Nikkor Z 85mm

[Lance B]

A stop is actually 1.4142 x (square root of 2) the previous lower or higher stop. So, the stop past f1.2 is actually f1.697 or f1.7. Here are the full f stop values and the rounded off ones we use:
f1
then it is f1.4142 - f1.4
then it is f1.999 - f2,
then it is f2.826 - f2.8
then it is f3.996 - f4
then it is f5.65 - f5.6
then it is f7.993 - f8
then it is f11.304 - f11
then it is f15.986 - f16
then it is f22.607 - f22

Half stop values are 1.2071 the previous stop.

 

[Larry S.]

Wow! The technical weeds are getting deeper…. The expression on my black bear’s face says it all..
… McStamp’s post has really generated some details on “f” stops….

What does he want to achieve with the 85mm lens? His question was whether the f/1.2 version was significantly better than the f/1.8 and worth the extra money. Probably not unless there is an expectation of tangible results that he needs or wants.

 

[Whiskeyman]

Wow! The technical weeds are getting deeper…. The expression on my black bear’s face says it all..
… McStamp’s post has really generated some details on “f” stops….

What does he want to achieve with the 85mm lens? His question was whether the f/1.2 version was significantly better than the f/1.8 and worth the extra money. Probably not unless there is an expectation of tangible results that he needs or wants.

In a lot of cases, the photographer is the weak link in the quest for better photographic images. There are still many reasons to go for the better glass if you can afford it, as it is possible for almost anyone to achieve tangible improvements with better equipment. It might lead one to improving one's skills so that more of the benefits of the better equipment is realized by the photographer.

 

[Anjin San]

It's made for that. Just watch focus, at 1.2 if you're 6 ft away, it's easy to get one soft eye. If I shoot it at 1.2 I'm typically magnifying the EVF and focus manually (Z9), and even then I check it on the computer monitor as I shoot (tethered).

I haven't shot with a 1.2 in a long time…but methinks that if you're getting one soft eye then going up in aperture a tiny bit would solve that problem while still keeping the soft background you're shooting the low aperture for.

 

[Whiskeyman]

A stop is actually 1.4142 x (square root of 2) the previous lower or higher stop. So, the stop past f1.2 is actually f1.697 or f1.7. Here are the full f stop values and the rounded off ones we use:
f1
then it is f1.4142 - f1.4
then it is f1.999 - f2,
then it is f2.826 - f2.8
then it is f3.996 - f4
then it is f5.65 - f5.6
then it is f7.993 - f8
then it is f11.304 - f11
then it is f15.986 - f16
then it is f22.607 - f22

Half stop values are 1.2071 the previous stop.

LanceB, the way I always look at it (and about the only way I can remember it) is to take the square roots of double the previous whole number square. Truncate to two figures unless the decimal is zero. If zero, drop the decimal.

1 - 1
2 - 1.414 (1.4)
4 - 2
8 - 2.828 (2.8)
16 - 4
32 - 5.7 (5.6)
64 - 8
128 - 11.3 (11)
256 - 16
512 - 22.627 (22)
1024 - 32
2048 - 45.255 (45)
4096 - 64
8192 - 90.51 (90)

Happy to muddy the waters further!

BTW My father was a math teacher, and every car ride was a math class and exam; for both my brother and me. And yes, we both ended up as geeks!

 

[Nimi]

I haven't shot with a 1.2 in a long time…but methinks that if you're getting one soft eye then going up in aperture a tiny bit would solve that problem while still keeping the soft background you're shooting the low aperture for.

Yup. That's what I do.

 

[wotan1]

I have the 85mm f1.8 as well as the 135mm Plena. I have not used the 85mm f1.2.

I originally bought the 85 1.8 because of its sharpness rating. I have always thought the lens was excellent and I tried to use it when I could. I am not however a portrait photographer.

The 85 1.8 does not have the shallow depth of field of the Plena nor does it have the background separation qualities. I tried to use it photographing foliage and flowers but was not able to easily get the results I wanted.

I would say if your primary interest is the focal length for portraits I would think the 85 1.8 is quite a nice lens. On the other hand if you are interested in what you can do with shallow depth of field and creamy dreamy background either the 85 1.2 or Plena is a better choice.

I think also the Plena is the Zen Master of subject separation and background rendering.

 

[Replytoken]

I dont know! All my photographic life i thought 1.2 to 1.4 to 1.8 is two stops, but i have no idea what that belief is rooted in! ChatGPT concurs, but it may be hallucinating.

Yeah, I had a fun time double checking myself, and the Ai results were similar to what you got, but as @JAJohnson detailed, AI produced incorrect results. But you did raise a couple of key points in your earlier post that the OP really needs to consider. The 1.2 does render differently, and the real questions are:

• How do the renderings differ?
• Does the OP prefer one over the other, and if so is the change worth the added expense and weight

I meant to include these in my earlier post, but sent it off too quickly. I know he's not everyone's cup of tea, but I found Thom Hogan's review of both lenses to be helpful reading. I am sure there are other factors to consider, but despite his grumpiness, his reviews tend to provide useful information.

--Ken

 

[JAJohnson]

I know he's not everyone's cup of tea, but I found Thom Hogan's review of both lenses to be helpful reading. I am sure there are other factors to consider, but despite his grumpiness, his reviews tend to provide useful information.

--Ken

Re: Thom Hogan I agree.

 

[SCoombs]

I have the 85 1.8 and have been happy with it. When I do school teams/individuals, I bring the 85 f1.8 for the individuals and the 24-120 f4 for the groups. I have no doubt the f1.2 is better and I may get it eventually, but it hasn't been something I have at all felt the need to spend an extra $2000 on yet.

You can only see EXIF info for this image if you are logged in.

You can only see EXIF info for this image if you are logged in.

You can only see EXIF info for this image if you are logged in.

I usually find the rendering/bokeh to be good. Sometimes it can be a little less good, but I would say that this happens in cases where the background was already perhaps not ideal for giving good bokeh.

Here is an example of that:

You can only see EXIF info for this image if you are logged in.

Here is how it can be improved with a simple background mask with the texture lowered:

You can only see EXIF info for this image if you are logged in.

Here is an example of "how far" the sharpness goes. First a full body shot, then a very extensive crop - down from 45MP to 3MP so you can see how sharp is looks after such an extreme crop:

You can only see EXIF info for this image if you are logged in.

You can only see EXIF info for this image if you are logged in.

Here is the closest thing I have to wildlife using this lens. This one has been denoised.

You can only see EXIF info for this image if you are logged in.

 

[Nimi]

Yeah, I had a fun time double checking myself, and the Ai results were similar to what you got, but as @JAJohnson detailed, AI produced incorrect results. But you did raise a couple of key points in your earlier post that the OP really needs to consider. The 1.2 does render differently, and the real questions are:

• How do the renderings differ?
• Does the OP prefer one over the other, and if so is the change worth the added expense and weight

I meant to include these in my earlier post, but sent it off too quickly. I know he's not everyone's cup of tea, but I found Thom Hogan's review of both lenses to be helpful reading. I am sure there are other factors to consider, but despite his grumpiness, his reviews tend to provide useful information.

--Ken

I dont shoot anything over 200mm. Under that, the 135, 85/1.2 and 50/1.2 render depth like no other Z, E, and RF lenses I tested. Similar to the Fujifilm GFX 110, and many Leica Summicrons, especially the APOs. Is it worth the extra cost and weight? I don't know, it is to me. I'm certainly going to jump on a 35/1.2.

There are several theories about why most modern lenses render flat or clinical images. The one I subscribe to, it's certainly my experience, is the inclusion of ED elements to reduce CA and getting away from certain glass chemistries. The three Nikon lenses are able to maintain sharpness, depth rendition and images generally devoid of defects using a very large number of elements, using special coatings as well as ASPH elements. That's why they are so heavy. Leica as far as I know (maybe Voigtlander) can get similar and better results in a much smaller package; they have to given the rangefinder configuration.

 

[KAC]

I have both lenses and use them regularly. Many times when I'm shooting large numbers of people for business headshots I'll use the 1.8 as I'm often shooting in controlled conditions at f4.5ish, and the difference between the two lenses isn't significant enough for clients to care. When I'm doing individual portraiture and will be shooting at 1.2, 1.4, etc., I'll use the 1.2.

There's definitely a quality difference between the two, and the question is will that difference reveal itself so significantly given the nature of the shoot that it justifies humping the heavier gear.

 

[John Navitsky]

i think it just depends on your priorities. if you plan to shoot fast moving things i’d probably go with the 1.8. if that’s not an issue it mostly comes down to if you need/want the faster aperture.

 

[Krümelkraft]

My contribution to the f-stop confusion

According to Krümelkraft, the correct f-stops (with 8 decimals) are as follows (from f/1 to f/2):

Since modern cameras can operate with 1/6 stops to be able to let the user choose between 1/2 stops and with 1/3 stops, we have to introduce 1/6 stops to get it right.
With those F1.2 lenses attached, Nikon camera displays show a "f/1.3" between "f/1.4" and "f/1.2" steps. We can therefore assume that "f/1.2" is a half stop faster than f/1.4 or one and a half stop faster than f/2 or one and a sixth stop faster than f/1.8.

 

[Roy]

I‘m evaluating a 85mm lens. The 1.8 is far cheaper than the 1.2, so I wonder if it is worth while spending so much more for more light. Has anyone some experience with one of these lenses?

I have both lenses and use them differently.
The 85 f1.2 is great for outdoor portraits where you need to lose the background.
Otherwise most of my studio portraits are at about f5.6 or f8 and the 85 f1.8 is perfectly adequate.
A bigger difference for most people would be to invest in lighting ...

 

[Jerry Heitschmidt]

One half stop slower than f/1 is f/1.19, which is rounded to f/1.2. Two thirds of a stop slower than f/1 is f/1.26, which by convention is rounded to f/1.2.

As an engineer this imprecision troubles me, but years ago I learned to accept it. In reality the difference between the two is so small it really doesn’t matter.

If my math is correct then an f/1.2 allows in 2x the light as an f/1.8, in theory. That said, I like the rendering of the 85mm f/1.8, its size and light weight. I also like the f-mount 105 f/1.4, but almost always leave it behind when I travel. That 85 f/1.2 is a chunky lens, so I am holding off on it…for now. Please keep us informed as to which way you go.

 

[EJDunn]

If my math is correct then an f/1.2 allows in 2x the light as an f/1.8, in theory. That said, I like the rendering of the 85mm f/1.8, its size and light weight. I also like the f-mount 105 f/1.4, but almost always leave it behind when I travel. That 85 f/1.2 is a chunky lens, so I am holding off on it…for now. Please keep us informed as to which way you go.View attachment 100522

Trying to make this as simple as possible, - in the old days of full stops (i.e. 1.4, 2, 2.8, 4 etc) there is one stop of light between each of these. My thought process is this, 1.2 is a third of a stop faster than 1.4 and 1.8 is a third of a stop faster than 2, therefore if there is one stop difference between 1.4 and 2, then there must be one stop difference between 1.2 and 1.8.

 

[Roy]

Trying to make this as simple as possible, - in the old days of full stops (i.e. 1.4, 2, 2.8, 4 etc) there is one stop of light between each of these. My thought process is this, 1.2 is a third of a stop faster than 1.4 and 1.8 is a third of a stop faster than 2, therefore if there is one stop difference between 1.4 and 2, then there must be one stop difference between 1.2 and 1.8.

Roughly right.
But just to complicate things -m F stops are not like T stops and are fairly arbitrary.
Especially amongst chinese lens makers where a lens may easily be up to a stop slower than specified ...

 

[SCoombs]

I'm not sure whether this is relevant/related to any of the discussion of the F and T stops going on here, but in testing some stuff with the Z8's metering (which I'll likely eventually write a post about) I have found an interesting behavior with the 85/1.8 in regards to how it behaves at different apertures.

Essentially, if I shoot this wide open at 1.8 it is very consistently metering a bit darker than if I stop it down to 2.8. The 2.8 shots are almost always metered 1/6 to 1/3 of a stop brighter - e.g., not moving the camera, same scene, same light, if auto ISO chooses ISO 1000 at 2.8 it will choose ISO 320 when at 1.8 when ISO 400 would be the equivalent exposure, or with a fixed ISO a shutter speed of 1/1600 at f1.8 might go to 1/500 at f2.8, yielding a 1/3 stop brighter image. When using auto white balance, it is also very consistently choosing a warmer color temperature at f1.8 vs f2.8 on this lens. I'm not sure what is going on with any of that.