I was recently approached to update the employee images on the website of a local business. Normally, this type of project doesn't give one much latitude for fun or experimentation. If you browse your run-of-the-mill business site you generally come across staid and safe profile pictures. I didn't want to spend a day running people through a photo mill and do a lot of post on images that all looked alike - that type of project seems like it's bad for the soul. And, luckily, I'm in the position where I don't have to take a job if I don't think I'll enjoy it. For me, this is just a hobby; photography by far costs more than I make from it, so I can reply to said business and offer them my idea for how to do the portraits and if they don't like what they hear c'est la vie and move on.
My idea was to do away with generic backdrops and use paintings, other art, or furniture from the office as the background. Also, I wanted the option to incorporate more candid shots - if a person was looking away in contemplation, for instance, and I captured something compelling there, I wanted the option to use it. Or, as it turned out, if someone were engaged in real and spontaneous laughter and if it made a good image, I wanted the ability to use it as well. The point was I wanted something different, but still professional in feeling and execution.
They liked the idea. This is Austin, of course, so the odds of you coming across a business that appreciates the idea of trying something new are probably better than your average city. Their old site had traditional portraits set against that one blue muslin that seem to be given away every time you open a bank account or something - you know what I'm talking about.
However, there is always one problem when dealing with employees - they are not models. I can talk all day preparing them for natural and candid shots, but once the camera comes out people more often than not clam up and start doing their approximation of a portrait pose or smile and the effect can be unnatural, if not unexpected. This happened often, let me tell you.
If I was having a hard time getting what I thought was a natural pose, I would do my best to coach something out of the subject. I could have them lean back to get comfortable, and fire off a series of images WHILE they formed their smile. It seems that when people start to do their "portrait smile," somewhere during the process they make a face that feels far more natural to me.
So, safely in their everyday environment, I would start each person's portrait with a conversation to get them used to seeing me and seeing the camera. During our talk, the camera would come up and I'd fire off a pic or two.
It's a process that seemed to take most of the edges off the "portrait taking experience" and give me something to work with.
And sometimes, it really showed off the subject's personality.
This was all well and good, but working in a limited environment for backgrounds, it didn't take long to run out of things to pop behind people. So I decided to use some background ideas more than once, changing up how I presented them.
For example, this office had nice large windows that overlooked the Texas Hill Country. As pretty as that is, it was going to get boring soon if the same stretch of grass and trees were behind everyone so I chopped up the scene. I shot one looking down onto a highway:
And another up towards the horizon:
And then, to completely maximize a location, I blew out the light from the window and high keyed the image:
That's three very different portraits taken from the same window. Not a bad use of limited resources if you ask me.
When we were done we had a collection of diverse imagery that complimented the employees and the resulting website looked unique and professional. More importantly, the client was happy.
The problem of filtration when using ultra wide-angle lenses with bulbous front elements has been a thorn in the side of photographers wishing to take advantage of these stellar optics. As a whole, these lenses are never threaded for filters as the front element's convex construction prohibits threads. The hoods for these lenses are usually fixed, as well, and given their unique nature, makes it impossible for a single holder system to work on all variations without significant modifications to the holder for each different lens.
I came across a DIY describing how an intrepid photographer was able to adapt a Lee Filters SW-150 150mm filter holder onto his Samyang 14mm ultra wide-angle lens. (Currently, the Lee SW-150 filter holder is made only for the Nikon 14-24mm f2.8.) The process, however, mangled the scarce and expensive filter holder and there was still the problem of there being no circular polarizer that was currently available for the 150mm system. (Some have adapted circular polarizers meant for other applications for use with the SW-150, however.)
Formatt-Hitech make a system for ultra wide-angle lenses that have several adapters for various lenses, including the popular Samyang 14mm. The Hitech LucrOit system looks to be a well though-out solution, but until recently it was very difficult to find the product in stock. After playing the Lee Filters stock game I wasn't looking to double down on that particular experience. The LucrOit system also does not allow you to mix square/rectangular filters and circular threaded filters. In fact, there are no threaded filters available for the system, period.
Enter Fotodiox. This American company, based out of Illinois, developed a near complete system for fixed hood, bulbous front element ultra wide-angle lenses called WonderPana 66. Reading the description, I became excited.
The WonderPana 66 System
The WonderPana 66 uses a base kit specifically designed for a lens to mount circular, double-threaded filters which Fotodiox call the WonderPana 145 Core Unit . Onto this foundation one can optionally install a rail kit, called the WonderPana 66 Upgrade Bracket. This bracket allows you to install either two rectangular filters or one screw-in filter and one rectangular. It's made of aluminum and attaches via thumb screws so you don't need tools when you're out in the field.
Unfortunately, the thumbscrews that tension the rectangular filters in the Upgrade Bracket are of a different length than the thumbscrews that mount the bracket to the Core Unit. This has the potential to frustrate if you are looking for one type and pick up the other, which apart from slight length difference appear nearly identical. The longer filter tensioning screws will not work as bracket mounting screws. The tensioning itself is not unlike the way the Schneider/Century Optics variation of the Lee Foundation Kits secure slide-in filters and it works very well. (If only Lee would adopt something similar to their basic foundation kit, but I digress.)
WonderPana attached to a Nikon 14-24mm and a Canon 5D Mark III
The Core Unit is novel in both its method and construction. Other methods for attaching large filters to lenses not designed to accept filters might require the user to push on the foundation holder, similar to the way you push on a lens cap for slim filters that have no front threads. This method can be secure, to be sure, but the Wonderpana system uses threaded collar that slides over the back of the lens and screws into the front of the unit resulting in a very positively locked system, similar to Lee's SW-150 holder. All of the Wonderpana components, however, are made of aluminum.
Rear view of the WonderPana system. The red collar screws to the front of the unit clamping down on the fixed filter hood.
Onto this core attaches the rail bracket with brass thumbscrews. In the above picture I used four total but there are holes for six. The small thumbscrews are fiddly to work and would be very difficult with gloves on. In fact, attaching the bracket is best done where you have a clear surface to work on. Out in the field this entire operation could prove nerve-wracking - balancing the lens and collar, lining up the holes, screwing in the thumbscrews while keeping the two pieces, lens collar and bracket, from moving. Once you get one thumbscrew in, however, the rest of that side is a piece of cake.
For scenes where you'd like to place the ND grad transition line at an angle, it is possible to rotate the bracket about the core unit but you're limited to rotating in 45° increments. This isn't ideal, but it sure is better than having to compromise your placement by only being able to work with perfectly horizontal transition placement. To rotate the rails you must unscrew them from the core unit and re-mount them in the angled configuration. There are another set of mounting holes for this.
WonderPana vs. Singh-Ray 4x6 filter comparison.
The WonderPana's rectangular filters are HUGE. We're talking 168mm wide huge. In comparison, the Lee SW-150 filter holder accepts filters that are 150mm on the wide side. The estimable and popular 4x6 filter, above, looks like a Cokin P compared to the WonderPana.
Not only are the WonderPana filters large length and width-wise, but they are also thick. Hitech's Lucroit filters are 3mm thick and that's already pretty robust. WonderPana filters are 4mm thick and unless you hold it in your hands you might not have an appreciation for just how much filter that is. Lee's 150mm filters are like their 4x6 filters in this regard, half as thick at 2mm.
The WonderPana rectangular filters are multi-coated (!), which makes them unique among this large class of filter, and made from organic glass called CR-39 or "optical resin." If you wear corrective lenses, optical resin is the material the lenses are probably made of. Plexiglass is also a type of organic glass. CR-39 is a high quality transmissive material that's cheaper and lighter than glass but won't (read: shouldn't) shatter when dropped.
The system comes with a complete line of standard neutral density filters, 4ND, 8ND, 16ND, and 32ND in 145mm screw-in configuration, and four graduated neutral density filters, 2 and 4-stop versions of both hard and soft graduation. There is also a clear protective UV filter and a circular polarizer in 145mm available. To top it off, Fotodiox include a 145mm lens cap to protect that precious front element when the system is attached without filters. All of the components come very well appointed. The rectangular filters come in large foam-reinforced nylon zippered pouches that are plush on the inside. For some reason there is also a mesh pocket on the inside of these pouches. I suppose you can keep a microfiber cloth in the pocket, but a microfiber cloth doesn't need a pocket to be stowed. I find that the pocket catches the filter when the filter is slid in more times than not. The internal pocket annoyance is one quick scissor procedure away from being corrected. The screw-in filters ship with nylon pouches similar to the blue B+W pouches that Velcro close. The hardware components, the core unit and bracket, ship in zippered hard clamshell pouches with flocked foam fitted inserts.
WonderPana 145 2-stop neutral density filter.
Looking at the 145mm ND filters one notices that the reflected color of the filter themselves changes rather dramatically from the 2-stop to the 4-stop. The color of the 2-stop is bronze while the 4-stop is greenish.
WonderPana 145 4-stop neutral density filter.
It's not clear if Fotodiox make these filters in-house or outsources some or all of them. Interestingly, the 145mm circular polarizer is labeled "XS-Pro" on the ring. XS-Pro is B+W's designation for their slim form digital filters that are thin for ultra wide lens use yet retain front threads for filter stacking or a lens cap. Do B+W make at least the 145mm circular polarizer for Fotodiox?
Regardless, there is a reassuring physical quality to both the 145mm screw-ins and the 168mm rectangular filters. There is no play between the glass and the filter ring that I could detect. The ring of the circular polarizer rotates independently and does so smoothly but not loosely - it stays where you rotate it - similar to high quality rings from B+W and Singh-Ray.
But how do they perform?
Baseline Lake Image
Using a Canon 24-70mm Mark II mounted on a Canon 5d Mark III, here is the scene without filtration or processing of any kind. (Was it too difficult to get some clouds?)
Singh-Ray 2-Stop Soft Grad
Here's the same scene with a Singh-Ray 2-stop soft graduated neutral density filter. In attempts to create as level a playing as practical using two such different sized filters, I slid the Singh-Ray down into the scene until the meter went from 1/1250th of a second, which is where the baseline image was taken, down to 1/640th of a second and immediately stopped and took the picture.
WonderPana 2-Stop Soft Grad
Using the same method, I slid the Wonderpana 2-stop soft graduated neutral density filter into the scene and stopped when the meter hit 1/640th of a second. It's not scientific but it is illustrative for our purposes.
The scene is remarkably similarly rendered.
Singh-Ray 2-Stop Soft Grad
WonderPana 2-Stop Soft Grad
After a predictable corralling of the blues in the skies you can see that the filters were slid down enough to affect the greens in the trees, too. The Singh-Ray brought more into the midtone region, note the green channel, than did the WonderPana. Both affected the highs in much the same way if they are not nearly identical.
Here's a more chaotic baseline scene. The scene has a smattering of detail, a great area for testing the polarizer, and it blows out through the trees. The should give us some convenient examples for comparison.
WonderPana 145mm Circular Polarizer
This is the same scene with the WonderPana 145mm circular polarizer installed. Notice the reflection on the siding of the house in the upper left corner.
Baseline Corner 100%
WonderPana Circular Polarizer Corner 100%
I was concerned that a multi-coated 145mm circular polarizer that costs $120 would create some problems with resolution and sharpness. After all, quality multi-coated circular polarizers in 82mm can cost over $250! We're talking 63mm more filter for $130 less.
Mind you, this area of the image was outside of the polarized band that affected the siding reflection. (On extremely wide angle images, polarizers cannot affect the entire image. This usually creates a noticeable band of polarization over just a portion of the image.) However, the lines of the leaves are well maintained with no noticeable amount of resolution lost.
This is significant because in this area of the image light has to travel at an angle through the filter that is most extreme, so light goes through more filter glass at the edges than anywhere else in the image, if only very slightly so. If there are going to be imperfections, they should be most pronounced in this area.
WonderPana Circular Polarizer
There are no painful shifts in color. Many circular polarizers like to cool scenes down. Not so much here. The blues are nearly cemented in place. Corrected for light lost, there is a general midtone drift as you might expect.
Back to the baseline image.
WonderPana ND4 2-Stop Neutral Density Filter, unadjusted
WonderPana ND4 2-Stop Neutral Density Filter, adjusted
To bring the 2-stop ND back in line with the baseline image required just +1.07 exposure adjustment, not 2 stops.
WonderPana ND32 4-Stop Neutral Density Filter
By the time we get to the 4-stop ND there is a very noticeable color cast. Correcting out magenta can sometimes be quite a pain compared to, say, a blue shift. If one has to deal with a color, pray it's of the blue variety. Other color shifts, like bronze and magenta, can lead to hours in post, fiddling with sliders and pulling hair.
WonderPana ND4, adjusted
You can see the red channel breaking away from the rest in the ND32's histogram. For its part, the ND4 holds up well where this is concerned. The adjusted ND4 image is a good facsimile of the baseline image, if only slightly more red. Then again, it's not a significant deviation, requiring only +1.07 stops to compensate for.
Thinking back on the reflected color change of the physical filters themselves, going from bronze to green, perhaps whatever change to the formula that is used to create the stronger density resulting in the green reflection is the culprit in the drastically more reddish example image. Who knows but the wizards concocting the density formulas.
Baseline Corner 100%
WonderPana ND4 Corner 100%
Here again the sharpness seems nearly unaffected. Contrast is subtly affected and now there's a visitor on the flamingo, but apart from that there is little different between the two images. The slight red that was hinted at in the histogram can best be seen in the brickwork here.
Back to the baseline...
WonderPana 2-Stop Soft Graduated Neutral Density
WonderPana 2-Stop Soft Graduated Neutral Density
After the predictable midtone drift, the WonderPana 2-stop soft grad does well with color. Again, we have a slight reddening of the affected area, which is now the upper half of the image.
Baseline Corner 100%
WonderPana 2-Stop Soft Graduated Neutral Density Corner 100%
This close-up of the corner is really only a test of the quality of the resin used in the WonderPana system. As mentioned earlier, this area, and indeed all the corners, represent where the filter is at its thickest with regards to light travel. The CR-39 shows how little quality resin affects the resolution of an image even at 4mm thick! That impresses me.
After having used just about every piece currently available in the WonderPana 66 system, I feel the quality is overall better than I expected. I was, however, disappointed with the fiddly nature of the optional bracket, but considering the all-aluminum design I'm not sure there is a practical alternative that keeps the design tool-less, which I'm sure was a major goal of the Fotodiox engineers. The color cast of the amittedly low intensity ND filters is not without precedent, even by filters from highly reputed manufacturers, like Formatt-Hitech and Cokin, but it's unfortunate that the cast wasn't blue. At least it's not bronze. /shudder
Also, I would have liked to see a more convenient way to rotate the rectangular filter rails for scenes where you'd like the transition line for the grad filters to be at an angle. A clip-on rail bracket, similar to what's employed by the Lee Filters Foundation Kit would have been preferred. This design change might also alleviate the need for the user to juggle two different length thumbscrews. This, of course, could have made the bracket more cumbersome in packing and carrying, but the trade-offs, at least on the face of it, seem to be worth it. Unlimited angle choices isn't a minor thing. For some, though, angle options at 45° intervals might be just fine.
Attached to the lens, the system seems bulletproof. It's going to last quite a while if you take care of it, so as a long term investment the WonderPana should satisfy there. And since Fotodiox include high quality pouches for all the pieces, protecting the components shouldn't be a problem.
Best of all, the system is nearly complete. Hitech's LucrOit system may have more slide-in options, like alternate colors or the very popular reverse grad ND, but LucrOit doesn't have a convenient polarizer, nor can you use screw-ins, which don't have a habit of falling off when you're moving about. Were Fotodiox to come out with a reverse grad and a 10-stop ND there wouldn't be much reason you'd ever have to leave the WonderPana system.
Speaking of completeness, Fotodiox now make a series of step-up rings that allow you to attach the 145mm screw-in filters onto conventionally threaded lenses. It's possible that you could take to the field and only have to carry one set of filters! You cannot, at this time, connect the Optional Bracket for the slide-in rectangular filters to the step-up rings, however. (This would be another limitation that could potentially be avoided with the aforementioned clip-on style bracket design.)
The Fotodiox WonderPana 66 system cures just about everything that ails the ultra-wide angle landscape photographer.
EDIT (9/24/13): Fotodiox have upgraded the WonderPana Core so that it now allows the Upgrade Bracket to rotate. You can now set the graduated NDs at any angle you need. That's great! The new Core Unit is now branded FreeArc, but is currently only available for the Nikon 14-24mm. Hopefully, Fotodiox won't waste time getting FreeArc support for the other UWA lenses like the ubiquitous Samyang 14mm.
They say to err is human. In that case, photography often reminds us how human we are. The process leading up to the point where you press the shutter release is frought with opportunity for oversight and mistake. Others may not appreciate it, seeing only the final image, but to get to that point a photographer usually has to be mindful of many things and juggle them all successfully - aperture, shutter speed, ISO, composition, right down to making sure the battery has enough charge or that there's enough space on the memory card.
What follows are oversights on my part that I feel are not common things photographers think about but can surely foul a picture up if not corrected.
Turn Off Image Stabilization When Using A Tripod
This almost seems counter-intuitive. After all, a tripod, like optical vibration correction, is meant to stabilize the camera, too. Shouldn't those two things working together make the camera more stable than either by itself?
The Canon 70-200mm f2.8L II attempts to correct for movement that isn't there.
When the camera engages the image stabilization motors it cause the image to jump, if for a brief moment. Left engaged, the image stabilization system often times will jump randomly as it attempts to correct for movement it thinks should be happening. Some newer lenses employ tripod sensing algorithms that shut down the stabilization motors when the lens detects no movement, assuming that the camera must be on a tripod. However, best practice is to just turn the image stabilization off when the camera is tripod mounted to avoid any shot killing hiccups.
Detail of above.
If you've ever used a tripod and inexplicably ended up with an image that isn't as sharp as you think it should be, check that the image stabilization is turned off.
Be Careful When Using Polarizers On Ultra-Wide Images
Perhaps the single most important filter in any photographer's bag is a quality circular polarizer. I use Singh-Ray, B+W, and Lee for the different polarizers I like to use - warming, multi-coated, and 4x4 square, respectively. In my opinion, these filters are the pinnacle of performance and quality. However, like all circular polarizers they are at the mercy of physics. Polarizers work best when the sun is at 90 degrees from the subject, that is if you point at the subject with your index finger ideally you want your extended thumb to be pointing at the sun. This limitation means that for wide angle lenses, or any lens wider than 28mm, only part of the image can be polarized at a time.
Notice the polarization artifacts, the rings on the right of the image.
This effect can become even more pronounced if you take a long exposure with a moving sky, as above. This particular artifact could not be seen in the viewfinder, but the dark banding could. (The "dark banding" refers to the darkened of part of the sky, the part that is actively being filtered by the polarizer.) However, as the clouds moved at the extreme edge of the image it became possible to see the polarizer's foil structure. Do you notice the concentric circles most evident on the right side of the image? This artifact can be a real bear to correct in Photoshop!
Micro Focus Adjust Your Lenses or Have Them Professionally Calibrated
If your camera is from within the last 6 years or so and is above consumer grade chances are it has the ability to individually adjust the focus of your lenses. This is especially critical for lenses with large maximum apertures since if the focus is off by even a little it can dramatically alter the shallow plane of focus, and thus the sharpness of your subject.
Portrait taken with a back-focusing lens.
The above was shot with a Canon EF 85mm f1.8 at f2.5. This means that I was working with a very narrow depth of field. As is standard when taking portraits, focus was placed on the nearest eye but if you look closely, you may notice that it's the farthest eye that is more sharp.
Detail of above.
Looking at the above image on the back of the camera, without zooming (also a no-no for checking critical focus - always zoom into an image!), you may not notice that focus was missed. In fact, this image was meant for web-sized display on a company's internet site, so anyone would be hard pressed to see that the left eye isn't tack sharp.
But, what if this were meant for print? What if it was going up on the company's lobby wall? Suddenly, it's not good enough and should be considered a missed or wasted shot.
It turns out the lens was indeed back focusing. Back focusing is when the lens is returning a positive focus lock at a point when in fact the lens is optically focused behind that point, or farther from the viewer. (Front focusing is the opposite.) Using a LensAlign Pro I determined that the lens needed -18 adjustment on my Canon 5D Mark III camera. (This number is arbitrary and would differ from camera model to camera model and certainly maker to maker.) A correction that great is something more than I care to correct for in camera (most corrections are within the single digits) and this lens will be sent to Canon for some permanent adjustment.
Hopefully this will give you, faithful reader, some food for thought and perhaps you'll have more keepers for it.
It's a phrase we, as the de facto family photographer, say to children until we are blue in the face. Sometimes it even works. The problem is we aren't that interesting to the child. Afterall, they see us all the time. Usually, if they look at us at all it's for a split second, usually when their parents aren't, and then it's gone in a flash (literally).
I'm constantly asked to do portaits of the rugrats in our family and, though I enjoy the results, I cringe at the thought of uncooperative tikes.
I came across a product, the maker of which I can't remember, that suspended a smartphone beside the lens of a camera. The smartphone would be put on autopilot, displaying a light show in attempt to attract the attention of wandering eyes. "Brilliant," I thought, "This will solve everything!" (A phrase uttered by me, upon seeing some new gadget or piece of gear, at least twice a week.)
I knew I had laying around enough hardware (as the result of many other such epiphanies, as stated earlier) that I could cobble together something similar.
This is what I came up with:
Frankenstein Attention Rig
I took a Wimberley F-2 Macro Flash Bracket, attached it to the Really Right Stuff L-plate on my camera, and screwed an eBay tablet mount (similar to this one) at the end. In the clamp I put my Samsung Galaxy Tab 2 7" tablet and set it to run the Party Light app, which is also available as an ad-supported free download.
Considering the build and weight of the Wimberley bracket I would trust that arm with a full-sized 10" tablet as well. You can also use a smartphone, but obviously the screen will be quite small when viewed from several feet away.
The weight of the entire rig isn't anything to sneeze at. My arms got tired after a 15 minute session.
Canon 5D Mark III with Sigma 50mm f1.4 EX HSM at f2, 1/200 sec., ISO 800
Now I need to figure out a way to get them to smile...
Coming over from the iPad I was familiar with the apps designed to aid photographers on iOS. Google's platform, however, was a little different because some apps didn't have Android versions and what was available many times did not have long review histories. Choosing Android apps was hit or miss and often left you checking to see if you were still within the refund window.
These days the Google Play market is much more mature and it's easier to find something worth downloading. The quantity of quality Android photography apps is easily on par with what's available on iOS, and in some cases, like those apps which can directly control your camera, quite a bit superior.
Here is a list of Android apps worth your dollar(s):
The Photographer's Ephemeris
This is the cat-daddy landscaper photography app. The Photographer's Ephemeris let's you plan a shot by showing how light will fall on a scene at a given time. If you want to know where and when to stand to be best positioned for sunrise this is the app to check. It integrates Google Maps and uses GPS for accuracy. There is no better map-centric sun and moon calculator currently on the market.
This app may be most responsible for Canon users choosing the Android platform to begin with. DSLR Controller directly controls your Canon camera, allowing you to view Live View on your 10" screen (or 4.5" smartphone screen, whichever floats your boat).
You have control over shutter speed, aperture, ISO, focus, etc., from your Android device. This is great for when the camera is positioned in such a way that makes it difficult to see the viewfinder or the screen. There are even intervalometer and bracketing controls!
See the program link for a full list of impressive features.
Tip: If you are having connectivity issues a common cause is the On The Go USB cable. There are many cheap OTG cables that cause communication errors and freezing. Try a different USB host cable. Also, check the developer's website for compatability with your hardware.
There are now similar apps that also support Nikon cameras, like the very popular Helicon Remote, so don't fret if you shoot on that platform.
Photo Mate Professional
Photo Mate Professional is an image viewer and editor that lets you work with RAW files, be they CR2 (Canon) or NEF (Nikon). You can even use Photo Mate to calibrate your tablet's display or run a portfolio slideshow.
Apps like this are essential to the mobile workflow. There aren't many editors on the market that let you work in RAW and we're lucky there is a very good one in Photo Mate available. It's a little pricey for an app, with cheaper versions you can choose that omit features like image editing, but the Professional version is worth the money.
Android Photo Review
If you are looking for something light that can help with culling images after a shoot Android Photo Review might be all that you need. It's a simple browser that is compatible with most RAW formats. Android Photo Review let's you browse your compact flash card and star images for future editing. You can even view histogram information to aid with rating images.
As with the entire Asus Transformer line, my Transformer Prime has access to the Transformer dock which adds a full sized USB port (among other useful things). I attach a USB card reader, insert my compact flash card, launch Android Photo Review and browse the images on a large 10" screen without having to waste time transferring images to the tablet - Try that, iPad users. When I'm done I can put the card back into my camera and the ratings are preserved within the images.
With the release of the 5D Mark III Canon added a feature that was previously only available in the flagship 1D lines - dual card slots. One slot is compact flash and the other SD. The latter is important in that it gives you native access to Eye-Fi's clever wi-fi SD cards. (The Canon 5D is even one of the first cameras to be "Eye-Fi certified." When an Eye-Fi card is inserted and detected a menu option becomes available, giving you some control over the card.)
When setup, you can wirelessly connect your camera to the tablet and watch the images pop up on the screen as you take them. This is perfect for model shoots or any shoot where you want to instantly review the images without relying on the camera's 3" LCD screen to do your chimping.
I set the Canon 5D Mark III to send full sized RAW images to the compact flash and S2 JPEGs (one notch above the smallest file size possible) to the SD card. S2 gives adequate resolution for checking focus yet keeps the files size small enough that sending the pics wirelessly doesn't slow the process down to a crawl. It's the preferred quality/speed compromise.
One more tip for Canon 5D Mark III shooters: Put "Record func+card/folder sel" in your My Menu for quick control over the two cards. This will let you choose which card to read/write to and browse. Remember, when you format one card you have to manually switch to the other card to format it as well. If you shoot video, double check that the CF card is set to primary. Diligent management of the two cards will mean you only have to import one of them at the end of the day.
Photo Tools Pro
There are many apps that offer calculators beneficial to photographers, like DOF and exposure calculators, but Photo Tools Pro includes the most. They are also quality calculators. For instance, the exposure calculator figures out shutter reciprocation which is very handy for those long 10-stop exposures.
In one app you have fingertip access to an FOV calculator, flash exposure compensation calc, rudimentary light meter, gray card, time lapse calculator, timer, stopwatch, moon phase calc, weather forecast, color wheel and temperature charts, sharpening radius estimator, note pad, and even a gallery for inspiration, to name a few.
Photo Tools Pro is at home on both your tablet and smartphone. There is an ad-supported free version available, but consider the donation version to better support the developer.
Geotag Photos Pro
For those who don't have geotagging accessories, like the $250 Canon GP-E2, but do have a smartphone, Geotag Photos Pro lets you geotag your images without the hassle of managing more gear.
Launch the program, set the update interval (I usually set it to update every 5-15 minutes) and put the phone back in your pocket. When you're done, stop the logging to conserve battery power. When home, browse to the Geotag Photos site to merge the GPS log data with your photos. Lightroom and Aperture will now plot the images on a map.
Tip: Android phones are notorious for zapping battery life. Running power intensive apps in the background, like Geotag Photos Pro, exacerbate the problem. To ensure that you have adequate juice consider packing an extra power source. I recommend the Sanyo Eneloop Mobile Booster. (I have the KBC-L2B version) It's 5000mAh of extremely portable trip saving power from one of rechargeable battery's most revered brands. You'll probably have to import it from Korea as it is no longer available for sale in America, though eBay has many Korean sellers who export and include the proper North American power plug adapter. It has enough to recharge both your phone AND tablet on one charge.
Posing App is a great collection of 244 poses to help inspire you and your model. You don't realize how difficult it is to come up with complimentary poses until you try. When time is critical (when isn't it?) it helps to have examples to instruct a subject.
There are several posing image collections available but I think Posing App has the deepest and varied collection of quality poses. There are even tips with each pose to help with model instruction. Your mileage may vary but it's worth a look. For a few dollars more you can unlock the glamour set which adds 56 "glamour" poses.
Here is a list of some other apps you may want to investigate.
Easy Release - Model Releases - Be aware that there is a lot of controversy regarding the legal value of digital model releases. Physical signatures are the most safe, but digital releases are far better than nothing.
Remote Release - Trip your shutter with your phone tethered with the same OTG cable you use for DSLR Controller.
Android Photo Backup - Backup your images to your tablet or smartphone. With the proliferation of expandable memory on Android devices why not ditch your portable hard drive and use your tablet? That would be one less thing to carry, and viewing images on a 10" screen beats the bejeezus out of viewing them on your 3" HyperDrive Colorspace.
Lighting Studio - Record your lighting setups for quick and accurate recreations.
Instagram - For when you don't want to work at it.