Photos are meant to be viewed large. Yet when taking a shot--that crucial moment when we should be most discerning--we usually rely on the camera's small LCD to preview the image. The traditional solution has been to "tether" the camera to a computer, so you can view shots on a large screen as they're captured, or even control the camera's settings and trigger the shutter remotely. That approach lets you correct the scene or settings and reshoot immediately if anything looks amiss.
But tethering can be limiting. Setting up a laptop on location is often inconvenient--and even if you're shooting in a studio, tethering typically involves snaking a USB cable between the camera and the computer.
A few new camera accessories aim to redefine tethering. The CameraMator, the CamRanger, and the iUSBportCamera communicate wirelessly between a camera and an iOS device, enabling you to control (on most DSLRs) such shooting settings as aperture, shutter speed, ISO, and white balance, and transfer the resulting photos for review, taking advantage of the iPad's large screen. Even the iPad mini, iPhone, and iPod touch offer a better view than the camera's LCD does.
Since these devices operate wirelessly, you can use the iPad anywhere within Wi-Fi range. Each accessory can create its own Wi-Fi network, so you don't need to rely on existing infrastructure. Wireless control allows hands-free shooting in situations where the camera needs to be locked down on a tripod--for example, when you're photographing products. Alternatively, you can hand an iPad to clients who are present during a photo shoot so they can review photos without hovering over your shoulder.
Keep in mind that support for specific features varies depending on camera model, and that only DSLRs made by Canon and Nikon are covered at all. Video recording, for instance, doesn't work with my aging but still popular Nikon D90. So be sure to check the camera compatibility of each device's at its manufacturer's website. Prerelease software for OS X, Microsoft Windows, or Android is available for download.
Wooblue's CameraMator ($299) attaches to a camera's hot shoe and connects via USB. The hot shoe is just one convenient mount point, however--the CameraMator also includes a thread for attaching to a light stand or tripod. Like the other two devices reviewed here, the CameraMator runs on a rechargeable battery.
To use the CameraMator, you need the CameraMator iOS app which costs a surprisingly steep $25 (the apps for the other devices are free). The Mac app costs $30. Since the hardware is useless without the app, the pricing of the two seems disingenuous.
Turning the CameraMator on creates an ad hoc Wi-Fi network, which you connect to in the iPad's Wi-Fi settings. In the CameraMator app, you have the option of setting up the device to connect to an existing Wi-Fi network instead of creating its own. Once you've set up the network, you choose one of two modes: Remote Camera lets you control the camera, and Session Preview displays photos captured by the camera--but without any remote-control capability.
CameraMator covers the shooting basics: You can set aperture, shutter speed, ISO, and white balance using popovers. When you tap the shutter button, the camera captures a shot, which appears in the app after a few seconds. A Live View mode lifts the DSLR's mirror and lets you see what the camera sees, albeit in a low-resolution, low frames-per-second preview.
Much of the functionality depends on the camera's settings. You set the shooting mode (Program, Aperture Priority, Shutter Priority, Manual, or a scene preset), as well as preferences for auto-focus, metering, and exposure compensation, on the DSLR. The CameraMator requires you to shoot in JPEG or Raw+JPEG format; it can't work with straight Raw files.
Beyond the basics, the CameraMator app offers a Self-Timer mode for configuring how many frames (up to 8) to capture at a set interval (between 10 and 30 seconds), a Duration control for specifying a total length of shooting time and the interval between shots, and an HDR mode for capturing 3 to 5 frames at different exposures to create High Dynamic Range images. The Duration control is especially useful for assembling a series of time-lapse photos over several hours.
Hyper's iUSBportCamera ($300) resembles the CameraMator in external design, and the two devices' hardware is exactly the same. (Hyper originally distributed the CameraMator.)
The difference, of course, is in the software. The free iUSBport app for iOS offers the same features found in the CameraMator app, with a few additional capabilities.
In Live view, tapping an area of the screen prompts the camera to focus there. The iUSBportCamera also lets you connect two iPads in client mode, thereby preventing embarrassing skirmishes among your clients over who gets to hold the iPad. Raw images aren't a problem--the app displays the JPEG preview created by the camera. And Hyper incorporated its other iUSBport device's capability to stream media from a USB-connected flash drive or bus-powered USB hard drive to the iPad. When you're not processing your photos, you can watch movies or listen to music without storing them on the iPad itself.
Of the three models I examined, the CamRanger ($300) has the greatest number of features for controlling the camera. The free CamRanger app handles various controls and lets you choose the image format (Raw, JPEG, or Raw+JPEG, including different JPEG image sizes), exposure compensation, and metering mode. For models that support it, CamRanger can put the camera into PC mode, giving you control over the shooting mode.
A Focus Stacking feature captures several photos at slightly different settings to help you get tack-sharp focus, such as when you're shooting macro photos with an extremely shallow depth of field. If you're shooting time-lapse photos using the intervalometer feature, the iOS device doesn't have to remain connected to the CamRanger; once begun, it operates independently.
The CamRanger is also unusually helpful while shooting, with optional overlays such as highlight and shadow warnings to give you a better idea of whether dark or light values are getting clipped due to the exposure.
My only complaint about the CamRanger is that it can't hop onto an existing wireless network. Instead, you must initiate an ad hoc connection to the Wi-Fi network it creates. If you need to switch to a different app on the iPad to look something up on the Web, for example, you must switch networks. (Cellular-capable iOS devices can still access the Internet.)
The CamRanger is not designed as a camera accessory (the hardware is actually a wireless router by TP-Link). Unlike the two other devices, which fit into the hot shoe on top of the camera, the CamRanger is a freestanding slim box connected to the camera via USB. Unfortunately, its odd shape makes positioning it awkward. An included neoprene pouch lets you connect it to the camera strap or to a tripod, which helps but isn't elegant. (If you needed to use the hot shoe to accommodate a flash or a trigger, of course, you'd have to find a new location for the CameraMator or iUSBportCamera.)
Seeing the big picture
If you're looking for an inexpensive way to transfer photos wirelessly from a camera to an iOS device or computer, a Wi-Fienabled SD card like the Eye-Fi or the Toshiba Flash Air should work fine. But if you often shoot in a studio or in situations where you need to lock your camera in place and control it remotely, these wireless tethering accessories are compelling.