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Clavius 2021 process. From 2016


neil phillips

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Joined 4 avis together using PIPP and stabillized. total frame count 32000. Stacked 900. Did a 150% drizzle Auto stakkert. Box size 24.

Registax linear top wavelet only. Further  sharpening and noise reduction image analyzer. Light level adjust image analyzer. Not as natural perhaps as the original. But showing a touch more detail maybe in certain areas ? still like the dark and moody original mind.

What a large mass produced chinese Newtonian can achieve. The best capture i ever got. The scope cost me £100 SW 300P

ASI 290m camera. Neq6 mount. Altair planet killer IR Filter

Wonder what size craters i am getting down to on this ? Notice how not worrying about smoothness as a goal driven pursuit. It is allowing it to take on a fine sandy appearance. This is not possible with over smooth processing. Or at the very least very difficult. I miss that old scope

Top image 150% drizzle SGL Resizes this to around 200% as a guess ? 

Bottom image pushed harder (not as natural ) 100% SGL Resized to 150% as a guess. 

Clavius reprocess.png

 

100.png

Edited by neil phillips
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18 minutes ago, CraigT82 said:

Fantastic Neil, I think I prefer the second one

Interesting Craig, thank you for giving me your honest veiw. I wonder a lot about perceptions. I prefer the top. there is less detail but has that slight natural softness, so many including me try to achieve. There is no wrong and right. Different strengths and weaknesses In both approaches. Thought i had lost this footage. i reprocessed it on here a while ago. But that was just levels from a tiff. More interesting from scratch. And actual ser files. More control of any outcome

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Absolutely Neil, so many differing opinions on what makes a great lunar image it is impossible to please everyone.  I actually think that something halfway between the first and second image is what, for me, would be perfect. 

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I see no major difference between the two. Second one is just a bit more aggressively sharpened - and that is good, but if you resize them to the same size - they are virtually identical (nothing gained by drizzle).

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30 minutes ago, vlaiv said:

I see no major difference between the two. Second one is just a bit more aggressively sharpened - and that is good, but if you resize them to the same size - they are virtually identical (nothing gained by drizzle).

True to a degree. But more aggressive sharpening certainly can make small detail far easier to see. I have had many instances where i have under sharpened, and the small fine detail is impossible to see. Only with more sharpening did the detail become more apparent. If your suggesting more sharpening can not reveal more detail. I politely disagree. Its very easy to prove this is so. if i redo a version of this and use 2 on the top registax wavelet scale. Highlight a area were the detail is borderline to the eye. Then do the correct amount  of sharpening to allow that borderline detail to be seen. The detail in the under sharpened image will be totally missing.  Infact think i am seeing this effect here. Without having to under or over sharpen to prove it ? Btw  drizzle or resizing can make separation easier to see too

Edited by neil phillips
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3 minutes ago, neil phillips said:

True to a degree. But more aggressive sharpening certainly can make small detail far easier to see. I have had many instances were i have under sharpened, and the small fine detail is impossible to see. Only with more sharpening did the detail become more apparent. If your suggesting more sharpening can not reveal more detail. I politely disagree. Its very easy to prove this is so. if i redo a version of this and use 2 on the top registax wavelet scale. Highlight a area were the detail is borderline to the eye. Then do the correct amount of of sharpening to allow that borderline detail to be seen. The detail in the under sharpened image will be totally missing.  Infact think i am seeing this effect here. Without having to under or over sharpen to prove it ? Btw  drizzle or resizing can make separation easier to see too

Since you posted two images - I just compared the two - did not mean to imply anything.

I just did this in my browser (these are respective screen shots - one scaled to 67% its size and other at 100% that way they match in pixel scale)

Stack.gif.37ba1d5d63a36ac7a5d6c8844ca609da.gif

Maybe I just wanted to point out that there was no real need to drizzle as it did not contribute anything - in fact, more aggressive sharpening creates better image.

I did not analyze sampling rate and pixel scale. Could be that image is over sampled as ringing is visible (consequence of wavelets / sharpening).

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Fair enough. But dont forget by downsizing the drizzle you are negating any effect or separation improvements to the eye gained by drizzling ? ( especially these old eyes)

Agreed separation of close fine detail isnt really showing ( at full size differences ) in these examples. But i strongly suspect it could on occasion with the right data, and two points being hard to separate by eye.

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1 minute ago, neil phillips said:

Fair enough. But dont forget by downsizing the drizzle you are negating any effect or separation improvements to the eye gained by drizzling ? ( especially these old eyes)

Agreed separation of close fine detail isnt really showing ( at full size differences ) in these examples. But i strongly suspect it could on occasion with the right data, and two points being hard to separate by eye.

In order for drizzle to have any chance of bringing improvement - you need to under sample to begin with.

What F/ratio were you using for ASI290?

In any case - here is non drizzled version upscaled to drizzled version and again - blinked:

Stack-1.gif.92f6de968bf6928d23d8f764520f4395.gif

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2 minutes ago, neil phillips said:

What bugs me is if i put up a 150% resize. Why does SGL Software resize it to more like 200% ? losing the balance i was trying to achieve ?

SGL just scales image depending on screen size (smaller on thread page and a bit larger in image display page).

You can always open the image in separate window (right click - open link in new tab) and look at it at 100% zoom level.

That is how I usually look at all images - at their proper resolution and not scaled.

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3 minutes ago, vlaiv said:

In order for drizzle to have any chance of bringing improvement - you need to under sample to begin with.

What F/ratio were you using for ASI290?

In any case - here is non drizzled version upscaled to drizzled version and again - blinked:

Stack-1.gif.92f6de968bf6928d23d8f764520f4395.gif

Now your making any separation gains to the eye identical but doing it in reverse the result will be the same. Nothing

It was a long time ago i never kept the stats. Often i would put in tube extenders for more Focal length. So am unsure of the exact focal length ? 

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15 minutes ago, neil phillips said:

Now your making any separation gains to the eye identical but doing it in reverse the result will be the same. Nothing

It was a long time ago i never kept the stats. Often i would put in tube extenders for more Focal length. So am unsure of the exact focal length ? 

Rough measurement gives ~ 0.12437"/px

That in turn gives 4810mm of focal length with 2.9µm pixel size. 305mm is aperture, so effective F/ratio is ~F/15.772

You were using IR pass filter with 685nm cutoff frequency.

I'd say that you are roughly twice over sampled - but we can calculate it more precisely.

Indeed, critical F/ratio for this combination is ~ F/8.47 - almost the half of what you used.

Not only that you don't need to drizzle - you can in fact bin your data x2 :D

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1 minute ago, vlaiv said:

Rough measurement gives ~ 0.12437"/px

That in turn gives 4810mm of focal length with 2.9µm pixel size. 305mm is aperture, so effective F/ratio is ~F/15.772

You were using IR pass filter with 685nm cutoff frequency.

I'd say that you are roughly twice over sampled - but we can calculate it more precisely.

Indeed, critical F/ratio for this combination is ~ F/8.47 - almost the half of what you used.

Not only that you don't need to drizzle - you can in fact bin your data x2 :D

Your certainly one for numbers Vlaiv. But yes your correct i likely was oversampled. I was using lots of different combinations back then 3 or 4 different cameras

I should probably have thought a lot more about Focal length. Its something i will be thinking about when i start hi res again. Infact i was calculating this recently for when i start hi resolution again. Some have even suggested like Christophe Pellier that oversampling isnt always all bad. But i will leave that for others to debate. Certainly when i start again i will be thinking a lot more about What camera i am using with any particular focal length. 

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I like the first image best....  as I see it in post.   Its fine blown up too, for looking for fine details....  but for eye impact IQ (hmm.... .  I rather like that phrase!)....  Number one.  Downscaled as I see it in post on my screen.  The second is fine too....  just a bit over sharpened to my (admittedly conservative) eye.  :)))))

Truly a great image no matter how you look at it!

Mike

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5 hours ago, WestCoastCannuck said:

I like the first image best....  as I see it in post.   Its fine blown up too, for looking for fine details....  but for eye impact IQ (hmm.... .  I rather like that phrase!)....  Number one.  Downscaled as I see it in post on my screen.  The second is fine too....  just a bit over sharpened to my (admittedly conservative) eye.  :)))))

Truly a great image no matter how you look at it!

Mike

Hi Mike Thanks for that. I agree the top image does give you that natural wiggle room that a lot of us seem to want to nail. Infact its your work both in quality and sharpening presentation, that has been making me think a lot about it recently. Understanding your approach and appreciating its strengths. (but also considering any weaknesses) As i said before no one gets something for nothing. Different approaches will have different strengths and weaknesses. It works both ways. No one is right or wrong its personal taste i guess. Me and you are closer on this, than we are far apart i feel. I Wanted to do a 150% resize for the purpose you talk about making it easier for the eye to pick out two close points, with a lot of the smaller hard to see borderline craters. I Just tried drizzle to achieve this resize, as its not something i do a lot. I didnt expect drizzle to be doing anything special to the image. But was fun to experiment with nonetheless. Next time i may just resize as its faster. Or not resize at all. I wanted 150% But SGL turned it into more like 200% a bit over the top to be honest. But as you say resizing does make it easier to pick out fine details. Sometimes worth trying perhaps ? 

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19 hours ago, neil phillips said:

Hi Mike Thanks for that. I agree the top image does give you that natural wiggle room that a lot of us seem to want to nail. Infact its your work both in quality and sharpening presentation, that has been making me think a lot about it recently. Understanding your approach and appreciating its strengths. (but also considering any weaknesses) As i said before no one gets something for nothing. Different approaches will have different strengths and weaknesses. It works both ways. No one is right or wrong its personal taste i guess. Me and you are closer on this, than we are far apart i feel. I Wanted to do a 150% resize for the purpose you talk about making it easier for the eye to pick out two close points, with a lot of the smaller hard to see borderline craters. I Just tried drizzle to achieve this resize, as its not something i do a lot. I didnt expect drizzle to be doing anything special to the image. But was fun to experiment with nonetheless. Next time i may just resize as its faster. Or not resize at all. I wanted 150% But SGL turned it into more like 200% a bit over the top to be honest. But as you say resizing does make it easier to pick out fine details. Sometimes worth trying perhaps ? 

Hey Neil!  Big time thanks on comments about my work.   SO true there is no right and wrong...  and I am thrilled that my way of doing things has had some little impact on your own!  As you say, our tastes in the final look of things are pretty close anyway. 

I hope one day  I may do some closeup work in the same league as yours....  albeit likely in a smaller scale given my range of aperture - and possibly limits of seeing here.  

For myself, this post has really shown the value of drizzle....  maybe.  As you say,  perhaps a resize might achieve a nearly-as-good result.   My own few attempts with drizzle a while ago were somewhat agonizing on the time it took to make the larger file and perhaps due to insufficient quality of data gave a "meh" result.   Maybe worth a try again with really good closeup data from the 290MM - I believe it was the vastly larger 183MM files I tried it on.   First for me though is an easier and faster thing - there is a resizing module in Astra Image I should try out that has potential, it has a few different scaling algorithms to choose from.  I will try that sometime on data that may benefit.   Here, your drizzle copy gave a very smooth and easy on the eyes view that made details easy to study - I think the intended result!

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I used astra image many moons ago. Seem to remember some good deconvolution sharpening routines on there. Always liked experimenting. Drizzle was just a resize option i tried.  As you know Mike its data that counts. Get good data and a lot of experiments will likely work out ok.  Looking foward to seeing your new Frac under good seeing. Got my old EQ 4 mount running. And got lucky finding a RA drive for it from Germany. Frankenhammer is no more

Soon i should at least be able to do some barlow work with both the 114 Newt, and 120 achro Evo. A bigger mount is weeks away. But ordered. Smaller instrument work is a lot of fun. Having a lot of fun using smaller scopes lately. Very satisfying ive found. Its all art to me. The level has become more irrelevant as the years have gone by. Loving my astronomy again. Thats the most important thing for anyone. Not scope size

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