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Old Sep 4, 2013, 9:43 PM   #11
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First, the 70D has a 20MP sensor, while the D7100 has a 24MP sensor. There's no way to make a direct comparison visually between images captured from the two cameras, especially via the limited resolution of a webpage. Either or both would have to be downsampled which could favor one or the other arbitrarily.

The best comparison is one that would measure the signal-to-noise ratio of each of the two cameras independently, and compare the objective results. That's what DxOMark does. Click on the Measurements tab, then the SNR 18% link. What you'll see there is that the difference in the signal-to-noise ratios between the two is miniscule, but if you want to say that one is better than the other, then it's the Nikon. But on top of that, the Nikon has greater resolution, so the individual errant pixels will be smaller in images captured with the Nikon, and therefore less obtrusive.

But the real difference comes on the next chart: Dynamic Range. This is a measure of the difference between the brightest and dimmest portions of a captured image, and here, the Nikon runs rings around the Canon, especially at the lower end of the scale where you'd likely do most of your shooting.

So, on the face of it, the D7100 is a better camera than the Canon 70D, based entirely on objective tests of sensor performance.

But if you can't get good quality lenses for the subjects you want to shoot, then the quality of the sensor doesn't matter.

So, what do you want to shoot?
For Real? I want to learn how to shoot!
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Old Sep 5, 2013, 3:38 AM   #12
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Learning to shoot with a D7100 or a 70D is like learning to drive with a tractor-trailer or learning to fly with a 747. Somewhere along the line, you've figured out that you want a dSLR. Is it just a status thing, or are there things that you couldn't do with your sx50HS that you need a dSLR for?

As for videos, one of the things that makes dSLRs not a good choice is that most lenses don't have very good zoom range, so having to stop shooting a video so you can change lenses can disrupt the flow of the video, and often the event you're trying to record. And lenses that do have good zoom ranges, aren't very good for still images, especially for cameras with high resolution image sensors. If your primary objective is to shoot videos, I suggest you get a good video camera, maybe one that can shoot reasonably good stills.

Another factor when shooting videos with a dSLR is the noise the lens makes while focusing (and zooming, for power zoom lenses.) Canon's USM and STM lenses and Nikon's AF-S lenses are quite, as are Sigma's HSM and Tamron's USD lenses, so finding one of those lenses with a good zoom range would help.

But using a 20MP or 24MP dSLR to produce 2MP (1920x1080) videos is a bit of a waste.
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Old Sep 5, 2013, 4:16 AM   #13
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Thanks for the replies, ive been reading a lot about the two,

and things like this make me think that the 70d is the one:http://www.michaelthemaven.com/?post...so-noise-chart
It's interesting isn't it- how DXO seems to score the Nikon higher with regards noise, yet on the sample images I've seen- and with the examples you've shown,it would suggest the Canon has the edge- and given that the Canon examples are cropped heavier (due to lower resolution) to match the same size for comparison,that should hinder it further- yet doesn't seem to..!!
Even the apparent shortcomings the 70D seems to have in the DR dept' can be pretty much overcome by using the HTP feature, generally pulling in an extra stop of highlight range.
Again,though,both great cameras- capable of great results in the right hands.

TcCav's point about the video is a valid one, given the relatively low resolution of the video, a high res' sensor is a bit of overkill really- and unless I was doing something creative at close quarters with a prime lens/manual focus, I wouldn't be looking at a DSLR for video (which I don't anyway...!).
The potential is there for great video- but requires quite a bit of effort,skill- and expense..!

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Old Sep 5, 2013, 5:52 AM   #14
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Back to the sample images, notice that the images from the Canon seem to be very slightly brighter than those from the Nikon. Since noise manifests itself almost invariably as pixels that are brighter than normal, a brighter image would always appear to have less noise than a dimmer one.

Since, unlike P&S cameras, dSLRs vary their exposure by 1/3 stops, getting images of absolutely equal brightness from two different cameras with two different lenses is extremely unlikely. Thus, side-by-side comparisons that are complicated by variations in brightness are highly flawed.
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Old Sep 5, 2013, 5:59 AM   #15
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Learning to shoot with a D7100 or a 70D is like learning to drive with a tractor-trailer or learning to fly with a 747. Somewhere along the line, you've figured out that you want a dSLR. Is it just a status thing, or are there things that you couldn't do with your sx50HS that you need a dSLR for?

As for videos, one of the things that makes dSLRs not a good choice is that most lenses don't have very good zoom range, so having to stop shooting a video so you can change lenses can disrupt the flow of the video, and often the event you're trying to record. And lenses that do have good zoom ranges, aren't very good for still images, especially for cameras with high resolution image sensors. If your primary objective is to shoot videos, I suggest you get a good video camera, maybe one that can shoot reasonably good stills.

Another factor when shooting videos with a dSLR is the noise the lens makes while focusing (and zooming, for power zoom lenses.) Canon's USM and STM lenses and Nikon's AF-S lenses are quite, as are Sigma's HSM and Tamron's USD lenses, so finding one of those lenses with a good zoom range would help.

But using a 20MP or 24MP dSLR to produce 2MP (1920x1080) videos is a bit of a waste.
I cant argue with you guys since i just started to learn about DSLR ... but i've seen videos from 70d with the kit lenses and they are just perfect to me, the autofocus works so great and with the stm lens you cant hear the lens at all ... as i said there somthings like magnesium body from the 7100 that make it looks more professional or time proof ... they say that 7100 is the closest you get from a full frame without buy one... but i think ill get 70d with the B&H kit. Thank you guys.

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Old Sep 5, 2013, 8:47 AM   #16
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You started out with your selection narrowed to two excellent cameras. There's no way you could make a bad choice. I hope it works out for you.
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Old Sep 6, 2013, 8:44 AM   #17
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You started out with your selection narrowed to two excellent cameras. There's no way you could make a bad choice. I hope it works out for you.
Thanks...now i wonder if i need to buy an extreme pro card with 90 mb/s , since my older sandisk ultra do 30 mb/s... in my old sx50hs worked fine, but to shoot with this 70d i think will be a bottleneck.
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Old Sep 6, 2013, 11:16 AM   #18
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With the larger files and the faster burst performance, I'd say get a faster card.
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Old Sep 6, 2013, 11:21 AM   #19
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well i found something good: http://m.youtube.com/watch?v=TuEtZb3...%3DTuEtZb3ZNLA
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Old Sep 6, 2013, 1:27 PM   #20
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  1. Smaller cards are faster than larger cards. That's always been the case. His test uses different size cards for comparison, and that lessens the validity of what he's doing.
  2. Speed is important, and SanDisk Extreme Pro and Lexar Professional SD cards always perform at least as well as anybody else's. But what's more important is that you should never get a card that's larger than you can afford to lose, because reliability varies greatly from brand to brand. Flash memory locations fail with anybody's cards. What counts is how many spare memory locations are on the card. SanDisk and Lexar put as many as anybody else does, and more than most.
So, SanDisk and Lexar cards are among the fastest and among the most reliable.
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