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Mr trick

Best setup for moon detail

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10 minutes ago, ronin said:

The moon falls into an odd catagory, I recall helping someone with a 200mm lens on a camera get some shots. The moon is big enough and bright enough that is the camera is set to center spot metering then you can point a camera at it in auto mode and get an image. There is not really anthing else that we can do that with.

From memory most seem to go down the planetary imaging approach and use an SCT/Mak and a webcam. Then enter the video into software, select the best frame and stack say the best 100 or so that match it.

Do you want to get all the moon or a specific crater, would expect taht a refractor, say Tal or 102/1000mm ES/Bresser etc would get a good single shot of the whole moon. For a single bit say the crater Archemedes, then a Mak/SCT is required (likely with barlow).

Will ask Why the moon?

Reason is that when people say they want to image planets I tend to point out the limited number of planets to image (3). How many images of the moon do you want?

If the intention is to build up a record of the various lunar craters as a sort of reference then no problems.

 

Thanks for replying 

 I'm just extremely interested and enjoying learning a new topic. I'm amazed by the skill set of everyone on here and taken back by the help I'm getting. 

I have heard things said about our moon that it's easier to pretend it's not there than explain it?       This is enough to start my mind asking all sorts of questions. 

  If we could read newspaper print  or read a numberplate from 35k miles out in orbit !  Looking back through the same atmosphere that hinders all ground based astronomy.  Why can't nasa or other agencies with satellites, telescope's and even  Luna orbiter's see closer in ,on Apollo landing site with only unpolluted, clear space  ??

 

 

 

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2 minutes ago, michaelmorris said:

Resolution limits was explained to me this way.

All optics have an edge - this is usually the outer edge of a refractor or mirror.  Waveforms (such as light) diffract when they hit an edge.  These diffraction patterns of light propagate across the whole field of view, reducing the amount of fine detail that is visible.  The larger the aperture of the telescope, the lower the ratio of edge (circumference of the optics) to the area of glass (the undistorted light).   Thus the larger the aperture of the optics, the less the relative effect of diffraction on image quality, leading to higher resolution.

I've read the scientific explanation of it, bit like dropping a pebble in a puddle but it's a bit hard to get my brain around :grin:

Dave

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Speaking of being able to image the Moon and Planets with the same scope, here's one from a while ago single frame using DSLR and 10"SCT.

Moon and Uranus

Dave

Moon-&-Uranus-enlarged.jpg

 

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1 minute ago, Davey-T said:

Speaking of being able to image the Moon and Planets with the same scope, here's one from a while ago single frame using DSLR and 10"SCT.

Moon and Uranus

Dave

Moon-&-Uranus-enlarged.jpg

 

Awesome! Just wow.

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15 minutes ago, Mr trick said:

Thanks for replying 

 I'm just extremely interested and enjoying learning a new topic. I'm amazed by the skill set of everyone on here and taken back by the help I'm getting. 

I have heard things said about our moon that it's easier to pretend it's not there than explain it?       This is enough to start my mind asking all sorts of questions. 

  If we could read newspaper print  or read a numberplate from 35k miles out in orbit !  Looking back through the same atmosphere that hinders all ground based astronomy.  Why can't nasa or other agencies with satellites, telescope's and even  Luna orbiter's see closer in ,on Apollo landing site with only unpolluted, clear space  ??

 

 

 

Ok, after doing a bit of research, it seems that spy satellites have a resolution of between 4 and 10 cms, so no, they cannot read newspapers (though i'm sure we'll never know the true specs), and they fly at between 200 & 400 miles above the earth (35k km is where the communication satellites live, my bad).

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27 minutes ago, Davey-T said:

A spy satellite is a completely different kettle of fish to the sort of camera that can be sent to the Moon from the perspective of weight alone.

People can't understand why we couldn't fly to the Moon in the Space Shuttle despite what Sci Fi movies would have us believe.

Dave

To be totally honest , I don't understand how people fly in a vacuum at all . If there is no atmosphere , what does the jet engine push off?

 

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1 minute ago, Mr trick said:

To be totally honest , I don't understand how people fly in a vacuum at all . If there is no atmosphere , what does the jet engine push off?

 

Itself, every action produces an opposite and equal reaction.

Dave

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Mr Trick - I think it pushes off the rocket itself doesn't it - every action having an equal and opposite reaction - hence the rocket then moves away from it - all that sort of stuff - Mind you I was never big into physics LOL

 

Edit:

 

Dave - almost dual posting - great minds and all that jazz!

Edited by JOC
Dave - great minds and all that jazz!
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2 minutes ago, Mr trick said:

To be totally honest , I don't understand how people fly in a vacuum at all . If there is no atmosphere , what does the jet engine push off?

 

Its all down to Newtons Laws of Motion.

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Ok IV been googling, no more physics questions from me haha

Think I need to enroll on a course. Wish I'd gone to a better school haha

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1 hour ago, Mr trick said:

I haven't bought any equipment yet.  Purchased so far books , magazine's and a planisphere.   I have a small pair of binoculars for now.

 Definitely need to learn alot before any nice shiny toys are aquired.  Was looking at a mak127 but much more research is required

The Mak 127 is a very nice scope for visual observation of the moon and planets. :thumbsup:

Mike

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I used to enjoy viewing the moon in binoviewers using an 8" sct (I now use a 9.25" sct). It really is an enjoyable 3D effect that makes you feel like you're flying a couple of hundred miles above the surface - and the detail is amazing. A large Mak would do it too. But not the kinda jumbo jet detail you're suggesting. It would be a good idea to get down to your local astro club and see the sorta views you get from different scopes to help you decide. :)

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54 minutes ago, Mr trick said:

To be totally honest , I don't understand how people fly in a vacuum at all . If there is no atmosphere , what does the jet engine push off?

Once something has reached the escape velocity of the body it is trying to escape it can inevitably remain in orbit, fall back into or continue escaping the gravity well of the body depending on trajectory and maintained speed.  The engines only need to push against the atmosphere for the beginning of the journey, once the speed and trajectory are established, the nearer vacuum environment allows the craft to be met with a much lower resistance.  Most of the fuel is used early on and the tanks are dumped reducing mass of the craft.  Smaller thrusters are then used in small spurts to make tiny adjustments to allow manoeuvre 'steering', & 'braking' which can allow a controlled re-entry back into the gravity well of the Earth.

I often remind myself of the following :

If you hold a loaded gun 100cm above the ground and at the same time hold a bullet in your hand 100cm above the ground and fire the gun and let the bullet go at the same time they both hit the ground at the same time.  If Usain Bolt was to do a sprint and a jump on the small moon of Mars he could quite easily exceed 11.39 Metres / second and would would be lucky to land again (as he exceeded the Phobos's escape velocity).  Here on earth he would have to sprint at 11,186 KM / second to achieve the same thing.  

Edited by jabeoo1

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1 hour ago, Mr trick said:

To be totally honest , I don't understand how people fly in a vacuum at all . If there is no atmosphere , what does the jet engine push off?

 

I found this explanation on the web, seems useful to answer your question:

https://www.quora.com/How-do-rockets-accelerate-in-space-or-vacuum-in-absence-of-any-material-to-provide-them-the-required-reaction-force

Inside a rocket, there is a combustion chamber in which we ignite a fuel and oxidizer.  They burn, converting into a very hot gas that wants to expand, rapidly.  But the chamber is rigid and there is only one small hole, so the gas is ejected through that hole, out of the back of the rocket.

Newton's third law tells us that,

For every action there is an equal and opposite reaction.

Imagine you are on roller skates and you are holding a heavy cannon ball.  What happens if you throw the cannon ball in front of you?

If there is a force propelling the cannon ball forwards, there must be an equal and opposite force propelling you backwards.

But, you won't move backwards as quickly as the cannon ball is moving forwards, because you are more massive.  This concept involves momentum.

Momentum (P) equals the mass of an object (m) times its velocity (v).

Momentum of a system is conserved.  That means that without outside influence, the total momentum of a system is constant.  So, if you throw the cannonball and change its momentum by giving it a velocity in a particular direction, your change in momentum will be equal and opposite.

Tsiolkovsky came up with a rocket equation based on all of this:

The change in speed of a rocket is equal to the exhaust velocity of the fuel times the natural log of the initial mass of the rocket divided by the final mass.  The final mass is the initial mass minus the fuel that was ejected out of the rear of the rocket.

So, we can make a rocket go faster by either increasing the exhaust velocity (make the exploding fuel hotter) or by ejecting the fuel out of the back of the rocket faster.

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Mr trick, you wonder why spy satellites see details centimeters across on the Earth, but we can't see details smaller than hundreds of meters across on the Moon?

Spy satellites orbit a few hundred kilometers above the Earth, say a spy sat orbits about 400 kilometers above us. The Moon is about 400,000 kilometers away, 1,000 times more distant, thus it is 1.000 times more difficult to see features on the Moon.

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Spy satellite imagery doesn't actually have the high resolution that many people believe. Tales of being able to read number-plates or newspaper headlines from a satellite were encouraged as mis-information. One of the best stories is that a Cold War CIA director used satellite imagery to find the golf-balls he lost on his local course - pure myth!

The National Reconnaissance Office in the USA had a 9 level scale to define the resolution of satellite imagery during the Cold War. The in-house publicity for the most detailed level 9 clearly showed an East German border guard taking a leak in the snow! Unfortunately the photograph was taken from a low flying aircraft and not a satellite.

As an aside, the early spy US satellite cameras used photographic film which had to be ejected back to Earth and recovered - an incredibly complex process! If you're interested, check out  https://en.wikipedia.org/wiki/Corona_(satellite)

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I work professionally with remote sensing images, and the best I have worked with had a 30cm/pixel scale, but 50cm/pixel or 1m/pixel is far more common. I have worked with 15cm/pixel images but these were aerial reconnaissance images. Some spy satellites (Keyhole) are essentially like Hubble space telescopes pointing downward, and have a theoretical resolution of 5cm on the ground (from an altitude of 250km). These satellites can maneuver to lower orbits, and gain altitude later, I gather.

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The general public, when shown the Moon through our telescopes often ask if we can see any evidence of mankind's activity on it. We explain that the highest magnification we could ever employ would be 1000X and as the Moon averages 240,000 miles distant you would then be looking at it as seen by the naked eye from 240miles so no hope of seeing footprints or flags.   :icon_biggrin:

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4 minutes ago, michael.h.f.wilkinson said:

Some of my best lunar shots to date are these two

Moon_201334_g3_ap4045LR400.jpgMoon_202200_g3_ap5980LR400.jpg

(click for access to full resolution)

One pixel is roughly 400 m. This was shot with my 8" SCT

This is pretty much exactly how i see the Moon with my 8" SCT (and high mag EP of about 6-8mm). The 1st time i observed the Moon with my 8" SCT is something i will never forget. I felt like i was orbiting it in a lander.

Edited by LukeSkywatcher
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Just now, LukeSkywatcher said:

This is pretty much exactly how i see the Moon with my 8" SCT. The 1st time i observed the Moon with my 8" SCT is something i will never forget. I felt like i was orbiting it in a lander.

It is even better with ulta-wide angle EPs. My first UWA was the Meade 14mm Series 5000 (Mk-I), and the view blew me away. To see the whole moon at 145x magnification is indeed like looking through the porthole of Apollo when it was about 2650km (1650 miles) from the lunar surface. Awe inspiring

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4 minutes ago, LukeSkywatcher said:

This is pretty much exactly how i see the Moon with my 8" SCT (and high mag EP of about 6-8mm). The 1st time i observed the Moon with my 8" SCT is something i will never forget. I felt like i was orbiting it in a lander.

Wow, now there is a feeling I would like to have myself someday!

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8 hours ago, Davey-T said:

People can't understand why we couldn't fly to the Moon in the Space Shuttle despite what Sci Fi movies would have us believe.

Well surely the space shuttle required an atmosphere as thick as the earths to land didn't she?  She glided like an aeroplane on those big wings of hers didn't she and got lift because of the passage of air over her wings.  Therefore she couldn't have landed on the moon, besides which there was no runway either and no rocket boosters to help her get back in the air again!!   LOL

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I'm using an Ethos 4.7mm on the Moon at the moment with my 4" Tak - the whole lunar disk with a little room to spare at the edges at 191x ! B)

Al Nagler worked on the LEM simulator optics and the Ethos SX eyepieces are apparently designed to provide a similar experience.

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Nice one John, the moon does look lovely tonight. I recall doing something similar when I had my TV85 and a 3.7mm Ethos; gave x162 I think, an amazing view so yours must be something incredible!

No scoping for me but a quick look around with the binos later I hope.

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