S-Log is one of the most powerful tools in Sony cameras today. It maintains a wide dynamic range and can be pushed very far in post. The biggest problem is properly exposing it. While I’ve had S-Log on my cameras for several years, I’ve always hesitated using it cause it’s hard to light and expose it without LUTs. LUTs are look-up tables that tell the camera, monitor or color grading software how to display the color and luminance values of the image. Just recently Convergent Design added custom LUTs to their Odyssey 7Q recorder which finally made it possible to properly shoot in S-Log out of the FS700. The reason it’s so difficult to shoot in S-Log is that Sony pushes the shadows really high to retain the maximum latitude in dark portions of your image. The problem is, when you try to expose for contrast, you end up under exposing your shot without evening knowing it…that is until you try to grade it and end up with super noisy footage.
The first time I shot S-Log on a commercial project, I exposed the image to retain the sky and to my eye, the talent was still exposed okay. Maybe a little dark, but nothing I haven’t been able to grade back in before. But when I tried grading S-Log, anything even slightly under exposed became very noisy when I brought the levels up. Later on, I discovered that the proper way to shoot S-Log is the expose to the right or over expose the image and bring it back down in post. That’s great, but how do you light for that when it looks all washed out? For example…
Here’s a music video we just shot a week ago. This was the first project I’ve done with the custom LUTs feature of the Odyssey 7Q. This is what it looked like on the 7Q with the LUT turned on:
But this is what the camera was actually recording:
You see what I mean? If I was trying to light to that image, I would have way under exposed it to maintain the contrast and deep tones I wanted for the piece. But with the LUTs enabled, I can properly expose S-Log and bring it into Resolve to make the image match what I saw in the 7Q.
Big difference. It’s great to have the flexibility of S-Log cause I can really push and pull that image around. The key is making sure to always be bringing your shadows back down and never try to bring them up. If you look at the shadow side of her face, you can even see some noise in it. But when I bring the contrast back in, the noise goes away.
So what does this have to do with the A7S? Well, when shooting with the 7Q, I used Convergent Designs’ built in LUT: SONY_EE_SL3C_L709A-2. This gave me the results you saw above. I liked it so much that I loaded it on my Atomos Shogun to use with my A7S. The Shogun is a great monitor and great recorder, but it does guzzle batteries and I find myself sometimes preferring to shoot to the XAVC internally on the A7S. But, if I’m going to shoot S-Log, I’ll need a monitor that can support LUTs…which can be expensive.
Well I recently got in the ikan VH7i which is an inexpensive IPS monitor that has amazing battery life. It’s perfect for the A7S shooter who wants to be lightweight but still have a nice 7″ display. The VH7i doesn’t have the ability to load custom LUTs, but it had something that was almost as good. In the menus, you can go in and change the video display settings to the point where, side by side with my Shogun with the LUT enabled, they were very close. Here are the settings I used:
Now that’s great until you want to use it on another camera without that contrasty of an image. No problem, The monitor allows for multiple User presets so I have my standard settings on User 1 and my S-Log “LUT” on User 2.
This is also great for when we have a wireless client monitor setup with our Paralinx Arrow. I can use the VH7i to show the client/director what the image will look like even out of the FS700.
Of course there are other monitors that will let you do this, the key is making sure you have a “LUT” to see when shooting S-Log so you can light and expose the image for what the grade will be and not what you are recording on the camera. Get this right, and you’ll see a marked improvement in the footage you’re getting.
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