# Canon 5D mk III native ISO vs Expanded



## gshocked (May 26, 2014)

Hi all,

Is there a benefit in using the expanded ISO range vs the Native ones?
What do you use?

Thanks


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## Khalai (May 28, 2014)

gshocked said:


> Hi all,
> 
> Is there a benefit in using the expanded ISO range vs the Native ones?
> What do you use?
> ...



Expanded means digitally amplified (=heap of noise). It's basicly as if you exposed the shot on the highest ISO in the native range with -1EV(-2EV,...) exposure compensation and then (e.g in the Lightroom) just use exposure slider in the software to counter it. I personally, never use expansion. It's mostly only as last resort (make a shot or lose job scenario?...) or marketing gimmick.


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## gshocked (May 29, 2014)

Hi all,

Is there a way of turning off the expanded ISOs on a canon 5d mk III?


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## climber (May 29, 2014)

gshocked said:


> Hi all,
> 
> Is there a way of turning off the expanded ISOs on a canon 5d mk III?



Under ISO speed settings you can set "Auto ISO range" however you want. Let say from 100 to 12800.

If you don't use "Auto ISO", you set it by your decision anyway.

Was that helpful?


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## rs (May 29, 2014)

Page 128 of the manual should make things clear:

http://www.usa.canon.com/cusa/consumer/products/cameras/slr_cameras/eos_5d_mark_iii#BrochuresAndManuals

[quote author="Canon"]
You can set the manually-settable ISO speed range (minimum and maximum limits). You can set the minimum limit within L (ISO 50) to H1 (ISO 51200), and the maximum limit within ISO 100 to H2 (ISO 102400).
[/quote]


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## Don Haines (May 29, 2014)

gshocked said:


> Hi all,
> 
> Is there a benefit in using the expanded ISO range vs the Native ones?
> What do you use?
> ...


It allows you take bad pictures in bad light....

If you are going to resample the pictures down to "web size", you can still get reasonable quality....


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## mackguyver (May 29, 2014)

Are we talking about expanded as in the 2 highest ISOs or expanded as in the 1/3 stop pushed or pulled ISOs? 

The two highest ISOs can be turned on or off as rs posted and are all but useless given the noise levels. 

The 1/3 stop ISOs can be disabled by not using auto ISO and by setting ISO to 1 stop vs. 1/3 stop. The 1/3 stop ISOs are slightly pushed or pulled which compressed the DR just a bit, but in practical use I've never noticed anything that would preclude me from using auto ISO. 

For landscapes and other subjects that I carefully compose, however, I have my camera set to full stops and only use multiples of ISO 100. That's what I do, but keep in mind that I only shoot stills. The video guys have a whole other world when it comes to ISOs and I'm sure they'll weigh in here.


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## drmikeinpdx (May 29, 2014)

I sometimes use ISO 50 when I want to use a larger aperture and I can't increase the shutter speed due to flash synch limits. Seems to work fine, I don't notice any loss in quality.


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## rpt (May 29, 2014)

drmikeinpdx said:


> I sometimes use ISO 50 when I want to use a larger aperture and I can't increase the shutter speed due to flash synch limits. Seems to work fine, I don't notice any loss in quality.


They are talking about the higher end - 51k and 102k ISO...


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## Marsu42 (May 29, 2014)

Bottem line: iso expansion is only good for jpeg or video, for raw just use the highest analog iso and underexpose.



Khalai said:


> I personally, never use expansion.



Fyi: Even 12800 is only digitally amplified, the highest analog setting on 5d3 is 6400 and on 6d 3200 with 6400 being already very much on the digital side. See the Magic Lantern forum, they recently researched a lot about the various amplification stages esp. on 5d3 to gain more dynamic range and reduce noise.



drmikeinpdx said:


> I sometimes use ISO 50 when I want to use a larger aperture and I can't increase the shutter speed due to flash synch limits. Seems to work fine, I don't notice any loss in quality.



Note that there is no native iso 50 with Canon, it just cuts away dynamic range. Handy for not screwing on a nd filter in some situations when you've already got the fastest shutter, but then again it's only 1 stop so most likely it won't be enough.


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## DKN (May 29, 2014)

Fyi: Even 12800 is only digitally amplified, the highest analog setting on 5d3 is 6400 and on 6d 3200 with 6400 being already very much on the digital side. See the Magic Lantern forum, they recently researched a lot about the various amplification stages esp. on 5d3 to gain more dynamic range and reduce noise.


Very interesting! Do you have any source I could study on the subject?


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## Marsu42 (May 29, 2014)

DKN said:


> Very interesting! Do you have any source I could study on the subject?



Marsu42's internet search service responds immediately: http://www.magiclantern.fm/forum/index.php?topic=10111.0


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## verysimplejason (May 29, 2014)

gshocked said:


> Hi all,
> 
> Is there a benefit in using the expanded ISO range vs the Native ones?
> What do you use?
> ...



I use 6D. It's better in high ISO.  Joking aside, I just use whatever exposure is needed and worry about noise later. Native ones should have a lower noise compared to expanded ISO range.


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## verysimplejason (May 29, 2014)

DKN said:


> Fyi: Even 12800 is only digitally amplified, the highest analog setting on 5d3 is 6400 and on 6d 3200 with 6400 being already very much on the digital side. See the Magic Lantern forum, they recently researched a lot about the various amplification stages esp. on 5d3 to gain more dynamic range and reduce noise.
> 
> 
> Very interesting! Do you have any source I could study on the subject?



6D, 3200 and 5D3, 6400? Are you really, really sure???


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## Marsu42 (May 29, 2014)

verysimplejason said:


> 6D, 3200 and 5D3, 6400? Are you really, really sure???



I'm really, really sure that I read this in the thread which I linked above  ... as a 6d owner, I was very surprised myself, but they figured out that other than 5d3 you cannot tweak iso 6400 on 6d for more dynamic range because it's essentially just 3200 pushed. I still often use 6400 because I think the "out of the box" iq is ok, but when in doubt I switch to 3200 with a tendency to underexposure.

Note (or read the thread) that "analog vs digital" is not as binary as it sounds, Canon has various different stages of analog amplifications for each iso setting which they only fine-tuned on 1dx. Properly tuned by ML on 6d/5d3, in-camera processing might be still preferable or at least equal to postprocessing.


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## chrysoberyl (May 29, 2014)

@Marsu42 'Note that there is no native iso 50 with Canon, it just cuts away dynamic range. Handy for not screwing on a nd filter in some situations when you've already got the fastest shutter, but then again it's only 1 stop so most likely it won't be enough.'

Is there further explanation of this somewhere?


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## mackguyver (May 29, 2014)

chrysoberyl said:


> @Marsu42 'Note that there is no native iso 50 with Canon, it just cuts away dynamic range. Handy for not screwing on a nd filter in some situations when you've already got the fastest shutter, but then again it's only 1 stop so most likely it won't be enough.'
> 
> Is there further explanation of this somewhere?


Yes, here: QuickGuide to EOS Custom Functions

"EOS-1D, 1Ds, and 5D models also have an option for an ISO 50-equivalent “L” setting. ISO 50 is useful for studio flash photography when you want to use a wider aperture. *Note, however, that there will be approximately one less stop of dynamic range in the highlights at ISO 50*, which is why this setting is normally locked-out. ISO 50 is also not available during video recording."


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## Marsu42 (May 29, 2014)

chrysoberyl said:


> Is there further explanation of this somewhere?



ML Forum  ? Look for feature requests for adding iso 50 on cameras that don't have from Canon, and the ML devs refusing it because a) they don't know how to do it and b) even if it just degrades your iq and is only valid as a last resort.


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## DKN (May 29, 2014)

Marsu42 said:


> DKN said:
> 
> 
> > Very interesting! Do you have any source I could study on the subject?
> ...



Thank you!!


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## gshocked (May 31, 2014)

Hi all,

I read somewhere that its best to stick to ISOs such as 100, 200, 400, 800, 1600, 3200...
and the not the ones in between as 125, 160...?

Is there any truth to this?

Thanks,


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## neuroanatomist (May 31, 2014)

gshocked said:


> Hi all,
> 
> I read somewhere that its best to stick to ISOs such as 100, 200, 400, 800, 1600, 3200...
> and the not the ones in between as 125, 160...?
> ...



Some truth. Rather, I'd say avoid the +1/3 'tweener' settings of ISO 125, 250, 500, 1000, etc., on bodies except the 1D X.


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## Marsu42 (May 31, 2014)

gshocked said:


> I read somewhere that its best to stick to ISOs such as 100, 200, 400, 800, 1600, 3200...
> and the not the ones in between as 125, 160...?



Some lower 160x-multiples have a very small dynamic range advantage, but nothing to write home about - but it was the research starting point for Magic Lantern's mini_iso module to provide a real +1/3 to +1/2 dr improvement on full stop isos. See the same link I provided above for information on this.


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