Review: Canon EOS R by DPReview

Joules

EOS 80D
Jul 16, 2017
158
78
Hamburg, Germany
I'm sorry if it seemed like I was accusing you of something or if I formulated my post to confusingly. I just wanted to present my understanding of the reach advantage of higher pixel density bodies so that somebody could point out a flaw in it if it exists.
First, I do not believe the Sigma lens you are talking about is available for M4/3. [...] But we were not speaking about lenses.
I only brought up the sigma zoom to show why I'm curious about the subject. But lets ignore that, I'm really just curious about the theory. It's what I find the most interesting about the CR forum.

Things like the formula for spatial resolution that was mentioned in another threat here just don't come up in the kind of YouTube Videos I watch, for example.

And you are right that theory has its limits, but it also has its value. For example, I used to believe that the act of raising the ISO itself is the source of noise that appears when working with low light, until I read into Signal to Noise ratio.
Why you want to throw the Canon 600MM f/4L into this discussion at all makes no sense to me. I could also add a 2X tele converter to a 400mm lens and get 800mm on FF, or it would "behave" like a 1,280mm on your 80D. So tell me how crop is an advantage again? When all I need is one of Canon's superb tele converters?
Let me try to put my example differently:

A FF und m4/3 Body stand in the same Position an have the same 300mm 4.0 lens attached. The FF body will have a wider FoV. To match the crop Bodies FoV there are three options:

- Crop the image in half horizontally and vertically. By doing this, 75% of the gathered signal and resolution is discarded, raising the Signal to Noise Ratio to the same value as the Crop body (Assuming similar sensor technology) .
- Use a 2X Teleconverter. By doing this, the Signal is also reduced by 75%. The sensor resolution is maintained though. Total resolution will still be affected by the quality degradation in the lens + TC system.
- Use a lens with 600mm focal length. If the current aperture is to be maintained to maintain the amount of Signal this requires the purchase of the 600mm 4.0.

Obviously the first option has no additional weight or cost. Once cropped to the same FoV, the images from both cameras should be equal if their pixel density is equal. Otherwise, the body with higher density (Which today would most likely be the crop body) should have the advantage when the output size is big enough to show the difference in detail.

The second option is the same, except now no cropping is involved and total amount of pixels can be compared instead of pixel density. Oh, and it adds a bit of weight and cost to the FF system.

The third is optically the best, as no signal and no resolution are lost for the FF System, giving it a 2 stop advantage over the crop system in terms of gathered signal. However, the price increase will rule this option out for many.

Does that make it clearer what I was trying to say? I'm not Considering the 300mm or 600mm as lenses to buy, I just used them to make the point that the term reach advantage could be meaningfull.

Second, my argument was not that I could use a "better" lens to avoid cropping. That is not what I said or implied at all.
In your example you compared a 30mm lens on the m4/3 body to a 60mm on the FF body. I understand that as "To match the FoV between bodies of different sensor size, use greater Focal lengths on the body with the greater sensor size". So I used an example where this is more or less impossible due to price constraints to show how the term reach advantage could make sense.
Third, low light performance and noise are absolutely not the same.
Okay, I wrote noise in the last post when I should have used signal to noise ratio. Which should be the same as what you call low light Performance.
Fourth, if sensor size doesn't make a difference then why not just use an iPhone[...].
Sensor size makes a difference. A larger sensor captures more signal if all other factors (Exposure time, f-number, lightsource) are equal. However, this signal gets reduced when you crop, so the output of a larger sensor should become equal to the one from a smaller sensor if cropped to the samw size. At that point, given similar sensor tecchnologies only the remaining resolution should determine image quality. Am I wrong?
In the end we have to choose for ourselves. However, saying or implying that a M4/3 sensor on an Olympus will resolve as well as an 80mp FF sensor in any possible situation is absurd. Ridiculous. (dak723)
I think all dak723 said that to match a 20MP m4/3 sensor's pixel density you would need an 80MP Full Frame sensor. Which is true. Obviously the Full Frame sensor is now equal or better than the smaller sensor in any situation in terms of image quality.
 
Reactions: CanonFanBoy

4fun

picture? perfect!
Nov 19, 2018
181
53
@Joules

mFT sensor diagonal is 21.6mm, FF is 43.27mm -> factor 2 for diagonal FOV
mFT sensor area is about 225 mm2, FF is 864 mm2 -> factor 3.84, close to 4

Looking at spatial resolution / matching pixel density or "pixels on target" for FF vs. mFT factor 4 (or 3.84) applies

But ... FF sensor area collects 3.84x more light than mFT = about +2 stops -> better S/N ratio. Not having done any such comparison myself, I believe some of that advantage (not all of it) will also be present at the pixel level and would expect a cropped image from a good, current 40-50MP FF sensor eg Canon 5Ds/R or Nikon D850, Sony A7R III to (technically) match any 20 MP mFT image.

For full equivalence (= including DOF) factor 4 (3.84) applies. So equivalence for a 600/4.0 FF lens would require a (non-existing) mFT 300/2.0 lens, not a 300/4.0 ... or other way round, a 300/4.0 mFT lens is equivalent to a 600/8.0 FF lens.

In my view, mFT has (about) 25% of FF sensor area, and 25% "technical capability". But unfortunately size/weight/price of mFT gear is more than 50%, often closer to 75% of [equivalent] FF gear. Currently best ratio/most "bang for the buck" is APS-C, especially EOS M/EF-M.
 
Reactions: Joules

Ian_of_glos

EOS RP
Jun 12, 2012
236
20
England
1. "sports photography" ... a very wide field. So many sports. Outdoor/Field vs. indoor. Table tennis in poorly lit indoor venues is one challenge, a basketball court another one, a large soccer/football/baseball stadium another one, track&field outdoors, snow sports, swimming, car racing, .... all different needs. Only some sports require use of big long [white :)] tele lenses.

2. Unfortunately size, weight and price of mFT gear do not scale well with sensor size. mFT sensor surface is only about a quarter of FF, but "pro"-grade mFT lenses are almost as big, fat, heavy and expensive.

For me mFT has therefore never been enticing. I rather go for a camera with larger sensor and lenses 1 or 2 stops slower, smaller, lighter, less expensive. f/4.0 FF zooms would require f/2.0 zooms on mFT for full equivalence. They would not be much smaller, lighter or less expensive.

3. With today's hi-rez FF sensors - 40, 50, + MP - the "reach advantage" of smaller sensors has become a "mere illusion".
Well the sport I photograph most often is rugby union. The action moves from one end of the pitch to the other very quickly so photographers are faced with a choice. Either:
1) stay in one place using a large DLSR system such as a Canon 1DX or Nikon D5 with a large telephoto lens such as a 500mm or 600mm F4 and accept that you are going to miss some of the action.
or
2) choose a lighter and more mobile set up.
Running up and down the touchline carrying a 1DX and 500mm F4 lens is not for the faint hearted and then you also need a second camera for the close up shots, so in recent years I have started using a Canon 100-400 F4.5-5.6. On a bright sunny day in September this works perfectly, but at this time of year F5.6 is juts too slow. From half time onwards I have to resort to ISO of 51,200 or even higher in order to obtain a fast enough shutter speed and needless to say the results are not good.
I would dearly love another option and the Olympus 300mm F4 looks like an attractive possibility. Combined with an OM-D E-M1 Mark II it would give me a burst rate of 15fps, weather sealing and an additional stop of light. However, before I go out and buy one, please would you explain what are the negative aspects of this system?
 

Joules

EOS 80D
Jul 16, 2017
158
78
Hamburg, Germany
I would dearly love another option and the Olympus 300mm F4 looks like an attractive possibility. Combined with an OM-D E-M1 Mark II it would give me a burst rate of 15fps, weather sealing and an additional stop of light. However, before I go out and buy one, please would you explain what are the negative aspects of this system?
The downside is the sensor size. Even though at f4 the 300mm Olympus lens on its own yields twice the amount of light per area compared to a f5.6 lens, the sensor's small area means that the total amount of light gathered is still less than that of a Full Frame camera and lens combination.

An APS-C Sensor captures ~1.45 times as much light than a Four Thirds one, and a full frame sensor captures 3.84 times as much light as Four Thirds. So, to see an actual improvement in Signal to Noise ratio, you'd need to use a lens with a two stop advantage on the Four Thirds camera.

However if you use your 100-400mm on a Full Frame body, to match the 600mm equivalent Field of View you get by using a 300mm lens on a Four Thirds sensor you'd have to crop the pictures from it. And that should reduce the total gathered signal, resulting in an image where noise is more pronounced (Or magnified, if you want to think about it like that). If I'm right about that, to get to equal FoV the FF Image would require Cropping to 44.4% of the image ( (400 / 600)^2 = 0.667^2 = 0.444), reducing the Full Frame sensor's 3.84 times light gathering advantage to 1.71 times (0.444 * 3.84). Which is less than the stop of light advantage that the 300mm f4 has over the 400mm f5.6, but not much.

Take this with a big grain of salt, since its just my understanding of this and I haven't had the time to test it out much. I wanted to do some comparison of this concept with actual pictures last weekend, put didn't find the time. When I do and the results are worth showing I might post them in the forum.

Since 4fun says the Micro Four Thirds system's supposed advantage in a scenario like this isn't a thing anymore, maybe he or somebody else can also point out a mistake in my train of thought.
 

4fun

picture? perfect!
Nov 19, 2018
181
53
yes, I see calculation geometrically the same way for 400/5.6 FF vs. 300/4 mFT ... 3.84 < 4.
And if one really needs 4.1° diagonal angle of view [600mm FL on FF] ... and no zoom ... then mFT 300/4 is an alternative ... fully equivalent to a 600 / roughly f/7.8 lens on FF.
However I also believe FF system still has an advantage over mFT even with equivalent pixel density and pixel size sensors, as long as crop is taken (more or less) from center of image. In terms of sharpness/acuity and light transmission/less vignetting - amount depending on characteristics of lenses in comparison.
 

Ian_of_glos

EOS RP
Jun 12, 2012
236
20
England
The downside is the sensor size. Even though at f4 the 300mm Olympus lens on its own yields twice the amount of light per area compared to a f5.6 lens, the sensor's small area means that the total amount of light gathered is still less than that of a Full Frame camera and lens combination.

An APS-C Sensor captures ~1.45 times as much light than a Four Thirds one, and a full frame sensor captures 3.84 times as much light as Four Thirds. So, to see an actual improvement in Signal to Noise ratio, you'd need to use a lens with a two stop advantage on the Four Thirds camera.

However if you use your 100-400mm on a Full Frame body, to match the 600mm equivalent Field of View you get by using a 300mm lens on a Four Thirds sensor you'd have to crop the pictures from it. And that should reduce the total gathered signal, resulting in an image where noise is more pronounced (Or magnified, if you want to think about it like that). If I'm right about that, to get to equal FoV the FF Image would require Cropping to 44.4% of the image ( (400 / 600)^2 = 0.667^2 = 0.444), reducing the Full Frame sensor's 3.84 times light gathering advantage to 1.71 times (0.444 * 3.84). Which is less than the stop of light advantage that the 300mm f4 has over the 400mm f5.6, but not much.

Take this with a big grain of salt, since its just my understanding of this and I haven't had the time to test it out much. I wanted to do some comparison of this concept with actual pictures last weekend, put didn't find the time. When I do and the results are worth showing I might post them in the forum.

Since 4fun says the Micro Four Thirds system's supposed advantage in a scenario like this isn't a thing anymore, maybe he or somebody else can also point out a mistake in my train of thought.
Thank you for your detailed explanation. I think I would be willing to accept a loss of image quality in order to have a smaller and thus more mobile set up. Nobody really looks at the technical aspects of my pictures anyway. What is most important is to capture the moment and present the key moments from the match for people who were not able to be there.
I know at least one photographer who has switched from a Nikon full frame system to the Olympus and he is convinced that he made the right decision. However, I am still sitting on the fence and wondering whether I would regret the decision.
 

Michael Clark

Now we see through a glass, darkly...
Apr 5, 2016
581
254
My 2 cents asto why Canon doesn't include IBIS: Money.

IBIS = every lens now has stabilization. Works almost as well as in lens IS when shooting static subjects to stabilize the camera shake of the photographer. Does not stabilize as well when trying to stabilize a panning shot, such as a moving car.

In Lens = Heavier lens, but better sports and moving subject image stabilization options. If combined with IBIS you might achieve an extra 1/2 stop over either of them alone.


My theory on why Canon doesn't have it simply comes down to money. Canon charges a premium for IS and gets it. If they build in IS, they will lose quite a bit of people willing to pay a premium for IS on non sports lenses (the IS version of the 70-200 will probably still sell if used for sports, the hand held portrait shooter might opt to use IBIS and buy the lower cost version).

No one needs IS to shoot sports with a 70-200. The shutter speeds required for shooting sports are short enough that IS does not matter. Neither would IBIS. If you can't get a clean, blur free shot with a 200mm lens shooting at 1/800 or faster, you don't need to be shooting sports.

The reason the EF 70-200mm f/2.8 L IS II sold so well to sports shooters, in numbers the older EF 70-200mm f/2.8 L IS did not, is because it was also a sharper lens than the EF 70-200mm f/2.8 L or the EF 70-200mm f/2.8 L IS.
 
Oct 29, 2018
4
1
We're loving our EOS R. I think it's a blast to shoot with compared to our 5D mkIII and the colours over the Sony A7III which we also use, are much better in our preference. Here's a link to a video comparison we did between the 5D and the EOS R - if you want to see side by side comparisons (shot on 50mm 1.2, 85mm 1.2, and 135mm f2):

Link to Site Removed by Mod. Its primarily advertising.