# can I change ISO settings in Lightroom3?



## cameragirl (Oct 6, 2010)

I watched a demo for noise reduction in Lightroom3 and noticed it was possible to change ISO settings. But it did not show how to do this. My question actually is that I took some photos last week and forgot to change the ISO from 1'' tot 8''. Is it possible to fix this in Lightroom?


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## ukbrown (Oct 6, 2010)

I don't think you can change the ISO. You can if shooting in RAW try to get more detail out of the dark areas.

In a digital camera the ISO says how sensitive you make the sensor, more sensitive more noise. Then the camera works out the correct exposure for this sensitivity.


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## tzalman (Oct 6, 2010)

In a digital camera the ISO says how much the signal coming from the sensor is amplified, the sensor itself remains the same. Increasing 'Exposure' in LR can simulate digitally the effect of increasing ISO. +3 Exposure will be a simulation of a change from ISO 1'' to ISO 8''. In fact, your camera does this also; when you change the dial from ISO 1'' to ISO 125 or when you switch it to one of the "Extended" high ISO settings, the change is done digitally (by software). It is only the changes by hundreds - 1'', 2'', etc. - that are done electronically (by hardware). So yes, it can be done in LR, but.... (and it's a big but) hardware always beats software. You will always be better off raising the ISO in camera and getting adequate exposure than trying to correct mistakes with LR, but if you are willing to accept the loss of quality involved because the shot is important and unrepeatable, LR can do wonders.


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## clee01l (Oct 6, 2010)

As you probably know, there is a 'correct' combination of ISO(Sensitivity), Aperture and Shutter Speed that can be combined for a properly exposed photo. While all three are fixed in the camera at the time the photo was taken, the EV can be adjusted on the RAW data after the photo was taken. This is usually expressed in +/- f/stops in LR. In reality what you are doing is changing the amplification factor of the pixels at the sensor. This amplification is really what would happen in the camera if you were to change the ISO.


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## sizzlingbadger (Oct 6, 2010)

You cannot change the ISO after you have taken the shot. This is the same for shutter speed and aperture also. You can reduce the noise that is produced at higher ISO's using the details panel. You may also be able to get some of the dynamic range back (this is also reduced as your ISO is increased) by using the recovery tool but that will depend on the image and exposure that was taken.

Attached is a test I did with my Nikon D3'' (Native ISO 2''), you can see that the dynamic range is reduced by almost a whole stop at ISO 8''. This is also apparent at ISO 1''.


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