A Few 60D Specs [CR2]

[that1guy]

This was the sample I had seen a while ago showing the noise difference between the 7D and the 5D mkII.

http://www.cameratown.com/reviews/canon7d/

As you can see the 7D actually does pretty well. I'm not saying that it doesn't do ok (I think I might have ruffled some feathers before ), I'm just saying that I would prefer something that is better than that. Anyway, going based on arguments, more pixels are better than fewer with low noise. My thought is, why not have more pixels and less noise. I am of the opinion that if you can have less pixel density you will have a better photo. I think that is one of the reasons why the 5DmkII has better image quality. The "more pixels is better crowd" might argue that the 5DII has more pixels, but come on, it is only 3mp more (which isn't that much) and when you look at the pixel level the 5DII really is doing better.

Another problem with a more tightly packed sensor is diffraction, but that is a whole other topic. I don't know all of the technical end of it, and I don't want to start a big argument, so I'll quit w/ it here. Just wanted to show that the less density/better pixels crowd has a good point too

The other thing I will throw out there is this...we all have different needs. Some people need a camera that has a better looking image when viewed at 100% (stock photographers would be a good example), other people need a fast performing camera that will get the photo in the instant and make a nice print (wedding photographers great example here). I hope no one thinks I'm bashing one choice over another...just trying to point out why I made mine

Oh, and I just found one more thing that proved me wrong on an earlier thought I had...DxO Mark is an independent lab that tests camera sensors for all kinds of things (sn ratio, dynamic range, tonal range, color sensitivity, etc). The 7D actually does beat the 40D on most accounts, so that changed my mind there. A 1D mkiv (a camera that came out around the same time so technology is on a more level field) did beat the 7D by quite a margin. Is it better technology, or a less dense sensor, or both? I don't know, food for thought though. If anyone is curious, they can check the DxO site. It is pretty cool, you can compare up to three cameras side by side. Here's the link: http://www.dxomark.com/index.php/en/Camera-Sensor/Compare-sensors

 

[Jan]

If they don't release a new FF camera by the time I actually need a camera, I am thinking of just picking up a 40D as a cheap way to hold me over until a camera I really want comes out. Like you, I think it handles noise very nicely, and you can get them really cheap now.

You're not really saying that a 40D offers better image quality at lets say 3000x2000 px than a 7D, are you?

Edit: oh, sorry, I didn't read your last post. Never mind.

 

[Jan]

18mp (Exact same as the 7D & T2i)

Exact the same as 7D/550D? Wasn't there a difference between these two sensors? I remember having read this somewhere...

 

[unfocused]

Wasn't there a difference between these two sensors?

It appears you are correct. At least, several websites say the sensors are different "according to Canon." However, no one seems to be able to explain what the differences are. Perhaps the difference is that one sensor is in the 7D and one is in the T2i.

 

[J]

This is just hearsay, but I recall reading somewhere that the difference was on the back-end. The 7D is dual processor and the T2i is single processor, so the difference is that there are half the data channels (i.e. the sensor outputs data more slowly). Technically that would be a "different" sensor, just not so much regarding IQ.

 

[Woody]

As you can see the 7D actually does pretty well. I'm not saying that it doesn't do ok (I think I might have ruffled some feathers before ), I'm just saying that I would prefer something that is better than that.

I'm not a big fan of 7D, but it's nothing to do with image quality. So, I am not upset by what you say about the 7D. However, the belief that high pixel density automatically translates into poorer IMAGE quality is a myth.

This was the sample I had seen a while ago showing the noise difference between the 7D and the 5D mkII.
http://www.cameratown.com/reviews/canon7d/
... I think that is one of the reasons why the 5DmkII has better image quality. The "more pixels is better crowd" might argue that the 5DII has more pixels, but come on, it is only 3mp more (which isn't that much) and when you look at the pixel level the 5DII really is doing better.

While the 5D2 may be better because it has a larger sensor (nothing to do with its absolute pixel count), the difference is really not astounding (i.e., definitely not 2 to 3 stops better like what many people think). Let me quote from your web link:

"While the differences aren't HUGE, the 5D Mark II's full-size sensor definitely made a difference at ISO 3200 and beyond. Of course that means both cameras were fairly well matched up through ISO 1600, not an easy feat for an 18MP cropped-sensor camera."

I should also point out that in the above link, the 7D shots are darker (i.e., lower exposure) than the 5D2.

Another problem with a more tightly packed sensor is diffraction, but that is a whole other topic. I don't know all of the technical end of it, and I don't want to start a big argument, so I'll quit w/ it here. Just wanted to show that the less density/better pixels crowd has a good point too

That is a myth that can be debunked most easily. If you compare images from the 12 MP 450D against the 18 MP 7D side-by-side, all the way from f/2.8 to f/16 using the same lens,
you'll see they are EQUALLY affected by diffraction beyond f/8. The 7D is not in any way worse. Some other points to note:

(a) diffraction occurs at the lens, and the sensor merely records what has already taken place
(b) diffraction believers forget about the AA filter in front of the sensor, its strength can be lowered with increasing pixel density

Oh, and I just found one more thing that proved me wrong on an earlier thought I had...DxO Mark is an independent lab that tests camera sensors for all kinds of things (sn ratio, dynamic range, tonal range, color sensitivity, etc).

DXOMark is full of garbage. Their numbers have no real world meaning (in fact, they contradict what you actually SEE from DPReview etc) and they are not even self-consistent. I do not wish to go into all the gory details here unless you really want me to.

 

[Woody]

This is just hearsay, but I recall reading somewhere that the difference was on the back-end. The 7D is dual processor and the T2i is single processor, so the difference is that there are half the data channels (i.e. the sensor outputs data more slowly). Technically that would be a "different" sensor, just not so much regarding IQ.

Yes, that is nearly correct. The 7D sensor has two channel outputs for faster frame rate while the T2i only has one.

 

[that1guy]

Hey Woody,
I really would be interested in reading more, and seeing more comparisons on diffraction. Everything I have read and seen says that it gets worse on dense sensors, but this is one of those things where I would love to be proven wrong. It would make my life better, especially since it seems sensors are getting packed tighter and tighter these days Any info, links and photo samples would be appreciated!

 

[Grendel]

that1guy -- check Physical Limits in Digital Photography and Lens Diffraction & Photography.

Just know your camera limits and choose your settings wisely

 

[Woody]

Hey Woody,
I really would be interested in reading more, and seeing more comparisons on diffraction. Everything I have read and seen says that it gets worse on dense sensors, but this is one of those things where I would love to be proven wrong. It would make my life better, especially since it seems sensors are getting packed tighter and tighter these days Any info, links and photo samples would be appreciated!

I have tested this before but did not keep the photos. Will do so again. Give me some time.

 

[that1guy]

Sounds awesome, thanks for the info you two. Grendel, I will check out the links, Woody, I will check back for your photos. Thanks again

 

[lol]

Getting fed up of the endless speculation on diffraction limiting without basis, I actually went and did a practical test on the 50D before the 7D was available. More on it here.

Thinking more, I overlooked one factor in that test... as I was relatively close the magnification should start to contribute:
effective_aperture = physical_aperture * (1+magnification)
While I'm not 100% sure on the physics, the effective aperture value seems to impact the diffraction softening as opposed to the physical aperture value. Only something that becomes significant as the magnification increases so not something you would normally encounter.

 

[wuschba]

Wasn't today another possible "announcing-day" for the 60D?! Anything happening?

 

[visceralpsyche]

First spy photos are out:

http://bbs.kakaku.com/bbs/00490111139/SortID=11748888/ImageID=709823/

Looks like a significant change on the 50D!

HTH!

 

[match14]

Looks like a dissapointment then if these pictures are real.

Things missing that are on 50D are :-

C1 and C2 on the mode dial only C now

No picture style button

No multi controller for af point selection

Looks like most of these are to be done via the Q menu

Also buttons appear to be scattered around a bit.

 

[visceralpsyche]

No multi controller for af point selection

It looks like the back wheel has a smaller inner ring that might be the multi-controller and an outer ring which behaves like current generation bodies.

 

[match14]

Ah never saw that. Also looks like a push button in the center of the mode dial.

 

[gkreis]

Do you feel like you can rely on 3200? From the test shots I have seen in reviews, the noise begins to climb on that sensor quicker after 800 than I have seen with the 40D, 30D...

NOT true according to the RAW files here:
http://pixinfo.com/cikkek/dslr_evolution.3
with everything upscaled to 40 MP.

The 18 MP 7D/550D sensor trashes ALL older APS-C sensors from low to high ISO. That's why Nikon is going to release a 16 MP D90 update soon.

Even when the 7D RAW files are compared to the 1Ds3:
http://www.juzaphoto.com/eng/articles/canon_7d_review.htm

"Surprisingly, the 7D is relatively good in this aspect. It is not as good as the 1DsIII, but the difference is small - I'd say about 0.5 stop - and it is a bit better than the 500D and 50D."

"The 7D seems to capture slightly more detail into highlights (even though it shows a slight magenta cast), while the 1DsIII captures a bit more detail in the shadows - but the differences are so small that in practice you won't see any real difference."

I guess this pixel density myth won't die till the 16 MP Nikon D95 is released.

Wrong. This idea doesn't take into account the inherent noise in the technology.

http://www.clarkvision.com/imagedetail/does.pixel.size.matter/#Depth_of_Field_Myth

People like to point to photos that show the 7D doing just fine, BUT that is in well lit scenes. When the light begins to drop -- when some of us photographers like to shoot or are forced to shoot -- the 7D's small pixels are a problem. There is no substitute for larger pixels, period, if you are looking for better dynamic range and reduced noise. In the link above he explores the ideal pixel size (too few hurts images and too small hurts). The 7D and 50D crossed the line for the APS-C. I think a 13-14 megapixel APS-C is the sweet spot. Nikon, if the rumors are true, is being dragged into this pixel war that is not helping us folks.

 

[lol]

Skimming through the clarkvision link, the author of that suggests 5 micron pixel spacing (I work that out to be around 13MP for crop sensor) is his optimum preference on the basis of a diffraction limited f/8 lens. If you pick a lower aperture as limit, then it would shift the peaks in the chart to smaller pixel pitch. Yes, it does mean if you use higher aperture values you wont get the maximum resolution possible from the sensor, but you wont get any less than if you had a low resolution sensor either. See also my earlier link where I did a practical example of diffraction effects. You don't need to fear the onset of diffraction softening. The author also appears to be targeting optimal pixel sharpness. That's a common failing of the low MP fan group who fail to see the bigger picture.

In practice, I'm often shooting in poor light and the Canon 7D is the best >1.5x crop sensor camera I have ever used particularly at high ISO, and it also beats two bigger sensor cameras I've owned too.

 

[mushin]

Not only that, but his example at the end of the article to "prove his point" really destroyed his credibility for me. One, you can't prove anything with an example (although you can certainly disprove something by providing a counter-example.) Two, he "shows" that photo-stacking to reduce noise doesn't work, when people have been successfully using that technique for quite a while (just go take a look at astrophotography sites.) In the end, all the example does is show that he doesn't know how to utilize the technique, he doesn't fully understand what he's talking about, or both.