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First post here.  I've been working on a composite of images captured during totality & getting some banding artifacts in PS when forced to use 16 bit mode rather than 32 bit for sharpening steps.  I'd like to make sure Affinity Photos has the adjustments I need in 32 bit mode.  The complete workflow for PS is describe in this tutorial by Russell Brown: PS Spin Blur Eclipse Processing

 

From Photos tutorials, I see there are spin-blur filters, Apply Image: Equations panel & an Equations panel.  So maybe everything I node is there but done differently in Photos.  The key step I'm unsure about is in one of the equations panels.  In PS, a duplicate image is spin blurred & the alpha channel of that image is subtracted from the original alpha w/ an off-set of 128 in the Calculations panel to give a low contrast mid-gray frequency mask.  That mask is then Overlayed onto the original.

 

I'd like to confirm that all this can be done in Photos in 32 bit mode?

 

Here is a version of my PS work from 77 images w/ artifacts & a mask.  The frequency mask reveals the finer corona detail.

 

Thanks!

14xWithBanding.jpg

FrequencyMask.jpg

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Sorry, I don't know enough to help you!  That's a great image of the corona, but I'm intrigued by the pink spots - were some of those 77 images taken in H alpha?


AP user, running Win10

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Thank you.  The exposures range from 1/4000 to 4".  The pink spots on the moon are caused by lens flare from the red prominences on the solar surface in the long exposures.  This particular approach to post processing this mother of all HDR can not reveal the prominences against the super bright inner corona so all that can be seen is the flare.  Several additional steps will be needed to tease out the prominences.

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Got it, thanks.

 

Have gotten to compare my images to others today & the impact of smokey air I had is starting to look like the main cause of the banding artifacts I'm getting.  Not sure what do do about that.  

 

I'll give a demo version of AP a spin to see if it helps.

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I am a newbie, both to Affinity Photo and to advanced eclipse processing.  I have been struggling to use the Russell Brown method to process some 18 images of the corona that I managed to capture, without success.  owenr, I would appreciate any tips you can provide on how to do it in Affinity Photo.  Thanks.

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I've learned lots that I can add.  Depending on your 18 images, some of Browns recommendations are just plain wrong - namely strong pre-processing adjustments & especially 60+ Clarity. But then he never mentions the need to stay in 32 bit mode.  My images (I'm using 77) were shot through light smoke so I have daunting light scatter problems that lead to banding in the sky.  

 

Image alignment is probably something you are struggling w/.  Of course the lunar disk & sun are not moving together so the lunar disk will be miss aligned when the corona & prominences are aligned.  The best tip I have there is use a Levels Adj layer at the top of the stack to increase the contrast in the difference images.  When aligning images at different exposures, you need to adjust the Level so that the increased contrast occurs in the overlap region of the difference image.  If you have big bright Regulus in your images, you can use that for alignment.  

 

OWNER, question for you.  Can Photos be set to move images in sub-pixel amounts?  PS goes 1 pixel each time the arrow key is tapped.  Sometimes sub-pixel alignment is needed w/ these images.

 

Here's the best I've gotten so far out of PS & am about to give Photos a try.

14Flat32AdjAlignedCropped.jpg

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I’ve been playing with the radial blur technique on some images from the July 2, 2019 eclipse in South America using the affinity photo iPad version

 

First , I’ve empirically found that using a 10-20 angle on the blur result in very little or no effect

when I bump the angle up higher 30,60 even 90, then I start to see a significant effect

With a 90° angle I get a decent result, but only in one plane, X or Y, depending on whether I choose S-D or D-S

I’ve included an image of the original , S minus D, D - S and then the composite of the two ( brightened a bit)

I did not add the 128 offset which would lighten up the results overall

I understand that I am supposed to use the original minus the blur as an alpha layer on the original, not ready for that yet

If anyone can explain why I get the results I do as opposed to the people using PS w 10 or 20° radial blur

id appreciate comments and pointers

thanks

257F11D4-D201-407C-97D0-F2AB7B7FBDB0.jpeg

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Well - after some trial and error, I realized that the 128 “offset” referred to in the various photoshop tutorials, is equivalent to 0.5 in Affinity-land, which makes sense in retrospect. So the Apply image equation is D = D - S + 0.5  ( using DR,DG,DB etc)

 

As a test, I took 3 images and applied the radial blur method. Below is the series of 4 steps for one single component image, then the composite of all 3

it’s a little crude, but now I can refine the process using 7 images from a bracketed sequence . This was done on an iPad:

 

 

 

03F615D1-5032-4D61-8462-E9BFBA79B349.jpeg

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marcr1230, keep at it.  I worked on my images several times to exhaustion & would stop for long periods & come back to them.  Took maybe 5 try before I figured out what works.  The breaks help refresh you & encourage insight that leads to new progress.  I've done lots of astro but nothing comes close to the demands of processing a eclipse @ totality. 

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