Choosing Equipment

The best camera is the one you have with you when a photo opportunity presents. We are fortunate that mobile device technology continues to evolve to include capable cameras.

No one needs to be without a camera; it’s as near as their phone. All occasional photographers can use their mobile device cameras to become visual storytellers, capturing family scenes, portraits, short action videos, an occasional landscape, a closeup of a flower.

To move beyond point and shoot, support is available in online training tutorials for getting the most out of your camera phone and auxiliary equipment. The path to better pictures begins with exploration of the potential your equipment offers. Practice with it and work to develop instincts for good light and good composition.

When would one need more?

The pocket-sized camera phone will always have limitations when more power and control are needed, as for example:

  • For making large prints, more resolution may be required than the camera phone lens and sensor can provide.
  • For critical sharpness and contrast and saturation, for images with that extra punch, a more capable sensor and lens may be necessary.
  • For getting close to distant objects, more reach may be required than the camera phone lens can provide.
  • For low light situations, more capable exposure and flash capability may be needed.
  • For scenes with a large range from light to dark detail, more dynamic range may be required of a sensor.
  • For more control of image parameters affecting depth of field and exposure, access to manual control of more camera functions may be required.
  • For action photography, more capable focus, shutter speed, and imaging speed may be required.

Some of these shortcomings may be corrected with future technology. Thus the mobile device camera may largely obsolete the point and shoot cameras that in the past have marked the usual entry point to photography. Yet we understand that image quality is dependent on light-gathering power and resolution, which depends on size of lens and sensor, so  larger lens/sensor assemblies will always be a prerequisite for best quality.

Single lens reflex (SLR) technology has fulfilled this role over the last century, currently called the Digital Single Lens Reflex (DSLR) camera. DSLRs have a mirror that descends into the optical light path between lens and sensor and reflects some of the light to a prism and then into the optical viewfinder. This allows the photographer to see exactly what the lens sees while composing the image and previewing exposure and focus. An instant before the shutter is actuated, the mirror flips out of the way to enable all the light coming through the lens to fall on the sensor.

There is a new, simpler approach coming around the bend. Mirrorless cameras with through-the-lens electronic viewfinders are preparing to challenge the reign of the DSLR. They offer interchangeable lenses in compact packages and are gradually migrating to larger DSLR-sized sensors and lenses. They cost less than the DSLR, but still lag in features and capability.

Below I will discuss the Nikon products I am familiar with; Canon and others offer competing visions and products. Rather than an exhaustive discussion of what is available, I will simply state my own selection process, which is instructive neither of what to do, nor of what not to do, but rather as a catalog of things one might consider.

Nikon Camera Terminology

I am a typical amateur photographer, at best advanced novice level. Nikon makes a line of cameras and lenses for such typical needs. But I have a psychological need for the best tools I can afford, which drives me to equipment that likely exceeds my discernment needs and skill set. This extra investment helps motivate me to become the best technician I can be, to increase my skill set. It further opens the possibility that, through occasional luck, I may exceed my capabilities and produce a fully professional result, not limited by compromised tools.

As with the other vendors, there are two main Nikon camera lines distinguished by sensor size: full-frame (FX), and crop-frame (DX), also referred to as APS-C (named after a now defunct Kodak film standard Advanced Photo System). The diagonal of the DX sensor is .65x that of the FX sensor. The choice of FX or DX body is dependent on one’s photography interests. It is part of one’s photoID.

The latest Nikon autofocus technology is called AF-S, where the S indicates Silent Wave Motor. Nikon has settled on the term vibration reduction or VR for its in-lens optical image stabilization. This is now the second generation of VR. Initially called VR II, it now is simply VR again.

Camera Selection

Nikon’s early forays into digital photography were all DX format. I owned the D1, D2H, and D300, all purchased used. These were professional and semi-professional cameras, very pricey when new. But with technology advancing rapidly, their depreciation was precipitous. By lagging behind the state of the art by a generation or two, such toys fell back easily within my budget range.

My limited technique, coupled with my equipment limitations, coupled with my questionable choice of birds as my favorite subjects, caused me many more whiffs than hits. Excuses are many. I am stubborn and lazy and don’t want to lug a tripod, so I make do with hand-held photographs – strike 1. Birds are most visible early or late, and the autofocus could not work well enough in dim light – strike 2. If the ISO was in the quality image range, the shutter speed often dropped too low – strike  3.  If the ISO was raised high enough to enable a successful shutter speed, unacceptable image noise would result – strike 4. If a bird with white markings (e.g. bufflehead duck) appeared in bright sunlight, the sensor could not handle the subject’s dynamic range – strike 5.

To try to get a few more keepers, I recently upgraded from my D300 to the current top-of-the-line Nikon D7200 DX camera body. The DX line of bodies no longer numbers among the Nikon professional line, which are now all FX. But the D7200 is weather-sealed and comes with a magnesium internal frame. (Access to the innards requires unscrewing the polycarbonate bottom plate and then the magnesium rear cover.)

D7200_18_140_front34lbody

Note on build quality: I dropped this camera recently. It bounced 4-5 times down a steep rock embankment, until a small tree stopped its descent. The battery door popped off and the lens hood was jammed down on the lens barrel, pushing up the rubberized zoom ring cover. Watching it fall so roughly, we were sure it was a goner.

Yet the hood popped back in position, the battery door popped back on, and I resumed shooting. It never skipped a beat. And it only has two small marks on the body that one needs a magnifying glass to see. Thank you Nikon, for protecting my investment through rugged quality.

Upgrade Rationale

While I miss the feel of the semi-pro D300 body, the performance and build quality of the D7200 restores a smile to my face. There were many points to my upgrade rationale. In 2007, the D300 introduced the EXPEED processor and Multi-CAM3500DX AF sensor. The 2015 D7200 offers the 4th-gen EXPEED and 2nd-gen Multi-CAM processors. The shutter specifications are identical for both cameras, but the D7200 sensor offers double the pixels and 3EV more dynamic range. And it is a half pound lighter.

Sensor Quality (measured by DxO):
Camera               Score    Max Dynamic Range (EV)    Max Color Depth (bits)
D7200                    87                    14.6                                              24.5
Sony A77 II           82                    13.4                                              24.4
Canon 7D II          70                    11.8                                               22.4
D300                      67                    11.6                                               22.1

DxO rates the 7200 24.2 mp sensor the sharpest, most capable APS-C sensor to date.
It uses no anti-alias filter for additional sharpness.

ISO Sensitivity:
Camera      ISO Range        Max ISO For Critical Quality*
D7200        100-25600                      1333
D300          200-3200                         679

* Max ISO that provides at least 18 bit color depth, 9EV dynamic range, and 30dB SNR

Autofocus:
Camera   Focus Points     Min Light      Min Aperture (Center Point Focus)
D7200            51                        -3EV                                f/8
D300              51                        -1EV                               f/5.6?

Exposure Metering:
Camera               Matrix Type
D7200         2016 pixel RGB 3D matrix
D300           1005 pixel RGB 3D matrix

Continuous Exposure Buffering (14-bit RAW images):
Camera    Max Frames/Buffer        Max Frames/Sec
D7200                18                                         6
D300                  17                                        2.5

Battery Life:
Camera             Images/Charge
D7200        1110 images or 80 minute video
D300          avg. 500 RAW

The D7200 Adds Functionality:
video (1080/60p) with time lapse
stereo mic
HDR mode in-camera
built-in wireless connectivity
built-in NFC
flat picture control
U1, U2 Instant Recall

The D7200 Enhances Usability:
faster processor
rear LCD with greater resolution
smaller and lighter (saves 1/2 pound)

Wireless Operation

There is a Nikon remote app for iPhone. It allows the iPhone to access the camera’s memory card and to view/transfer its images. It further allows the iPhone a live view of the current scene through the lens, and a remote shutter activation. Consequently, the D7200 does not provide the standard 10-pin terminal for using old style remote shutter release cables.

Lenses

The latest Nikon zooms are magical, equaling or besting my fast older manual focus Nikon prime lenses in sharpness, contrast, and freedom from optical anomaly. In addition to the convenience of zoom operation, they offer AF-S, VR, and much better glass and coatings. Their image quality and usability have largely rendered my collection of primes as relics, unless a special situation arises where a very fast lens with close focusing is needed.

Nikon lenses are now distinguished for FX or DX use. FX lenses can be used on both FX and DX bodies, but DX lenses are only useful on DX bodies. Several ‘experts’ advise against using FX lenses on DX bodies, because the extra expense and weight of the FX lens is wasted excess on a DX sensor (and presumably on me). I rely on the experts opinions a lot, but I find such preachiness unbecoming of a professional.

I hold an opposing view. I want only lenses that provide the best theoretical performance at a cost I can justify. And FX lenses provide their best corner to corner performance relative to DX sensors, performance that bests any available equivalent purpose-built DX lens. Thus I own only FX lenses; sorry experts.

Anyone who shoots a lot of wide angle images likely uses an FX body rather than a DX body for this work. DX favors the long tele range. On my DX body, I am happy with an 83° field of view with the wide zoom, but this same lens on an FX body gives a 107° FOV. For my use, 83° is sufficient.

I currently use three late-model zooms: wide (16-35mm), normal (35-85mm), tele (80-400), breaking with the conventional notion that only one or at most two zooms are necessary. The normal zoom is weaker at its wide end; the wide zoom covers these focal lengths with better results.

The normal zoom is my portrait close-up lens. The tele zoom is my bird/wildlife closeup lens, and my flower/insect closeup lens when the Canon 500D closeup adapter is mounted on the front. I went through Shaw’s Landscape Photography and did a  rough count of which focal lengths he used for his example photographs: ultrawide (1), wide (45),  normal (49), tele (42).

It appears my three zoom lenses should handle virtually all of my photographic needs. Landscape photos will use these lenses about equally. Portraits and other closeups will use the tele lenses almost exclusively. I currently still own the Nikon DX 12-24mm ultrawide, but like Shaw, I seldom find a use for such a short focal length.

Shaw used a tilt/shift lens for ~8% of his book’s images. This would be a more important addition to my kit than keeping the ultrawide, a good trade-off. My FX lenses may be over-designed for a DX sensor, but they cover my FOV requirements. And because they cover the smaller sensor by the central part of the lens, they deliver exceedingly fine results.

While there are several Nikon lenses that would cover the wide-normal focal lengths in a single lens for much less money, using these two different lenses gives me sharper results. Can I see the difference? I don’t know, and I am not going to tire my aging eyes by exhaustive comparison. Suffice to say, some eyes at some reproduction scale will be able to see it, and then the images will do me proud.

Wide:     AF-S 16-35mm f/4  VR FX

16-35

  • 17 elements in 12 groups
  • 2 ED and 3 aspherical elements
  • 107° – 63° (83° – 44° with Nikon DX format)
  • nano crystal coating
  • min focus 0.29m
  • 680g

Normal: AF-S 24-85mm f/3.5-5.6 VR FX

24-85

  • 16 elements in 11 groups
  • 1 ED and 3 aspherical elements
  • 84° – 28°30′ (61° – 18°50′ with Nikon DX format)
  • super-integrated coating
  • min focus 0.38m
  • 465g

Tele:       AF-S 80-400mm f/4.5-5.6 VR FX

80-400

  • 20 elements in 12 groups
  • 4 ED and 1 superED element
    • 30°10′ – 6°10′ (20° – 4° with Nikon DX format; – 2°50′ with 1.4x teleconverter)
  • nano crystal coating
  • min focus 1.75m (0.5m with 500mm, 2-diopter close-up lens)
  • 1480g

Why select these semi-pro class FX lenses? I do not need the weight and expense of the fast professional line of lenses. I seldom need to freeze action in low light. But I do want equivalent accuracy. Because of their superb contrast, color performance, and top-shelf resolution, these slower lenses represent the best value to me. The 16-35mm ois comparable in sharpness and contrast to the much pricier 14-24mm, although it is 1 stop slower. But VR gives it at least a two stop advantage over the faster lens in my hand-held shooting style.

Accuracy is represented by a metric called  modulation transfer function (mtf), the ability of the lens to render contrast and detail. Nikon publishes measured mtf for these lenses across their 16mm-400mm focal lengths. Each value represents the theoretical approach to perfection (1.0) of the transmitted image.

The accuracy will generally be maximal at the center of the image, with the lens stopped down one or two stops. The precise focal length producing the highest mtf is called the sweet spot of the lens. However, I am interested here in characterizing the lens’ most compromised  performance areas, usually with aperture set wide open, and with mtf measured at the DX edge of the frame (15 mm from center). Thus these are the worst performance specifications for these lenses, not the best.

The mtf is given by Nikon as a set of four values (S10, M10) (S30, M30). These four measurements comprise two test image line directions, S=sagittal and M=meridional, and two spatial frequencies:

  • 10 lines/mm (measuring contrast, how the lens transmits light/dark color transitions occurring at lower spatial frequency)
  • 30 lines/mm (measuring detail resolving power of the lens at higher spatial frequencies).

The first measurement pair is indicative of preserved scene contrast in the transmitted image, and the second measurement pair indicates the capability of the lens to preserve the finest details in the scene. Here are the results for the lenses above, with FX equivalent focal lengths in brackets:

  • 16mm [24mm]        (.99 .95) (.94 .58)
  • 35mm [52.5mm]     (.95 .94) (.59 .66)
  • 85mm [127.5mm]    (.96 .92) (.77 .62)
  • 400mm [610mm]     (.96 .96) (.72 .72)

These mtf values are the best I could find among Nikon lenses at these focal lengths. All these lenses have mtf >= .9  wide open, measured at the center, except the tele, whose fine spatial resolution at the center is .85.

There are other characteristics of lenses that affect quality, mainly color accuracy  and different types of distortion. But these are usually easily overcome, either in camera if JPEGs are being output, or with post-processing software for RAW image formats. While some zooms can introduce complex, periodic (wavy) distortions and focus deviations that cannot be removed after the fact, this will never happen with high-quality zooms such as these.

Auxiliary Lens Hardware

Filters modify light characteristics before the light reaches the film or digital sensor. They typically screw onto the front of the lens. External filters were important for film cameras, but with digital sensors, the digital image file can be processed with software to modify post-exposure light characteristics for desired effect. Obviating the need for some post-exposure processing, digital cameras utilize built-in filters.

There are add-on filters that can be useful on a digital camera for added light control. I have one of each of the following multi-coated, 77mm filters. I add such a filter only for a specific condition I want to address;  otherwise, they are off the lens. I have a 72-77mm step-up ring, so that all three of my zooms can use these 77mm filters. These filters can be stacked as appropriate for any exposure need.

  • UV (Nikon L37C) – provides a lens protector for harsh shooting conditions, such as wind whipped moisture, sand, or salt, or when risk of falling is severe during rough scrambles with loose footing (which once cost me use of an unprotected lens).
  • Polarizing (Nikon CP, and HN-29 hood for when used on telephoto) – removes direct sunlight reflections from water and other naturally reflective surfaces; improves contrast and color saturation, particularly when the sky and/or green foliage is part of the scene.
  • Neutral density 1.8 64x 6 stops (Haida Slim Pro II)  – puts sunglasses on your camera, allowing a longer exposure that can assist with capture of motion effects, such as in flowing water, wind on water or grass, etc.
  • Graduated, rotating, neutral density 0.6 8x 3 stops (Tiffen HT) – tames a bright section of a scene covering less than half the frame, to improve overall exposure

Note my UV filter is not necessary for UV filtering, which is already done by the camera’s internal filter stack at wavelengths below 425nm. Note also that the popular 81B warming filter and other color tweakers are not necessary, as white balance adjustments are offered in any competent image editor in post-processing. If no post processing will be done, in-camera WB controls can safely duplicate the effects of such filters for mild color tweaks. For any large color shifts, noise may be introduced in some color channels in the digital domain. Such a large shift would still be best served by an external color filter.

Adding extra glass elements to the front of the lens could slightly degrade image quality, but for a quality, multi-coated glass filter, there has been no demonstrated loss of quality except in extreme cases that would be prone to lens flare anyway. In such cases, a flare or ghosting may be exacerbated by the presence of a filter.

A Teleconverter Lens fits between a long lens and the camera, extending its focal length. In my case, the extension is 1.4x, extending my telephoto lens to 560mm, while decreasing lens speed to f/8. VR still works and the D7200 supports autofocus with one sensor at f/8. I chose the Kenko Teleplus Pro 300 as my focal length extender. It is multi-coated and has 5 lens elements in 2 groups. I use a monopod with this length. The teleconverter is only of use for stationary subjects in better light.

A Close-up Supplemental Lens allows a long lens to focus within inches of a subject. I chose the Canon 500D closeup adapter, a multi-coated, two element diopter that screws onto the front of a lens.

A set of Extension Tubes permits further improvement of a lens’ closest focus distance. I have the Kenko 12mm, 20mm, and 36mm stacking tubes.

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