Juan Melara

I can't compare it directly to the P4K as I don't regularly shoot with one. But it compares quite well with the P6K and the Alexa. As I said elsewhere the P6K has 1.3 stops more range in the highlights at IOS800 when highlight recovery is enabled. But the Komodo has nicer finer grained noise with no CMOS smear. I'm getting pretty much the same image from both. The P6K requires a Rawlite OLPF filter though. Usability wise the P6K is maybe a bit nicer. So much quicker to shoot with assignable buttons, 2 sec startup time.

Got my hands on Red Komodo to test for a few days. I'm impressed. A few more images can be seen here: https://imgur.com/a/HAWFShe

Hi all, after several requests I've now updated the P4K2Alexa and P6K2Alexa PowerGrades with new ACES versions. This allows you to match the Alexa when working in Resolve's ACES colour science. It's a free upgrade, get in touch if you never received your update email.

That's going to be tough if not impossible to correct completely. If it's a short video I would look at qualifying and using shapes to isolate and correct as much as possible. If it's long, I would probably see how far the first methods I suggested could get you. Followed by making it B&W. And if that isn't acceptable I would look at reshooting.

It could be pretty difficult to correct. I would start by shooting an outside scene with and without those filters. Use shutter speed to compensate for the lack of ND on the unfiltered shot. Take both into Resolve and use temp and tint to get as close as possible to the unfiltered version. Then use the RGB curves to correct any non linear differences. And depending on how bad it is you might need to use hue v hue, or even qualify and correct specific colours.

Beyond charts, I didn't put them side by side. But in real world testing the difference in highlight range is hard to notice in most situations. At ISO800 theres 6.5 stops above middle gray for the P4K, 6.9 on the P6K, 7.8 on the Alexa. On charts the differences are easy to see. In the real world with correct exposure anything above about 6-7 stops is into extreme highlight territory, which doesn't actually occur often in outdoor scenes. In all the P4K/Alexa sample images in this post it's only the lights in the dusk shot that are beyond 7 stops. So for most shots the extra ~0.4 stop is hard to notice. Where it would be noticeable is if you place anything important up in that range and try and bring it back, like those tests you linked to.

Here you go: Visit the Vimeo link to download a full res 3840x1080 Prores 422HQ file.

I would say it's because the Alexa is already doing highlight recovery as part of it's dual gain architecture. ARRIRAW or Prores recording, It's on by default. You can set to tint to whatever makes your image look good. 0 is just the suggested value as that creates the most neutral response across the entire luminance range for most scenarios. Apart from general colour, the two main areas the Alexa excels at is dynamic range and handling mixed temperature or off temp light sources. The PowerGrade can't change dynamic range so it doesn't help there. But the way you expose on set and the ISO you rate the camera, can close the gap. For mixed temp sources, as long as you are prepared to adjust the white balance and tint, you can get pretty close.

The sensors are different enough that I wouldn't even think they are part of the same family. I actually wasn't expecting that. It required a bit of work to even out the non linear quirks. As long as you process the footage at 0 tint, P4K2Alexa will sort out the red channel, well all channels actually.

It's not easy is it! To make it easier, the best workflow is to linearise the GH5, make the corrections, then return it back to log. That means shooting in a gamma that can be converted to linear via a CST, or via something like Lattice. If you don't linearise, you'll be forever chasing your tail. A correction at 0EXP will throw something out at 2EXP, fix it at 2EXP and you've just thrown it back out at 0EXP. When you linearise you remove the variability of the log curve, which can make it so much easier.

I was going to send it to you for free, but then you wouldn't appear on the customer list, so you wouldn't get any free updates. Flick me an email and I'll get you a full refund or figure something out. You definitely want this version as the sensors are quite different. I could make one. Just need to see what the demand is like and then would need to source the cameras. Yeah there's a good stop and a half extra on the Alexa. Highlight recovery brings that down to maybe a stop difference. I'm glad you didn't mention the Alexa's "highlight roll-off." The Alexa doesn't have a highlight roll-off! It's completely linear up there.

P4K2Alexa is out. Accurately match BMPCC 4K footage to the ARRI Alexa via a clean, non destructive 3x3 matrix. With none of the downsides of using a LUT. Fully editable, no clipping, no clamping, no snake oil. https://juanmelara.com.au/products/bmpcc-4k-to-alexa-powergrade-and-luts

After many requests, P4K2Alexa PowerGrade + LUTs coming in the next day or two. Dawn to dusk, one PowerGrade, no adjustments to the transform.

The Cinema 5D guys measured at ISO400. Rating and exposing at ISO800 shifts the mid point, allocating one stop extra to the highlights. It also lifts the shadows, revealing one more stop down the bottom. That last stop will be slightly noisy. And thats what can make measuring DR tricky, as each tester will have a different tolerance to what is an acceptable level noise and whether the bottom stops actually count towards usable dynamic range. And if you're Red, just count everything and say it's 17+ stops. Here is another image to show you the bottom stops of both cameras The previous example didn't have deep enough shadows to crop into. The exposure is matched on the day with false colour, this time I reckon they're identical. No noise reduction. Shot BRAW 5:1 / Prores 444 on the Alexa, which would be compressing out a bit of noise. Remember that the P6K has actually been cropped in to match the FOV of the Alexa, as I shot a 25mm on P6K and a 35mm on the Alexa. The crop is 1.32, so I'm actually only using a 4.6K portion of sensor. It would be less noise if I used the full sensor and scaled down.

Yeah that info was gone on the Alexa. The Alexa was shooting Prores 444, but there is no difference in dynamic range between Prores 444 and ARRIRAW. And there is no highlight recovery on ARRIRAW either, so there would be no chance of bringing it back.