Canon Intros EOS 1D Mark IV DSLR with HD Shooting, Extreme ISO Capabilities, and Revamped Autofocus System
Oct 19, 2009
By Dan Havlik, PDN's Technology Specialist
The new DSLR, which features a revamped autofocus system and HD shooting capabilities, is the replacement for the 10MP 1D Mark III.
Though it's been over two years since the Mark III camera out, little has changed superficially with the new Mark IV model. The two cameras look almost exactly alike though the new 1D Mark IV has three dots below the EOS-1 logo to identify the microphone.
Yes, that monaural microphone is there to support the Mark IV's new High Definition movie mode which is very similar to the video capabilities of the recently announced Canon EOS 7D.
Like the 7D, the 1D Mark IV can shoot 1080p video in frame rates of approximately 30fps, 25fps, and 24fps. It can also record 720p HD video at 60fps and features a stereo mic jack.
Along with sharing the same 10fps still shooting speed of the Mark III, the new Mark IV's sensor is also a non-full-frame APS-H (27.9 x 18.6mm) size with a magnification factor or 1.3x.
Revamped Autofocus System
What the 1D Mark IV doesn't share with its predecessor or the 7D is a completely redesigned 45-point autofocus system with 39 cross-type focusing points. (The Mark III had 19 cross-type points and the Mark II had only seven.) The new system also features a new focusing algorithm called AI Servo II.
"The purpose is to substantially increase the percentage of in-focus shots," said Chuck Westfall, Technical Advisor in the Professional Products Marketing Division at Canon U.S.A. "We are revising the algorithm so it makes better decisions in a variety of ways with moving subjects. We've redesigned it in such a way that we feel it will be far more consistent and stable."
Though the Mark III's speed and rugged build made it suited for shooting sports as well as for photojournalism, the camera's autofocus system came under withering criticism from some photographers and websites for being inconsistent and inaccurate. The revamped AF system in the Mark IV is clearly an attempt by Canon to make photographers forget about the past.
"We heard a lot of different things about the 1D Mark III," Westfall said. "People wanted to have have more consistent and reliable performance and after going through it very responsibly, we knew it had to be not just a hardware and a software upgrade, but a complete upgrade."
Extreme ISO Shooting
Canon has also broadened the 1D Mark IV's ISO range, offering ISO 100-12,800 in standard mode in addition to a specialty low setting of ISO 50 and a boosted high of ISO 102,400. (Just last week, Nikon released the D3s digital SLR which can also shoot at ISO 102,400.)
It will be interesting to see how the 1D Mark IV handles image noise -- especially at the extreme ISO levels -- given that the increased resolution has lowered pixel size to 5.7 microns compared to 7.2 microns on the Mark III. (In contrast, the full frame 5D Mark II has a pixel size of 6.45 microns while the 7D is at 4.3 microns per pixel.)
The shooting buffer on the 1D Mark IV is a maximum of 121 JPEGs or 28 RAW images in a continuous burst. The RAW + JPEG buffer limit is 20 frames.
To achieve its speed whether shooting 10fps, 1080p HD video, or 14-bit RAW images, the 1D Mark IV has dual Digic IV image processors which gives the camera 6x the processor power of the Mark III.
"That's the way we're able to cope with the extreme amount of throughput on this camera," Westfall said.
Despite the extra processing power of the the two Digic IV chips, the 1D Mark IV's frame rate did not receive the perfunctory boost from the previous model.
Westfall said increasing the speed further may have caused additional wear and tear on the camera's mirror box. "And honestly, 10 frames per second is just about as fast as you can run one of those things and still have the autofocus see each shot shot."
The LCD screen has been upgraded on the 1D Mark IV to 3-inches in size with 920,000 dots of resolution. Canon has also put a layer of optical resin between the cover plate and the LCD to help eliminate reflections for better viewing in bright light.
The Mark IV's camera body has a magnesium alloy inner and outer covers along with a magnesium alloy chassis with a magnesium alloy mirror box. (Yes, that's a lot of magnesium alloy!) It's also fully weather sealed.
Along with the 1D Mark IV, Canon also announced the WFT-ES II A wireless file transmitter for DSLRs this morning.