Rumoured Canon EOS Rs Specifications [CR1]

Ozarker

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The issue with IBIS and cooling is three-fold, and only the smallest part of the problem (heat generated by the IBIS actuators) is resolved by simply turning IBIS off.

The two main issues that aren't resolved are related to thermal mass, and thermal path.

Firstly, to optimise IBIS you need to minimise the mass of your sensor assembly, otherwise the IBIS actuators have to be much larger/more powerful to move the sensor as effectively. If you minimise the mass of the sensor, you're also minimising the thermal mass (i.e. the size of the heatsink), so your sensor will (for the same energy consumption) get hotter faster.

Secondly, because IBIS by definition means the sensor has to be able to move in relation to the lens mount, it also means the thermal path between the sensor and the outside of the body is seriously compromised (in the absence of ducted or peltier cooling). With a traditional fixed sensor, you can have a solid high density thermal path allowing heat from the sensor to be conducted to the body, from where it can be shed by radiant heat loss. With IBIS, you have at best a thin flexible connector with much lower thermal conductivity between the sensor and body shell, so it's much harder to move the heat out.

It may not be an issue with your style of shooting, but thermal management is a serious design constraint.
Hmmmmm. I wonder if this is the reason for the heat transfer tape (heat sink) behind the bayonet mount on the RF lenses? It is not in EF lenses. See the teardown of the RF 50mm f/1.2L at lensrentals.
 
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dtaylor

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The laws of physics and diffraction are quite clear that you lose resolution as you go from wider to narrower aperture .

In a diffraction limited lens, yes. In an aberration limited lens you certainly can gain both resolution and sharpness by stopping down. I'm not sure if there are any diffraction limited lenses in 35mm format. Every one I can think of has an optimal aperture stopped down from wide open, even if just 1 stop. I know there are a few in MF.

Your eye balling shots from TDP doesn't get around those laws,

And your attempt to appeal to "laws of physics" to theoretically prove that X is better than Y is a straw man. I never said the 5Ds was sharper, nor did I say that it was exactly the same pixel-by-pixel. As I've said from the beginning: it can be difficult to find the sharpness differences while pixel peeping; would likely be impossible in print straight from camera; and would certainly be impossible after post processing.

To prove/disprove my claims scientifically...as opposed to the claim you want to debate...would require a double blind test with, say, 36" prints. In our last debate when I was arranging side-by-side crops from online test samples I had to redo a couple because I was moving fast, looked away for a second, and all of a sudden wasn't 100% confident I had moved the right crop to the right position in PS. This is viewing at 1:1 and 2:1 on a 4k monitor. I'm quite confident that it would not be possible to pick 5Ds from 5DsR prints at 36" or even 48" in a double blind test, all other factors being equal.

I believe I said in our last debate that my advice to people is: if you're OCD about sharpness get the 5DsR. If you're OCD about moire get the 5Ds. If you're not OCD choose based on your favorite badge color.

and the author of TDP disagrees with your conclusions about his images and concludes that the 5DSR picks up detail lost by the 5DS...I'm finding the real world differences to vary modestly, but the difference in fine details is generally very noticeable.."

I shouldn't have to point out the possibilities of operator error under field conditions, selection bias, or confirmation bias. If carefully performed lab tests show X but someone claims in the field that they get Y, it's most likely that they're not really getting Y. It's not impossible, but then if the difference is "big" or even "significant" and Y is regularly achieved outside of a lab...where is the avalanche of examples? And what is wrong with the lab?
 
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dtaylor

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Jul 26, 2011
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You are equating contrast and sharpening with resolution, but they are different. Edge sharpness can be improved by a variety of procedures, including USM, and, as Aussieshooter implies, that if edge sharpness is what is important to you, as in architecture and little cropping, then an AA-filter won't cause much problem. But, for resolution, details that are lost by blurring cannot be simply restored by sharpening. So, if you need pixel level resolution, which I often do, the AA-filter does lose detail and gets in the way.

True in general. But when we look at resolution charts for these specific cameras the 5DsR lines are aliasing at the same time that the 5Ds lines are blurring. Imaging Resource found the same "clean" resolution for both cameras for this reason. Unfortunately the cameras exceeded their ability to test for extinction resolution, so we don't have numbers from them that I can interpret as small and you can interpret as big :LOL: Or perhaps even find to be identical.
 
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AlanF

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For those who like measurements and are interested in sensor resolution and how it is affected by f-number and AA-filter, here is a graph from https://www.optyczne.pl/324.4-Test_aparatu-Canon_EOS_5Ds_Rozdzielczość.html

The resolution (MTF in line pairs/mm) decreases with increasing f-number and as the f-number goes through the diffraction limited aperture of f/6.7 for the 5DS and 5DSR, the difference between the two becomes less significant.
150711_C5Ds_rozdz_m.png
 
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I understand this point of view but let's pretend for a minute. If the competition didn't have it, would you demand Canon to have it ? In the past year I have seen 90% of the desire for Canon products to be keeping up with the Sony/Joneses...not asking for bodies and lenses for the sake of particular shooters needs.(meaning, they always mention Sony) I couldn't give a rats tuchus what systems which I am not invested in have features others are using. But that's just me I guess, everyone else is in the 'Play catch up Canon/Canon is doomed' race. Perhaps it's the Ebay culture of easily parting with and selling your goods (which I find to be a major PITA) for others that fuels the GAS and self deluded needs.

Could it be the understanding that digital imagery is in it's infancy and I'm still clinging to my film based curmudgeonly views where folks did just fine with much much less?

I don't need no stinking IBIS, the glass stabilization is more than fine, especially the new 4+ stops lenses.

I understand where you're coming from, and the short answer would be, if your current gear is working well for you, then no.

But, there's also the side that if a brand wants people to buy something new/extra, then they have to add something in there too; people who feel their gear isn't doing what they want, and are looking for an upgrade, will also often be looking at what might fit their needs. For some, being able to stablise primes with IS might be the feature that gets them buying something new.

I know when I was looking at upgrading from my old 6d, I was definitely looking at what other brands were offering, to see if they had what my situation needed. But, it also wasn't until I saw what other people were able to shoot/capture that I started to think the 6d wasn't actually fitting my needs - until then I'd more or less just assumed what I wanted to get were shots that weren't really possible

I think what canon should be considering is not everyone may be happy with what canon are offering in their current models, and needs to be enticing people with features that make them seem like a good option/value. Ibis is one of those things that is useful enough that people will only look at options with it - one family member herr hasn't bought a fuji XT-3, only duet to it's lack of ibis


Edit: above is just about ibis and canon adding/not adding features that sony/nikon etc may have - I'm not meaning that this camera won't appeal to anyone if it doesn't have ibis, just that some people may pass on it for what it lacks, rather than what it adds. I'm sure there'll be people where one particular feature isn't a priority
 
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Andy Westwood

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Very interesting spec, 75MP isn’t for me but I’m sure a high mega pixel camera will popular with many.

Although portrait photographers should be happy with the new improved eye auto focus I think the return of the joystick would be welcomed by many for fine pinpointing AF when shooting other subjects as the touch, or touch and drag can be a little fiddly for precise focus not needing face and eye AF.

I agree with the majority on here to lose the touch bar, I don’t use that, so it just takes up space on an already crowded body.

For shooting in landscape format the pull out M5 style screen is perfect as your subject is right in front of your lens, however when shooting in portrait format the articulating screen is wonderful especially for us righthanders, so for that reason I much prefer the articulating screen over the pull out screen.

I just wonder what Canon will do with the up and coming R version of the 1D series, I fear too many snapped screens for the hustle and bustle of journalists or busy sports events etc if they were using a screen that pivoted out past the protection of the camera body. I guess in situations such as those they would be best keeping the screen tucked into the back of the camera.

I think it’s an exciting time right now to be a Canon shooter, many might say it’s about time again given rise in Sony and other manufactures in recent years.
 
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Architect1776

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The issue with IBIS and cooling is three-fold, and only the smallest part of the problem (heat generated by the IBIS actuators) is resolved by simply turning IBIS off.

The two main issues that aren't resolved are related to thermal mass, and thermal path.

Firstly, to optimise IBIS you need to minimise the mass of your sensor assembly, otherwise the IBIS actuators have to be much larger/more powerful to move the sensor as effectively. If you minimise the mass of the sensor, you're also minimising the thermal mass (i.e. the size of the heatsink), so your sensor will (for the same energy consumption) get hotter faster.

Secondly, because IBIS by definition means the sensor has to be able to move in relation to the lens mount, it also means the thermal path between the sensor and the outside of the body is seriously compromised (in the absence of ducted or peltier cooling). With a traditional fixed sensor, you can have a solid high density thermal path allowing heat from the sensor to be conducted to the body, from where it can be shed by radiant heat loss. With IBIS, you have at best a thin flexible connector with much lower thermal conductivity between the sensor and body shell, so it's much harder to move the heat out.

It may not be an issue with your style of shooting, but thermal management is a serious design constraint.

So how does Sony and Nikon overcome this issue?
 
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Don Haines

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Jun 4, 2012
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The issue with IBIS and cooling is three-fold, and only the smallest part of the problem (heat generated by the IBIS actuators) is resolved by simply turning IBIS off.

The two main issues that aren't resolved are related to thermal mass, and thermal path.

Firstly, to optimise IBIS you need to minimise the mass of your sensor assembly, otherwise the IBIS actuators have to be much larger/more powerful to move the sensor as effectively. If you minimise the mass of the sensor, you're also minimising the thermal mass (i.e. the size of the heatsink), so your sensor will (for the same energy consumption) get hotter faster.

Secondly, because IBIS by definition means the sensor has to be able to move in relation to the lens mount, it also means the thermal path between the sensor and the outside of the body is seriously compromised (in the absence of ducted or peltier cooling). With a traditional fixed sensor, you can have a solid high density thermal path allowing heat from the sensor to be conducted to the body, from where it can be shed by radiant heat loss. With IBIS, you have at best a thin flexible connector with much lower thermal conductivity between the sensor and body shell, so it's much harder to move the heat out.

It may not be an issue with your style of shooting, but thermal management is a serious design constraint.
This is one of those places where the micro 4/3 cameras have the advantage. The sensor is a quarter of the size, and that means (approximately) a quarter of the mass and presumably, does not have to move as far....

Every design criteria has plusses and minuses
 
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Good for you, however Canon don't care for your thoughts as an individual so you might be waiting a very long time.
I think that the consumer will win here if they need to wait a very long time for IBIS from Canon because they can simply switch brands, so it would be very wise for Canon to listen to what it’s customers, including me would like to see in their cameras, and very soon...
 
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The issue with IBIS and cooling is three-fold, and only the smallest part of the problem (heat generated by the IBIS actuators) is resolved by simply turning IBIS off.

The two main issues that aren't resolved are related to thermal mass, and thermal path.

Firstly, to optimise IBIS you need to minimise the mass of your sensor assembly, otherwise the IBIS actuators have to be much larger/more powerful to move the sensor as effectively. If you minimise the mass of the sensor, you're also minimising the thermal mass (i.e. the size of the heatsink), so your sensor will (for the same energy consumption) get hotter faster.

Secondly, because IBIS by definition means the sensor has to be able to move in relation to the lens mount, it also means the thermal path between the sensor and the outside of the body is seriously compromised (in the absence of ducted or peltier cooling). With a traditional fixed sensor, you can have a solid high density thermal path allowing heat from the sensor to be conducted to the body, from where it can be shed by radiant heat loss. With IBIS, you have at best a thin flexible connector with much lower thermal conductivity between the sensor and body shell, so it's much harder to move the heat out.

It may not be an issue with your style of shooting, but thermal management is a serious design constraint.

Fantastic and succinct explanation. Thanks.
 
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Jan 29, 2011
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I think that the consumer will win here if they need to wait a very long time for IBIS from Canon because they can simply switch brands, so it would be very wise for Canon to listen to what it’s customers, including me would like to see in their cameras, and very soon...
Market analysis and hard data will win, Canon spend millions of dollars a year on both, they will release IBIS if and when they project it is financially advantageous for them to do it. Several anonymous forum posters, even if they numbered in the dozens, amount to less than a mosquito bite on an elephant and are neither authoritative nor have a value from an accurate market analysis point of view.
 
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So how does Sony and Nikon overcome this issue?

Almost every manufacturer has some form of IBIS. Even Fuji has IBIS on its GFX 100 (although the body is substantially larger). But FF Sony bodies are about the smallest, and none of the current models overheat while recording 4K video with IBIS on. I think most companies have already figured out how to implement this properly, but Canon, not yet having a FF body with IBIS will have to start somewhere if they haven't already.
 
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cayenne

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Thank you. Topics such as firearms are not welcome here, it is a gateway drug to yammering on about religion and politics.


It was more of a joke, in that it was a reference to the last scenes in the old Clint Eastwood spaghetti western, a Fist Full of Dollars....where he with his .45 does against the villain with a winchester...you know, the scene where Clint taunts him to 'aim for the heart' or you'll never stop me....keeps getting shot but keeps getting back up, and then when the villain is out of ammo, Clint opens his poncho and reveals a steel iron plate he'd hammered out and had hanging over his chest to protect him?

Maybe I'm getting old....but did no one else get the reference?
 
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