Simple UI improvement suggestion (correct exposures and colors)

[Abrimaal]

After 10 years of making panoramas in Hugin, I see that the most of panoramas look better (more naturally) without exposure correction.
Especially the sky and night scenes.

I suggest adding two optional steps in the Assistant preferences:
Correct exposures, correct colors,

without entering the Panorama editor to Reset.

In the main window of the Simple UI, two buttons
By default the panorama is built without photometric corrections.

[T. Modes]

Abrimaal schrieb am Montag, 11. Dezember 2023 um 01:20:18 UTC+1:

After 10 years of making panoramas in Hugin, I see that the most of panoramas look better (more naturally) without exposure correction.
Especially the sky and night scenes.

I suggest adding two optional steps in the Assistant preferences:
Correct exposures, correct colors,

without entering the Panorama editor to Reset.

I see the opposite. For me the panoramas become significant better with photometric corrections.

[David W. Jones]

I generally see that, too, although it depends on the source images. But I generally try to do exposure correction (if any) in the source images. I think it avoids the occasional situation where Hugin maybe gets confused when the images have a wide range of exposures and/or color temperatures?

There's one situation where Abrimaal's idea makes sense for me: when using 16-bit HDR source images. I don't do any exposure corrections in the source images, just take them as the camera produced them. Then I use Hugin to stitch the images into an EXR panorama and process that in Luminance HDR. So I don't need or want exposure correction for the source images.

Now, how does this connect with the Assistant? I usually follow a manual process (align, clean control points, next step of aligning, clean, etc) for aligning images. In some cases, I've been unable to get an aligned panorama out of the set that way. But in many of those cases, starting from scratch using the Assistant produces a nicely-aligned image - only with the photometric corrections I don't want.

While that can be cleared in Hugin, it might be nice to have an option to turn it off in the first place? Or is that something that could be done in a modified Assistant script?

-- 
David W. Jones
gnome...@gmail.com
authenticity, honesty, community
http://dancingtreefrog.com
"My password is the last 8 digits of π."

[T. Modes]

GnomeNomad schrieb am Donnerstag, 14. Dezember 2023 um 00:59:13 UTC+1:

There's one situation where Abrimaal's idea makes sense for me: when using 16-bit HDR source images. I don't do any exposure corrections in the source images, just take them as the camera produced them.

What (consumer) camera produces HDR images straight out of the cam?

[Paul Womack]

Nikon D850 - 14.8 stops off the sensor. Don't know how many bits it uses to represent that.

--
A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ
---
You received this message because you are subscribed to the Google Groups "hugin and other free panoramic software" group.
To unsubscribe from this group and stop receiving emails from it, send an email to hugin-ptx+...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/hugin-ptx/9f9206f0-dfcb-4fad-8326-27c5945940f8n%40googlegroups.com.

[David W. Jones]

My old Minolta Maxxum 7D's camera provided 12-bit color in its RAW format, using the camera's 12-bit ADC.

My current Sony SLT-A58 specifications report 12-bit color in RAW, too. Although I'm puzzled. I found a page about it at Imaging-Resource.com that mentions "DxO" scores(?) for the sensor. They report color depth score of 23.3 bits and a Dynamic Range Score of 12.5EV...

I suppose it depends on your definition of HDR, but my understanding is that HDR is 16-bit or higher... My thought on it is "HDR" is anything higher than 8-bit per color channel, so the common television HDR10 standard is HDR.

Ideas?

On 12/14/23 08:56, Paul Womack wrote:

Nikon D850 - 14.8 stops off the sensor. Don't know how many bits it uses to represent that.

On Thu, 14 Dec 2023 at 15:39, 'T. Modes' via hugin and other free panoramic software <hugi...@googlegroups.com> wrote:

GnomeNomad schrieb am Donnerstag, 14. Dezember 2023 um 00:59:13 UTC+1:

There's one situation where Abrimaal's idea makes sense for me: when using 16-bit HDR source images. I don't do any exposure corrections in the source images, just take them as the camera produced them.

What (consumer) camera produces HDR images straight out of the cam?

-- 
David W. Jones
gnome...@gmail.com
wandering the landscape of god

[Paul Womack]

I would take a big money bet that the still camera world's definition of HDR (formal or implicit) is different to the TV/Film world's.

Just to make life difficult for everyone.

--

A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ
---
You received this message because you are subscribed to the Google Groups "hugin and other free panoramic software" group.
To unsubscribe from this group and stop receiving emails from it, send an email to hugin-ptx+...@googlegroups.com.

To view this discussion on the web visit https://groups.google.com/d/msgid/hugin-ptx/8c372a71-d201-48f7-9f00-b8a27f090a85%40gmail.com.

[Gunter Königsmann]

My cameras all seem to have a Bayer Colour Filter Array with 1 Red Filter, 1 Blue Filter and 2 Types of green Filters that each filter different parts of the light spectrum.If one photo uses one of these green filters and for the next one the camera decides to use the other photometric optimization cannot help too much: For some pigments and dyes both filter will result in exactly the same colour, while for others the coklors thw camera sees will differ greatly.

Might this be the underlying problem?

[David W. Jones]

Well, start with Wikipedia:

https://en.m.wikipedia.org/wiki/High-dynamic-range_imaging

I use EXR format by preference, that came from the TV/movie world.

Then you get to astronomical digital imaging. They don't use Bayer type sensors. They use sensors that read only brightness levels, and physical filters to change the frequency of light that hits the sensor. Or something like that.

exploring the landscape of god
http://dancingtreefrog.com

Sent from my Android device with F/LOSS K-9 Mail.

[T. Modes]

GnomeNomad schrieb am Freitag, 15. Dezember 2023 um 00:33:50 UTC+1:

I suppose it depends on your definition of HDR, but my understanding is that HDR is 16-bit or higher... My thought on it is "HDR" is anything higher than 8-bit per color channel,

yes, a HDR image is 16 bit or higher. But the reversal is not valid: a 16 bit image is not automatically a HDR image. There are also 16 bit LDR images.

[Gunter Königsmann]

For my microscope a few months back I bought a (cheap) astronomical camera that uses a Bayer array: the microscope produces an intermediate image with parallel rays that then is viewed using a telescope and since light constantly rips electrons from chemical bonds and therefore much light eventually kills what you are looking at one needs a camera that is able to deal with dim light. I guess astronomical devices should not spontaneously change the spectrum of their colour filters between two measurements, though.

But last night I remembered something different:
I once had a camera that had not a bad pixel, but a bad spot that wasn't big - but caused the photometric optimization to go wild: In one picture there was a gray spot where in the next picture was red, green, blue or something else.

Kind regards,

  Gunter.