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willcastle

What the hell. I’m so confused.

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On 29/01/2020 at 16:28, vlaiv said:

Do you mind posting original sub, unless that exact jpeg came out of the camera?

Fact that above image is 1920x1280 means that either you or camera made image smaller. If this image as is came from camera - then Canon probably implemented very nice way to reduce image size - use of algorithms similar to binning.

Additional thing that can happen is jpeg smoothing. In any case, combination of those parameters could make image look as x10 longer exposure, so image was not in fact 11s but about 110 seconds.

Still impressive result.

IMG_2176.CR2

hey vlaiv, here is the original RAW file at 6000x4000 33.2 MB

I don't know if it will display (being a raw file)

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4 hours ago, willcastle said:

IMG_2176.CR2 33.28 MB · 2 downloads

hey vlaiv, here is the original RAW file at 6000x4000 33.2 MB

I don't know if it will display (being a raw file)

You must have amazing skies where you shoot - very dark.

I was at first baffled of how you managed to get such a shot, but then I did some calculations and in fairly dark skies it is possible to have a glimpse of Running man in 11s exposure with this gear.

Fact that you took a jpeg image and it is only 1920x1280 helps a lot to get that level of detail and relatively nice looking stars.

Please don't take what I'm about to show you as taking a stab at your original image or anything. I'm just doing this to show how much both processing but also presenting image at certain scale can help make image look nice.

image.png.83d9039bc3bc70733ce39865164cc3d6.png

Here is a piece of original raw image showing couple of stars. At this scale we can't really say they are nice looking stars - they look more "pacman" like. But you don't need to show your image at that scale - you can bin your data (similar to resizing down - same thing that your camera did when converting to 1920x1280 jpeg) and then stars no longer look out of shape:

image.png.e2c11b19614c91a0f0de7c8bc2443c96.png

Now those same stars don't look out of shape any more (this above image is what you get when you reduce image size to 1500 x 1000 - or about x4 less than original resolution).

Let's now look at what Running Man looks in blue channel in original resolution:

image.png.62831113767fbfee1bc1f86905e8405d.png

Hm, nothing much there, is it? Just noise, and some more noise. But bin that and smooth it out and you will actually start to see the shape of it.

Here is what I've got as synthetic luminance from that single sub, after I did both binning and noise removal:

luminance.thumb.png.4b1ed49337207b02bd7dc19837ee10ec.png

Looks rather good? So yes, data is there and if you know how to process it you can extract quite a bit out of it.

People that work at Canon and with other companies that make cameras are in fact experts in data manipulation and no wonder automatic Jpeg from camera almost looks as good as this image above. Data is in fact there - and I believe in great part due to dark skies at site this was taken at.

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There's no feeling quite like it, is there?

I offer both my congratulations as well as commiserations for getting the photo bug. :) 

Joking aside; it IS a crack shot. You have every reason to be proud and happy about it.

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Congrats on an excellent first image.

Fast forward another 4-5 years into the future and you will be waiting for another 10 hours of Ha data to finish off an image that you can't shoot at the moment because the moon is too bright.

It starts off small, but then the desire increases.  😀

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