Nikon 150mm aperture?

[gmed]

What is the sharpest f stop for the nikon 150mm for landscapes?

[BrianShaw]

Eleven (11)

[vinny]

sixteen

[Gem Singer]

There are two Nikon/Nikkor 150's. The f5.6 150W and the f8 150SW. Which one are you referring to?

Are you asking about "sharpness", or do you mean "depth of field"?

I usually shoot at f22, and adjust the shutter speed for proper exposure. That seems to be the f stop for the optimum image circle.

[E. von Hoegh]

The sharpest F stop from the point of view of diffraction would be 5.6.

[Matus Kalisky]

The sharpest F stop from the point of view of diffraction would be 5.6.

In theory indeed ;) But stopping down helps to eliminate many optical aberrations and large format lenses were/are often designed to reach optimal optical performance somewhere around f/11 - f/22 as those are the most used f/stops.

If you are talking Nikkor W 150/5.6 I would expect it to perform more than reasonably wide open - it is a modern lens after all (planar design if I am not mistaken).

EDIT: if you are not happy with the performance of your lens (based on the thumb-down) than make sure first that your focusing technique and film-holder/tripod/head/camera are OK as these are most often behind 'sharpness issues' :)

[gmed]

I have the 5.6. I mean the sharpest with max DOF without causing diffraction.

[Kevin Crisp]

If you are maximizing depth of field, the question is at what f stop you personally find diffraction too much. If I had to guess, the most common shooting aperture for landscape photographers is f:22, but in all but the largest prints f:32 will look just fine at a reasonable viewing distance. F:45 is fine with 5X7 but to me, the decrease in sharpness is noticeable in 16x20 prints from 4x5. Many fine 4X5 photographers, like John Sexton, use f:45 all the time, on the other hand.

Using camera movements to maximize sharpness enables you to stop down less than you would need to if you were trying to get everything sharp using depth of field alone.

[E. von Hoegh]

http://www.largeformatphotography.info/lenses-primer/


Have you looked on the homepage?

[Vaughn]

5.6, 11, 16, 22, HIKE! Go 49ers! :D

I use f64 and f90 most of the time on my Fuji W 300/5.6 -- but then I am working in the redwood forest where I have the need for the max DoF -- but I also contact print and the prints are sharper than one's naked eye differentiate.

Seems to me that if one is so concerned about sharpness of one's lens, a simple test of using it at different f/stops would answer any questions one might have about it.

Not all new lenses arrive in one's hands in perfect working order -- and used lenses could have been dropped or taken apart or put into another shutter without the proper spacing.

Vaughn

[E. von Hoegh]

I have the 5.6. I mean the sharpest with max DOF without causing diffraction.

Diffraction is present at all apertures.

[Gem Singer]

The Nikon/Nikkor f5.6 150W can be stopped all the way down to f64. However, f22 or f32 will give plenty of depth of field sharpness without the need to stop down to f64 where there is a greater possibly of diffraction.

(That's an anecdotal statement. I didn't find the need to stop down to f64 when using my 150W or my former 150SW in order to obtain sufficient depth of field).

[Walter Calahan]

always a hotly contested topic

the rule of thumb handed down decades ago from my teachers was "The sharpest aperture is usually somewhere in the middle of the aperture ring, give or take an f/stop"

my suggestion is not to stress about it, but instead use the aperture appropriate for your exposure needs

[ic-racer]

Two Nikkor 150s were tested here (http://www.hevanet.com/cperez/testing.html). In the center f16 is the winner on both. At the corners (of a 4x5 negative, not corners of the maximum image circle) f22 was the winner. So, you are both correct :)

http://www.hevanet.com/cperez/testing.html

Of course if you are not taking a picture of a flat test chart, the best aperture will be more of a compromise between diffraction and depth of field, and your 'best' aperture will usually be at a resolution below the best the lens has to offer. (See multiple articles on 'how to focus a view camera' and 'which aperture to use', etc.)

[Doremus Scudder]

My two-cents, since I'm logged in anyway :)

There is no simple answer here. As mentioned above, up to a certain point, there is a trade-off between quality (sharpness and contrast) degraded by lens aberrations, which decrease when you stop down, and diffraction effects, which increase when you stop down. These optimize somewhere between f/16 and f/22 for most standard-design large-format lenses. Most manufacturers give specs for f/22 (less often, f/16).

That said, this does not take the need for depth-of-field into account. With scenes that require a lot of DoF, there is another optimization that needs to be done between the degrading effect of diffraction (more the smaller the aperture) and the need to render near and far objects reasonably sharp (better with smaller aperture).

Included in this is the amount of enlargement you are planning on, or will find acceptable, as well as personal preference regarding the amount of degradation you find acceptable..... and so on.

I use the optimum f-stop method outlined here: http://www.largeformatphotography.info/fstop.html

It was not at all easy for me to dig through when I first approached it years ago, but I highly recommend taking the time to figure it all out. It is really not difficult.

I've now made "optimum f-stop" stickers for my cameras and use them all the time.

Hope this helps,

Doremus

[Matus Kalisky]

My two-cents, since I'm logged in anyway :)
...
I use the optimum f-stop method outlined here: http://www.largeformatphotography.info/fstop.html
...


That is an article definitely worth a read.

What one needs to realize that the f/stop at which the diffraction will become limiting factor in print sharpness is by how large factor will the negative be enlarged (contact print = 1, 16x20" from 4x5" = 4) AND viewed as it all boils down how many lines per millimeter are needed in the final print to look sharp.

In general 5 - 10 lines per millimeter should give impression of sharp image when viewed up close (10"). If such a print was produced as a contact print than the diffraction would indeed start to limit the sharpness at around f/128 (give or take).

But to get a sharp 16x20" from 4x5" negative the diffraction would kick in at around f/32 or so. For quick check the following calculator (http://www.cambridgeincolour.com/tutorials/diffraction-photography.htm) can be quite helpful.

[Jim Jones]

. . . I use the optimum f-stop method outlined here: http://www.largeformatphotography.info/fstop.html
. . . .

There's much good information there and in its links. There are the seeds of controversy, too. Lord Rayleigh's seminal research into diffraction limited optics is often taken to be the final word. We who have delved into one branch of diffraction limited photography (pinhole cameras) find his suggestion of optimum pinhole diameter is maybe 1/3 too large. It's difficult to give specific numbers because of the voodoo character of pinhole photography. Also, most discussion of circle of confusion assume that the circle is a sharp-edged evenly illuminated disc. If lenses really behaved like that, we wouldn't have the topic of bokeh to argue over. Maybe 60 years ago, before bokeh was ever discussed in English language literature, I read where some lenses were said to have a little more or less DOF than others of identical focal length and aperture. Such claims may often have been a proud owner's boast of equipment that miraculously outperformed that of his friends. Maybe there was truth to a few of those claims. Perhaps someone with a great variety of lenses and access to MTF analysis can finally settle these questions without relying on human error or invalid theory. Perhaps someday.

[pdmoylan]

I find that there are just too many images which require max DOF with movements with this lens to obtain optimum aperture consistently. I have wonderful results at f45 which I use fairly frequently. The sharpest aperture is the one that works to produce the results you need. 150mm is such a common FL but is very useful in the field for intimate landscapes where near to far DOF requires hyperfocal focusing along with front and perhaps back tilt and an aperture beyond f22. I cannot say enough about the consistent color quality and resolution I obtain from this lens from 1:5 through infinity. It loses some resolution at closeups from 1:5 to 1:2; however this is to be expected.