5.7k Anamorphic with Dual ISO on 5D3

[Tyronetheterrible]

I am shooting a horror short film on my 5D3, and want to take advantage of the beautiful image captured in 5.7k anamorphic mode, as well Dual ISO, as it will be a very high-contrast scene.

Has anyone been able to successfully implement both features at the same time? I seem to get a blue-ish glow around every detail of the image when I am viewing the clips in MLVApp, after enabling Dual ISO on in MLVApp. I've tried experimenting with different pairings of ISOs to no avail, and I've been able to get both Anamorphic and Dual ISO to work just fine on their own respectively.

Any suggestions or tips would be great! Thanks in advance, community!

[Walter Schulz]

Maybe start to tell the build version you are using and your Dual-ISO settings.

If able share a short unprocessed footage file.

[Tyronetheterrible]

Hey Walter,

Thanks for the timely response! I'm using asintes' crop_rec_4k_mlv_snd_isogain_1x3_presets_ultrafast_fsq_2024Mar27 build:







Here is a link to an unprocessed file:
https://www.dropbox.com/scl/fo/anhvujulas7apmnpceln6/ADd29czxVSzF1hrA7luXhE0?rlkey=thbzmeyecsu6rnjzr5etl1nzp&st=5w8yxqyv&dl=0

[Walter Schulz]

Thanks!
Cream on top if you are able to share two pics with Tv/Av/ISO used for video (ISO=base and expanded as used in Dual-ISO). Don't change focus, please!
I have a suspect and with those pics it would be easy to tell if I'm wrong or not.

[masc]

Try to switch off vertical stripes fix. Fixes your problem 100% here.

[Walter Schulz]

Thanks! Didn't catch that! ;-)

[Tyronetheterrible]

ISO 100, -0,3EV:



DUAL-ISO 100/1600:



Turning Vertical Stripes OFF as per masc, appears to have remedied it, although, should this much moire in the window be expected? relative to the ISO 100 shot?

ISO 100, -0,3EV:

DUAL-ISO 100/1600:

[masc]

Open aperture as much as possible against moiree.

[Walter Schulz]

Moiré is unpredictable and we have no way to reproduce your environment.

In cams like 5D3 with "banana-shaped" DR curves I use ISO 200. According to Photons To Photos you lose just 0.2 PDR but gain 1 EV.
With this setting I would rather use 200/1600.

Also: Are you sure about ISO 80? Haven't experimented that much with tweaking this setting, though.

[Tyronetheterrible]

Open aperture as much as possible against moiree.

Thank you so much masc, and Walter, for helping me with this issue. I am extremely appreciative!

If I could garner your expertise once more, what would the best way to expose using Dual ISO if I were shooting a scene with a high contrast ratio such as this:



I would be locked in at f8, and 1/48 shutter.

Wanting to avoid as much noise as possible, how would I use ETTR in this scenario?

My newbie brain would think to try and first expose at ISO 100 to just before highlights clip, before enabling Dual ISO, but I suppose I'm wondering how far high for the second ISO could I use given the 5D3s capabilities?

According to Photons To Photos you lose just 0.2 PDR but gain 1 EV.
With this setting I would rather use 200/1600.

Thank you for linking this fantastic resource! Does this data directly apply to movie mode as well?

Also: Are you sure about ISO 80? Haven't experimented that much with tweaking this setting, though.

I am not sure at all to be honest. I was just experimenting after reading on another post about setting ML digital ISO to -0.3EV. Have not gotten around to any meaningful comparisons.

[Walter Schulz]

Keep in mind about viewing conditions "in the wild".
Viewing high contrast content requires optimal lighting. The kind of non-lighting you find in a movie theatre. No disturbing light or your dark areas will get lost.
My dated non-HDR, non-OLED monitor is only able to show its full potential if i pull down the blinds during daytime.
If you are sure all your efforts will not be lost I would think about 2 options:
- Damn the highlight showing in lamp and reflection and fix it in post.
- ETTR the hell out of it as you described.

Balancing base ISO and extension remains a balancing act. The further you stretch between both the higher the risk of getting visible artifacts. I have to admit not to be a big fan of Dual-ISO. I avoid it most of the time. That's easy because my kind of work doesn't force me to use it.
Maybe I'm the wrong person to be asked about Dual-ISO for movie making. ;-)

[iaburn]

I'm not an expert, but this scene looks like it won't need more than 6 stops of dynamic range. Just ETTR, and in post adjust exposure and clip the blacks with a steep curve when they became noisy

[Danne]

Here comes the party pooper. My advice. Skip dual iso in movie files. For stills, very nice, for video, bad. Code will sooner or later cause subtle errors in image and soon you'll spend countless hours trying to fix or understand what's going on.

For instance. Vertical stripes correction will work with one version but not with others.

Instead, master the ettr and learn to live with some blown highlights when that happens.

[HiphopMoment]

1、为什么不用大光圈镜头来弱化摩尔纹，只要焦点在主体上就够了。
2、双iso选项那里可以选择自动+3档，这样可以很好的节省时间。

5.7k我用着很好，比尼康z63的nraw码率省多了。

[Tyronetheterrible]

Thank you everyone for the feedback. It's given me a lot to consider!

I think given the technical and creative freedom I'm being given on this project, I am going to try to shoot it in both ISO 100, as well as Dual-ISO.

The film will essentially be a 4 minute single shot, fixed on a tripod, zooming in from wide, all the way to a close-up, for a slow, steady 4-minute duration. No tilting, panning or other camera movements involved. So trying it in both modes would be no more than shooting "one more take for safety".

Although the high contrast example I posted above is similar to what I'll be shooting, there will be moments where a high powered light will be directed towards the camera's direction in an otherwise "dark" environment, save for some room tone I'll be subtly bouncing in the room.

I'll keep you guys posted and share the video once I've finished it! I'd love to hear everyone's thoughts on it.