Sony EX-1R ISO Rating.

[Sara Jourhmane]

Andy did an excellent Sony F3 Iso Rating Test here.

AbelCine Tests the Sony F3 ISO Rating | CineTechnica


I was wondering how EX-1R / EX-3 rates?

[Les Wilson]

Sara, this shows up at various times in various threads. Do a search on "EX1 ISO" and you'll see what I mean. Here's one:
http://www.dvinfo.net/forum/sony-avc...ml#post1675636

I'm not sure but I think Alister Chapman may have done a test of it. However, an IT accident early this year caused a loss of some his work. You can find the remnants and all the more recent work here:
XDCAM-USER.COM | Alisters XDCAM blog and cinematography resource.

[David Heath]

Beware how many conclusions you draw from ISO ratings - in particular, they are NOT (in themselves) a measure of intrinsic sensitivity.

What they DO tell you is what aperture the lens should be set to at a given gain setting, and at a given light level to get correct exposure.

IF the signal-noise ratio of all cameras was the same at nominal 0dB, they would accurately reflect intrinsic sensitivity - but that isn't the case.

Hence it's quite possible for two cameras to have the same 0dB ISO rating. But if camera A had a better s/n ratio, you could then use far more gain than camera B for comparable results - it would perform far better in low lighting levels.

[Doug Jensen]

it's very important to keep in mind that the ISO rating is completely dependent on the camera's paint menus settings and other variables. In my opinion, Abel does not stress this enough in their report, even though, to their credit, they do give plenty of details on the specific camera settings that were used during their testing. I'm sure Andy's results are right on -- but only with those settings.

They rate the camera at ISO 800, but I would never shoot with the settings they use, so that ISO number is meaningless to me. If I exposed for ISO 800 on my camera, everything would be underexposed by almost two stops. I have rated my F3 at IS0 250 with the normal Picture Profile I use most often, and at ISO 1000 when shooting S-LOG. Obviously, my numbers would be probably be wrong for someone else using different settings.

I've never bothered to rate my EX1 because there's not much reason to do so. I suppose I could if someone really wanted to know, but again, the results would be meaningless for anyone not using the exact same settings. And as David points out, ISO on camera A compared to camera B doesn't mean much if you don't take noise into consideration.

[Alister Chapman]

Wow, I'm very surprised by your ISO numbers for the F3 Doug especially S-Log where you can't change any of the camera settings other than gain. Sony's figures of 1600 ISO for interlace and 800 for P appear pretty accurate to me, like wise with the standard setup using Gamma 5, as per Abel I also I get 400 ASA.

For the EX1/EX 3 I rated them at about 320-350 ISO in Progressive.

[Doug Jensen]

Yup, I stand by those numbers for progressive and have checked it on more than one occassion. I am 100% certain my numbers are correct for my camera.