK, I don't think it has that wow factor that I'm hoping to get with the 45mm Samsung or 85mm Rokinon. I also want something with excellent bokeh. Obviously, the Rokinon doesn't have AF, but I can learn to live with that if the quality is worth the effort.

Having said that, if you have both lenses which one do you like better and why?

I have no rokkinon but Samsung 85mm 1.4, so with AF. If you're looking for bokeh, there is no better lens that 85mm 1.4. However taking picture at 85mm 1.4 is a challenging experience, esp. at closer distances (headshots). Actually i don't go below f2, leaving 1.4 for whole body portraits. I cannot imaging how anyone can take shapr picture with manual focus is subject is moving even a bit. 45mm 1.8 much more universal, much more forgiving and still a good lens for close up porttraits (headshots). I depends in what situations and scenes you want that bokeh.

I would probably chose the 45mm. It's versatile and gives you nice bokeh with auto focus only surpassed by the S lenses. Very reliable IMO

dgrogers wrote:

I'm thinking about picking up a new lens and the Samsung 45mm and Rokinon 85mm are the leading candidates. I currently have an NX20 with the 18-55 III. While it's OK, I don't think it has that wow factor that I'm hoping to get with the 45mm Samsung or 85mm Rokinon. I also want something with excellent bokeh. Obviously, the Rokinon doesn't have AF, but I can learn to live with that if the quality is worth the effort.

Having said that, if you have both lenses which one do you like better and why?

I have no rokkinon but Samsung 85mm 1.4, so with AF. If you're looking for bokeh, there is no better lens that 85mm 1.4. However taking picture at 85mm 1.4 is a challenging experience, esp. at closer distances (headshots). Actually i don't go below f2, leaving 1.4 for whole body portraits. I cannot imaging how anyone can take shapr picture with manual focus is subject is moving even a bit. 45mm 1.8 much more universal, much more forgiving and still a good lens for close up porttraits (headshots). I depends in what situations and scenes you want that bokeh.

I wouldn't get too close with the 45, it's kinda acceptable still for head shots, not too close though. Other than that I agree with everything you said, and I have both lenses. The 85 is not an easy lens to use even with focus peaking and the zoom aid for any subjects with any movement. I still did use it quite a bit more at an event though, because of the greater reach and faster aperture in awful lighting conditions. If I could only have one it would be the 45.

So there are a few thing to consider in this area. 
I like to think about things in Full Frame only because so many people I know and learn from use full frame and that is just how I think. 
the 45mm is just shy of 70mm and the 85mm is about 130mm. 
For portraiture 85mm is your start point for tight portraits. You wouldn't normally really use a 70mm unless you had no other choice. 
That being said a lot of those rules are BS to some extent here are two photos outtakes from a shoot a did a while back, one taken at 60mm one at 30mm (the 30mm I forgot to dial down the lights but liked the pose so I played with it.)

60mm on the left - 30mm on the right.  (outtakes don't judge me on these )

The 30mm is in tight neither photo is cropped or corrected in post. The Poses are similar, and they are filling the frame in a similar manner. Normal rules suggest a 50mm (ff) vs a 90mm (ff) should result in a noticeable distortion in the 50mm.

Because Samsung lens auto correct some of that distortion in camera it isn't such a big deal.

So from that point of view either lens will do the trick.

Both lens' are sharp (generally)

The 85mm is on my list because I like shooting further back from my subjects. To me that is what you should consider, do you like to be closer or further back? Also how wide do you want to see? How are you are manual focusing, will you be on a tripod most of the time.

Those are the questions to ask. Beyond that both lens are supposed to be very good.

Do a simple test, buy a cheap adapter and old manual focus 135mm f2.8 lens (pentacon, pentax, konica hexanon, whatever) and try using it. Adapter is around 15 usd and lens is around 25. It's f2.8 so DoF is twice the size of f1.4 but it's longer so background blur is similar. If you have trouble using it, just imagine razor thin DoF of f1.4...

Thanks.

I prefer to be further back, no tripod (though a monopod is a possibility), and tighter framing.  Basically, I like to capture people in the moment (without them necessarily realizing it) when they are doing something interesting or I think "that would make a good painting."

Eventually I will get both lenses.  Just not sure which one should come first...

Kaziklu wrote:

So there are a few thing to consider in this area.
I like to think about things in Full Frame only because so many people I know and learn from use full frame and that is just how I think.
the 45mm is just shy of 70mm and the 85mm is about 130mm.
For portraiture 85mm is your start point for tight portraits. You wouldn't normally really use a 70mm unless you had no other choice.
That being said a lot of those rules are BS to some extent here are two photos outtakes from a shoot a did a while back, one taken at 60mm one at 30mm (the 30mm I forgot to dial down the lights but liked the pose so I played with it.)

60mm on the left - 30mm on the right. (outtakes don't judge me on these )

The 30mm is in tight neither photo is cropped or corrected in post. The Poses are similar, and they are filling the frame in a similar manner. Normal rules suggest a 50mm (ff) vs a 90mm (ff) should result in a noticeable distortion in the 50mm.

Because Samsung lens auto correct some of that distortion in camera it isn't such a big deal.

So from that point of view either lens will do the trick.

Both lens' are sharp (generally)

The 85mm is on my list because I like shooting further back from my subjects. To me that is what you should consider, do you like to be closer or further back? Also how wide do you want to see? How are you are manual focusing, will you be on a tripod most of the time.

Those are the questions to ask. Beyond that both lens are supposed to be very good.

The NX20 doesn't have focus peaking.  How difficult is it to use with zoom type focus aid?

causey wrote:

DoF depends on focal distance too. One could get the same DoF with different combinations of aperture and focal distance. 85mm is significantly different from 135mm, imo...

I have the Rokinon 85mm, which I also had in Pentax mount before switching to Samsung NX. With a bit of practice and the help of focus peaking, it can produce great photos fairly easily. It is a better portrait lens than the 45mm, since it allows a more pronounced subject isolation at convenient "portrait" focal distances. But, obviously, it lacks AF, so if you need to click fast, pick the 45mm...

causey wrote:

DoF depends on focal distance too. One could get the same DoF with different combinations of aperture and focal distance. 85mm is significantly different from 135mm, imo...

The focal length of the lens or the distance from the subject? The focal length of the lens has no affect on Depth of Field but the distance from the subject does.

causey wrote:

But focal length also affects DoF. Keep aperture and focal distance constant, and change focal length: you'll get different DoFs.

No it doesn't. And, no, you won't.

causey wrote:

And yet DoF calculators disagee with you: http://www.dofmaster.com/dofjs.html

http://stefanlc.blogspot.com/

http://www.cambridgeincolour.com/tutorials/depth-of-field.htm

causey wrote:

emonstrated in the following chart:..."

To summarize: focal length "doesn't matter" as long as you change the focal distance. That is, you can obtain the same DoF with lenses of different focal lengths as long as you are willing to change the focal distance.

As DoF calculators show, DoF depends on three factors: aperture, focal distance, focal length.

Hope this helps.

Those are contradictory statements.

The truth is this:

Shoot a subject with a 50mm lens at f 5.6

Switch to a 100mm Lens and 5.6

Move back so the subject fills the frame to match the 50mm

The DOF will be the same. Only the distance has changed. The DOF looks different on longer lenses because the magnification crops out more of the image so you can't see all of the DOF.

https://luminous-landscape.com/dof2/

causey wrote:

Those are contradictory statements.

The truth is this:

Shoot a subject with a 50mm lens at f 5.6

Switch to a 100mm Lens and 5.6

Move back so the subject fills the frame to match the 50mm

The DOF will be the same. Only the distance has changed. The DOF looks different on longer lenses because the magnification crops out more of the image so you can't see all of the DOF.

https://luminous-landscape.com/dof2/

You changed two parameters, not one: focal length and focal distance. You say, "Shoot with a 50mm at 5.6, then switch to 100mm/ 5.6, move back; only the distance has changed,"--but if you want to prove that focal length doesn't affect DoF you should be able to say that only the focal length changed. However, you changed the focal distance in addition to changing the focal length...

More generally, if you want to see how a function of three factors varies when one factor varies, you must keep the other two constant.

Thus, if you want to see how DoF varies when aperture varies, you keep focal distance and focal length constant. Similarly, if you want to see how DoF varies when focal length changes, you need to keep aperture and focal distance constant.

It seems you're keen on contradicting me, which is fine, but if you are fond of arguing it doesn't make sense for me to try to explain anything. So, I guess, this is my last reply on this topic. I think you have enough elements to understand what I'm saying.

Now that you've successfully put an end to this argument, is there any chance you could respond to my inquiry about using the 85mm Rokinon without focus peaking?