You may have seen that Sony are releasing a free firmware update in the next week or so for the PMW-F3 that incorporates a new version of S-Log. You will still need to have purchased the S-Log upgrade in order to use S-Log, but now there are two variations of S-Log, normal S-Log and EI S-Log.
EI S-log differs from the original S-Log in that the base ISO is 800 as opposed to the 1600 of the original. You can select either S-Log or EI S-Log mode in the menu. When EI S-Log is selected you have the ability to then add EI gain to the MLUT’s (Monitor Look Up Tables or LUT’s). When you switch the EI ISO to 1200 for example, the additional gain is added to the LUT to give the equivalent S-Log + 3db gain output on the monitor out and to the SxS card recordings as using S-Log with gain. But the actual S-Log output on the A-B dual link outputs remains fixed at 800 ISO. The benefit of this is that what you see on the monitor out represents what you will end up with after post production with added gain or lift, it’s a way of pre-visualising what you will finish up with, without compromising your recordings.
Theoretically, if the cameras native 0db gain point is represented by 800 ISO. Which is what you have when using 50/60i standard gamma at 0db. Reducing the cameras S-Log gain like this by 6db compared to the previous or standard S-log base ISO of 1600. Should yield a 6db (1 stop) dynamic range improvement. Given that S-Log already improves the dynamic range by about 1.5 stops, then on paper at least, EI S-Log should yield a 2.5 stop improvement over the 11 stops the standard and cinegammas give. That would make the F3 a camera capable of 13.5 stops which is quite remarkable. I hope to be able to measure the actual DR very soon and see if this is really the case. Anyway, whatever the outcome of the DR measurements, the EI option is a nice one to have as it will allow you to underexpose a little (to gain extra headroom) when you shoot and then use the added EI LUT gain to check that even after gain gets added in post the images will still be noise free enough for use in your production.
A further feature of the update is the ability to change the R and B gain when shooting in S-Log. This will allow you to tweak your white balance. Currently when shooting s-Log you can only use a preset white balance dialled in in 100k steps, there is no option to white balance the camera using a grey/white card.
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