F-Mount Lens Notes

Some notes on these notes: When I talk about focus accuracy, I am generally referring to shooting sports such as college football, volleyball and basketball. My shooting conditions for these sports ranges from outdoors under bright sunlight through dusk and indoors under gym lighting. My gym recently received a lighting upgrade, which allows for available light shooting at ISO 800, 1/125, f/2.8 (this is an estimate and will be updated the next time I check the facility).

Sigma 8mm f/4

Fast on D2x, D200, D7000. Inherent depth-of-field provides leeway for focusing errors. Fairly sharp wide open, f/5.6 and f/8 provide a safe zone to eliminate any wide-open softness. Requires chromatic aberration correction for best results. In Camera Raw, start with -61 for red/cyan. Lightroom 4 era Camera Raw automatically corrects most CA, though some is still visible.

AF Nikkor 10.5mm f/2.8D (DX)

Fast on D2x, D7000. Ridiculously short minimum focus distance, allowing for steep perspective. In progress.

Nikkor 20mm f/2.8 AIS

In progress.

Nikkor 28mm f/2 AI

In progress.

AF Nikkor 35mm f/2D

Fast on D2x, D200, D70/D70s. Accurate wide open on most bodies, although low-contrast rendering and overall softness may create confusion. Focusing discipline required for best results. Clearer starting at f/2.8.

AF Nikkor 50mm f/1.8D

Fast on D2x, D200, D70/D70s. Accurate wide open on D2x, D200. Focusing discipline required on D70/D70s when wide open. Wide-open photos are somewhat low-contrast with an overall soft look. Much clearer starting at f/2.5.

Nikkor 50mm f/1.4 AIS

In progress.

Nikkor 50mm f/2 AI

The kit lens of the day for the Nikkormat. At f/2, overall softness lends a dreamy look to photos. Careful focusing reveals acceptable sharpness and fairly soft bokeh. Stopping down improves sharpness immensely. Maximum sharpness on D2x at f/8-f/11. Still sharp at f/16, but slightly degraded from diffraction. Don't hesitate to use minimum aperture if depth-of-field is necessary. Soft look at f/2 has great aesthetic potential.
 

AF Nikkor 85mm f/1.4D

Outstanding wide-open, and even better stopped down. I shoot studio portraits in the f/2.8-5.6 range and environmental portraits from f/1.4-5.6.

Fast and accurate on D2x. Off-center focusing is possible. So far, the D2x has been the most consistent in getting accurate focus.

Fast on D200. Off-center focusing is hit-or-miss. Fairly accurate with center AF sensor. Focusing discipline required in low-contrast lighting.

Fast on D7000. Higher resolution sensor requires more focusing discipline. Off-center focusing possible.

Fast on D90. Under moderate lighting, obtaining accurate focus at large apertures is difficult.

AF-S 300mm f/4

Fast and accurate on D2x. More focusing discipline required than with 80-200, particularly with moving objects, due to narrow depth-of-field. Sharp wide-open, and sharper stopped down. Subjects at extreme distances sometimes require manual tweaking (if available, focus manually in live view).

Less accurate on D200.

AF-S 300mm f/4 + TC-14

Effective f/5.6 aperture reduces speed and accuracy on D2x. Slightly soft wide-open, recommend f/6.3 as starting point. As usual with teleconverters, avoid unless closer approach to subject is not possible.

Tokina 12-24mm f/4 (DX)

Fast on D2x, D200, D70/D70s. Accurate on all bodies, although focusing discipline required to ensure proper subject is used to acquire focus (unintentionally in-focus backgrounds are more likely operator error). Slight softness wide-open may create confusion.

Chromatic aberration is complex and difficult to entirely manually correct. Good results with Kirk Douglas's D90 lens profile in Camera Raw. No problems with built-in profile from Lightroom 4 era Camera Raw.

AF Nikkor 80-200 f/2.8D

Fast and accurate on D2x, even in low to moderate gym lighting. Off-center focusing is possible. Moving objects track well.

Slower on D200 and D70/D70s. Off-center focusing is hit-or-miss. Less able to track moving objects. Under moderate to bright light, obtaining accurate focus is fairly easy.

Feel free to work at f/2.8, but be careful with focusing. A bit softer than smaller apertures, but still quite good. Great results at f/4-f/11.

AF-S Nikkor 18-70mm f/3.5-4.5 (DX)

Fast and accurate on D2x. Fast on D200, D70/D70s and D7000. Accurate throughout focal range. Focusing discipline a must at wide angle, wide-open, with busy backgrounds (unintentionally in-focus backgrounds are more likely operator error). Slightly soft wide-open at 18mm. Fairly sharp wide-open at 70mm. Sharp at f/5.6 for all focal lengths. Tracking moving subjects less accurate than 80-200.

Is this lens soft?

I was reading about this lens and a bunch of people said it was soft. Is it soft? I don't want a soft lens. I think I wasn't looking for the softness when I bought the lens, but now I want to know. I mostly print wallets and 4x6's from the kiosk at the store. You know, you put your digital memory card in and get prints in 10 minutes? I looked at my 4x6's with a magnifying glass to see if I could find the softness, but I'm not sure. I also looked at the photos at 100% and 200% on the screen, but I'm not sure. I just want to make sure this lens is sharp, because soft lenses aren't what good photographers want. Maybe I should sell this lens and wait for them to make a second version with improved anti-softness.

Why f/2.8?

A common question among new photographers concerns high-speed lenses. Why get the f/2.8?

Advantages of f/2.8 zoom lenses (14-24mm, 24-70mm, 70-200mm, 300mm, 400mm for Nikon users):

More depth of field control. A big advantage f/2.8 has over f/4 and f/5.6 is depth of field control. You can throw a background out of focus more easily with larger apertures. Consider the 50mm and 85mm f/1.4: Incredibly thin depth of field.

However, you must be careful in how you exercise that depth of field. In portraiture, it's generally preferable to have the subject's eyes in focus. With a couple centimeters that are in focus, it's easy to misfocus and have the ears in focus. Oops.

Focusing advantage. A larger aperture gives the camera's autofocus sensors more light to work with, generally enabling faster and more accurate autofocus. It's also easier to manually focus a fast lens because you can see what you're focusing on a little bit better.

The thinner depth of field comes back to haunt you, because it's easier to misfocus. If you're just a little off you're back to having ears instead of eyes in focus.

Optical and build quality. Generally, f/2.8 lenses are in the professional ranks of a manufacturer's product lineup. So they are among the top performers optically, especially compared to slower lenses. They are well-built, to take abuse from professionals who are really good at crunching them into rock faces or dropping them off waterfalls.

But, there are many slow lenses that are great performers. There are f/2.8 lenses with all sorts of weaknesses. Consider Nikon's 70-200mm f/2.8. Great on small sensors, but rather lacking on 135 format cameras. Consider Nikon's 18-70mm f/3.5-4.5. Its only real problem is vignetting at large apertures.

And many of Nikon's lower-end lenses can take abuse. I have kicked my 18-70mm around for five years and it's still going.

They're big. If you've got assistants and budget, you can carry five or six f/2.8 zooms. The rest of us have limited bag space and limited transportation space. Slower lenses are lighter and cover fewer cubic centimeters. I'd rather carry five pounds of gear than 10.

So basically, consider your needs and the limitations you'll encounter when planning a lens purchase. Everything in photography is a compromise.