# 5DS - effective resolution in mraw and sraw



## Good24 (Feb 23, 2015)

maybe I missed it but can't find anything online that discusses the effective resolution of the 5Ds when shooting in mraw and sraw. i.e. something akin to the charts in this page:

http://www.learn.usa.canon.com/resources/articles/2011/eos_qt_small_raw_images_article.htmlp

if anyone's seen it or knows please put in a link. Thanks!


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## Zeidora (Feb 24, 2015)

*Re: 5DS - effective "resolution" -> image-size in mraw and sraw*

Call me a stickler, but I really don't understand why 50 MP vs. 21 MP is referred to as "resolution"; it is image size.
Resolution in optics is how well two adjacent points can be separated. That is a function of the optics, not the body/sensor. The sensor only records what the optics transmit. So the question becomes, can the optics resolve the small pixels of a sensor. Here then, the question is also about individual pixel size, not number of pixels = image size.

I guess this boat has left, and we need to learn to live with this muddle. A shame, though, and can lead to much confusion, and there is are perfectly good terms for what is really meant.

With respect to (optical) resolution on mRAW and sRAW, it is identical with a given lens. AFAIU, mRAW and sRAW only use the central portion of the sensor, but the same pixels (no binning). The simplest 2x2 binning would lead to file sizes of ~12.5 MP, and neither of the smaller RAWs is that small. By using the central area only, you may get more of the sweet spot of the lens, so can squeeze out a bit more true resolution compared to the periphery of the image area projected by the optics.


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## rs (Feb 24, 2015)

*Re: 5DS - effective "resolution" -> image-size in mraw and sraw*



Zeidora said:


> Call me a stickler, but I really don't understand why 50 MP vs. 21 MP is referred to as "resolution"; it is image size.
> Resolution in optics is how well two adjacent points can be separated. That is a function of the optics, not the body/sensor.


Yes, resolution in optics is a function of the optics, not the body/sensor. But this question related specifically to the resolution of the body at different settings, not the resoltuion of the optics. That is a function of sensor/output files, not the optics.

Ok, strictly speaking, resolution should be measured in a unit of measurable detail per unit of distance, eg lines/mm or pixel pitch. But for a known and constant sensor size (and RAW, M-RAW and S-RAW all utilise an identical area), MP is equally as good.

Good24, here are your answers: (courtesy of http://www.usa.canon.com/cusa/consumer/products/cameras/slr_cameras/eos_5ds#Specifications)

RAW: 50.3 MP (8688 x 5792)
M-RAW: 28.50 MP (6480 x 4320)
S-RAW: 12.40 MP (4320 x 2880)


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## Good24 (Feb 25, 2015)

rs said:


> Good24, here are your answers: (courtesy of http://www.usa.canon.com/cusa/consumer/products/cameras/slr_cameras/eos_5ds#Specifications)
> 
> RAW: 50.3 MP (8688 x 5792)
> M-RAW: 28.50 MP (6480 x 4320)
> S-RAW: 12.40 MP (4320 x 2880)



Thank you! (And yes, for the record, I used the word "resolution" only because that's what Canon used in the link in my OP.)

Interesting that the 5DS s-raw will be bigger than the 5D3 m-raw, and will be more than 4K. I wondered because to me the 5DS might be nice to have all those mp's sometimes ... but more often than not I wouldn't need it. Seems someone could shoot in s-raw and still have remarkable images (and more manageable file sizes) and just break out the full raw when needed. Of course if you're only using the full 50 mp rarely, might be hard to justify getting in the first place.


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## Valvebounce (Feb 25, 2015)

Hi Good24. 
I don't know if it still holds true but I recall that mRaw and sRaw used to only be able to PP in DPP, other software did not recognise them. Maybe with such large file sizes this has changed? 

Cheers, Graham. 



Good24 said:


> rs said:
> 
> 
> > Good24, here are your answers: (courtesy of http://www.usa.canon.com/cusa/consumer/products/cameras/slr_cameras/eos_5ds#Specifications)
> ...


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## rs (Feb 25, 2015)

Valvebounce said:


> I don't know if it still holds true but I recall that mRaw and sRaw used to only be able to PP in DPP, other software did not recognise them.


Out of curiousity, I gave it a go with my 5D2 in M-RAW. LR opens it fine, so with a bit of luck the same will hold true of the 5Ds. I have CC, so I am using the latest version of LR.


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## Sporgon (Feb 25, 2015)

*Re: 5DS - effective "resolution" -> image-size in mraw and sraw*



Zeidora said:


> AFAIU, mRAW and sRAW only use the central portion of the sensor, but the same pixels (no binning).



:

And you're concerned with lens optics and pixels being muddled ?


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## adventureous (Mar 12, 2015)

Maybe it's just my lightroom, but the last time I tried editing a mRAW or sRAW it was just like editing a jpeg. Muddy.


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## 9VIII (Mar 12, 2015)

*Re: 5DS - effective "resolution" -> image-size in mraw and sraw*



Zeidora said:


> ...AFAIU, mRAW and sRAW only use the central portion of the sensor...



I would love to see where you got this information.


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