PDA

View Full Version : Getting the most out of the new OLPF



Luke Neumann
08-03-2014, 03:45 PM
I get my Dragon tomorrow and instantly jump into a shoot with very little time to do testing so I was just wondering if someone could share their preferred workflow at this point in time. Last I heard people were getting great results at ISO250, now I'm hearing 800 again. I don't mind a bit of noise, even MX noise, I just want the best roll off/DR and I'm assuming that's at 800.

Any advice would be greatly appreciated!

Jeff Kilgroe
08-03-2014, 03:58 PM
Rating at 800 is fine for daylight sources. It handles tungsten better than MX, but I tend to rate ISO lower in such a setting still. Keep a close eye on the traffic lights and goal posts for exposure. The goal posts, in particular -- the left side low goal post is essentially your "noise meter." IMO, the histogram, etc.. You'll actually want to be on the latest beta build of the firmware as it will give you the best match for the histogram and other meters to your exposure with the new OLPF profile. If you feel you need to roll with release version firmware, and that is understandable, the 5.1.55 build does not seem to align the exposure and meters as well, but the lights and goal posts still seem to function mostly right. If you do encounter noise, the release build doesn't have the fixes in it for the red colored chroma noise. Redcine-X that addresses the new Dragon noise handling is in a limited release beta at the moment.

Try to do whatever testing and familiarization you can ahead of your shoot. steal some test shots while setting up at the shoot if you can. Don't be afraid to rate ISO a bit low to compensate for the chance of under-exposure and noise. There is quite a bit of range to work with here, Dragon really does have 16 stops to work with if you light and expose well. And the highlight handling and roll-off is beautiful if you over-expose.

All that said, I tend to consider ISO to be about 400~500. 320 in tungsten lighting. I did this on MX, too. But I think it looks even better with Dragon as it does block a little more light with the new OLPF and the highlights are just better looking overall. I'm not afraid to blow some highlights now and then, but I like that look. Just as long as I don't blow the sky out of a shot or know that I can replace it in post. Dragon has good DR to hold well in a lot of those situations.

Luke Neumann
08-03-2014, 04:35 PM
Thanks a million Jeff! I will be referring back to your post often in the coming days. Will try to get as much time before the shoot at possible.

Martin Stevens
08-03-2014, 07:28 PM
800 ISO is fine... lots of major features are using that ISO.

Jeff Kilgroe
08-06-2014, 11:52 AM
It's a shame that this thread is getting no love, while the new OLPF / Dragon noise hate mongering continues in other threads. Here is what I had to say about ISO in one of those other threads, but I feel it's worth repeating. ISO as it pertains to RED is still grossly misunderstood.


Looking back in this thread over the past few weeks, it's no wonder why so many people have problems. I see Paul has been put on temporary lock-down, but he makes a valid point when asking if people actually use their cameras!

First things first, ISO control on RED cameras *IS NOT* the same as ISO ratings on film, or many other digital systems that impose various forms of gain. We keep trying to drive home the point that ISO is only a value contained in metadata and the recorded image does not change due to ISO setting. But the one thing many seem to miss is that ISO is not a measure of brightness. ISO isn't even ISO in the RED ecosystem, it should be the Exposure Index or EI rating, which many of us asked for it to be called way back in the early R1 days. Unfortunately, people want "ISO" because they think they know what it is.

On a RED camera, doesn't matter if it's original RED One with Mysterium sensor or if it's the latest Dragon with the 'new' OLPF, ISO is the index point to which we reference middle grey on our exposure curve. That is it.

Trying to 'rate' the camera or sensor is something different than this meta ISO value. It is not a hard value. Is the Dragon an ISO 320 camera? YES. Is the Dragon an ISO 800 camera? YES. I can rate and shoot for ISO 2000 and still walk away with a clean image if my lowest exposure points of the image are above the useable noise floor. EDIT> This noise floor DOES NOT CHANGE with ISO setting.

The camera, at the sensor stack/OLPF level, has a valid signal to noise range. At the low end of that range, if too little light comes in contact with photo receptors on the sensor, there is too little signal to overcome the chatter of erroneous noise. This chatter or cross-talk or low db on the signal scale, which translates to garbage that exists below the 'noise floor' shows up as unwanted noise in our images. It can be seen with the left goal post meter on the left-hand side of the histogram in our cameras. At the other end of the useable signal range, too much light will overload the receptors and put them into overflow, values are clipped at maximum. We see that as the right-hand goal post meter. These values can also be referenced in the 'traffic lights' but the goal posts seem to be more useable, the traffic lights are more of a warning to say "hey, take a minute and look at your meters!"

The histogram is useful, but it exists within translated exposure and color space with an assumption of an 800 ISO curve. It does not tell the full story. We can try to avoid some noise or undesirable image properties by "exposing to the right." However, that is just a means of avoidance and doesn't address a shortcoming in our lighting or exposure practices.

One must always consider the low and high limits of the sensor and keep in mind that the ISO value is just a reference point for our curve somewhere in the middle. If we are seeing excessive noise in the shadows at ISO 800, that noise is still going to be there if we re-rate at ISO 320. We may cover it up by lowering the ISO index value and effectively crushing in on the exposure curve below middle grey.

And there's this little nugget to consider and I wholeheartedly agree:


Having shot a TON with the "old" OLPF - and the "new" OLPF - I'd take the "new" OLPF pretty much 95% of the time. And honestly ... for the 5% of time I'd choose the "old" OLPF - I'd most likely be better served with a slower shutter speed - but slower shutter speeds scare people more than they should and that's a topic for another thread.

Roger Viloria
08-06-2014, 11:55 AM
ISO 400 for dark/indoors
ISO 800 for bright/outdoors

David Battistella
08-06-2014, 12:07 PM
I get my Dragon tomorrow and instantly jump into a shoot with very little time to do testing so I was just wondering if someone could share their preferred workflow at this point in time. Last I heard people were getting great results at ISO250, now I'm hearing 800 again. I don't mind a bit of noise, even MX noise, I just want the best roll off/DR and I'm assuming that's at 800.

Any advice would be greatly appreciated!

Hey luke,

you can rate at 800 just fine, you'll notice you can open up much more without clipping so you can afford to push it more than you would MX. I had to go though a few weeks of mental "protect the highlights" deprograming (in my own mind) because dragon gives you more room up top.

The raw view is now 5600k 800iso redlogfilm,

keep an eye on both goalposts, while dragon seems like it's noise goalpost is filling up faster, if you use the exposure tool you will see your blacks are not in the purple zone.

the monitor touchscreen image tends to be a fair bit brighter than what you will open up in RCX but not a huge cause for concern, just a heads up.

Battery power is about the same.

11:1 on dragon looks like 8:1 on epic. 8:1 is a good all purpose compression ratio.

I recommend using secure format on all your media before starting the shoot. I have had some media fragmentation errors when filling up a card to more than 90%. No problem with the media, just an error message that comes up the next time the media is cycled.

Black shade your dragon at operating temperature when you get it.

the camera now boots in about 32 seconds, it's takes some getting used to over MX.

if I think of anything else I will edit this post.

happy shooting!

Battistella

Luke Neumann
08-06-2014, 12:58 PM
Thanks so much for all of this info! Got the Dragon two days ago and had a day just to mess around. Instantly notice the highlight protection and the colors are near perfect. Everything I loved about MX but that much better. Love shooting on it so far!

Juan D Salazar
08-07-2014, 05:56 AM
Great thnx for sharing all that info guys ;) Trying to get the most of my Dragon here as well!