Author Topic: Orion Nebula in 4K HDR  (Read 259 times)

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MarkS

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Orion Nebula in 4K HDR
« on: Feb 26, 2020, 09:11:24 »
I've found a way of converting images to high dynamic range (HDR) mode on a 4K HDR TV.  They need to be converted to 10-bit HDR video to trigger HDR mode.

Here is an example uploaded to YouTube:
https://www.youtube.com/watch?v=e5ElRam1hZQ

It will look very underwhelming on a normal TV or computer display but using the YouTube app on a 4K HDR Smart TV it should automatically display in HDR mode (the 2160p 4K quality option).  It will be obvious because the stars suddenly look intensely bright.  As with all HDR content, it is best viewed in a dimly lit or darkened room.

A better quality version (orion_nebula_4K_HDR_v2.mp4) can be downloaded from here:
https://drive.google.com/file/d/1CvcUUeW_UjP_DHcJcIYK1IcQENia1WHh
You can then play it directly e.g. on a USB stick. Ignore the washed out preview that Google Drive provides.

The relative brightnesses of every part of the scene are correct i.e. this is a deliberately unstretched image.

Enjoy!

Mark

P.S.  I'm giving a talk at the Ashford Astronomical Society on Friday about colour in the universe.  Unfortunately I won't be able to display that image in HDR.

« Last Edit: Feb 26, 2020, 09:40:06 by MarkS »

Carole

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Re: Orion Nebula in 4K HDR
« Reply #1 on: Feb 26, 2020, 10:24:44 »
I can see the brightness but son;t have the components to see it at it's best.

Reminder, since you don't have a diary Mark, OAS Meeting and AGM this evening.  You need a calendar, I will bring some.

Carole

MarkS

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Re: Orion Nebula in 4K HDR
« Reply #2 on: Feb 26, 2020, 12:59:44 »
Quote from: Carole
Reminder, since you don't have a diary Mark, OAS Meeting and AGM this evening.  You need a calendar, I will bring some.

I'll be there.  You'll be able to see my "Frankenstein" hand!

Mark

Carole

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Re: Orion Nebula in 4K HDR
« Reply #3 on: Feb 26, 2020, 15:39:42 »
Oh dear is it that bad?

Carole

RobertM

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Re: Orion Nebula in 4K HDR
« Reply #4 on: Feb 26, 2020, 19:10:25 »
Oh dear is it that bad?

Carole
I would run if he starts singing Monster Mash :o

Carole

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Re: Orion Nebula in 4K HDR
« Reply #5 on: Feb 27, 2020, 09:18:55 »
Excellent operative result on Mark's hand, saw it last night. 

Carole

RobertM

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Re: Orion Nebula in 4K HDR
« Reply #6 on: Mar 01, 2020, 11:00:15 »
Just played the HDR version on the telly and I can see that you’ve just managed to resolve the trapezium as well as displaying all the background dust clouds.  That’s a nice result for an unstretched image but a shame it has to be shown as a video; is there anyway around that ?

Thanks for sharing
Robert

MarkS

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Re: Orion Nebula in 4K HDR
« Reply #7 on: Mar 01, 2020, 14:33:40 »
Agreed, it is a great shame it has to be shown as a video.  It appears to be a design decision to restrict HDR to videos adhering to the HDR standard i.e. 10-bit videos using the Perceptual Quantizer (PQ) transfer curve in the Rec2020 colour space.  I have created an AdobeRGB JPG of the same data but it really doesn't have the same impact because without HDR the stars no longer have the same intense brightness - in fact the whole image is darker.  I guess we'll have to wait until an HDR static image format is commonplace.  But I see no reason why a TV shouldn't be able to display 16-bit TIFs since they can be easily generated by most raw convertors and Photoshop/RawTherapee.  Admittedly the TIF format is a can of worms with many variants but why can't they agree to support a certain subset?

If you're interested in the technical details of producing such an HDR video from an image, they are here:
https://www.cloudynights.com/topic/695780-orion-nebula-in-natural-colour-4k-hdr/?p=10006031

Mark
« Last Edit: Mar 01, 2020, 14:47:50 by MarkS »

RobertM

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Re: Orion Nebula in 4K HDR
« Reply #8 on: Mar 01, 2020, 19:40:35 »
Thanks Mark.  Will investigate further when I've a bit more time on my hands.

Thanks
Robert

MarkS

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Re: Orion Nebula in 4K HDR
« Reply #9 on: Mar 01, 2020, 23:35:17 »
If you are interested, here is the 4K HDR video of a sunset image:
https://drive.google.com/open?id=1pWbQsfY1IFiFhuDkQMVQU5pi9HueCNDh

On an HDR TV in a darkened room, the sun is so bright that you will need to shield your eyes to cut out the glare in order to see detail in the shadow areas - just like being there in real life.

Mark
« Last Edit: Mar 01, 2020, 23:49:35 by MarkS »

Fay

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Re: Orion Nebula in 4K HDR
« Reply #10 on: Mar 12, 2020, 18:06:03 »
Really nice Mark. you do keep yourself busy!!!!

Fay
It is healthier to be mutton dressed as lamb, than mutton dressed as mutton!