Why are full frame mirrorless images smaller than DSLR images?

neuroanatomist

I post too Much on Here!!
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Jul 21, 2010
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The 5DIV has a 30 MP sensor, the R6 has a 20 MP sensor. Why would the images from the R6 not be smaller?

Perhaps you should clarify what you mean by '~17% smaller'.
 

Nemorino

EOS R5
Aug 29, 2020
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Have you taken the pictures at the same time? The distance moon earth changes and the moon sometimes apears larger.
 

Nemorino

EOS R5
Aug 29, 2020
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OK. It changes but not that fast. :ROFLMAO:

Do you use DPP or LR? Maybe the lens corrections are turned on?

Afaik the R6 has the same sensor as the 1dXmkIII. Only the R3 and R5 have new ones.
 

dcm

It's not the gear. But it helps.
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Apr 18, 2013
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I assume you are looking at them with the same magnification. If you use 1-1 (pixel peeping), then the difference in megapixels is what you are seeing. If you are viewing the images with fit to screen, then the framing should roughly be the same.
 
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I assume you are looking at them with the same magnification. If you use 1-1 (pixel peeping), then the difference in megapixels is what you are seeing. If you are viewing the images with fit to screen, then the framing should roughly be the same.
Please elaborate - you're saying 100% magnification is 87% magnification with R6 images?
 

neuroanatomist

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Please elaborate - you're saying 100% magnification is 87% magnification with R6 images?
Imagine you have an 8K monitor, meaning a ~33 MP display. An image from your 5DIV at 1:1 would nearly fill the screen. The same image from your R6 at 1:1 would not nearly fill the screen, so the image displayed will look smaller. The same is true at 1:1 on a lower resolution display, but you only see part of the image.
 

jd7

EOS R
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Feb 3, 2013
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Please elaborate - you're saying 100% magnification is 87% magnification with R6 images?
Essentially, yes (although I haven't done the maths to check the difference is 17%).

When you view an image at 100% magnification on your screen, a pixel in the image is displayed at the same size regardless of whether you started with a 20MP image (R6) or a 30MP image (5DIV). Therefore, if you have more pixels in an image, the size of the image is bigger on your screen simply because there are more pixels (of the same size) being displayed.

When you view the images so both fit your screen, the image with more pixels is being downsampled more.

However, in either case, the relative size of the elements in the images will remain the same, ie in your case, the moon should take up the same proportion of the image regardless of whether you are looking at the 20MP image or the 30MP image.