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black and white point astro light pollution


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I would guess that for astrophotogaphy, the usual processes for black point (and possibly white point) do not apply, especially if you have light pollution. It woiuld help if you posted a typical astro-image with light pollution, along with a screenshot of the Curves panel. This would give us a better idea of how to deal with your images.

 

John

Windows 10, Affinity Photo 1.10.5 Designer 1.10.5 and Publisher 1.10.5 (mainly Photo), now ex-Adobe CC

CPU: AMD A6-3670. RAM: 16 GB DDR3 @ 666MHz, Graphics: 2047MB NVIDIA GeForce GT 630

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@newty, I tried to download your video and CR2 file, but both appear to have zero bytes. The html gives:

<a href="http://82.253.46.150/share/t3Qmge1oS0beK_qV/M42_LIGHT_750DT6i_1600iso_Tv20s_00092.CR2" rel="external nofollow noopener noreferrer" target="_blank">http://82.253.46.150/share/t3Qmge1oS0beK_qV/M42_LIGHT_750DT6i_1600iso_Tv20s_00092.CR2</a>

it specifies rel="nofollow noopener" which may be preventing my access.

Could you perhaps develop the CR2 with defaults file and export as a jpeg which should download readily. It may not be your definitive image, but it might give us an insight to your problem.

John

Windows 10, Affinity Photo 1.10.5 Designer 1.10.5 and Publisher 1.10.5 (mainly Photo), now ex-Adobe CC

CPU: AMD A6-3670. RAM: 16 GB DDR3 @ 666MHz, Graphics: 2047MB NVIDIA GeForce GT 630

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Recently, @Dingdong posted some astronomical images, including one of the Carina nebula. I downloaded this and looked at the Curves Adjustment, which looked like this:

Curves.png.cad11fbc9796228f4045b44f867f71f4.png

I brought the black point slider from the left-hand corner to the start of the histogram. I also brought down the white point slider to the right-hand edge of the histogram, as seen in the white line. This had a beneficial effect on the image (which I do not show as it is @Dingdong's).

I would suggest you try this on your images. Following the Levels Adjustment did not have such a beneficial effect as this.

John

Windows 10, Affinity Photo 1.10.5 Designer 1.10.5 and Publisher 1.10.5 (mainly Photo), now ex-Adobe CC

CPU: AMD A6-3670. RAM: 16 GB DDR3 @ 666MHz, Graphics: 2047MB NVIDIA GeForce GT 630

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Can you show it John?

 

I'll re-do it and try this also.

 

Newbie means Ive never edited an image until I did my first one of the Flame Nebula and the one you speak of. I have had Affinity Photo for over a year but have never used it until now. Any and all suggestions and advise i'll try and take on. I actually tried some editing on another unrelated image today after looking at Affinitys forums. The options seem endless which adds even more to the unknown world i'm finding myself entering.

 

This is exactly the reason I joined this and other forums...

 

Cheers John

 

D

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19 hours ago, Dingdong said:

Can you show it John?

D

Here is @Dingdong's original image:

Carina.thumb.jpg.6ac9deb668286f7d2bd1accdfd12bad0.jpg

This has had the Levels Adjustment as shown below:

CarinaLevels.thumb.jpg.86ffaa1bf26aa554b7c05d4a7c07a2f5.jpg

This shows the Levels Adjustment itself:

Levels.png.7ead4da3e30fea8bf4d000fbd14d1305.png

This has had the Curves Adjustment as shown below:

CarinaCurves.thumb.jpg.d6ebfd29ba71fbc6d1f2b7de2a8fd77d.jpg

This shows the Curves Adjustment itself:

Curves.png.c34712656c61a4927d87d06144e6e45a.png

John

Windows 10, Affinity Photo 1.10.5 Designer 1.10.5 and Publisher 1.10.5 (mainly Photo), now ex-Adobe CC

CPU: AMD A6-3670. RAM: 16 GB DDR3 @ 666MHz, Graphics: 2047MB NVIDIA GeForce GT 630

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7 hours ago, Dingdong said:

Any and all suggestions and advise i'll try and take on.

 

Hi,

 

If you zoom in on the darker areas of the image there's a lot of luminance noise: green and red speckles, for want of a better word, One of official Affinity tutorial videos shows a method of toning this down by converting the original to LAB colour and blurring the two colour channels. The relevant section of the video starts at around 6 minutes 30 seconds in. It's a fairly advanced technique, but I think when combined with a curves adjustment it can improve the (already amazing) image when viewed at full size.

 

5aa5a37f4098b_Carina.jpg.dee8a41e1271347d6c669d1c3c61e247(edit3).thumb.jpg.e018e604b8aaada08de8f8360d31c21e.jpg

 

 

Affinity Photo 2.0.3,  Affinity Designer 2.0.3, Affinity Publisher 2.0.3, Mac OSX 13, 2018 MacBook Pro 15" Intel.

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Hi

 

John

 

WOW it really does work and looks good too. Thanks

 

So far everything in astro forums seems to be based around PS, LR and the likes. I simply could not justify forking out the dollars and looked around to find Affinity Photo that ranked about ten in photo editing programs OTHER than PS - for Mac. But like all things cheaper you wonder if its gonna be a lemon... I'm glad I chose the software. As it is turning out, it is more than capable and the forums are full of all this wonderful stuff I never knew you could do. I thought I'd start an astro thread to see what others may be doing and how to do it - BOOM - its working.

 

Thanks again

 

h_d

 

My son used all my download and cannot watch the linked video but trust me I'll be looking as soon as I am able. There are a few methods in astro to reduce unwanted noise. But I think that the best way is to gather as much data of the noise you want which means longer or more exposures. Its great to learn of these new methods.

 

Thanks


Dion

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yes ...with level result its good ...

but is no "fix" as i want the black and white point as in video , IS it ?????

 

perhaps its the same thing ...i dont know

 

but in my case results whith level or "fix , pick" black and white

is not the same .....

and pick have been a best result ....

 

really thanks , perhaps i just a newbie

your job is very pretty good !!!!! hura

 

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Quote

If you create a rectangle filled with the colour (sampled from your image) that you want to become black, and another with the colour you want to become white, and then make them become black and white by manipulating a Levels Adjustment's black and white points for each channel, you'll do exactly the same thing as Photoshop does, except Photoshop has the convenience of the samplers in its levels adjustment.

amazing

1,  i have tried with  the "first method" resul ...good

2,  ok for AF not yet ...

3, your "quote" is very interessing

would you like to ....make an example , PLEASE

it seems to be THE !!! Solution  for me

 

very thanks

 

 

 

 

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9 minutes ago, newty said:

another time i have not be ...notified !!!!!!

 

What notification settings have you selected? You can choose to receive a notification when new content is posted in a thread to which you have posted, but (as I understand it) only if you have chosen to automatically ‘follow’ the thread.

Alfred spacer.png
Affinity Designer/Photo/Publisher 2 for Windows • Windows 10 Home/Pro
Affinity Designer/Photo/Publisher 2 for iPad • iPadOS 17.4.1 (iPad 7th gen)

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14 minutes ago, newty said:

hope have fixed it ....

 

I hope so too! Thanks for the update.

 

16 minutes ago, newty said:

great thanks

 

You're very welcome.

 

Alfred spacer.png
Affinity Designer/Photo/Publisher 2 for Windows • Windows 10 Home/Pro
Affinity Designer/Photo/Publisher 2 for iPad • iPadOS 17.4.1 (iPad 7th gen)

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