EOS 70D a New Benchmark in ISO Performance?

[jrista]

ISOs 6400+ seem to be slightly cleaner - but that's about it.

Probably the 70d has an added *real* analog iso6400 mode, while on the current 18mp sensor iso3200 is the highest setting and everything above is pushed *digitally* which you can also do in raw post w/ better results.

Actually, only expanded ISO modes on Canon's are pushed digitally. ISO settings above 1600 on most of their cameras (with the exceptions probably being the 1DX, 5DIII, and 6D) still use an analog amplifier for 2000, 2500, 3200, 4000, 5000, and 6400. It's just that it is a downstream amp. So it occurs after the sensor does its read, meaning any noise picked up between actual read and ADC is amplified again with that second amp. For RAW, the "digital" amp (any expanded ISO setting, i.e. 12800 or 25600) is really just a metadata marker that tells the RAW editor to perform the digital boost...which as you stated could be done by you in software anyway.

 

[blacksap]

I think the tests from the canon site are not a reliable tests, they look pretty good, but if the improvement is not good enough I think they would try to hide that fact, it would not be smart from them to give us reasons to start judging a camera that has not even made it yet to the market.

After taking pictures with my MKIII i went back to my 60d, I felt comfortable enough, obviously I missed the MKIII autofocus system and the high iso performance, so if the 70d has a little improvement on these areas I will happily use an APSC camera more often, specially with the release of the 18-35 1.8 (sharp) and covers my wide range pretty good, paired with my 50 1.4 on crop I think with this two lenses I will be able to achieve pretty good results on most of my stills and video projects (wedding pictures and videos).

Do you think that the dual pixel cmos will improve the AF system enough? will it be slightly slower than MKIII´s AF system?

And the AF system on video mode looks cool, you could avoid using a follow focus some times, but I think that in the end we will use the manual focus more than we think, all of my lenses are not STM so...

 

[jrista]

I think the tests from the canon site are not a reliable tests, they look pretty good, but if the improvement is not good enough I think they would try to hide that fact, it would not be smart from them to give us reasons to start judging a camera that has not even made it yet to the market.

After taking pictures with my MKIII i went back to my 60d, I felt comfortable enough, obviously I missed the MKIII autofocus system and the high iso performance, so if the 70d has a little improvement on these areas I will happily use an APSC camera more often, specially with the release of the 18-35 1.8 (sharp) and covers my wide range pretty good, paired with my 50 1.4 on crop I think with this two lenses I will be able to achieve pretty good results on most of my stills and video projects (wedding pictures and videos).

Do you think that the dual pixel cmos will improve the AF system enough? will it be slightly slower than MKIII´s AF system?

And the AF system on video mode looks cool, you could avoid using a follow focus some times, but I think that in the end we will use the manual focus more than we think, all of my lenses are not STM so...

The dual pixel AF system will only matter in live view mode, or when shooting video. If you continue to use the OVF, then the dedicated AF unit will still be used. For a lot of types of photography, you can only use the OFV, so the dual pixel system won't matter.

It should be noted that Canon's more advanced AF systems, including the 19pt AF from the 7D and the 61pt AF from the 1DX/5DIII use dual line sensors in the dedicated AF unit. That improves precision as well as consistency (apparently, considerably). Tests by LensRentals.com indicate that Canon's 61pt AF system is as accurate as CDAF in Live View, which is as accurate as ideal manual focus.

I would really just consider dual pixel FPPDAF to be just now starting to catch up to where dedicated AF units have been for a couple years at least. I don't know enough about Canon's approach to know if it could ultimately supplant dedicated AF units, thereby making high speed, consistent, usable for sports PDAF in mirrorless cameras a reality...only time will tell.

 

[Marsu42]

I think the tests from the canon site are not a reliable tests, they look pretty good, but if the improvement is not good enough I think they would try to hide that fact, it would not be smart from them to give us reasons to start judging a camera that has not even made it yet to the market.

They hide it in plain sight - Canon doesn't announce the 70d as a (significant) improvement in iso capability, and the two higher iso sample shots on their site are carefully selected to be very good nr'able.

Actually, only expanded ISO modes on Canon's are pushed digitally. ISO settings above 1600 on most of their cameras (with the exceptions probably being the 1DX, 5DIII, and 6D) still use an analog amplifier for 2000, 2500, 3200, 4000, 5000, and 6400. It's just that it is a downstream amp. So it occurs after the sensor does its read, meaning any noise picked up between actual read and ADC is amplified again with that second amp. For RAW, the "digital" amp (any expanded ISO setting, i.e. 12800 or 25600) is really just a metadata marker that tells the RAW editor to perform the digital boost...which as you stated could be done by you in software anyway.

Interesting, and contrary to what the Magic Lantern guys have figured out - they state that iso6400 also has the same data as iso3200, just moved around just like the expanded iso modes: http://magiclantern.wikia.com/wiki/ISO (see "http://magiclantern.wikia.com/wiki/ISO").

 

[jrista]

I think the tests from the canon site are not a reliable tests, they look pretty good, but if the improvement is not good enough I think they would try to hide that fact, it would not be smart from them to give us reasons to start judging a camera that has not even made it yet to the market.

They hide it in plain sight - Canon doesn't announce the 70d as a (significant) improvement in iso capability, and the two higher iso sample shots on their site are carefully selected to be very good nr'able.

Actually, only expanded ISO modes on Canon's are pushed digitally. ISO settings above 1600 on most of their cameras (with the exceptions probably being the 1DX, 5DIII, and 6D) still use an analog amplifier for 2000, 2500, 3200, 4000, 5000, and 6400. It's just that it is a downstream amp. So it occurs after the sensor does its read, meaning any noise picked up between actual read and ADC is amplified again with that second amp. For RAW, the "digital" amp (any expanded ISO setting, i.e. 12800 or 25600) is really just a metadata marker that tells the RAW editor to perform the digital boost...which as you stated could be done by you in software anyway.

Interesting, and contrary to what the Magic Lantern guys have figured out - they state that iso6400 also has the same data as iso3200, just moved around just like the expanded iso modes: http://magiclantern.wikia.com/wiki/ISO (see "http://magiclantern.wikia.com/wiki/ISO").

Actually, from what ML states, it sounds like every single ISO setting has a bit of digital push/pull. They pointed out that their tests seem to indicate DXO's measurements are pretty close to the actual hardware ISO values. If that is true, the 5D II ISO 6400 is actually a real ISO 3990, with a digital push the rest of the way. That would also mean that ISO 3200 is actually real ISO 2133 with a digital push the rest of the way, and that ISO 100 is real ISO 73 with a digital push the rest of the way. Who knows why Canon does that...but I guess its not surprising...they have had oddball ISO for years with their push/pull approach for third-stop settings anyway. (Would really be nice to see Canon stop cheating the ISO curve and just use per-pixel amplification for every single ISO setting.)

Most of the other ISO tests I've seen demonstrate what appears to be real DR falloff from ISO 100 through 6400, then a heel as the curve flattens when you hit expanded ISO settings (which literally are just an exact 1-stop or 2-stop digital push from the highest native setting.) There was another analysis done on how Canon achieves their ISO settings a few years ago that describes both per-pixel amps, a downstream amp, and digital boost. Who knows exactly how the downstream amp works, or what impact it has on ISO settings that use it.

 

[Marsu42]

Who knows exactly how the downstream amp works, or what impact it has on ISO settings that use it.

Hmmmyes, it's a bit frustrating to not know what's going on, my current consequence is (when shooting raw) only to use full iso stops and avoid 6400 on the 18mp crop sensor. But you're correct, the ml devs also figured out that using some of the oddball 1/3rd iso stops actually results in better iq for specific scenes, and this obviously means that there is more at play than we can figure out w/o the detailed hardware specs :-\

 

[jrista]

Who knows exactly how the downstream amp works, or what impact it has on ISO settings that use it.

Hmmmyes, it's a bit frustrating to not know what's going on, my current consequence is (when shooting raw) only to use full iso stops and avoid 6400 on the 18mp crop sensor. But you're correct, the ml devs also figured out that using some of the oddball 1/3rd iso stops actually results in better iq for specific scenes, and this obviously means that there is more at play than we can figure out w/o the detailed hardware specs :-\

Aye, I ultimately came to the same conclusion, to use only the full stop settings, and fix in post. It was very interesting what ML said about highlight headroom loss and harsh highlight falloff...it doesn't look like it is a ton, maybe a third to half a stop for all full stop ISO settings...but still, that is a third to half stop. I am seriously considering slapping ML on my 7D once I upgrade to a newer body...sounds like they have done some pretty good stuff with ISO.

The big thing on everyone's lips these days is DRivel, but ever since I first read about how Canon handles its ISO settings (and that was several years ago), its really been the thing that irks me most about them. It has always felt like the cheapest, most cheated thing Canon does in their cameras, and really the thing I wish they would improve most. I don't see why it is so difficult to build a sensor that amplifies to each ISO setting directly...seems a lot of other sensor manufacturers do it.

Maybe a shift to layered sensor technology will force Canon to change things up at a low level...

 

[Marsu42]

I don't see why it is so difficult to build a sensor that amplifies to each ISO setting directly...seems a lot of other sensor manufacturers do it.low level...

Isn't that what the 1dx sensor does, looking at the constant dr curve vs. other sensors zigzag? If so, maybe it's a budget thing, and a sensor with only so many discrete analog iso settings is easier to build and then the rest is done in the in-camera postprocessing chain. Plus the usual reason for "cheating" is marketing, i.e. hoping that people and non in-depth reviews won't stumble upon the fact that higher iso settings don't deliver the results you might expect from extrapolating.

 

[jrista]

I don't see why it is so difficult to build a sensor that amplifies to each ISO setting directly...seems a lot of other sensor manufacturers do it.low level...

Isn't that what the 1dx sensor does, looking at the constant dr curve vs. other sensors zigzag? If so, maybe it's a budget thing, and a sensor with only so many discrete analog iso settings is easier to build and then the rest is done in the in-camera postprocessing chain. Plus the usual reason for "cheating" is marketing, i.e. hoping that people and non in-depth reviews won't stumble upon the fact that higher iso settings don't deliver the results you might expect from extrapolating.

I think the 1D X still does the push/pull thing, its just far more refined and accurate, less detrimental. There was one test where you could see there were slight differences in each third stop setting, but to a degree far far less than any other Canon camera. That fits what people say about the 1D line...it has a considerable amount of extra polish and shine that the other cameras don't. I kind of wish that Canon would apply more polish and shine to the entire pro line. I don't think they are going to lose many people by doing so...so many people want a 1D X and simply cannot afford it...they effectively buy the most expensive they can afford (usually the 5D line.) I guess we'll see what Canon does with the 7D II when it comes out...maybe it will be polished a bit more.

 

[blacksap]

I think the tests from the canon site are not a reliable tests, they look pretty good, but if the improvement is not good enough I think they would try to hide that fact, it would not be smart from them to give us reasons to start judging a camera that has not even made it yet to the market.

After taking pictures with my MKIII i went back to my 60d, I felt comfortable enough, obviously I missed the MKIII autofocus system and the high iso performance, so if the 70d has a little improvement on these areas I will happily use an APSC camera more often, specially with the release of the 18-35 1.8 (sharp) and covers my wide range pretty good, paired with my 50 1.4 on crop I think with this two lenses I will be able to achieve pretty good results on most of my stills and video projects (wedding pictures and videos).

Do you think that the dual pixel cmos will improve the AF system enough? will it be slightly slower than MKIII´s AF system?

And the AF system on video mode looks cool, you could avoid using a follow focus some times, but I think that in the end we will use the manual focus more than we think, all of my lenses are not STM so...

The dual pixel AF system will only matter in live view mode, or when shooting video. If you continue to use the OVF, then the dedicated AF unit will still be used. For a lot of types of photography, you can only use the OFV, so the dual pixel system won't matter.

It should be noted that Canon's more advanced AF systems, including the 19pt AF from the 7D and the 61pt AF from the 1DX/5DIII use dual line sensors in the dedicated AF unit. That improves precision as well as consistency (apparently, considerably). Tests by LensRentals.com indicate that Canon's 61pt AF system is as accurate as CDAF in Live View, which is as accurate as ideal manual focus.

I would really just consider dual pixel FPPDAF to be just now starting to catch up to where dedicated AF units have been for a couple years at least. I don't know enough about Canon's approach to know if it could ultimately supplant dedicated AF units, thereby making high speed, consistent, usable for sports PDAF in mirrorless cameras a reality...only time will tell.

thank you for your explanation!!! now everything is clearer for me, and it does sound pretty neat!!

So who´s buying the 70d if the ISO performance is the same as 60d´s (or a small improvement)?

 

[Loswr]

So who´s buying the 70d if the ISO performance is the same as 60d´s (or a small improvement)?

The 5DIII was only a small improvement over the 5DII in terms of ISO performance. I think a few people bought 5DIIIs. :

 

[Marsu42]

So who´s buying the 70d if the ISO performance is the same as 60d´s (or a small improvement)?

The 5DIII was only a small improvement over the 5DII in terms of ISO performance. I think a few people bought 5DIIIs. :

Fair enough, but afaik the main concern with the 5d2 was the mediocre af performance, while with the 18mp crop sensor it's iso - so improving on the main shortcoming would be a good idea to make people upgrade from the previous generation.

Canon obviously opted for another thing, introducing a new technology which is also fine even if the dual pixel af isn't for me, but for iso the logical upgrade is still a ff and not a newer gen crop at least until the 7d2 is here.

 

[paul13walnut5]

So who´s buying the 70d if the ISO performance is the same as 60d´s (or a small improvement)?

Logical answer. Nobody is buying it yet

Logical answer no.2. People who have an older body than the 60D may buy the 70D

Logical answer no.3. People who benefit from the other improvements may buy the 70D

 

[Loswr]

So who´s buying the 70d if the ISO performance is the same as 60d´s (or a small improvement)?

The 5DIII was only a small improvement over the 5DII in terms of ISO performance. I think a few people bought 5DIIIs. :

Fair enough, but afaik the main concern with the 5d2 was the mediocre af performance, while with the 18mp crop sensor it's iso - so improving on the main shortcoming would be a good idea to make people upgrade from the previous generation.

Canon obviously opted for another thing, introducing a new technology which is also fine even if the dual pixel af isn't for me, but for iso the logical upgrade is still a ff and not a newer gen crop at least until the 7d2 is here.

The point is, the 5DIII didn't really improve IQ, it improved other stuff. The 70D is similar. Whether that other stuff is important enough to induce an upgrade is a personal decision.

I do think the 5DII -> 5DIII is a bigger jump than 60D -> 70D, but generally the longer the release cycle, the more significant the changes. Of course, what Canon really wants you to do is jump lines. Their strategy in recent years is consistent with that - the 60D wasn't really a 50D upgrade, that's the 7D.

 

[pedro]

So who´s buying the 70d if the ISO performance is the same as 60d´s (or a small improvement)?

The 5DIII was only a small improvement over the 5DII in terms of ISO performance. I think a few people bought 5DIIIs. :

Well, in my case the 5Diii was a huge improvement over the 30D 8)

 

[whothafunk]

ill probably make the jump from 550D to 70D. rubbery grip unglued everywhere on my 550D, its too small, and i need FPS, better AF and "better" ISO performance, even if only by small margin. i sometimes find 12800 not enough for indoor sports. some gyms are like dungeons.

i cannot wait for 7D2, and it will most probably be out of my budget area.

 

[rpt]

So who´s buying the 70d if the ISO performance is the same as 60d´s (or a small improvement)?

The 5DIII was only a small improvement over the 5DII in terms of ISO performance. I think a few people bought 5DIIIs. :

Well, in my case the 5Diii was a huge improvement over the 30D 8)

+1
My jump was from the 300D to the 5D3. Absolutely fantastic.

 

[johnhenry]

It would need some dramatic retooling of the sensor. Most gains of ISO are at the expense of more noise. You can play around in camera with binning etc but shirking pixel size means you need to add amplification to gain ISO

I find when I absolutely NEED better light gathering, I reach for my:

Monopod or tripod.

28mm f/2.0 West German Zeiss C/y mount with an adapter

85mm f/1.2 50th Anniversary Zeiss Planer with adapter

200mm f/1.8 Canon USM

 

[David Hull]

So who´s buying the 70d if the ISO performance is the same as 60d´s (or a small improvement)?

The 5DIII was only a small improvement over the 5DII in terms of ISO performance. I think a few people bought 5DIIIs. :

Yep... I fall into that group. I bought it (after the price dropped a bit) to get the better AF system, having had a 5DII for several years and knowing that it did an adequate job for what I needed to do. In other words since the horrible banding and inadequate DR that the 5DII was known to have ( ;-) ) had never really been a problem, I figured it would not be one in the 5DIII either.

A tad off topic, but worth mentioning I think, is how much better the metering seems to be in the 5DIII (from the 5DII) when I use it with flash. I think that the 5DIII / 600RT EX works about as well as any Nikon system I have ever used.

 

[x-vision]

Of course, what Canon really wants you to do is jump lines.

Agree completely.

Canon obviously considers the image quality of their crop cameras to be good enough.
Hence, they don't seem to be making much effort to improve it.

For better image quality, you are indeed invited you to jump lines ... by spending more .

Looking forward, I'm convinced that the 7DII will follow this pattern as well.
Unlike the 7D, the 7DII will use a different sensor than the rest of the crop models, IMO.
So, for better image quality in a crop camera, we'll all be invited to spend more on the 7DII - that is, to jump lines.