I have come across this notion, in different forms about
"The larger the
I don't understand the logic because it seems to insinuate that small
The part that with larger
So what does the experts say? folklore or fact?
Piet Le Roux wrote: ↑Wed Sep 30, 2020 8:03 pm "It is a scientific fact (not folklore) that large aperture scopes are more affected by seeing conditions." : this statement involves long exposures and the magnitude by which its affecting a large aperture telescope...not really what I am interested in.
Well, you're wrong. Factually scientifically wrong and you are pushing folklore against scientific facts.I am specifically referring to visual observations and the question, for me, is if a small aperture telescope could ever outperform a large aperture telescope, by showing more detail, of a object during bad seeing conditions, because this is what some people are deducting from these rather complex statements that are being presented by some academics.
The KISS answer to my question, for me, is still....no!
This is false. If the seeing is producing a 2" disk then resolution is limited to 2" by the atmosphere.turboscrew wrote: ↑Wed Sep 30, 2020 8:38 pm "The larger the aperture, the larger the volume of air that the light rays coming into the scope must pass through. Thus scopes of larger aperture tend to be more sensitive to turbulent air ("seeing") than scopes of smaller aperture."
I'm not sure but...
I don't think the scope can be affected by seeing.
I think it's about the quality of image - whether drawn on film or retina.
It's just that better quality image doesn't necessarily mean more detailed image. It could also mean less detailed image that doesn't jump around.
The physics of turbulence and its effects on optical performance doesn't care whether it is day or night.Solsearcher wrote: ↑Wed Sep 30, 2020 9:55 pm My own personal experiences can easily back up the claim that a smaller aperture can bring better results in not so good conditions .
My main interest in astronomy is solar imaging , I have 3 Ha solar scopes , 60mm 90mm and 150mm . My 60mm scope is very forgiving and can give good results even in poor conditions , My 90mm is less forgiving in poor conditions but works very good in my average conditions . Now by comparison my 150 mm scope requires almost pristine conditions for me to use at all and I am lucky if I see these conditions more than a couple of times a year . The larger aperture not only resolves all of the fine detail I want to capture it also does a very good job of resolving the distortion between my scope and the target. I know this is not night time viewing but I do believe this one example of how a larger aperture can work against you .
As far as it goes, it’s correct but it is still incomplete. It never addresses the effect ofPiet Le Roux wrote: ↑Thu Oct 01, 2020 11:59 am
.......
This fact has led to another piece of folklore: that when the atmospheric seeing is bad, a large telescope shows less detail than a small one. Therefore, supposedly, you can improve the view in poor seeing by stopping down a large aperture with a cardboard mask.
Technically there is a bit of truth in this, but in practice the improvement is nonexistent.
........
The whole article : https://skyandtelescope.org/astronomy-e ... he-seeing/
What's false in that? I don't think the scope itself changes in any way depending on seeing.notFritzArgelander wrote: ↑Wed Sep 30, 2020 9:15 pmThis is false. If the seeing is producing a 2" disk then resolution is limited to 2" by the atmosphere.turboscrew wrote: ↑Wed Sep 30, 2020 8:38 pm "The larger the aperture, the larger the volume of air that the light rays coming into the scope must pass through. Thus scopes of larger aperture tend to be more sensitive to turbulent air ("seeing") than scopes of smaller aperture."
I'm not sure but...
I don't think the scope can be affected by seeing.
I think it's about the quality of image - whether drawn on film or retina.
It's just that better quality image doesn't necessarily mean more detailed image. It could also mean less detailed image that doesn't jump around.
https://weather.gc.ca/astro/seeing_e.html
https://en.wikipedia.org/wiki/Astronomical_seeing
The atmosphere is part of the optical system. It’s a mistake to neglect that. Indeed when you include the atmosphere details and resolution are affected.turboscrew wrote: ↑Thu Oct 01, 2020 2:31 pmWhat's false in that? I don't think the scope itself changes in any way depending on seeing.notFritzArgelander wrote: ↑Wed Sep 30, 2020 9:15 pmThis is false. If the seeing is producing a 2" disk then resolution is limited to 2" by the atmosphere.turboscrew wrote: ↑Wed Sep 30, 2020 8:38 pm "The larger the aperture, the larger the volume of air that the light rays coming into the scope must pass through. Thus scopes of larger aperture tend to be more sensitive to turbulent air ("seeing") than scopes of smaller aperture."
I'm not sure but...
I don't think the scope can be affected by seeing.
I think it's about the quality of image - whether drawn on film or retina.
It's just that better quality image doesn't necessarily mean more detailed image. It could also mean less detailed image that doesn't jump around.
https://weather.gc.ca/astro/seeing_e.html
https://en.wikipedia.org/wiki/Astronomical_seeing
Or is it about image quality being all about details and resolution?
Yes, but in the text: "thus scopes ... tend to be more sensitive to turbulent air". (That's why the emoticon,)notFritzArgelander wrote: ↑Thu Oct 01, 2020 2:52 pmThe atmosphere is part of the optical system. It’s a mistake to neglect that. Indeed when you include the atmosphere details and resolution are affected.turboscrew wrote: ↑Thu Oct 01, 2020 2:31 pmWhat's false in that? I don't think the scope itself changes in any way depending on seeing.notFritzArgelander wrote: ↑Wed Sep 30, 2020 9:15 pm
This is false. If the seeing is producing a 2" disk then resolution is limited to 2" by the atmosphere.
https://weather.gc.ca/astro/seeing_e.html
https://en.wikipedia.org/wiki/Astronomical_seeing
Or is it about image quality being all about details and resolution?
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