Adjusting the ISO - is that permanent?

[Karel Bata]

Just checking whether adjusting the ISO rating is permanent. Like, it's not like the color temperature is it - where the RAW image is unaffected, but the monitor output changes? Changing the ISO does affect what you're recording.

Am I right? It's not too clear in the manual.
.

p.s. What's your experience with noise at the more extreme settings?

[Lauri Kettunen]

No, the ISO setting is just metadata which you can change in post. The ISO setting neither affects the actual signal stored by the camera.

[Graeme Nattress]

It's metadata - it's not permanent and doesn't change the raw data recorded. I think the confusion arises because when you adjust the ISO you change overall image brightness which can effect your exposure decisions.

Graeme

[Stuart English]

ISO affects how the light falling on the sensor is metered by the Histogram. The RAW specific meters are ISO independent.

So ISO adjustments CAN affect what you record, but ONLY if you make a shutter speed or aperture adjustment that alters the amount of light hitting the sensor. So we often use ISO to bias our exposure feedback - image brightness and histogram - for highlight protection.

[Karel Bata]

Ah. That makes sense. It's not regular video.

Is there any way to affect sensitivity without adjusting shutter speed or lens stop? NDs seem to be the only way.

Yes, I know it's a strange question, but it's for an experimental application.

Cheers guys.

[Gunleik Groven]

ND's are indeed your friend for exactly this aplication... -:)
If you are in a controlled light situation, you could also use a dimmer...

Cheers!
G

[Paul Hazlett]

J
p.s. What's your experience with noise at the more extreme settings?

I have shot up to 1280 ISO with tungsten lighting, and got very clean blacks.
others have shot up to 1600 with similar results, some have even reported
shooting up to 2000 iso with noise reduction.

[Karel Bata]

That's good enough for me. Thanks!

[Pablo Villegas S.]

Well, it depends how do you expose with the RED.

If you change the ISO and monitor and expose using REDcolor, then yeah, the image will be affected by the ISO change.

If you change the ISO and expose using RAW, then it will not affect the image recorded, but also, it will make no sense.