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

[Audionut]

Would be very nice if you can upload some DNG files (or CR2 if you still notice aliasing artifacts).

Aliasing seems under control these days.  Mainly false colors.


There is a little aliasing on his left elbow.

[Danne]

@Audionut. Is it green fringing? Could it be removed in lighroom?

[Audionut]

Yeah LR does remove it.  It requires fairly heavy defringing though which can cause artifacts.

[Danne]

I see. Nice work, Looking forward to more examples using this great function

[Danne]

@Alex. I uploaded three cr2 with smaller issues on them. I don,t expect anything, think it works good as is. Provided in the link three cr2-files and a word-document with issuedescription.
https://docs.google.com/file/d/0B4tCJMlOYfirc1NZbVhJR2tMNHM/edit?usp=sharing
Thanks Alex
//D

[arrinkiiii]

It's a bird? It's a aeroplane? It's a bulldozer?  NO! Its A1ex and the rest of the ML gang    

BIG THANK YOU for fixing the 70error for the 7D.




-7D IS BREATHING AGAIN -

[pit3k]

Quick test for sharpness: 100% middle crop of 7d with 17-55/2.8. 17mm @ 2.8

No dual iso (iso 100):



Uploaded with ImageShack.us

Dual iso 100/1600:



Uploaded with ImageShack.us

cr2 and raw files: https://www.dropbox.com/sh/tw3lo4kblurabkn/zjZGCfABR5

[a1ex]

That's why you should try to cover your main subject with both ISOs, and keep the extra range for highlight/shadow recovery (e.g. detail in clouds).

[pit3k]

That's why you should try to cover your main subject with both ISOs, and keep the extra range for highlight/shadow recovery (e.g. detail in clouds).

I think in this situation this wasn't the case. Light was even on the desk with no over or under exposure.

I think the cr2hdr needs a little bit of tweaking to leave alone the mids, and work with only  highlights and shadows.

Or maybe its exposure problem. What is av mode exposing for, 100 iso? Shouldn't I expose for around 640?

[dubzeebass]

I wonder if the posts about how it looks too "HDR" are just because we're not used to this sort of latitude coming from the camera.  I was watching Ray Donovan last night and also True Blood a couple of nights ago and I paused a couple of times where there was a lot of DR in the scene and it frankly looks like HDR.

Both the Alexa and film shoot at 14 stops and pausing such an image looks like the HDR pictures from the camera.  Just my $0.02!

-Ben

[a1ex]

I think the cr2hdr needs a little bit of tweaking to leave alone the mids, and work with only  highlights and shadows.

Did you read my paper?

[pit3k]

Did you read my paper?

Now I have, my bad mate. Your work is amazing.

[stevefal]

It would be cool if the latest dynamic range features could be combined to provide a better and more convenient high-bit-depth still image. This maybe a blue-sky idea, but oh well.

First to clarify a term, "HDR" is casually used to describe two different things: 1) image data with high bit-depth (16+ bit) per channel, and 2) an image that was captured with high bit-depth and then compressed (curves, microcontrast etc), to reveal detail on low-contrast devices, sometimes with garish results - hence, "that looks unrealistic, like HDR".

Savvy photographers want the latitude of high bit-depth images in order to create the best possible result in post. So in-camera "HDR" features that generate an 8-bit JPEG from multiple exposures defeat the purpose.

Bracketing discreet still shots for the purpose of creating high bit-depth negatives in post is better, but the drawback is artifacts due to motion between shots.

So the question is, would it be possible to improve on the dual-exposure model by creating a new ML High-Range mode that does the following:

- shoot through viewfinder (ideally) a la still mode
- two iso-bracketed exposures during one shutter actuation - a la rawrec and miracle-happens-here
- two shots are combined in-camera - mids from first and highlights/shadows from second - kinda a la dual-iso modulo a1ex genius
- save 16-bit DNG that opens directly in ACR

This approach would have some drawbacks:
- lower still burst rate
- highlight/shadow artifacts due to motion

and advantages:
- pristine IQ for still scenes - no aliasing
- less severe motion artifacts than dual-shutter bracketing
- no workflow before ACR

versus current dual-iso advantages:
- higher burst rate
- no artifacts due to motion

and drawbacks
- always highlight/shadow artifacts due to interlace aliasing
- workflow steps before ACR

If the in-camera part was impossible or way too slow, combining could be done in workflow while keeping the IQ advantages.

[arrinkiiii]

Some tests

NORMAL




DUAL ISO



This is wanderful and never show up the 70error 

I see some things happen that i don't know if it's normal

1- Wend i back home to see the photos, i see in the structure of the CF card (in canon folders) that after i take a few photos he creates another folder and put the rest of the pictures there.

2-Wend i pick-up all the photos and drag to the cr2hdr, he fail always the first pictures. The rest of the pictures, he transcribe good and make the dng file. But almost in the end of each file, wend cr2hdr are doing is work, its show up a message saying that the exiftool didn't work, like the image below. Evan with this error the cr2hdr make is job and make the dng that i can open in photoshop for making the right tweek.





3- A problem that i come across is that is hard for make the right exposure.  Didn't, yet, get the best way to exposure.

4- Also noted that the photos make a strange border, but can be because of the jpg. I can crop wth no problem. Just for let you guys  know about this.


Beside this DUAL ISO is one more great function in the ML arsenal =D.

THANK YOUU !!!

[dubzeebass]

2-Wend i pick-up all the photos and drag to the cr2hdr, he fail always the first pictures. The rest of the pictures, he transcribe good and make the dng file. But almost in the end of each file, wend cr2hdr are doing is work, its show up a message saying that the exiftool didn't work, like the image below. Evan with this error the cr2hdr make is job and make the dng that i can open in photoshop for making the right tweek.

Try running cr2hdr in a directory with no spaces just off the root directory.  It works for me like that.  You'll see the weird letters; for some reason it doesn't like spaces in the directory name (exifinfo.exe).

[arrinkiiii]

Try running cr2hdr in a directory with no spaces just off the root directory.  It works for me like that.  You'll see the weird letters; for some reason it doesn't like spaces in the directory name (exifinfo.exe).

Much appreciated dubzeebass, thank you.

[Sky_cleaner]

Thanks to ALL for this wonderfull module - dual ISO! But how to work with resulted  .CR2   on Mac OS?  Can anyone help Mac users?

[dadinio13]

Somes tests again :

[xmd5a]

Here is a link to problematic cr2 (waves in the center of the picture painted in the colors of the rainbow)
https://dl.dropboxusercontent.com/u/4624786/_MG_8792.CR2

[a1ex]

This should help you understand better how it works and how to expose the pictures:

http://acoutts.com/a1ex/split_MG_8792.dng

[daancalo2013]

Here is a link to problematic cr2 (waves in the center of the picture painted in the colors of the rainbow)
https://dl.dropboxusercontent.com/u/4624786/_MG_8792.CR2

I am new but eager to aprendre, here I leave another example
http://we.tl/BeTdsXJe4G

[a1ex]

Here I'm afraid the only solution is to cover the palm trees with both ISOs. Remember that aliasing can't be removed in software (Nyquist theorem), only the artifacts can be somewhat masked.

[arrinkiiii]

Here I'm afraid the only solution is to cover the palm trees with both ISOs. Remember that aliasing can't be removed in software (Nyquist theorem), only the artifacts can be somewhat masked.

Quem sabe, sabe

who knows, knows

[sletts02]

Any video examples yet? It'd be great to see some =)

[arrinkiiii]

This should help you understand better how it works and how to expose the pictures:

http://acoutts.com/a1ex/split_MG_8792.dng

Undoubtedly that the picture from bottom have the right exposure. But how you get at that settings?  (7D)