You might think, “I read all the reviews before I bought my gear, so why should I test it as well?”
There are some things you need to understand about equipment testing:
- Many reviews are simply not very good;
- Lab reviews may not reflect your shooting conditions;
- Even field reviews may not reflect your usage;
- Equipment varies enormously.
Reviews done purely in the lab or the office (as many are) will not reflect real shooting conditions in the field. Every photographer uses their gear differently, so your particular usage may give quite different results.
When a magazine (print or online) does a review they almost always get only one lens or camera of a particular model to test. Almost all camera equipment (with the exception of some German lenses) is manufactured using the concept of tolerances. So if a lens element is supposed to have a focal length of 200mm, it may be manufactured with a focal length tolerance of 2%. What this means is that the actual focal length of the lens element may be anywhere from 196mm to 204mm. If all other lens elements have the same tolerance figure, then in a lens with five to eight elements the overall optical design can vary significantly. The same idea of tolerance applies to mechanical components, electronic components, etc. The result is that significant variations from body to body and lens to lens can exist on the same production line. So the lens you get, for example, can be anywhere from exceptionally good to exceptionally bad and still fall within the manufacturer’s tolerance values.
By doing your own testing you will discover exactly how it performs, for you, in the conditions in which you actually shoot, and in the way you actually use it.
Let’s look at how to test a camera body and a lens.
Testing Camera Bodies: With camera bodies we are interested in testing two main things: image noise and vibration profile.
To test image noise, shoot multiple sequences at each ISO setting of the subjects and in the lighting conditions you typically use. Why does this matter? Because the perception of noise varies greatly depending on whether the subject has broad areas of smooth tone or lots of detail, and on the overall lightness of the subject matter (noise is more obvious in darker than lighter areas). Put the camera on a tripod, start at the lowest ISO setting and shoot two sequences at each ISO setting, one with noise-reduction on and the other off (make sure you know which is which). Evaluate the results zoomed to 100% in various parts of the image. Then determine the maximum ISO that you can accept for different light levels and subjects. You can also decide whether the camera’s noise reduction gives you a better result or not.
To test vibration, you again want the camera on a tripod. Use a long-ish lens and frame on some subject with a lot of detail. Use the highest ISO and an aperture to give you a shutter speed of around 1/30 or 1/60 of a second, in aperture priority. Use a cable release or the self-timer. Steadily shoot while reducing the ISO so you get a sequence of shots at the same aperture. Then evaluate the sharpness in the center of the image when zoomed to 100%. What you should find is that there will be a certain shutter speed (or several speeds) at which there is noticeably less sharpness. This means you have found the shutter speeds at which mirror slap (in a SLR) and/or shutter movement vibration has lowered the image sharpness. If you don’t find this, try again at a range of shutter speeds higher or lower than you were using. Continue to use the same aperture in order to avoid introducing new variables that could affect the accuracy of the test.
Testing Lenses: With lenses we are interested in determining the sharpest aperture and how sharpness varies by focal length with zoom lenses.
To determine the sharpness characteristics, set up the camera on a tripod pointing at a scene that has a lot of detail, all at roughly the same distance and covering the frame from edge to edge. Use a cable release or self-timer to shoot a sequence of shots at each aperture and focal length. Use the ISO to make sure you avoid any problem shutter speeds that you determined earlier. Examine the center and corner of the images at 100%. Determine which aperture gives the sharpest result and if there are any that are so blurred you consider them unacceptable. You will also see how the sharpness varies by aperture. If you are a numbers type of person you can shoot resolution charts, but I find many photographers prefer to actually see how the sharpness varies on a subject they are familiar with.
You can use similar approaches to test other gear. For example, test your flash for evenness of coverage by shooting a white or even-colored wall at various zoom settings.
Once you know how your own gear actually performs you will know which apertures, focal lengths, lenses, ISO settings and shutter speeds you prefer. You will also have fewer negative surprises as you examine the results of your shooting.
Happy testing and happy shooting!
As photographers, we’re always concerned about how our images are reproduced, either on screen or in print. Sure, we learn about color management and how important it is to calibrate our displays and to use the correct printer profiles for output. But, how many of you have actually checked the accuracy of that output? Are you positive that your printer is giving you the best possible print in any given situation?
Most printers come with quality profiles for the paper that is sold by that company. HP is one of the few that I’ve seen that also offers profiles for popular third party papers as well. For the rest of your output needs, you’ll either need to find profiles, hopefully from the paper maker, or from a user group (Yahoo has groups devoted to almost every brand of printer). Or, if you’re the owner of an HP Designjet Z series printer, you can use the built-in spectrophotometer to make your own. The final option is to spend another $500 to $5,000 to buy the hardware and software needed to create your own profiles.
So, you’ve got the correct profile for your printer and paper, you’ve done your edits in Photoshop on your calibrated display. It’s as good as it’s going to get right? Maybe, maybe not.
Anytime I try a new paper, I go to the trouble of printing a test print to verify the quality of the profile for my needs. Many people will use one of their own images, sort of a benchmark, to do this. That’s fine and it gives you a good idea of how the printer does relative to other papers. But I find it useful to use a dedicated test file instead.
The advantage of using a test file is that it stresses all of the critical areas you need to be aware of when printing.
Test-file charts are available from a number of sources, but the two that I’ve found to be the most useful are from Uwe Steinmueller’s Outback Photo site and Scott Martin’s color and black & white charts. You can download these charts for your own use.
The advantage of using a standard chart is in having a known set of values. For example, you can evaluate how well your profile and printer produce gray ramps from white to black, color bars of different hue and intensity, as well as common subjects such as sky, skin tones. If you see problems, you can make adjustments prior to printing to get more accurate results.
Sure, it takes a little time, plus some ink and paper, but the overall time and cost savings can add up if the chart helps you find that your printer isn’t reproducing a particular range of colors as well as it could be.
I find it ironic that black and white imagery seems more popular than ever in the digital age. There’s just something about a strong monochromatic image that is more compelling than anything you can create with color. But obtaining a quality black and white from an inkjet printer has been frustrating, with many prints showing a color cast or significant bronzing.
While monochrome inksets are available from vendors such as MediaStreet, Jon Cone’s Inkjet Mall, and Lyson (yes, there are others, but these three have been the top-quality inks in my experience), new printers such the HP Designjet Z3100 have reduced or eliminated the need to go with a pure black and white printer. Obviously, not having a dedicated black and white printer saves money and space, but is the quality from the HP Designjet Z3100 really that good?
To find out, I made some comparison prints using this black-and-white image. For neutral tones, the HP printer was a clear winner with better tonal gradation and more neutral grays. Only when I went to a toned print did the dedicated inks show any advantage at all.
One area in which the other printers and inks couldn’t compete was the use of the gloss enhancer available on the Z3100. When printing to fiber or gloss media, the addition of gloss enhancer made a dramatic improvement, eliminating bronzing from the final print.
Part of the reason for HP’s high quality is that you’re essentially printing to a quadtone printer when using fine art media. The Z3100 uses both photo black and matte black along with the two grays. By not using any of the color inks, you eliminate any color cast that may otherwise be present. The only way to accomplish this with other printers is to replace the inkset with a dedicated monochrome inkset. This is costly and impractical when you also want to print color because you need to flush the ink lines with every cartridge change.
I am essentially lazy. I want to take great pictures at the start, then immediately go to print or the web with very little post production. That’s why I’m a digital purist and use color management to simplify my digital experience.
When I shot film, I looked for great light and always made sure I captured exposure that would produce a good negative or transparency. I was hard on myself if I had to rely on post processing to fix my mistakes. Even in the darkroom I liked to use the same few contrast filters for black and white printing. I was a film purist then and am a digital purist now.
As such, I have a mantra that really helps in dealing with digital imaging and printing: “Be Calibrated.”
Calibration is simply: To change the state of a device to conform to a known specification. It’s similar to a car tune up in which a mechanic checks how an engine is currently running, then makes the necessary changes to make the engine operate as it was designed to.
In the digital photographic workflow, I calibrate at every step. I calibrate my monitors with the Gretag Macbeth i1 to conform to a known luminance, gamma, and color temperature. When I shoot with my Nikon D200, I make sure I have calibrated to a known white point. I do this by setting a custom white point with a Gretag Macbeth White Balance Card.
Most importantly, when I print to my HP Designjet 130 and 90 I make sure that I use the “Automatic Closed Loop Color Calibration” feature on the printers. To see if there has been a drift in performance (which is a signal to re-calibrate), I send a copy of the test file shown here and compare it with a previous version. If the appearance of the colors has changed, I re-calibrate.
In every city in which I teach the Color without Limits seminar, one of the questions I hear most often is, “How often do I need to calibrate?” My answer is simple: “I re-calibrate only if I see a drift.”
A certain amount of drift occurs in all printers (and other digital color devices), no matter who makes them. Densities (and sometimes even hues) can change over time or when a new ink cartridge or printhead is installed.
It’s important to check for drift every time you set out to do a print run. Whenever I print, the first thing I do is print my test file. If it looks good, I am good to go. If it looks different than my last test print, I restart the calibration process.
Consistency is essential to managing color. Being calibrated means I can rest assured I will remain consistent.
The importance of being calibrated is that if I am calibrated, I have a better chance that my profile will produce satisfactory results.
Like I said, I am lazy. Really I am. I want to take great pictures and then make great prints with as little time in my digital darkroom as possible. So go on, be calibrated and I bet it will change your workflow forever.