21 January 2012

Fallen Hoodoo at Toadstool Geologic Park, January 21, 2012

A fallen rock formation rests against a hillside in Toadstool Geologic Park, January 2012. (Photo by Daniel Binkard)
Toadstool Geologic Park is a wonder of western Nebraska, full of fascinating forms. The environment changes subtly each time you visit. It's an excellent place to work with foreground-background relationships. The large rock in the foreground weathers more slowly than the layer below it, resulting in mushroom-shaped formations that eventually topple. The line bisecting the foreground rock leads to the higher rocks in the mid-ground, and the scene culminates with a fluffy set of clouds.

Separate Autofocus from the Shutter Release

Note: This covers Nikon cameras, but many Canon cameras also have this option.

On just about any Nikon DSLR, you can set the camera to autofocus from a button on the rear of the camera, and make the shutter release only fire the shutter. This is a useful way to take an extra level of control over the camera.

Normally, the shutter release does double duty. A half-press engages autofocus, while a full press fires the shutter. In many cases, this works just fine, especially if you've grown up with autofocus cameras.

Separating autofocus control from the shutter release has several advantages, however.

If you grew up on manual focus cameras, locking the shutter release to just that one function may be more familiar. After all, manual focus cameras certainly have focus control separate from the shutter release!

By using a separate control for autofocus, you can maintain a high degree of control over when the camera engages autofocus. For focus-and-recompose situations, this is invaluable. Simply set focus with the rear button, release it, move the camera as needed, click the shutter.

Lightroom 4 Notes

The 2012 development process in Lightroom 4 contains a rethought workflow. I'm still getting my head around how each control affects the tonality of the photo. The refined clarity control stands out as being much improved. Even at high values, the halo effect on high-contrast edges is almost completely absent. This alone is reason to start using the 2012 process, and to look at reworking previous photos.

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.