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Tai
14-08-2012, 1:47pm
I am new to photography and have just finished doing my first ever grey scale test to figure out the dynamic range of my camera when I had a thought.

Would the dynamic range of my camera change if I increased the ISO? :rolleyes:

I have a Canon 5D mark II and after completing my grey scale test I found that the dynamic range of my camera was 11.

But would this stay the same if I increased the ISO from 100 to a higher setting maybe to 400 or 800?

I would go out and redo the test again and I plan to but it is raining very heavily today so I thought I would post on here and see what everyone else thinks of this question while I wait for a better day to go outside.

So can anyone tell me would the dynamic range change if I increased it?

If I had to guess I would say the lower the ISO is the higher DR and the higher the ISO is the lowers the DR? :confused013

Maybe? I'm just guessing and I'm sure you can all give me a much better answer to this question that me just guessing.

THANKS! :D

ricktas
14-08-2012, 1:52pm
No. The dynamic range of your sensor is set. It is the number of f/stops that your camera sensor can effectively capture in one photo, changing the ISO changes the sensitivty of the sensor to light, but it can still only capture the same f/stop range. Currently the Nikon D800 has the largest dynamic range of around 14 stops. The human eye is at least 25 stops.

xxdrakexx
14-08-2012, 1:52pm
:umm::umm: not knowing much about this but from my experience with ISO id probably say no

Tai
14-08-2012, 2:01pm
So my dynamic range would stay the same the only difference would be that by increasing the ISO would only move the midpoint of my zone ruler (zone V) to the right (highlight) side therefore giving a greater range to the left (shadows) side which when I think about it makes sense as part of the idea about higher ISO is that it allows you to take pictures in lower light (i.e. shadows) whilst keeping the shutter speed fast(er)

And my photos may be effected by some noise but the dynamic range of my camera would stay the same.

JM Tran
14-08-2012, 2:04pm
Hello Tai, yes you are correct. The 5D2 has never been that great for dynamic range - there is noticeable difference between a D700 and a 5D2 side by side at the same settings - with the D700 showing more details, especially in the highlights and shadows.

The base ISO of the camera is where you would yield the most dynamic range and detail, the higher the ISO, the less detail would be shown - when everything else is equal. With 100 ISO being the base for the 5D2, going down to 50 ISO on it is not its native ISO.

Raising ISO *does* make you loose dynamic range. Thom Hogan in his book discussed this in detail.

Going from ISO 200 to 1600 gives you a loss of 1.5-2 stops of dynamic range on the D700. It is closer to 3.5 stops on a D200. Other cameras will give you the same or greater range losses.

ricktas
14-08-2012, 2:22pm
Hey Tai, now that we have helped you out with two of your assignments, how about giving something back. Post some photos for critique and critique some other members photos. AP is about GIVING as well as receiving from each other.

Sifor
14-08-2012, 3:42pm
I was under the assumption the dynamic range decreases significantly with higher ISOs. I refer to Matt Granger's video who looks at the DXO Mark data:

http://www.youtube.com/watch?v=wFHJfc_N6NM&feature=plcp

swifty
14-08-2012, 6:25pm
In theory you would loose DR as you increase ISO.
Reason being you actually don't increase the sensitivity of your sensor as you increase ISO. What you do is increase amplification.
So effectively for the same scene with equal amounts of light, when you use a higher ISO you're actually underexposing and relying on the camera's ADC to apply the gains to get the same 'brightness' as a shot done at base ISO which has received more 'total exposure' due to either longer shutter speeds or wider aperture or both.
You also loose DR going the other way, ie. going from base ISO to below that. You're essentially overexposing and the ADC reduces (as oppose to amplifies) that data. So you loose DR from the highlights doing this.

Kym
14-08-2012, 6:39pm
This helps...
http://www.ausphotography.net.au/forum/showlibrary.php?title=New_To_Photography:Why_does_higher_ISO_cause_image_noise

As said above the amplification process makes the dark areas noisier, so removing that noise loses dynamic range.
It's all about the physics of photons to sensor to a voltage.

ameerat42
14-08-2012, 7:41pm
(What food for thought! I think I'm ready to order now.
I'll have dynamic range eggs with a serving of photons, pixellated, but hold the ISO to base level.
And waiter, please ask the other table to keep the noise level down.)

etherial
14-08-2012, 7:42pm
I am by no means and expert on this! But I was under the impression higher ISO meant a reduction in dynamic range. An example of this can be seen by this test data from DxO. http://www.dxomark.com/index.php/Cameras/Camera-Sensor-Database/Canon/EOS-5D-Mark-III and click on measurements and then dynamic range.

Mark L
14-08-2012, 10:55pm
G'day Tai, from just down the road!!
I've leant a little because of your thread.
If we're not shooting in extreme conditions, do you think knowing any of this will help us take better photos? (this isn't a loaded question!)

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......
I would go out and redo the test again and I plan to but it is raining very heavily today so I thought I would post on here and see what everyone else thinks of this question while I wait for a better day to go outside.
......

Most have been a freak cloud over Dubbo.

92246

Sorry.
You can still answer my above question, 'cause I am interested in that.

Tai
22-08-2012, 1:34pm
G'day Tai, from just down the road!!
I've leant a little because of your thread.
If we're not shooting in extreme conditions, do you think knowing any of this will help us take better photos? (this isn't a loaded question!)

- - - Updated - - -



Most have been a freak cloud over Dubbo.

92246

Sorry.
You can still answer my above question, 'cause I am interested in that.

--------

Your commont highly confused me until I went back and looked at the location that I was apparently at when I posted that question. My friend set this account up for me and she lives in Dubbo so thats probably why my location says I am there, probably gonna have to fix that. But I can assure you I do not live in dubbo nor was I there when I posted that question in fact I was six hours away visiting relatives so don't know if you were trying to call me a liar or just be funny but seriously dude did you ever think that maybe I wasn't in dubbo at the time? Why would I lie about what the weather.... you sir have way to much time on your hands.

But anyway I will still answer your question as I posted on here to get help and not have petty little arguments over the weather...

Yes I do think knowing this will help me. As I said I am new to photography and just trying to learn as much as I can and dynamic range was something that confused the hell out of me. By knowing a bit more about it I have been able to wrap my head around lighting a little bit more and understand exposure and ISO a whole lot better. I know it was a random question but when I stumbled across the term dynamic range I just couldn't find a site or anything that explained it simple enough for me to understand what I wanted to know about it. Hope that answers your question.


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Thank you everyone for your comments it has helped me understand this a lot better and I think this in the long run will help me achieve better pictures as this has helped me understand exposure a lot better when I put it together with my other notes, Thank you again!! :) xx

Mark L
22-08-2012, 10:09pm
Good on you for answering the question Tai. As i said, I've learned from this thread.


.......dude did you ever think that maybe I wasn't in dubbo at the time? Why would I lie about what the weather.... you sir have way to much time on your hands.

Yes I did, though can only go on the info provided. It took less than 30 seconds.
Anyway, off to contribute to the forums (hint).