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Why are people assuming it would have the same size sensor as a Rebel? Smaller sensor = smaller camera.A DSLR with a smaller sensor? Mmmh... Not going to happen, IMO. It's not the trend we've been noticing recently. Everybody is asking for bigger sensors in non-reflex cameras, but I've never come across anybody foretelling a smaller sensor in a DSLR in any forum.
Yes, I DO mean native eos-M mount. Just to get the size down.It can't be a DSLR, then. Not enough room for a mirror.
Referring to new battery issue...Quite often, actually. Sanyo Eneloop. Never noticed differences in focusing speed or accuracy/precision, but I have a 5D II which, although having a very good center focus point, is not a champion with respect to keeper rate. Pros: you save a lot of money and have a higher capacity vs a single LP-E6 which enables a longer operating time. Cons: you miss the battery info, overall weight is (just a bit) higher and symbol in the LCD display indicates only full (4 bars) and half (2 bars) capacity; after that, the camera switches off without first showing 1 bar or the empty box.
My question, did you guys ever use the "AA" batteries (6 pieces) tray into grip when your LP-E6 run out? Any different in focusing??? Sometimes i use good batteries like Energizer, sometimes I used my Eneloop from 580EXII... Basically I dun feel any lag in focusing...
Focus is achieved by the movement of element group(s) within the lens. Canon EF lenses have a motor within the lens that moves the focusing group. The 1-series bodies are able to drive that motor faster. The camera tells the motor in the lens how far and which direction to move.
So that was always my understanding until I read this in the 400mm mk ii review over at TDP
Quote:
The 400 f/2.8 IS II has received some AF upgrades from the 400 f/2.8 IS I - new dedicated AF algorithms and a new high-speed CPU. How well they work is of course what is important.
So does this not indicate more intelligence in the lens. Anyone know for sure??
jrista, I was indeed thinking of you or Neuro when I wrote the highlighted sentence above, ha ha! Thanks for clarifying!Someone better skilled than me in physics please chime in and explain better, I'm sure there is. But we're going a bit off-topic here, I think.
I think the point BruinBear was trying to make was that you are conflating charge capacity with current flow. The term mAh is a measure of charge capacity over a period of time, and is not synonymous with mA, the actual current. The only time you would actually draw 27.195W is in the first moment of usage assuming you maximize the cameras' power draw for a moment. Actual voltage drops a little from the rated voltage, so on average you might, at full draw for some camera that actually needs 2.45amps, pull say 10.8V at 2.45A, for a power draw of 26.5W. I do not know of any reason you would be limited to 2450mA maximum current, however. Assuming you drained the battery in 30 minutes at 10.8v, you could draw ~5amps, or 53W!
Lithium battery voltage drops from the maximum rating to a slightly lower average during usage, peters off until it eventually drops off below a minimum safe level at which point a properly designed battery will usually shut off and stop supplying power. The math above is idealistic for constant power draw over a fixed period of time, and not actually representative of actual power draw by a camera in use. I honestly not sure what the actual power draw of a Canon 1D X is, however it is not continuous at a constant level...it bursts when the shutter is pressed, then drops to a lower ambient level.
Burst power draw in a 1D X, assuming max shutter speed, full AF drive of a 600mm f/4 L II lens, while tracking a moving subject, at full-size RAW+JPEG writing to two separate cards concurrently, could likely draw more than 26W. Assuming you actually draw 3400mA for a period of 8 seconds of continuous shooting like that, followed by idle draw of 20mA for 5 seconds, that would be say 10.8v times 3.4A for 0.002222 hours (36.7W over 8 seconds), 10.8v time 0.02A for 0.0014 hours (0.22W over 5 seconds), so ~37W, or 0.82Wh. (I've completely ignored resistance here...I don't know what kind of resistance you'ed have in something like the 1D X.)
I don't think I'm missing the point, the point is the lens motor is powered neither at 11.1 V nor at 7.2 V. It is powered at a voltage which I don't know, but which is undoubtedly the same whichever body you are using whith whatever battery voltage/number of batteries you are using. The lens is NOT powered directly from the battery, but from a circuit which delivers constant voltage whichever body/battery combo you are using.
If the lens motor was receiving the same power from a 1D X and a 7D, then the AF speed for the lens would be the same with both bodies. But it's not, it's faster with the 1D X.
Could it be firmware trickery on the part of Canon, the 7D delivers the same power as the 1D X, but the 7D just tells the lens to AF slower? Possible, I suppose...but that seems a little too cynical, even for me.
It appears to be a matter of old vs. new, 5DII/7D vs. 1DX/5DIII/6D, maybe both hardware and software. I truly believe it's not a matter of battery voltage, rather it may be the camera subsystems which drive the lens' AF.*UPDATE 2*
The battery does help a camera body autofocus an EF lens faster.
From Chuck Westfall… “In addition, the EOS-1D X achieves a higher lens motor drive speed with select L-series USM telephoto lenses than the 5D Mark III because of the 1D X’s more powerful battery pack.”
Exactly, power, i.e. V x A = W.
1 x LP-E4N is 11.1 V x 2450 mAh = 27.195 W
2 x LP-E6 is 7.2 V x 1600 mAh x 2 = 23.040 W
27 W vs. 23 W, not much of a difference, but it's there.
mAh is a measure of electrical charge and not max current output
I don't think I'm missing the point, the point is the lens motor is powered neither at 11.1 V nor at 7.2 V. It is powered at a voltage which I don't know, but which is undoubtedly the same whichever body you are using whith whatever battery voltage/number of batteries you are using. The lens is NOT powered directly from the battery, but from a circuit which delivers constant voltage whichever body/battery combo you are using.You missed the point, battery capacity has little effect, its the current driving the lens motor, and that is based on the voltage and resistance using ohm's law E=IR.*UPDATE 2*
The battery does help a camera body autofocus an EF lens faster.
From Chuck Westfall… “In addition, the EOS-1D X achieves a higher lens motor drive speed with select L-series USM telephoto lenses than the 5D Mark III because of the 1D X’s more powerful battery pack.”
Exactly, power, i.e. V x A = W.
1 x LP-E4N is 11.1 V x 2450 mAh = 27.195 W
2 x LP-E6 is 7.2 V x 1600 mAh x 2 = 23.040 W
27 W vs. 23 W, not much of a difference, but it's there.
Given the same internal resistance of the lens motor, the current would be about 11.1/7.2 times larger or 1.52 times as much current going thru the motor. Presumably the internal resistance of the bigger battery is lower, so it would have little effect.
That will drive the motor much faster.
out of interest, how many people use a grip on their 7D mark 1 that don't want a want an integrated grip on the 7D mark 2?Since I have expressed a preference for a detachable grip, I feel impelled to circumstantiate my choice. I have a 5DII with grip which is on 90% of the time. Occasionally, I remove it and go light with a single lens, which is a great advantage sometimes, IMO. Plus, I can delay the grip purchase, diluting the expense over time. Moreover, while I can imagine Canon charging $ 3500-4000 for an integrated grip body, though crop, I don't think they'll dare asking as much for an ungripped body + grip, it's a matter of psychology, also. That said, I'd go for the integrated grip if that'll be Canon's offer and sure won't complain!
*UPDATE 2*
The battery does help a camera body autofocus an EF lens faster.
From Chuck Westfall… “In addition, the EOS-1D X achieves a higher lens motor drive speed with select L-series USM telephoto lenses than the 5D Mark III because of the 1D X’s more powerful battery pack.”
...the single battery of a 1-series does drive the lens AF motor faster than the pair of batteries used in a grip. This is evident when a 'slow focusing' lens like the 85L II (where the focusing group movement is visible and slow enough to be easily seen) is focused from MFD to infinity on the 1D X vs. a gripped 7D, with fresh batteries. I'm not sure about the electronic basis for the difference in AF speed (current draw or firmware), but the difference is there.
We’re told that the larger battery seen in the EOS-1D X is part of the reason it will autofocus bigger lenses better than a camera with say an LP-E6.
Which means using 2xLP-E6 in the grip should allow the same autofocus performance, and, I would add, should also allow driving a burst speed of 12+ fps, a feature which would draw even more current than a big lens AF.
No, dual LP-E6 ≠ one LP-E4N. With two batteries in a grip, the voltage output of them is not added, they are used in an alternating sequence. The 1-series bodies drive lens AF motors faster because the battery delivers a higher voltage.
It should have nothing to do with the fps, either - adding a grip to a dSLR isn't required for higher frame rate AFAIK (although it was with film bodies to drive the film winder faster). Even with Nikon bodies where the grip provides a higher frame rate, there's a firmware hack that enables that higher frame rate without the grip, i.e. the higher frame rate with grip is a Nikon marketing ploy to sell an expensive accessory.
We’re told at least one variation of the camera being developed has an integrated grip
We’re told that the larger battery seen in the EOS-1D X is part of the reason it will autofocus bigger lenses better than a camera with say an LP-E6.
But I'm figuring its release not earlier than 2014. 
I could see the 70D being what an incremental update to what the 7D might have been.
If Canon is about to introduce a new sensor technology in the 7D Mk II, there's no reason not to throw the best of the outgoing generation's tech at the 70D. I have no idea how much improvement's possible, but Canon managed to milk sensor-level improvements moving between the 1Ds Mk III/ 5D Mk II sensors to the 5D Mk III/ 1D X sensors. Since all of those models were derived from the same process, I think it's reasonable to assume Canon can produce an improved ASP-C sensor without dipping into 7D Mk II tech. And that's just hardware-level tech. If they decide to throw a 5+ chip in, it might be a decent performer, even by modern standards. It won't be able to reach Nikon's dynamic range but if it competes on resolution and offers superior or equal low light, it will be the best APS-C sensor Canon has produced to date, and a legitimate reason for many Rebel, XXD and 7D shooters to upgrade.
The 70D could also have: the 7D's AF, All-I and IPB video codecs at the typical frame rates, tele/wide AFMA, WiFi, GPS, 7 fps, build quality similar to the 50D, various perks like built-in HDR, etc.
At $1200 or so, that doesn't beat the D7100 on paper, per se, but given recent history, it would be competitive enough. If Canon goes nuts and releases it at $1000 or something, it sounds like a great deal.
The 7D Mark II, meanwhile, could debut the allegedly awesome new sensor tech. It could also have robust build and sealing, 1D X/ 5D Mark III-style AF, 10 fps, and maybe even the 1D X metering. Several rumors have mentioned video, which makes one imagine Canon's going beyond the status quo here. This could be anything from 1080p at 60fps to better resolution (e.g. the 1D C Super 35 crop mode). This theoretical 7D Mk II would be an obvious upgrade for holdout 7D owners. It would also compel attention from the video crowd, even if they already have 5D Mark IIIs. More importantly, it would do so without stepping on the C line's toes. It would also be a nice jump for advanced Rebel users, as well as 60D holdouts. And I could see lots of full frame owners picking up one of these as a second body.
I don't have a speck of evidence for any of this. But it seems reasonable enough to me, and if my intuition is correct, I'd consider the 70D a respectable camera. Not cutting edge but a solid step up for a lot of current users.
Agree with those saying that the 70D will not have a new sensor. The 70D can't be perceived by customers as the top of the line APS-C. But given how old the 7D1 is, people may believe that the 70D is better anyway.
For that reason, I'm really surprised the 7D2 isn't coming out before the 70D. It's far more logical to go like this:
Lead with 7D2 --> extra processor for highest burst, brand spanking new sensor, 1DX / 5D3 AF, high-end $2k offering, etc.
Stagger 70D 6-12 months later --> just one processor for modest burst, that same 7D2 sensor, a 7D1-like AF
Stagger the next Rebel after that --> same 7D2 sensor but with nerfed AF and burst
- A
No one can prove that the March DSLR isn't the 7d2
It's far more logical to go like this:
Lead with 7D2 --> extra processor for highest burst, brand spanking new sensor, 1DX / 5D3 AF, high-end $2k offering, etc.
Stagger 70D 6-12 months later --> just one processor for modest burst, that same 7D2 sensor, a 7D1-like AF
Stagger the next Rebel after that --> same 7D2 sensor but with nerfed AF and burst
- A
