Dual ISO - massive dynamic range improvement (dual_iso.mo)

Started by a1ex, July 16, 2013, 06:33:50 PM

Previous topic - Next topic

0 Members and 3 Guests are viewing this topic.

sebamax

ISO 100 is better but the DR is much lower than dual ISO. Using ETTR: external exposure the shutter was 800 (ISO 100-F2.8) and internal exposure the shutter was 50 (ISO 100 F2.8).

a1ex


horshack

Quote from: sarangiman on July 18, 2013, 11:19:38 PM
But typical 'engineering' DR calculations using SNR of 1 as the lowest signal don't consider shot noise, correct? Therefore, one could still say that the engineering DR is extended to FWC/read noise @ISO 1600, which is ~14EV. If you're using a lower SNR cutoff of, say, 20, then the DR is much more modest (considering the increase in shot noise contributions you mention).

Right, SNR goes down but if one uses a 1:1 SNR (like DxO does) for DR calculations then then SNR reduction doesn't affect the DR number.

Danne

A little testing with the dual iso feature. Real cool stuff going on. Feel free to comment.


//D

Danne

Quote from: sebamax on July 19, 2013, 07:31:19 PM
ISO 100 is better but the DR is much lower than dual ISO. Using ETTR: external exposure the shutter was 800 (ISO 100-F2.8) and internal exposure the shutter was 50 (ISO 100 F2.8).

I don,t quite get this. Clearly you get the best results here in your movie "iso 100 raw expo internal ettr raw2dng".
Could you explain what your settings were exactly.
Thanks!
//D


driftwood

bright3 better edge. check the curvature of the lamp. bright1 inconsistent. bright2 good balance.

Yep for me bright3 detail wins (see blind edges too). bright1 slightly better in highlight detail - see blind chord. (right click images into new window to analyse). bright2 somewhere in the middle.



Canon 60D, Canon 5DMK3, Lexar 1000x 128GB CF, Panasonic (shhhh!) GH2s & GH3s. :-)

Danne

I think bright 1 is nice. The blinds seem smooth and the camera is less aliased than the others.

Audionut

For the window, bright 1.  Smoothest edges, least artifacting.

For everything else, bright 2.  Bright 1 is a no show, to much aliasing. 

Bright 3 has more artifacts.  Check the difference between 2 and 3 on the full res samples in the areas I have highlighted below.


Canon eos m

Hi,

Thank to Audionut for supplying the binary install for the dual iso module. Uploaded and now sailing to go. Facing a challenge though and need desperate help. The raw2dng that I downloaded cannot be activated since windows 8 sees it as a threat if some sort and is locking it on my PC. Any idea how to deactivate the security to get the program running?

Second, how do I record stills with the dual iso module? Cold someone post the workflow?

Thank you again and to A1ex too.
Canon 5D Mark III, Gopro Hero Blacks with 3D Casing, A Few Lenses, Adobe CC 2014, MacBook Pro, Windows 8 PC, Lots of Video Rig!

Started Nuke. Loved it but then the 15 day trial ran out. Back to After Effects and loving it :-)

sebamax

Quote from: Danne on July 19, 2013, 10:37:26 PM
I don,t quite get this. Clearly you get the best results here in your movie "iso 100 raw expo internal ettr raw2dng".
Could you explain what your settings were exactly.
Thanks!
//D
Hi,
I wanted to try an extreme situation of light.
In the first shoot with the raw module and ETTR module, I pointed out of the window and ETTR suggested me ISO 100-shutter 1.000 F2.8. In the second shoot I pointed inside the room: ISO 100 shutter 60- F2.8.
With dual ISO module (ISO 100-1.600) with ETTR I pointed out of the window and it suggested me ISO 100 shutter 800-F2.8. I processed all in ACR using Highlight -100 and shadow +100.
With dual ISO module it was a little bit difficult using viewfinder to focus.



sebamax


Canon eos m

Canon 5D Mark III, Gopro Hero Blacks with 3D Casing, A Few Lenses, Adobe CC 2014, MacBook Pro, Windows 8 PC, Lots of Video Rig!

Started Nuke. Loved it but then the 15 day trial ran out. Back to After Effects and loving it :-)

Canon eos m

A1ex: How do I take still with the dual_iso functionality?
Canon 5D Mark III, Gopro Hero Blacks with 3D Casing, A Few Lenses, Adobe CC 2014, MacBook Pro, Windows 8 PC, Lots of Video Rig!

Started Nuke. Loved it but then the 15 day trial ran out. Back to After Effects and loving it :-)

a1ex

To take stills, press the shutter button, then read the first post. Picture quality should be RAW.

So... you all say it's better to have sharper false detail and aliasing artifacts?

To me, it seems better to have less artifacts, even if the highlights are softer. I've updated the converters with the new algorithm, it should print "mean23-vsmooth3". Can you run some tests?

jaybirch

Quote from: a1ex on July 20, 2013, 12:23:02 PM
To me, it seems better to have less artifacts, even if the highlights are softer.

100% Agreed.

Softer images, i can work with. Noticeable artefacts are a no go.

Danne

My vote for the smoother picture with less artefacts definitely.

Stedda

5D Mark III -- 7D   SOLD -- EOS M 22mm 18-55mm STM -- Fuji X-T1 18-55 F2.8-F4 & 35 F1.4
Canon Glass   100L F2.8 IS -- 70-200L F4 -- 135L F2 -- 85 F1.8 -- 17-40L --  40 F2.8 -- 35 F2 IS  Sigma Glass  120-300 F2.8 OS -- 50 F1.4 -- 85 F1.4  Tamron Glass   24-70 2.8 VC   600EX-RT X3

Canon eos m

Canon 5D Mark III, Gopro Hero Blacks with 3D Casing, A Few Lenses, Adobe CC 2014, MacBook Pro, Windows 8 PC, Lots of Video Rig!

Started Nuke. Loved it but then the 15 day trial ran out. Back to After Effects and loving it :-)

Canon eos m

Canon 5D Mark III, Gopro Hero Blacks with 3D Casing, A Few Lenses, Adobe CC 2014, MacBook Pro, Windows 8 PC, Lots of Video Rig!

Started Nuke. Loved it but then the 15 day trial ran out. Back to After Effects and loving it :-)

jaybirch

Starting to get close to a usable settings. This was shot ISO 200-800 .... Exposure was pretty centred, to avoid too much highlight aliasing. Click for 1080p


a1ex

Yes, that's the ideal use case. Main subject covered by both ISOs (full detail), highlights and shadows as out-of-focus backgrounds (no aliasing).

jaybirch

yep... I did a rack focus and once the highlights come into focus, it gets a bit messy, but not too bad.

For now, i think protecting the highlights as much as possible is the best way to go, avoiding artefacts.... Then pulling out the deep shadows. Probably not getting quite such a DR boost, but it gives a more usable image.

GregoryOfManhattan

yes - good to know better use cases may not be the extremes and
to consider the value (thematically and exposure wise) of what's in field of focus.

is raw2dng in unified supposed to be able to process dual iso clips?
tried 5bad65ff8cb8 and it isn't converting a dual shot clip - instead it creates banded DNGs.

easy enough to download a different version.