Canon announces development of the EOS R5 full-frame mirrorless camera

Michael Clark

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Thanks for sharing. Confirms what I was saying.

You said:

"However, if you do magnify in front of the aperture then the t-stop is quite different from the f-stop value. While that can be the case for a zoom at some focal length, it makes no sense for a prime.
Proof: Check f-stop and t-stop values for various primes and you will see they are very close (and the reason why t-stop value is always a bit worse than f-stop value, is the loss of transmission through glass). "


I just showed that there's no difference between zooms and primes in this respect.

Please tell me again how that confirms what you were saying?
 
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Michael Clark

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I believe it was either Craig himself orcanonnews guy who said it's a line (X). Sort of how OSX isn't a particular build but a group of builds. I never got more detail but it's somewhere here. I could search and dig....It's not really a big deal though, I think more time needs to be spent on pixel well talk and cripple nomenclature.

Yeah, I remember seeing the same thing, but I can't remember where either. Getting old stinks!
 
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joestopper

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Feb 4, 2020
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Writing 8k video (8192 x 4320 px = 35 MP) at 30fps would be
no fun if video terminated after a second or so, Sony overheat style.

30fps x 35 MP is 1050 MP/sec.

20fps x 45 MP is 900 MP/sec

There is no reason to think that the R5 will be able to handle
1050 MP/sec throughput sustained for some time, but not
900 MP/sec.

Knowing the way Canon operates, it is safe to assume that they have solved the heat issue allowing for sustained 8k recording. Canon did have a heat issue problem: That is the reason we have not seen IBIS earlier, even though they had patents on it years ago.
 
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joestopper

Rrr...
Feb 4, 2020
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You said:

"However, if you do magnify in front of the aperture then the t-stop is quite different from the f-stop value. While that can be the case for a zoom at some focal length, it makes no sense for a prime.
Proof: Check f-stop and t-stop values for various primes and you will see they are very close (and the reason why t-stop value is always a bit worse than f-stop value, is the loss of transmission through glass). "


I just showed that there's no difference between zooms and primes in this respect.

Please tell me again how that confirms what you were saying?


And I have shown you for both primes and zooms each an example in regard to front lens element size to aperture diameter and the resulting f-stop, t-stop relationship (and I am not repeating this again).
All these statements were confirmed by the charts you showed.
 
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Trankilstef

Image making loverEOS R and EOS R5 (soon)
Jan 5, 2020
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Also,

The implementation of the ON/OFF & also the MODE button is too bad on the EOS R
. (the same looks to have been copied for the R5) . To change video modes on EOS R you have to press the INFO button & then keep rotating the mode dial & keep looking into the top LCD till your desired MODE pops in…way too cumbersome & non-intuitive than the 5D4 which has a nice flip switch to move between photo/video.

Also, the INSTANT VIDEO (red record button) on top panel is actually a joke because…
say you are taking a photo in Av mode at 1/2000 sec at f2 & instantaneously you want to record video of that…so who the hell in the world would start recording the video instantaneously at 1/2000 of a sec??? One will go to manual video mode & change shutter speed to 1/50 or 1/60 as the case maybe & then to compensate reduce the Aperture, ISO. So it’s wrong to call this RED BUTTON as INSTANT Video!! Because it is NOT.

Actually you can just change mode very quickly by pressing the Mode button then tap directly on the screen to choose the mode you want to go in.

The instant video button doesn't act like you implies. It actually record straight video with the settings you saved on the C3video user preset. So you will probably save settings as Manual exposure - 24p - 1/50 - iso 400 - C-Log for example and everytime yoy press that button even though you're in Av mode with very high shutter speed it will overwrite this and use your C3 video setting.
 
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The general assumption is that at 8K30 the camera's processor would not be able to compress anything, so the output would be uncompressed raw. With video, buffer size is more or less irrelevant - the camera must be able to write to the card at least as fast as the data rate of the video.
That is not a safe assumption, though it seems more likely than not. It is complicated.

The camera might do 'computationally easy' compression, and in fact that might be easier than trying to write at full size.
We've seen data rates reduced down from 4-4-4 to something less used make it manageable.
If it can be included, dedicated hardware compresses orders of magnitude more easily than the normal processor.
The stars could have aligned to get a hardware compression unit into digic that's data rate limited vs frame resolution limited so it could manage 8k at this lower frame rate. If video chip team had a compression unit already taped out with a low enough power/chip die area/heat budget to include with the stills digic this generation. And the marketing team would have needed to allow its inclusion vs withholding it as an upgrade for the next camera, perhaps to drive adoption of the new mount.
 
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tron

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Where is the fast way to change fps on a 5D Mark IV/III? Or are you talking about changing Drive Mode from 'Single' to 'Continuous'?
yes! That was what I meant

EDIT: Which reminded me of a question I have about 90D. Is it possible to alter via customization the number of fps just like we can in 7DII? On 7DII I have set high to 8. It is high enough and at the same time saves buffer space for increased continuous use.

I have searched 90D's manual but I could not find this info so probably it does not have this customization.
 
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tron

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Nov 8, 2011
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If you could control off camera flashes and have an eye level viewfinder at the same time I'g get one.
Yes the eye-level viewfinder would be more comfortable for general use and would allow flash at the same time. That and allowing the use of GP-E2 (or connection to camera connect and use of gps through it just like EOS R and 200D).
 
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SecureGSM

2 x 5D IV
Feb 26, 2017
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Since we haven't seen the camera in action, there is no guarantee at this point that the autofocus will be fast and accurate. In comparison to DSLRs, the R is not fast and accurate when it comes to shooting action. I hope the R5 is, but it's best to wait and see. (And please, people, don't waste time posting pictures of an action shot that you got with the R. You can get good action shots with the R, but it's simply not up to DSLR standards.)
Yes, R struggled with sensor readout a lot. There seems to be quite a dramatic change in that department with R5. Faster readout = less EVF latency. So there is a hope :)
 
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AlanF

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yes! That was what I meant

EDIT: Which reminded me of a question I have about 90D. Is it possible to alter via customization the number of fps just like we can in 7DII? On 7DII I have set high to 8. It is high enough and at the same time saves buffer space for increased continuous use.

I have searched 90D's manual but I could not find this info so probably it does not have this customization.
I have just hunted through the camera menus and couldn't find customization of fps other than high or low speed.
 
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AlanF

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Thanks for the info. I was afraid so. Lowering down to 8fps would help with the buffer.
It's not a disaster filling the buffer on the 90D because it doesn't shut down the camera as it clears and it does continue shooting in fits and starts as the buffer clears, unlike the 5DSR for example. You get 2-3 secs of burst of RAW at 10 fps, then a fraction of a second pause, then another couple of shots and so on. I haven't been limited by the burst so far the way I shoot.
 
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Michael Clark

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Apr 5, 2016
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And I have shown you for both primes and zooms each an example in regard to front lens element size to aperture diameter and the resulting f-stop, t-stop relationship (and I am not repeating this again).
All these statements were confirmed by the charts you showed.

You've shown me nothing to prove your assertion that the front of a lens diameter will always be equal to or greater than the size of the entrance pupil.
Just because some or even many lenses have front elements that are equal to or larger than the entrance pupil does not mean that they all must be.

All you've shown me is that you deny saying what you've previously said.

You claimed that prime lenses have T-stops closer to the f-number than zoom lenses. I showed that to not be true. There are many prime lenses with T-stops about one-third to one-half stop slower than their f-number, just as there are many zoom lenses with T-stop values about one-third to one-half stops slower than their f-number, just as I showed that there are both primes and zooms with T-stop values very close to their nominal f-number.

You claimed that no prime lenses do magnification between the physical aperture diaphragm and the front of the lens. I showed you that the only way that is possible is if there is no glass or only a flat plate between the aperture diaphragm and the front of the lens. If there is any refractive surface with an index other than 1.00 in front of the aperture diaphragm, then there is either positive or negative magnification occuring.

You claimed that as the magnification between the aperture diaphragm and the front of the lens increases, the difference between the f-number and T-stop must increase. I showed that there are many zoom lenses which maintain the same T-stop throughout their zoom range.
 
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Michael Clark

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Apr 5, 2016
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yes! That was what I meant

EDIT: Which reminded me of a question I have about 90D. Is it possible to alter via customization the number of fps just like we can in 7DII? On 7DII I have set high to 8. It is high enough and at the same time saves buffer space for increased continuous use.

I have searched 90D's manual but I could not find this info so probably it does not have this customization.

The 90D does not have user selectable frame rates for High speed and low speed continuous shooting. Neither do the 5-Series cameras. Other than the 1-Series the 7D Mark II is the only other model I know of that has this.

The 90D also does not allow the user to select maximum and minimum Tv and Av like the 7D Mark II does.
 
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unfocused

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The 90D does not have user selectable frame rates for High speed and low speed continuous shooting. Neither do the 5-Series cameras. Other than the 1-Series the 7D Mark II is the only other model I know of that has this.

The 90D also does not allow the user to select maximum and minimum Tv and Av like the 7D Mark II does.
More reasons to miss the 7DII.
 
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Michael Clark

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More reasons to miss the 7DII.

I'm still using one. Will probably buy another before they're all gone.

The 90D is a better general purpose camera than the 7D Mark II. But I've got 5-series cameras for general purpose work.

I use the 7D Mark II to shoot field sports under artificial lighting with telephoto lenses. For that purpose it's still a better camera, in my opinion, than the 90D, though each does have advantages over the other for that role. I choose the 7D Mark II for the longer shutter rating, the better build, and the better AF system.
 
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unfocused

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I'm still using one. Will probably buy another before they're all gone.

The 90D is a better general purpose camera than the 7D Mark II. But I've got 5-series cameras for general purpose work.

I use the 7D Mark II to shoot field sports under artificial lighting with telephoto lenses. For that purpose it's still a better camera, in my opinion, than the 90D, though each does have advantages over the other for that role. I choose the 7D Mark II for the longer shutter rating, the better build, and the better AF system.
Yeah, I have a feeling that the 7DII is going to hold its current value for awhile. Similar to the 1D IV -- which only recently dropped in value on the used market.
 
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