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Canon EOS Crop Sensor for HD
APS-C sensor cameras including the 80D, 70D, 7D Mk. II, 7D, EOS M and Rebel models for HD video recording.


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Old December 23rd, 2009, 11:30 AM   #16
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Jean-Philippe and Khoi

Not to belabor the point, but the Sony EX1's maximum aperture is 1.9, which is just a touch over 1 stop difference from f2.8. If the 7D is at least 1 stop faster than the EX1 I should be able to get the same noise levels from a f2.8 lens, no?

I'd like to hear from owners of both the EX1 and 7D's to see if they've got any opinions on this. I'm just stating my own personal real-world comparison, I haven't put up charts, scopes and the like to really compare them, this is just my intuitive impression based on a few shoots in less than ideal light. I could be totally wrong, but I don't 'feel' like I am.

I own a 7D so I want to be able to use it to the fullest, so I think this discussion is good. And I'm already shooting with the suggestions above, though I've been using the '320 ISO' multiples rule from previous advice rather than the '200' multiples rule from David Chapman.
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Old December 23rd, 2009, 11:53 AM   #17
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Think of it this way, if you want to use the 7D in low light, you want to give it the best lens for the situation, so don't cripple it by using 2.8 lens in low light, put a 1.8, 1.4 1.2 on it and you will see it shine, you wouldn't put regular gas in a racing car would you? if you are under good light then you can put your 2.8 lens so you have a benefit of zoom lens.
Try a Sigma 30mm 1.4 for low light reception work, it is cheap about $400.00, a lot cheaper than your 2 zoom lens and twice as bright. There are plenty of shortconmig with 7D but low light is not one of them. BTW a friend brought over his EX1 and we compared it side by side and he agreed that EX1 can't match 7D in low light if you have a fast lens.
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Old December 23rd, 2009, 12:01 PM   #18
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EX-1, 7D, and GH-1 low light performance

Quote:
Originally Posted by Keith Moreau View Post
Jean-Philippe and Khoi

Not to belabor the point, but the Sony EX1's maximum aperture is 1.9, which is just a touch over 1 stop difference from f2.8. If the 7D is at least 1 stop faster than the EX1 I should be able to get the same noise levels from a f2.8 lens, no?

I'd like to hear from owners of both the EX1 and 7D's to see if they've got any opinions on this. I'm just stating my own personal real-world comparison, I haven't put up charts, scopes and the like to really compare them, this is just my intuitive impression based on a few shoots in less than ideal light. I could be totally wrong, but I don't 'feel' like I am.

I own a 7D so I want to be able to use it to the fullest, so I think this discussion is good. And I'm already shooting with the suggestions above, though I've been using the '320 ISO' multiples rule from previous advice rather than the '200' multiples rule from David Chapman.
In my "non scentific" opinion, I get better results with the EX-1 in low light than the 7D (I have a Tamron 17-50, 2.8 though). The surprising thing is that, again, according to my own experience, the GH-1, equipped with the new Olympus pancake lens (20mm, f2.8), during an indoor night scene, apperars to be better in low light than the 7D. I don't know exactly the size of the light diods on the gh1 compared to the 7D, but I definitely had more light into that little camera than the 7D (same exposure, same shutter speed, neutral pp etc.. Any comments in regards?? I am here to learn.
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Old December 23rd, 2009, 12:31 PM   #19
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Quote:
Originally Posted by Khoi Pham View Post
Think of it this way, if you want to use the 7D in low light, you want to give it the best lens for the situation, so don't cripple it by using 2.8 lens in low light, put a 1.8, 1.4 1.2 on it and you will see it shine, you wouldn't put regular gas in a racing car would you? if you are under good light then you can put your 2.8 lens so you have a benefit of zoom lens.
Try a Sigma 30mm 1.4 for low light reception work, it is cheap about $400.00, a lot cheaper than your 2 zoom lens and twice as bright. There are plenty of shortconmig with 7D but low light is not one of them. BTW a friend brought over his EX1 and we compared it side by side and he agreed that EX1 can't match 7D in low light if you have a fast lens.
Thanks for the test and yes I know that if you really want low light operation go with faster glass. Soooo... What ISO do you stop at because of noise in your 7D? To everyone that has replied thanks for the input. BTW if anyone thinks that this is somehow 7D bashing they are VERY wrong I love this camera!! But I do want to wring everything I can out of it and knowing it's limitations is part of that process.
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Old December 23rd, 2009, 12:36 PM   #20
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You guys must remember that an F/stop wont tell you how much light is hitting the sensor, you need T/stops for that. An F/stop is just a simple expression of the size of the aperture in relation to focal length.

You can take two f.2.8 lenses pop them on the same camera and get very different results. Indeed, zoom lenses differ dramatically compared to primes.

I'll wager that the above mentioned Tamron is closer to T.4 than T2.8 and that little pancake lens is pretty close to T2.8.

What I can say for sure, having tested it, is the 5D is marginally better than the 7D in low-light and that the 7D, 5D and EX1 all perform incredibly well in low-light compared to most other cameras on the market.
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Old December 23rd, 2009, 12:48 PM   #21
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Liam you are right about the specs of lenses being all over the place despite what is slapped on the side of them, but many independent test put the Tamron at f3.0 (very close to as advertised)
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Old December 23rd, 2009, 12:50 PM   #22
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"You guys must remember that an F/stop wont tell you how much light is hitting the sensor, you need T/stops for that. An F/stop is just a simple expression of the size of the aperture in relation to focal length.

You can take two f.2.8 lenses pop them on the same camera and get very different results. Indeed, zoom lenses differ dramatically compared to primes.

I'll wager that the above mentioned Tamron is closer to T.4 than T2.8 and that little pancake lens is pretty close to T2.8.

What I can say for sure, having tested it, is the 5D is marginally better than the 7D in low-light and that the 7D, 5D and EX1 all perform incredibly well in low-light compared to most other cameras on the market." -Liam Hall

Well said, a primary reason for abandoning the whole fstop measurement altogether. Coming from an HVX200 that I still use occasionally, the 7D is like seeing in the dark. I usually shoot at ISO400, but have gone up to ISO800 and VERY occasionally ISO1000. This all using an L series 24-70 f2.8
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Old December 23rd, 2009, 01:07 PM   #23
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Quote:
Originally Posted by Keith Moreau View Post
Not to belabor the point, but the Sony EX1's maximum aperture is 1.9, which is just a touch over 1 stop difference from f2.8.
Only at the very widest angle. As you zoom in, the lens's maximum iris shrinks (even though it doesn't tell you that it's happening). At full telephoto it's probably f/2.8.

I will, however, back you up on the assertion about video noise vs. a video camera. I tested with my HPX170 and found that at equivalent ISO levels, the 7D and HPX170 delivered about equivalent noise. There's not anything "magical" happening in the signal just because it's an SLR! The difference in low light performance is the ability to use faster lenses. An f/1.4 lens is two full stops faster than an f/2.8, which is probably about where we normally sit on a video camera, so that 1.4 lens is letting in four times as much light as the video camera is seeing.

But put them at the same f-stop*, at the same ISO (using 400 as the base ISO on an EX1 in 1080p mode, and each 6dB of gain doubling that ISO) and you will see about the same, or perhaps less, noise on the EX1.

*and again, it's pretty much impossible to tell what f-stop an EX1 is at, if you have it wide open. Set it on 2.8 if you want consistent results throughout the zoom range.
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Old December 23rd, 2009, 01:50 PM   #24
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Quote:
Originally Posted by Jerry Porter View Post
Liam you are right about the specs of lenses being all over the place despite what is slapped on the side of them, but many independent test put the Tamron at f3.0 (very close to as advertised)
Then I'd have lost my bet:)

BTW. It's not that the specs of lenses are all over the place. An f/stop is an f/stop and we still need to know the f/stop to work out DoF. But, since lens designs differ dramatically - in terms of number of elements, amount of internal reflection and so on - so does their light gathering performance.

I think the low-light performance of the 7D is astounding and just because there are a couple of other, more expensive, cameras that are marginally better doesn't make it any less astounding.
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Old December 30th, 2009, 04:11 PM   #25
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I've spent hours on Vimeo looking at EX1 and EX3 shots compared to the 5DII. What I see with the EX1 in particular is no detail in the shadows. That's likely from some kind of active noise reduction.
But what I saw mostly is that the 5DII was far better in good natural light: golden hour around sunrise and sunset, a medium lit restaurant - these sorts of situation. In bright light, the video was much closer in quality.
There are many, many examples of 5DII and 7D footage that look nothing like what comes out of any of the Sony EXs. So it's really a craft issue - setting, lenses, post adjustments.
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Old January 2nd, 2010, 03:07 PM   #26
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The stock lens on the Ex1R

Fujinon 14x Optical Zoom with Image Stabilization 5.8-81.2mm, f/1.9 is actually fairly fast. So in order to compare apples with apples one must use at least a f/1.8 as a f/2.8 would allow what, 1/2 the amount of light in ?

T stop - interesting. I'll have to research this more. To utilize this camera does require a healthy working knowledge of lenses!
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Old January 2nd, 2010, 06:04 PM   #27
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Did anyone answer about the ISO? In case it wasn't covered, this is why I do what I do...

I said before that I shoot 100, 200, 400, 800, 1600, etc with highlight tone priority off. The "why" is that the 7D doesn't support anything other than those values. And actually, doesn't necessarily support ISO 100.

David, shut up. You don't know.

Okay, so...

1. The +1/3 EV ISO steps (125, 250) reduce the dynamic range by 1/3 EV

2. The -1/3 EV steps (160, 320) cause an "overmetering: by 1/3 EV and causes clipping sooner (why noise tests on these steps seem free of noise—they are clipped off)

3. ISO 100 and 125 cause ruffly 1/4 EV higher exposure than it should, making 100 = 119 and metering for 100 may cause overexposure.

4. HTP = Not for David. Why? I don't like noise in my blacks. I thought at first that HTP would under-expose the high end of the curve. Well no. It underexposes the whole curve, then boosts the blacks digitally showing off more noise. I'd rather expose correctly and boost in post instead of gasp over tiny mites crawling over what should be a great-looking shot. Maybe HTP should be on at ISO 1600+ (HTP+1600=3200 with less noise).

My new ISO numbers with no HTP:
200, 400, 800, 1600
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Old January 15th, 2010, 06:58 PM   #28
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Hey, try this.

In the menu, second list from the right, check AUTO LIGHTING OPTIMIZER. Set this to OFF instead of STANDARD. This can boost the darks adding noise in low-ISO settings.
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Old January 16th, 2010, 07:55 AM   #29
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That was one of the first things I did and it makes a BIG difference!!
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Old January 16th, 2010, 08:24 AM   #30
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Actually it's in the menu list under the second tab over from the LEFT..., but yes it works as described!
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