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HDR Photo stack v Video stack experiment with the Q

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#1 emh52

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Posted 16 June 2019 - 12:55 PM

With the nearly full Moon last night I finally got around to a little experiment to directly compare a photo HDR stack with a video stack. Using the Q3.5 with an inline 1.4X teleconverter and a Nikon D850 to fill as much of the full frame as possible a series of HDR images were acquired ( 9 X 0.3 stop) and mp4 video. Using Lynkeos to stack 3 X 9 X 0.3 NEF images converted to Tif were stacked to create one image and 2400 frames of video were stacked to create the other.  Both stacks were processed lightly with Lucy Richardson in Lynkeos before converting to a TIF. The TIF  individual stacks were further processed using Photoshop and Nik filters.

The two images were adjusted to the same resolution before grouping and posting.

 

Full resolution of the image is at  https://flic.kr/p/2gf86Fi

 

Both images are detailed with some subtle differences between them. To my eye the video stack is slightly sharper but the HDR shows more subtle detail especially in the darkest areas of the Lunar disk.

Attached Thumbnails

  • Moon HDR v Video.jpg

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#2 JamesMStephens

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Posted 16 June 2019 - 02:31 PM

This is an interesting experiment.  I think the contrast is greater in the video image.  They're both nice!

 

Jim


Edited by JamesMStephens, 16 June 2019 - 07:53 PM.

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#3 ScottAstroNut

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Posted 16 June 2019 - 05:10 PM

They are both great images! The differences are subtle. 



#4 RobertPettengill

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Posted 17 June 2019 - 12:11 AM

I don't understand the purpose of the HDR stack with the full moon which has very little dynamic range?  An 8 or 10 bit video codec probably captures all of the range that is there.

 

You might also want to compare your 4k video capture stacking results with stacking higher resolution still images.  With the D850 and the teleconverter you should oversample the Quesar's resolution and get every detail possible out of the Q.


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#5 emh52

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Posted 17 June 2019 - 03:06 PM

I think there is a bit more dynamic range to be had for a quarter Moon or when the terminator is visible (shown)   and  https://flic.kr/p/2g5WyLJ - this is another HDR of 27 images showing a lot of detail in the full resolution, but I have also stacked 50-100+ images. I am sure I'll get around to a mega stack of stills v video sometime soon. All work well and all probably push the resolution of the Q.  It would be more interesting to photograph Sunspots.... but we are in a bit of a drought for a while- The important thing is to have fun- and enjoy the view through the Q.

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  • half moon.jpg

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