The Official Shoot the Moon Thread

Is the moon flat or round[Sphere]? so all the talk about the earth flatteness, so what about the moon? The image is proving that it isn't flat at all, many said it is fake and photoshop, GREAT

Tareq wrote in post #18637486
Is the moon flat or round[Sphere]? so all the talk about the earth flatteness, so what about the moon? The image is proving that it isn't flat at all, many said it is fake and photoshop, GREAT

Did you shoot through a telescope? The FL looks like half a mile

itsallart wrote in post #18637503
Did you shoot through a telescope? The FL looks like half a mile

Yes, a telescope

itsallart wrote in post #18637503
Did you shoot through a telescope? The FL looks like half a mile

FL ? ? ?

Inspeqtor wrote in post #18637524
FL ? ? ?

FL=Focal Length. In other words, it was looong. Maybe.

Ballen Photo wrote in post #18637528

Inspeqtor wrote in post #18637524
FL ? ? ?

FL=Focal Length. In other words, it was looong. Maybe.

Thank you

I shudda known that. I need a list of all the abbreviations for photography that I can have on my desk or somewhere I can find it.....

Tareq wrote in post #18637486
Is the moon flat or round[Sphere]? so all the talk about the earth flatteness, so what about the moon? The image is proving that it isn't flat at all, many said it is fake and photoshop, GREAT

No, neither are flat. But the Moon is totally hollow with Reptilians, millions of them, living deep inside. One must wear aluminum foil pyramids or our souls could be stolen. I saw a YouTube video about this a year ago, so it must be true. Oh, great picture!

Inspeqtor wrote in post #18637524
FL ? ? ?

2700mm

Ballen Photo wrote in post #18637528
FL=Focal Length. In other words, it was looong. Maybe.

And i thought that 2700mm isn't long enough, good i didn't try to go longer, one day if you want i can give it a try, maybe 5000mm, or 5400mm, i can do also 8100mm but then the sharpness and details will be low, i don't know if that is really long or not

You can tell this is a terrestrial photography forum primarily, as everyone wants to know focal lengths, when it's aperture that matters for resolving detail, and asking what the pixel size and focal-ratio sampling pairing was.

For example, image the moon at a focal length of 2500mm with a 10 inch (250mm) aperture compared to a focal length of 2500mm with a 5 inch (127mm) aperture, and while the FOV will be the same with the same sensor, the detail resolved regardless of focal length will be different. Even a full lunar disc will look significantly different, with more fine detail, craterlets, small features, defined well, rather than a blurry smudge or completely non-existent visually, from smaller aperture instruments (such as a camera lens). This is assuming pixel size and sampling focal-ratio are matched fairly well.

And when you really start to play with long focal lengths, you run into the real limit of it all, the seeing.

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Example, here's what a 150mm aperture resolves:

IMAGE LINK: https://flic.kr/p/M5xm​ga

IMAGE LINK: https://flic.kr/p/26kw​NVQ

MalVeauX wrote in post #18637689
You can tell this is a terrestrial photography forum primarily, as everyone wants to know focal lengths, when it's aperture that matters for resolving detail, and asking what the pixel size and focal-ratio sampling pairing was.

For example, image the moon at a focal length of 2500mm with a 10 inch (250mm) aperture compared to a focal length of 2500mm with a 5 inch (127mm) aperture, and while the FOV will be the same with the same sensor, the detail resolved regardless of focal length will be different. Even a full lunar disc will look significantly different, with more fine detail, craterlets, small features, defined well, rather than a blurry smudge or completely non-existent visually, from smaller aperture instruments (such as a camera lens). This is assuming pixel size and sampling focal-ratio are matched fairly well.

And when you really start to play with long focal lengths, you run into the real limit of it all, the seeing.

+++++++++++++++

Example, here's what a 150mm aperture resolves:

IMAGE LINK: https://flic.kr/p/M5xm​ga 22_51_30_g4_ap200_stac​k by Martin Wise, on Flickr

And here's what a 250mm aperture resolves:

IMAGE LINK: https://flic.kr/p/26kw​NVQ Craters03 by Martin Wise, on Flickr

Very best,

All good, but i really try not to think about that too much, i have good scope but i know if i keep thinking about its limitations then i will go and waste $$$$$ for more and longer/better scopes only to get details, so i just pass that and keep shooting with whatever i have, i don't want to jump into very expensive tools yet, i am thinking about 14" SCT really, and many trying with me to avoid it, first weight and second is seeing, so if seeing isn't good at all then i heard somewhere that even 14" won't resolve more than just 8" scope, so why bother for longer higher aperture if it won't help while seeing isn't helping?!!!

I am happy so far with my 2700mm scope for now, i am practicing with it, with processing i can get some nice details, but for planets i am still struggling, but i won't give up, for the moon i think any scope or lens can do just fine either full disk or closeups, i remember long time ago in this site that someone was using Sigma monster lens i think 800mm or sigzilla not sure with many extenders to show the moon at finest details, i tried my 300mm with 2 extenders and couldn't get even closer, but now with a scope and processing i just now got details needed for the moon, and this will help me when i will shoot with lenses too, the camera i use is also helping, i mean once i started astrophotography my knowledge just growing, i try not post much in this site, but as long i focused on AP now so maybe this is what i only have to post, if i won't post shots of the moon or sky targets because they are not terrestrial or i used a scope then i won't post anything here.

Also with your examples above, i don't know about the full gear details, but are you comparing a scope with Barlow to a native focal length? unless that scope with Barlow are highest quality then yes, but my scope of 2700mm is cheaper in price than 8" SCT which has 2032mm focal length but it is not that much details than 8" anyway, and i saw amazing results from 8" with Barlow than my 7" scope of 2700mm native, but that won't help much if we just look at 2 same view of a target with different scopes and then we saw one with higher or finer details, for that the best planets shots i've seen where from 16" and 14" SCT, and this will come with a big price too, i do have 8" Newtonian as well that i never used yet, it has 1000mm focal length, i do have 3X Barlow, i would like to use it with this Barlow and compare it to my other scope native 2700mm and see the difference too.

MalVeauX wrote in post #18637689
You can tell this is a terrestrial photography forum primarily, as everyone wants to know focal lengths, when it's aperture that matters for resolving detail, and asking what the pixel size and focal-ratio sampling pairing was.

For example, image the moon at a focal length of 2500mm with a 10 inch (250mm) aperture compared to a focal length of 2500mm with a 5 inch (127mm) aperture, and while the FOV will be the same with the same sensor, the detail resolved regardless of focal length will be different. Even a full lunar disc will look significantly different, with more fine detail, craterlets, small features, defined well, rather than a blurry smudge or completely non-existent visually, from smaller aperture instruments (such as a camera lens). This is assuming pixel size and sampling focal-ratio are matched fairly well.

First, very good shots of the Moon, but aren't you stuck with whatever fixed aperture that comes with a scope? I would imagine that a scope with a large aperture as you describe would be quite spendy?

Ballen Photo wrote in post #18638023
but aren't you stuck with whatever fixed aperture that comes with a scope? I would imagine that a scope with a large aperture as you describe would be quite spendy?

Every lens, scope, etc, has a fixed aperture. It's the entry into the objective. After that, you can mask down aperture at different points, be it up front, or farther down the light cone (such as with a closing blade system found in camera lenses). The fixed aperture doesn't matter, the point is simply that selecting an instrument with large aperture for the purpose of high resolution imaging is. The point is that aperture is what is determining the potential resolution here, not the focal length. Focal length always comes up, but it's not important. This gets overlooked because, well frankly this is a photography forum mostly dedicated to terrestrial photography where the concept of aperture is a misnomer and often used to simply say "focal-ratio" and even the cameras use the word aperture to really say focal-ratio. But really, aperture is the physical opening to the objective, and it's the limit for potential resolution. You can have a 2,000mm focal length (found often in this thread with combination of TC's and 500~600mm lenses), but the resolution isn't going to be anymore than what the aperture allows (say, 95mm opening into that lens for example which is very common). That small opening into the lens, that limited aperture, is why you cannot resolve more detail, regardless of pushing the focal length to be very long to have a higher magnification.

As for being spendy, well, this thread is full of 5D/Nikon/Sony A, etc, cameras with 400mm, 500~600mm lenses, etc, taking pot shots at the moon with $2k~5k instruments left and right in here. It's quite common to see a 6D, 5D, and a 100-400 or 150-600 or equivalent in this thread, costing $2k easily, and more. Granted, no one gets those cameras and camera lenses for high resolution lunar photography, I know that. Yet, a 150mm aperture telescope is as little as $199 brand new and will stomp out any lens presented in this board for the purpose of high resolution lunar photography as it will simply resolve more. And a 10 inch (250mm) aperture telescope is as little as $599 brand new. That's a huge telescope. Notice I'm not referring to their focal-lengths nor focal-ratios, as it doesn't matter, only the aperture as that is where the resolution potential comes from. They don't cost much. The spendy side of things is the tracking mount that carries the 40lb monster. Yet, still can be had for less than what a lot of camera+lens combos are in this board. But again, this is a terrestrial photography forum, not dedicated to astrophotography, so I wouldn't really expect it. You can image astrophotography with very inexpensive efficient USB CMOS cameras as it's done with video, not still photography, for high resolution imaging.

For high resolution lunar/solar/planetary astrophotography a few things can be summarized to make it simple:

Aperture (the physical diameter of the opening into the objective): resolution and brightness
Focal-length: magnification and scale
Focal-ratio (F-stop, and often misnomer "aperture"): scale and sampling
The seeing is the great limit to everything through (air turbulence), you cannot push magnification/scale higher if the seeing is poor, it's the ultimately limit from terrestrial Earth for this purpose.

To combat poor seeing, and image at a large scale, it's very common to use monochrome sensors and restrict the wavelength of light we image to be somewhat more narrowband as some wavelengths are less prone to the turbulence blur, such as infrared. It's common to use a red long pass filter and image in red light passing 610nm and longer infrared, and block all the blue & green light which is more prone to blur in the air turbulence on a monochrome sensor.

To get the best resolution you can out of the imaging system for this purpose, the larger the aperture, the more potential resolution can be resolved. The longer the focal length, regardless of the aperture size, the more magnification and the larger the scale will be for imaging purposes. The combined ratio, or focal ratio, determines that scale and this is what you base sampling on, which is matching pixel size to focal-ratio sampling so that you're not over nor under sampling, and retaining the highest resolution you can at the pixel level.

So for example, someone imaging with a 250mm aperture instrument with a 2500mm focal length and a camera with 5.86um pixel size, if you multiple the pixel size x 5, to get close to the optimal sampling point for the pixel size, you would use that number to figure out what focal-ratio you need to image at, as this is the scale and sampling. So 5.86um x 5 = F29.3. So for that pixel size on that particular sensor, it is ideal to image at F29 (or F30 realistically) for optimal sampling so that the resolution is captured at the pixel level (you cannot get more detail/resolution after this point, and if you push the scale up, you are oversampling and you do not gain more detail/resolution). So if my instrument is F10, I need it to be F30. You can either mask the aperture smaller to produce that focal-ratio, or you can increase focal-length to produce that focal-ratio. But this is how imaging these objects is approached. The focal-length is not something that is focused on. Sampling, scale and aperture are.

Hope that helps.

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Another example showing the difference in resolving power between aperture sizes, if the above information is incorporated for sampling:

150mm (6 inch) aperture resolution:

IMAGE LINK: https://flic.kr/p/NSEg​6v

IMAGE LINK: https://flic.kr/p/GRCz​H2

MalVeauX wrote in post #18638206
Every lens, scope, etc, has a fixed aperture.
<----Snipped so you folk don't have to read duplication. ---->
Hope that helps.

I'd say that helps a lot. Your definition helps with understanding quite a bit.
Another question, do you prefer a cat scope, or a traditional?