Magic Lantern Forum

The opening scene of this video is by far the darkest scene I have yet pulled off, far darker than the candlelit scene (which had nothing but 6 candles).
ISO 1250, shot at 3616*1536, 14 bit lossless with card spanning and overclock.  NO noise reduction, exposed for the fiber optic light curio.

The rest of the video is dual ISO with much more light.

Watch in 4k in a very dark room!

Read the video description for more info.

https://www.youtube.com/watch?v=-aE-HSdVtYk

nice and clean, how to implement in 700d? I got very noise video when try to shoot in room light condition. with dual iso I got very dark barely can't see anything in the video and if exposure increased the noise is very bad

Very nice, 70MM13 - one of your best low-light videos in my opinion.  And beautiful music too!  Please don't worry about your 5D3.  It will last longer than you think!

ML700D,

No matter what camera you use, you still have to expose to the right (ETTR) when filming at Dual ISO.  Needless to say that you should use Dual ISO only in the high-resolution modes with enough vertical resolution, (the 1x1 or 1x3 crop modes).  Activate your Zebras and Histogram, find your brightest spot in your scene, magnify it and start increasing the exposure until zebra stripes start showing up on that spot. Then dial the exposure down by 0 to 1/3 of a stop and watch the histogram.  If it shows an exposure reading between 0,1 and 0,3 you should be fine since you will be close to the highest signal-to-noise ratio (SNR) in the darks without blowing up the highlights.  Also play around with the Dual ISO numbers.  The 100/800 setting provides excellent results when there is enough light.  When it is too dark though, then 200/1600 or even 400/3200 may provide better results.  In scenes with very high contrast, you may want to increase the second number by one more stop, e.g. 100/1600, 200/3200. 

And last but not least - do not try to push the Shadows too much in post!  If you do, at a certain point, you will get ugly noise artefacts in the darkest areas.  An image with minimum detail in the darks looks much better than one with noisy shadows!

And finally, practice, practice, practice!  If you do, you will very soon find out what ML is really up to.

thanks for your advice IDA_ML

does this also apply in low light conditions?
I ever used dual iso in room light (18w led bulb) at night but the result was almost black.

Quote from: ML700D on January 22, 2022, 05:18:03 PM
does this also apply in low light conditions?

Of course it applies to low light too!  But you seem to prefer asking questions instead of testing by yourself.  Just follow the procedure that I described in my previous post and check by yourself.  It will take you just a few seconds.  18 Watts is a lot!  You should get an excellent image with that much light.

Here is a short room sample at 100/800 that I have just shot for you:

https://we.tl/t-QmeuJot9E1

The light bulb is just 11W.  Post processing and downsizing to FHD was done in MLVApp.  A short sample of the original MLV is also included for you to see all settings.

Quote from: IDA_ML on January 22, 2022, 08:18:23 PM
Of course it applies to low light too!  But you seem to prefer asking questions instead of testing by yourself.  Just follow the procedure that I described in my previous post and check by yourself.  It will take you just a few seconds.  18 Watts is a lot!  You should get an excellent image with that much light.

sorry for that, it's because of my past experience ..  😁

Quote from: IDA_ML on January 22, 2022, 08:18:23 PM

Here is a short room sample at 100/800 that I have just shot for you:

https://we.tl/t-QmeuJot9E1

The light bulb is just 11W.  Post processing and downsizing to FHD was done in MLVApp.  A short sample of the original MLV is also included for you to see all settings.

thanks IDA_ML.. I can't believe my eyes, I have to try soon haha..😂
unfortunately the setting you told is not included.. but it's ok.

Quote from: ML700D on January 23, 2022, 05:08:31 AM
unfortunately the setting you told is not included.. but it's ok.

Open the MLV sample in MLVApp and press the Info button.  You will see all the camera settings the file was shot at!  Then you can use these same settings to film your own tests at 18W LED lighting.  Compare your results with and without Dual ISO and  post them here.

oh I see.. yes, sir. :D

Quote from: IDA_ML on January 23, 2022, 07:41:03 AM
Open the MLV sample in MLVApp and press the Info button.  You will see all the camera settings the file was shot at!  Then you can use these same settings to film your own tests at 18W LED lighting.  Compare your results with and without Dual ISO and  post them here.

with dual iso 100/800 f2.0 crop rec 1x3 4.5K




without dual iso 800 f2.0 crop rec 1x3 4.5K




those are better than mine before  :D
I don't understand why.. lol

Try increasing the exposure of your Dual ISO shot in MLVApp in such manner that it matches the non Dual ISO one.  Then compare the noise levels in the darkest areas of both shots.

ok. thanks.  :D

Quote from: IDA_ML on January 23, 2022, 07:45:20 PM
Try increasing the exposure of your Dual ISO shot in MLVApp in such manner that it matches the non Dual ISO one.  Then compare the noise levels in the darkest areas of both shots.

I use 640/1600 and 640/3200 dualiso and compared to iso 800 is almost the same i think.

(https://i.ibb.co/pRPW8gk/dualiso640-1600-f2-0-UHD1x3.png)

(https://i.ibb.co/YjS7GKW/dualiso640-3200-f2-0-UHD1x3.png)

Quote from: ML700D on January 24, 2022, 04:00:37 AM
I use 640/1600 and 640/3200 dualiso and compared to iso 800 is almost the same i think.

The reason you barely see a difference is because your scene is evenly lit and its contrast is quite low.  It is well within the dynamic range of your camera and you do not need Dual ISO for it.  Try including also the light bulb in your scene, expose for it and reshoot the scene with and without Dual ISO.  Then you will see the difference.  Dual ISO makes sense only if the contrast of your scene goes beyond the dynamic range of your camera.  In a situation like this, adding 2 to 3 stops of dynamic range with Dual ISO makes a huge difference in the noise of the dark areas.

Just keep experimenting until you understand Dual ISO !!!

I see..
thanks a lot IDA_ML

I did a few test shots in low light and dual ISO did not gave me better noise performance. It also introduced a lot of flickering when the shadows pushes too hard.

As it mentioned by IDA, if there is a light source in the image and the scene is well lit for ISO100/400 or 100/800 ETTR, the results are much better with dual ISO.

For light condition of ISO800 and above you should stick with 5K Ana + single ISO. MLVAPP CinemaDNG export, then Davinci Resolve can do wonders with noise reduction on a 1080p timeline from the 2.7K (1280x2160) source.

in these images I use UHD 1x3 and standard 3x3 and only use mlvapp srgb preset
this time I try to add desk lamp to make it contrast as described.
(https://i.ibb.co/D7nkdKd/dualiso100-800-f2-0-UHD1x3.png)
(https://i.ibb.co/GVVq3qB/dualiso100-1600-f2-0-3x3.png)

then I have no idea what to say.. lol

😁

Quote from: ML700D on January 24, 2022, 11:52:58 AM
then I have no idea what to say.. lol

Well, your 100/800 shot looks pretty good and clean to me.  Look under the table and see if the noise suits you.  If not, buy a RED or Arri Alexa :-)))!

LOL

I just understand a bit and need more practice, I don't expect too much.
being better is more than enough 😄

thanks for your guidance..

I turn off the room light and only use 5w desk led light..
Impressive! I can't believe my eyes 

(https://i.ibb.co/mFwQqzG/dualiso400-3200-f2-0-4-5-K1x3.png)

unfortunately the quality after uploaded to youtube isn't that good when enlarged the view.




I call it hidden noise in the shadow 😄

hey everyone, it's nice to see active discussion again...

i've found that youtube quality goes up if you upload at least 2560 horizontal resolution with a suitably high bitrate such as 20mbps.

i'm preparing for my next music video and it seems like the test shot i made last night with no key light is worth sharing here with you all...  i'll upload it and share a link here.

here is the test clip.
this was shot at iso 800 without dual iso.  the exposure was set for the very bright led bulbs beside the big monitor, with no clipping.  the room is quite dark, with a 15W led bulb behind the large monitor for indirect light.
no noise reduction, but i (always) desaturate the blacks.  any colour there is just chroma noise!
there's no key light in this test. i lifted the shadows by 1.5 stops.
this is a test of the "halation" plugin in resolve.  that's what is making the bright objects glow...

https://www.youtube.com/watch?v=RiMKqWr2OJQ

Quote from: 70MM13 on January 24, 2022, 06:45:59 PM

i've found that youtube quality goes up if you upload at least 2560 horizontal resolution with a suitably high bitrate such as 20mbps.

in this case I uploaded prores 422 4080 x 1976 resolution directly to youtube.
or perhaps because handheld recording? or wrong in setting exposure? I have no idea

using noise reduction in mlvapp can push exposure a bit more. feels like using ARRI cam 🤣

(https://i.ibb.co/8mtHsPS/Screenshot-2022-01-25-084606.png)

(https://i.ibb.co/s2PPsD4/Screenshot-2022-01-25-092224.png)

ISO100 ETTR, pushed about +3EV

(https://i.ibb.co/brmKvRm/Ke-pernyo-foto-2022-01-24-17-52-52.jpg) (https://ibb.co/D7WRMgW)

ISO100/400 Dual ISO, same exposure, pushed about +3EV
(https://i.ibb.co/1JFht7n/Ke-pernyo-foto-2022-01-24-17-52-59.jpg) (https://ibb.co/M5FWxZh)

Nice and indicative example, Deadcode.  The quality improvement with Dual ISO is clearly visible, especially in the darks.

I have been using Dual ISO in high-contrast scenes on a regular basis for quite some time, mainly for street videography at night using the available street light.  I do get flickering ocasionally but it is not all that bad.  In most cases I can cut these flicker portions out.  Overall I have been very pleased with the result - much better compared to single ISO.  Personally, I think that ISO research and Dual ISO are the most significant scientific achievements of our ML devrlopers.

f/2.0 iso 3200 crop_rec 4K 1x3 (1360 x 1976) no room light (with creative adjustment)
(https://i.ibb.co/tC5qBRk/Screenshot-2022-01-30-112754.png)

f/2.0 iso 3200 crop_rec 4K 1x3 (1360 x 1976) no room light (no creative adjustment)
(https://i.ibb.co/SB2Rd0D/Screenshot-2022-01-30-133325.png)

f/2.8 iso 800 crop_rec 4K 1x3 (1360 x 1976) no room light (with creative adjustment)
(https://i.ibb.co/8xrTTQW/Screenshot-2022-01-30-113812.png)

f/2.8 iso 800 crop_rec 4K 1x3 (1360 x 1976) no room light (no creative adjustment)
(https://i.ibb.co/hFvff0w/Screenshot-2022-01-30-132549.png)

70MM13 sorry to post here, just continuing what I've learned from IDA_ML.

Thanks. 🍻