|A preview of the Nikon D2H - Continued|
This section examines the D2H's balance of speed and accuracy in several core areas, including frame rate, autofocus and flash.
Frame rate, shutter lag and burst depth
By adjusting the camera's startup sequence and delaying certain system checks, the camera will fire almost immediately after it's turned on. The D1H, by comparison, takes about 4/10 second before it's ready for action, and longer still with certain CompactFlash cards.
Once the D2H is switched on the fun really begins. Nikon is promising 8 fps, regardless of ISO, file format or AF mode. The camera's Continuous High setting is fixed at 8 fps; Continuous Low is adjustable from 1-7 fps in 1 fps increments. The shutter in prototype models certainly trips by faster, and also sounds smoother, than the D1H. Other basic speed-enhancing features include:
- A shutter lag of 37ms. If this pans out, the D2H will have the shortest shutter lag of any currently-shipping autofocus film or digital SLR we know of. This would compare to, in our testing with a PocketWizard MultiMAX, 45ms for the Nikon F5, 56ms for the Canon EOS-1D and about 70-80ms for the D1X and D1H (we've never tested a D1X or D1H that delivered Nikon's spec of 58ms). In addition to a shutter lag promised to be ultra-short, the noticeable fluctuation in lag time of the D1-series cameras (even when shooting without AF, TTL flash or other shutter lag-varying factors) is also promised to be absent from the D2H. For serious remote use, a stable lag time for synching with other cameras and strobes is a must; D1H and D1X users either had to install a third party lag correction circuit or live with slowish sync speeds (which allow for a bit more shutter lag mush).
Update: Several readers have correctly pointed out that the Contax RTS III's shutter lag spec is a sprightly 21.8ms. If this is measured in a manner comparable to the testing we describe above, then this manual focus camera might well grab top honours for having the shortest shutter lag of any SLR camera currently on the market. In addition, the discontinued Canon EOS-1N RS sports a lag time of 6ms, thanks to its fixed-mirror design.
- A shutter lag time that's trimmed dramatically, from 37ms to 2ms (yes, 2ms) when the D2H's new mirror lockup function is engaged. Unfortunately, the mirror can only be locked up for a single frame at a time, which will make it all but impossible to take advantage of this incredibly short lag in remote shooting applications.
- A mirror blackout time of 80ms. Assuming there's a standard method for measuring this, then this would compare favourably to the 87ms mirror blackout time of the EOS-1D. If you've shot extended sequences with a 1D and a D1H, you know that it's somewhat easier to keep things framed up with the 1D. That's because the mirror travel through the viewfinder is less noticeable with the 1D, and therefore doesn't interfere as much with visual tracking of a moving subject, like a scrambling quarterback. We haven't been able to unearth the mirror blackout time spec for the D1H, but it's almost certainly much longer than the 80ms quoted for the D2H. Nikon indicates that the mirror blackout time of the D2H is simply the shortest in its class. An illustration of the D2H's mirror balancer is shown at right.
- A 150,000+ cycle shutter, made from an aluminum alloy called duralumin, which controls the exposure time. This is a departure from the D1-series cameras, all of which utilize a simple shutter whose primary purpose during the exposure is to get the heck out of the way. That's because, in the D1, D1X and D1H, the on/off cycle of the CCD is adjusted to provide the shutter speed selected. Not so in the D2H, which returns to a more traditional method of exposure time control in which the open/close cycle of the shutter is once again the shutter speed. This also means that the top shutter speed is 1/8000, down from 1/16,000 in the D1-series cameras. Flash sync is discussed in the flash section ahead.
- A cavernous memory buffer means that, despite the larger file size of the D2H relative to its predecessor, it still offers a burst depth of 40 JPEG frames. This number drops to 35 for TIFF and a still-plentiful 25 for RAW NEF. It's possible - though Nikon has not confirmed this - that the burst depth specs are minimums, as the prototype model we handled showed itself to be capable of shooting 50 JPEGs in a burst. Whether it's 40 frames or 50, the D2H - like the D1H before it - will be one of the few digital SLR cameras that doesn't require the user to be ever-mindful of hitting the buffer limit in sequence shooting, even when set to fire at 8 fps.
- A quirk of the D100 seems to have found its way into the D2H, at least at this stage in the D2H firmware's development. Switching on long exposure noise reduction in Custom Settings immediately drops the burst depth shown in the frames remaining counter. For example, with the camera set to NEF, the number of possible frames drops from 25 to 15. This is true even when the shutter speed is well above the long exposure noise reduction threshold. Unlike the D100, however, the D2H seems to mostly or entirely ignore its own frames remaining counter when long exposure noise reduction is switched on and the shutter speed is brief. All of this could be early firmware shenanigans, we're not sure.
- The D2H prototype we tried would write out all pictures to the card even if the camera's power switch was turned off (yeah!). By comparison, D1-series cameras will finish writing only the current file and flush the rest. Also, when the buffer fills, simply keeping the shutter button mashed down will mean the D2H will fire again as soon it's able. D1-series cameras require that you first take the pressure off the shutter button, pause long enough for the buffer to be cleared of at least one frame, then squeeze it down again.
Nikon D2H - AF area grid
The first all-new, top-end Nikon autofocus system since the F5 has been designed for the D2H. Called the Multi-CAM2000, it features 11 AF areas arranged in what Nikon refers to as a "rule of thirds" grid. The AF areas cover about 75% of the frame horizontally and about 44% vertically.
The most significant achievement in the Multi-CAM2000 is that 9 of the 11 AF sensors are cross-type (all but the outermost two horizontal sensors). Cross-type sensors are better at detecting the contrast an AF system needs to establish focus, especially in low light. In practice, cross-type sensors simply mean better AF performance under a variety of conditions.
At 9, the D2H has 6 more cross-type sensors than the D1H, and 2 more than Canon cameras utilizing the company's 45 point AF system, including the EOS-1D. The 9 are arranged in what is a broader and probably more useful pattern than Canon's system too, and all 9 sensors continue to operate as cross-type even with lenses whose maximum aperture is f/5.6. In short, 9 cross-type sensors, covering such a wide area, should be fantastic.
A new, 8-position multiselector enables up/down as well as diagonal movement through the 11 AF areas.
The D2H offers four AF area modes: Single Area AF, Dynamic AF with Focus Tracking and Lock-on, Closest Subject Priority Dynamic AF and Group Dynamic AF. Group Dynamic AF is new in the D2H, and allows for the selection of up to 11 different AF area groups, in two different patterns of either 3 or 5 AF areas. This should allow plenty of flexibility in the use of this function.
In addition, Nikon promises quicker acquisition of focus when the lens' focus point and where the focus needs to be are far apart. With any AF system, there is a point at which the lens image is so out of focus that the system has to begin scanning through the entire focus range of the lens before it can detect a focus point. Nikon claims the defocus limit for the D2H is 2 times greater than other unspecified cameras (which almost certainly means models from Canon).
The D1H and the EOS-1D have been our primary sports cameras over the past couple of seasons. In using both systems, we've learned a few things about each:
- For tracking a moving subject with a single focus point, both Canon and Nikon's digital action cameras do a superb job. We've been especially happy with the D1H in this regard.
- There is a noticeable drop in the number of in-focus frames when either camera is set to automatically select the focus point. With the EOS-1D, regardless of the AF pattern chosen, it seems that the extra calculating it has to do in choosing the focus point puts a drag on overall performance. With the D1H, Dynamic AF has a tendency to shift to the background when the action stops at the end of play, even if Closest Subject Priority is enabled, while the spacing of the 5 AF points across the frame means that unless the action is tight it's possible to have the subject slip between the AF marks just long enough to confuse Dynamic AF.
- With lenses longer than 300mm, the EOS-1D is able to acquire the focus on the first frame much faster than the D1H. The D1H (as well as the D1X and original D1) imposes a noticeable pause before snapping into focus when shifting from the quarterback to the receiver with the 400mm and 500mm lenses we've used over the last couple of football seasons. This hasn't stopped us from shooting football with the Nikkor AF-S 500mm f/4D IF-ED II, but it has meant a change in shooting technique to try and compensate for the pause.
Since the F5, Nikon has had an AF system that tracks moving subjects really well, especially in Single Area AF mode. We hope that the 11 AF areas of the D2H, coupled with their Group Dynamic AF configurability, make Nikon's Dynamic AF usable in a wider variety of shooting situations than it is today with the D1H. Most importantly, we hope that the the sum of what's gone into designing the Multi-CAM2000 is a reduction in the AF pause that limits the usefulness of the D1-series cameras for shooting herky-jerky, long lens action.
When the D2H is paired with one or more Speedlight SB-800 strobes, the changes in the Nikon flash system are all great news. From full-featured wireless triggering to TTL above the camera's standard top sync speed of 1/250 (courtesy of the SB-800's Auto FP High-Speed Sync mode), the SB-800 and D2H should turn out to be a powerful combination if the new features work as promised.
A separate article discusses the SB-800. Here, we'll run down some of the D2H's basic flash features, and flash differences, relative to the D1H.
Hidden High-Speed Sync No More: One of the benefits of the Interline Transfer CCD used in D1-series cameras is its ability to control exposure time electronically within the sensor. This enables a 1/16,000 top shutter speed, 1/500 standard top sync speed and, most importantly to us, the D1/X/H's ability to sync with non-dedicated strobes at shutter speeds that are positively stratospheric.
The combination of the CCD and shutter design means that synching with catwalk-mounted, radio remote-triggered lights at shutter speeds of up to about 1/1250, instead of at or below the standard top sync speed, became possible. Or, shooting outdoor portraits with big lights, but shooting at a small aperture and ultra-brief shutter speed for shallow depth of field. This is a way cool unadvertised feature of the D1-series cameras (and the EOS-1D, which uses the same type of sensor).
The LBCAST sensor in the D2H doesn't control the exposure time internally, instead relying on the shutter to do that. That brings an end to the high-speed sync trick we just described. We suspect it will be possible to cheat the shutter speed up to perhaps as high as 1/400 with non-dedicated strobes, as it has been with virtually all other digital SLR cameras with similar-size sensors. And the SB-800's Auto FP High-Speed Sync mode will help ease the transition. But, the fact remains that one of the niftiest flash capabilities of D1-series cameras is absent in the D2H.
Other D2H flash facts include:
- The D2H offers Nikon's usual complement of flash modes, including red-eye reduction, rear curtain sync and slow sync. One welcome change: the shutter speed floor for slow sync is now choosable in a Custom Setting; previously, you either lived with the hard-wired floor of 1/60 of the standard sync mode, or switched to slow sync and let the shutter drag for as long as the meter thought it ought to (when shooting in Aperture Priority, for example). With the D2H, it's possible to put the brakes on at 1/4 second, or 1/2 second, or another shutter speed of your choosing. This should make slow sync a lot more useful.
- Like all other Nikon digital SLRs, the D2H's calculation of the TTL flash output occurs before the photo is taken, by measuring the Monitor Pre-Flash bursts. This means that in most or all flash modes, the Speedlight SB-800 will fire twice: once prior to the shutter's opening, from which the flash exposure is calculated, and again during the actual exposure. This behaviour isn't new to Nikon digital, and means that there is no real-time calculation of flash output off the film plane during the actual exposure, as there is with comparable Nikon film cameras. This isn't necessarily a problem, especially if the considerable effort Nikon has put into the D2H/SB-800 combo translates into best-of-class TTL flash output. If that's the case, then it doesn't much matter when the calculation is taking place.
- Except for rear-curtain sync photography! With the D1H and SB-80DX set to 3D Multi-Sensor Balanced Fill-Flash, the flash calculation occurs just prior to the beginning of the exposure, but the flash fires at the end of the exposure, during which time it's possible for the subject to have moved considerably closer to or further away from the flash. The result, as one might expect, is a bad TTL flash exposure. The D1H rear-curtain sync solution has been AA (Auto Aperture) mode on the SB-80DX, which does calculate the flash exposure in real-time (Monitor Pre-Flash is disabled in the SB-80DX's AA mode), through a sensor on the Speedlight itself. What's new, at least when the SB-800 is paired to the D2H, is that the Monitor Pre-Flash fires even when Speedlight is set to AA (Auto Aperture) mode. We haven't been able to determine whether the AA flash exposure is calculated from the Monitor Pre-Flash or the actual flash. If it's from the Monitor Pre-Flash now, then we hope Nikon has devised some other way of making properly-exposed rear-curtain sync photos. Also, the firing of Monitor Pre-Flash in AA mode will mean that only the M (Manual) mode will be usable for triggering old-fashioned optical slaves connected to other flashes in the scene, since these slaves will trip when the Monitor Pre-Flash fires. Clearly, Monitor Pre-Flash's role in SB-800 modes other than TTL is going to take some figuring out.
- Flash Value Lock (FV-Lock) locks the flash exposure for one or more SB-800's, even if you recompose or move. When working a fixed distance from a subject and shooting a sequence of photos, this should be a handy way to keep the flash output absolutely consistent from frame to frame. FV-Lock is engaged by pressing the programmable FUNC button on the front of the camera.
- The 5-segment TTL Multi Sensor in the D2H is not the same as that found in the D1X and D1H; Nikon claims improved exposure accuracy and consistency from the revamped component (and the algorithm that drives it), with the SB-800 certainly, and we presume the SB-80DX, SB-50DX and SB-28DX as well. In addition, when the SB-800 is connected to the D2H and set to i-TTL, the flash exposure is calculated from both the 5-segment TTL Multi Sensor and the 1005 pixel metering sensor (which, in previous cameras, has handled only ambient exposure measurement). When SB-800's are used in an i-TTL multiple flash arrangement, the flash exposure is calculated from 1005 pixel metering sensor data only. In short, TTL in the D2H, when the Speedlight is the SB-800, represents a significant departure from previous Nikon film and digital SLR models.
- The flash exposure compensation value set on the flash is not recorded into the EXIF metadata of the picture file. This is a key piece of shooting information to refer to when learning a flash system, and we're puzzled that in designing the D2H and SB-800 that this hole in the EXIF data wasn't filled. Of Nikon's range of digital SLR models past and present, only the D100 records this info into the picture file, and then only when its pop-up flash is used. UPDATE: Files from later preproduction D2H cameras now do contain flash exposure compensation data from both the SB-800 and SB-80DX Speedlights (and probably other Nikon flashes too), in either TTL or AA modes. Near-final releases of both Nikon View 6.1 and Capture 4 show this info.
- Wireless TTL, wireless transmitting - very, very cool. We would have been even more impressed if Nikon had announced a wireless hat trick by also incorporating PocketWizard long-range wireless camera and strobe triggering right into the camera. A third-party add-in module is already available for the D1, D1X and D1H that does this. We had hoped that the next generation of Nikon pro digital would fully embrace the PocketWizard way and build complete and easy-to-use support directly into the camera.
The battery system in the D2H is completely revamped. The battery is smaller and lighter than that of the D1H and utilitizes Lithium-Ion (Li-Ion) instead of NiMH. The camera itself incorporates the first attempt we've seen by a camera manufacturer to provide truly precise, accurate indications of both a battery's charge status as well as its service life. Key battery system features include:
- The EN-EL4 battery is a removable, rechargeable 11.1V/1900mAH Li-Ion pack. At 11.1V, the EN-EL4 has a considerably higher voltage rating than the D1H's EN-4 at 7.2V. The higher voltage of the EN-EL4 was needed, in part, to drive the mechanical components of the D2H at their 8 fps operating rate. The EN-EL4, which is somewhat squarer and shorter than the EN-4, weighs in at 180g (6.3 oz). It does not include a charge status indicator on the battery itself.
- The battery end cap clips onto the EN-EL4; a small switch on the cap facilitates its removal. Though the camera will ship in most or all regions worldwide with one EN-EL4/end cap combo, additional batteries and end caps will be sold separate from each other. It will be possible, then, to stock your camera bag with more batteries than end caps to save space, at the cost of having to swap end caps when replacing the battery in the camera. In addition, Nikon will be making available two different end caps: the standard end cap, plus a second one that includes a lug that snugs the WT-1 transmitter cable close to the camera body.
- The combed, inset connectors on the EN-EL4 should make it difficult to short out the battery against metal objects floating around in your camera bag.
- Nikon has not released a frames-per-charge specification.
- The EN-EL4 is recharged by the single-slot Quick Charger MH-21. A full charge takes about 100 minutes. No dual-slot charger will be made available at the time of the D2H's release, and Nikon has not indicated if one is in development.
- The D2H shows EN-EL4 battery status in three locations. Inside the viewfinder is a 5-segment charge life indicator; a similar indicator is repeated on the top LCD display. Among the camera's extensive menus is a battery status screen that shows charge remaining in 5% increments, the number of frames remaining, a 5-increment battery service life indicator (so you know when it's time to retire the battery altogether) and a flag indicating whether the battery should be "calibrated," a procedure performed by the MH-21 that allows for the D2H's battery status screen to report accurate information.
The EN-EL4 is not backwards-compatible with the EN-4. In other words, it's not possible to use the D2H's battery in the D1H, or the other way around. The D2H can also be powered by the 100-240V AC Adapter EH-6, via the DC-in port on the side of the camera. This adapter is different than the EH-4 used by D1-series cameras. In time, it's likely that cables for popular external battery packs will appear as well.