Do i need to worry about ISO?

[enny]

Hi guy with BMPCC that shoots raw do we need to worry about ISO at all some people are saying that you dont need to worry about iso if shooting raw what do you guys think

[Mattias Burling]

Keep it at 800 and your golden.

[enny]

what about if ti is bright outside and you need yo take down the iso or you don't touch iso in that situation

[Nikkor]

Nd filters man, get a good one.

[Guest Ebrahim Saadawi]

what about if ti is bright outside and you need yo take down the iso or you don't touch iso in that situation

You can lower the ISO in these situations but you'll lose dynamic range vs 800 ISO + ND.

The sensor performs best at 800 so expose with other variables rather than ISO (Shutter angle, aperture, ND filtration)

[dhessel]

on the BM cameras ISO has no effect on the raw data. ISO is only stored as metadata but underlying data is the same. It only matters in prores.

[enny]

Is it same situation when it comes to night shoots just leave it on 800 and use Shutter angle, aperture, ect

 

Thanks guys

[Mattias Burling]

I would still use 800 and push in post.

[Guest Ebrahim Saadawi]

@Enny it's an easy test. I always test for anything I am not sure about. Just hold the camera now, shoot at 200, 800, 1600 ISO (with the same exposure using aperture or shutter angle), import in Resolve and see if they're the same. If 200 pushed in resolve to 1600 looks identical to 1600 in-camera, then ISO is irrelevant and you can choose any of them depending on how you like to see on the camera screen. 

Not all raw is ISO-less. Many raw cameras apply the gain on an analog level of the sensor before processing so that it's not a metadata/post property at all but each ISO has different noise levels and dynamic range. 

Test, it's a small test will take 10 minutes maximum. The only way you'll feel comfortable. 

[Axel]

It has been tested very often. In raw, you can use ISO 200 or 400 to see something in the display when using ETTR. The ISO setting has no permanent effect then. In ProRes, as said above, every other ISO than 800 will decrease dynamic range.

[Guest Ebrahim Saadawi]

Then it's that I trust you. I was being skeptic because my experience with Red (MX), where it's a known fact ISO is just metadata, when I shot 320 ISO it was a very different image than 1600 ISO in R3D raw, 320 has less dynamic range and less noise while 1600 has even less dr and more noise, horrible when put down to 320 level in post, It's not a huge difference but it's there, and RedCineX software just named the exposure compensation slider in the NLE (ISO) to give you that comforting feeling knowing the difference is not going to be a noticeable difference. I then learnt to test everything at home before going out. 

ArriRaw is also affected by sensor gain and Canon raw is especially very affected by gain (which they're proud of saying going lower than 850 decreases signal-noise ratio significantly and higher also decreases signal-noise ratio as it's analog electric gain applied on the sensor level rather than in post). Canon CR2 stills and Nikon NEF raws, Pentax DNG raws are also affected by ISO level (Nikon to a much lower degree but stills affected), 

So since Blackmagics are truly not affected by ISO, do the 200 ISO footage import in NLEs already at that exposure or still import as 800 ISO exposure? If it does import at the shooting ISO then it'd be just better to set ISO on shots rather than handing underexposed/overexposed footage for your editor in post and how they might devestatingely leave it at that believing it was your creative choice, and also to avoid the risk on IQ if one decided to transcode rather than edit the DNGs. But if one is working alone and doesn't care about seeing desirable exposure on-set then leaving at 800 can be a viable option to just forget about it entirely. 

I've only shot ProRes HQ on the pocket as back then Vegas didn't import raw files as it does now. So I have no idea about BMPC raw, I wonder how it will import 200 ISO footage vs 800 ISO footage identically or differently (also in premiere/fcpx/lightroom)