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More testing


neil phillips
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After discussion with Astrolulu. And some rather nice images from him. Trying to push my captures a bit more to see if i can find that magical balance between detail and naturalness. 

With good data I don't think i am that far off. Captured under reasonable seeing with my 245mm Newtonian at F12.6 zwo 178mm 500 frames, from 6000 captured. I think i am as close as can be got to that mystical detail versus natural balance at this size scope in the UK others may not agree. Beauty is in the eye of the beholder. downsized to 75% from capture size for quality enhancement. Best viewed at full size I can remove the ringing but often prefer to leave it as is. I can't see any typical noise. in the first. And struggling to in the second. 

Two renditions the last slightly sharper for comparison. Out of interest I think my preference is the slightly less detailed, (but better balanced) top capture

c1.png

c1.png d.png

 

Edited by neil phillips
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As you said yourself - the assessment depends largely on the recipient. I still prefer the more sharpened one, but both are great and if you didn't compare them next to each other, no one would probably think of accusing them of too much or too weak sharpening. Note, however, that this natural effect is due to the presence of some noise. It is delicate - but it is present.

For example, the floor of the Longomontanus crater. If there was no noise and the floor was perfectly smooth, you would probably get the feeling that the photo is artificial and oversized - which is the effect I mentioned when we discussed my photo where I tried to remove some noise. So a bit of noise is in my opinion not only acceptable, but desirable if we want to maintain a relatively large scale of the photo.

I must admit that I experimented several times with the deliberate addition of noise to avoid the impression of artificiality and too aggressive filtering. 🙂

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This is where if there is noise i think it would be showing up the most. It wouldn't surprise me if there is a touch of noise. As I don't normally sharpen this heavy generally. so, pushing the sharpening will no doubt. Make it more likely. This is what I was saying to you about being unsure of what is noise and what is not. On your images it took me a while to figure out how much noise was in some areas because the level of fine detail was so good. and the noise so fine it did tend to blend in. But i could feel it generally. Perhaps that's true here too. But with likely less sharpening and a frame count of 500 frames. There is likely less noise. I Just took the 75% reduced captures and resized up to 150% to make it easier to see closer. I could be wrong but i think most of those inflections on the floor are real detail. I think the brightening on the leading edge of those inflections on mostly the sharper image could be interpreted as a form of noise I suppose. The black areas will tend to highlight some noise agree on that.

But finding it hard to see any noise in those blow ups to be honest. But as I said I could be wrong.

We have seen eye to eye mostly on a lot of these discussions. Not sure I agree with the premise a bit of noise is desirable at larger scale? Sounds like a get of jail free card. The idea should be to get detail without noise. Of course, i agree there is always going to be some noise, in images. including these here for sure. But I can't really see it very well if at all. That wasn't the case when I highlighted two blow ups on your page, it was easy to see in certain areas. (There were other areas i didn't highlight) it was moving around in different places randomly? Which in my opinion is very far from ideal?  A good example of not having to tolerate noise, (well not much anyway) either with careful sharpening or larger optics and levels control and or larger stacks, is Christain viladrich. 

Platon-28octo2021-3h04UT-RC500-ASI1600-red.jpg (2856×2864) (astrosurf.com)

Again, there is still likely noise agreed. But he does have it firmly under control. what noise is left on the floor of Plato here as an example, is most likely jpg noise. Though without seeing the tiffs of course I can't be absolutely certain. Regardless even as jpegs at the size presented its hard to see. 

Hard to see will always be my ideal

I realize the scope is massive. But smaller scopes can produce images where noise isn't moving around randomly? Why your images are so good, is because the detail is so good it's easier to tolerate the noise. Because the detail is stronger. I agree there.

 we may have to agree to disagree on the premise some noise is desirable. Detail is desirable. noise is a distraction in my opinion.

Again, there most likely is noise on my images posted here. But even with blowing up to 150%. from a 75 % reduction ( not ideal as i should have resampled from full size) I am not finding it easy to see the noise?  We can't always agree on everything and that's fine. it makes life interesting. Your images are amazing and really got my attention. I just contend they could be better if you dropped the notion some noise is desirable. and found a good way to achieve that without losing the detail. A limited number of frames isn't going to help you. But of course, that might be better to me. And not you. And it's what you think about your own images is the most important thing for you. If you're happy. No one has the right to tell you shouldn't be. I will certainly not do that. I speak for me. That your presenting on a open forum. We are all friends here we can disagree on certain things and still have total respect. I really admire what your doing. I am so glad you showed the forum your images. you make me realize

I need to still perfect what i am trying to do. I hoped my influence on you would be the same. But thats for you to decide. 

crop.png 150.png

sharper crop.png

Edited by neil phillips
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1 hour ago, Kon said:

First two stunning.  Last two, not your usual natural appearance; they seem quite noisy with quite a bit of artefact.

LOL that blows my premise. it was a blow up of the same two shots kon. Personally i can not see any noise perhaps my glasses need cleaning 

I can see lots in the black areas.( thats normal for me )  but struggling elsewhere

Edited by neil phillips
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47 minutes ago, astrolulu said:

I meant this:

noise.jpg

Hidden noise is rather a different question if you have to drastically alter the image to see it. Also, by changing the levels that drastically. You're highly likely creating extra noise in the process.. ?

Moving the goal posts a little there. I didn't have to do similar on your image. it was already there. I could see it as is, even at 100%

Not sure that's the case here. My image doesn't look like this in the slightest. If you have to change the levels that drastically to see it. I think i am doing well

especially as i used a lot more sharpening than i normally do and its still well controlled 

 

Edited by neil phillips
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Wondering what you did to make it look that bad lol. Just severely dropped the blacks here.  Which often will reveal noise easily. And still it looks good ???

crop.png 150.png b.png

sharper crop.png b.png

 

 The sharpest crop Here i dropped the blacks and increased the whites into bad clipping. And it still  looks good quite happy with that actually

sharper crop.png

Edited by neil phillips
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Anyway, i am fairly certain there isn't a ton of noise there. Even though i increased my sharpening a lot over what i normally do. Not in the same league as what i pointed out to you without enhancements?  From there i think the discussion is getting non conductive to either of us making improvements. I will keep an eye out on your work as it is stunningly good. If you prefer not to take my comments on board i am fine with it. 

Cheers

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Neil, there's no reason to argue. As I have emphasized several times, the presence of noise is nothing wrong in my opinion. On the contrary - I believe that the presence of a certain level of noise is necessary so that the photo at this magnification scale does not take on an artificial, "plastic" expression. You have just as much noise as needed - I'm sure that without it, the effect would be much worse.

And the noise *is* there, you can see that I only raised what already was there - I did not create anything new in this process. Both dark and light, smooth parts of your photo are covered with the same artificial pattern caused by the noise. This must be the case, unless you are using the noise removing filters.

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16 minutes ago, astrolulu said:

Neil, there's no reason to argue. As I have emphasized several times, the presence of noise is nothing wrong in my opinion. On the contrary - I believe that the presence of a certain level of noise is necessary so that the photo at this magnification scale does not take on an artificial, "plastic" expression. You have just as much noise as needed - I'm sure that without it, the effect would be much worse.

And the noise *is* there, you can see that I only raised what already was there - I did not create anything new in this process. Both dark and light, smooth parts of your photo are covered with the same artificial pattern caused by the noise. This must be the case, unless you are using the noise removing filters.

Not arguing. Just may not agree.  And that's fine. As I said I agree i could be wrong. Your adjustments are taking on noise that my alterations did not. So that's odd. Most of those patterns and inflections look like tiny craters and reflections to me. Even when i tried to make them look bad with my examples. Other than sharpening the image. Which would be getting silly to prove a point. 

Not sure how to progress with the discussion. We can disagree and still be friends astrolulu. No bad feeling in the slightest. Lets just chalk it up as different opinions. 

Edited by neil phillips
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7 hours ago, neil phillips said:

LOL that blows my premise. it was a blow up of the same two shots kon. Personally i can not see any noise perhaps my glasses need cleaning 

I can see lots in the black areas.( thats normal for me )  but struggling elsewhere

I saw the same in your image as @astrolulupointed, but as you posted it. It's mostly in the main plateau and some of the greyish areas outside. As you say it could be small cratelets or shadows.

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7 hours ago, neil phillips said:

 Most of those patterns and inflections look like tiny craters and reflections to me.

You summed up very well the most important noise function I mentioned when we discussed my photo. It is needed precisely to introduce this type of uncertainty as to the appearance of the surface where, due to the scale, we still expect to see details, but where the resolution does not allow it anymore. Thanks to the noise, you can wonder if it is not due to the presence of some small craters, for example - and without it you would see an ideally smooth surface, which at this scale of the photo would be simply untrue and it would appear artificially.

This noise is obviously artificial and does not represent any detail. We see the same uniform, stohastic pattern on every bit of the smooth surface of this photo - exactly the same one that shows in the shadows, where no real fine detail is available for the camera. But the very fact that we are discussing it shows that the noise has done its job, has raised doubts - and that is its role and advantage.

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Again we differ where i believe some fine detail is possible in the shadows, in fact i have seen it many times in situations where it is obviously craters on the fringe of visibility. Because of the size and shape shows it as such. I will agree it is hard to tell the noise from detail. So there may well be more noise in the image than i assumed. But how much is anyone's guess ? 

I still think most of what my eye is catching is detail. If i am wrong. We can only be true to ourselves. And not what others want us to be. From that. its been a good discussion. let's leave it at that.

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