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"A good shot" 20th C Ireland. (Read 2909 times)
Sarosh
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Re: "A good shot" 20th C Ireland.
Reply #15 - Nov 9th, 2021 at 1:35am
 
joe_meadmaker wrote on Nov 8th, 2021 at 10:41pm:
I imagine a camera would need to be pretty close to confirm the coin is actually being hit too.


we forgot something, for most cases I'd say beyond 20m 4k won't be enough to capture hitting the coin well enough so the camera has to be behind the coin or have multiple cameras. once again filming complicates things.
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Archaic Arms
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Re: "A good shot" 20th C Ireland.
Reply #16 - Nov 9th, 2021 at 8:21am
 
joe_meadmaker wrote on Nov 8th, 2021 at 10:41pm:
@Archaic Arms - In the setup of the contest you've described, do you think hitting the stake itself would disqualify a hit?  If not, I imagine a camera would need to be pretty close to confirm the coin is actually being hit too.  Just curious if you were envisioning the coin being knocked off without contacting the stake or not.

I'm thinking that if the projectile hits within the circumference of the coin, then it counts. Lets say the projectile hits the top of the stake where the coin is attached, if the projectile would have hit the coin (imagine the coin floating in mid-air) then it counts.

There would also have to be a rule regarding projectile size e.g. no bigger than a tennis ball, for example.



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Re: "A good shot" 20th C Ireland.
Reply #17 - Nov 9th, 2021 at 8:32am
 
Sarosh wrote on Nov 9th, 2021 at 1:35am:
we forgot something, for most cases I'd say beyond 20m 4k won't be enough to capture hitting the coin well enough so the camera has to be behind the coin or have multiple cameras. once again filming complicates things.

There are three ways this can be overcome.

1st:
Put camera downrange and hope for the best, with risk of seeing something similar to this (followed by permanent darkness):https://youtu.be/rKhcPr1yjEs?t=9
2nd:
Put camera downrange with protection e.g plexiglass or something in that vein
3rd: (and much better solution)
Film through a binocular, monocular, rangefinder, or anything that zooms in objects at a distance. This should work very well as these are not extended ranges, so even a cheap monocular should suffice.
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joe_meadmaker
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Re: "A good shot" 20th C Ireland.
Reply #18 - Nov 9th, 2021 at 9:44am
 
A 4th option could be to put the camera downrange behind a tree or other large obstruction, and turned at an angle so it's facing the target.  If there's a barrier in front of your camera, it won't get hit.  The only problem with this is the barrier will also block the slinger from being in the recording.  So only the actual target hit will be on camera.
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Re: "A good shot" 20th C Ireland.
Reply #19 - Nov 11th, 2021 at 1:09pm
 
Archaic Arms wrote on Nov 8th, 2021 at 2:08pm:
joe_meadmaker wrote on Nov 6th, 2021 at 7:12pm:
But I think your stated distance of 100 yards is too far. 

You're definitely right. After testing this in the field, one would need that thing to be shining like a beacon in order to see it...


Well I'll be damned. Went up on the hill today to do give coin spotting another go, and I put the 10p coin one of the banks of the iron-age hillfort (so it had a dark soil back ground). I walked as far away as I possibly could from it, turned around, and still saw it very clearly. That was at a distance of 125yds (using google earth).
Now I need to find a longer range to see at what distance it actually disappears...
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Re: "A good shot" 20th C Ireland.
Reply #20 - Nov 11th, 2021 at 1:17pm
 
Sorry for the size, but if it's shrunk you won't be able to see the coin.
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Sarosh
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Re: "A good shot" 20th C Ireland.
Reply #21 - Nov 11th, 2021 at 3:06pm
 
i see it's cloudy, is the sun at your 12:00? was the coin in the shadow or it could reflect the sky?do I need to change glasses? lol
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Re: "A good shot" 20th C Ireland.
Reply #22 - Nov 11th, 2021 at 3:42pm
 
Sarosh wrote on Nov 11th, 2021 at 3:06pm:
i see it's cloudy, is the sun at your 12:00? was the coin in the shadow or it could reflect the sky?do I need to change glasses? lol

Yes I think the sun was a bit to the left of the brightest part of the sky. The coin was propped up so that it was facing me almost square on (it may have been very slightly tilted back). I have a few more photos.
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Re: "A good shot" 20th C Ireland.
Reply #23 - Nov 11th, 2021 at 3:51pm
 
One taken a bit closer...
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10p_coin_at_70yds_2.jpg (2970 KB | 44 )
10p_coin_at_70yds_2.jpg

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NooneOfConsequence
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Re: "A good shot" 20th C Ireland.
Reply #24 - Nov 12th, 2021 at 11:24am
 
Well… you can see “something shiny” but if you didn’t already know that coin was there, you wouldn’t be able to identify the target… especially if there are other reflective objects in the environment.

There seems to be a specific need in this case for a more pedantic definition of “see”.
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“My final hour is at hand. We face an enemy more numerous and cunning than the world has yet seen. Remember your training, and do not fear the hordes of Judas. I, without sin, shall cast the first stone. That will be your sign to attack! But you shall not fight this unholy enemy with stones. No! RAZOR GLANDES!  Aim for the eyes! May the Lord have mercy, for we shall show none!“  -Jesus the Noodler
 
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Sarosh
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Re: "A good shot" 20th C Ireland.
Reply #25 - Nov 12th, 2021 at 12:08pm
 
NooneOfConsequence wrote on Nov 12th, 2021 at 11:24am:
Well… you can see “something shiny” but if you didn’t already know that coin was there, you wouldn’t be able to identify the target… especially if there are other reflective objects in the environment.

There seems to be a specific need in this case for a more pedantic definition of “see”.


one definition would be if I can point it to you and you can recognize it and you didn't know I put it there then you can "see" it. Another definition would be
yes
if you can see it is a coin and not a pebble, but it will be
difficult/almost no
if you can focus on it but you are not sure what it is.
no
is if I point it to you and you cannot see it.

there is a curious case when for example you can clearly see a fence but if I tell you to focus on the 50th railing then there is a distance between railings which you can clearly see 50th railing but not focus on it.
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IronGoober
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Re: "A good shot" 20th C Ireland.
Reply #26 - Nov 12th, 2021 at 12:24pm
 
If you look up the resolving power of the human eye, it is  about 20 arcsec (from the diffraction limit and the size of the aperture of the human eye, i.e. pupil.) but it is less in actuality due to eye aberrations.  But if we assume 20 arcsec, that's about 2.8e-4° or 9.7e-5 radians.  Using the approximation sin(theta)=theta (i.e. object radius/distance = theta), you can calculate the size of the object that one should be able to see.

So for a 1" coin, --> r=1.27cm, solve for distance, ~13092cm, or 130m.  That is a best case scenario if you had absolutely perfect eyes. It will be much less than that in practice, depending on your eyes, likely 1/2 or a 1/3 of that.

For something that is shiny and that diffusely reflects light, you will be able to make it out just from the reflection, but you won't actually be able to resolve it (i.e make out the shape). You'll only be limited in distance by how low of light intensity you can detect (as the light intensity will fall off 1/r^2). I think that is what you were detecting was the diffusely scattered light from the coin.
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IronGoober
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Re: "A good shot" 20th C Ireland.
Reply #27 - Nov 12th, 2021 at 12:26pm
 
Sarosh wrote on Nov 12th, 2021 at 12:08pm:
here is a curious case when for example you can clearly see a fence but if I tell you to focus on the 50th railing then there is a distance between railings which you can clearly see 50th railing but not focus on it.


This is called "resolution" in optics. You can see something is there, but you can't resolve it (the fence post).

That is what we should use as the definition, is can you resolve the coin. It the scientifically accepted definition when talking astronomy, microscopy, etc.
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Re: "A good shot" 20th C Ireland.
Reply #28 - Nov 12th, 2021 at 3:07pm
 
IronGoober wrote on Nov 12th, 2021 at 12:24pm:
So for a 1" coin, --> r=1.27cm, solve for distance, ~13092cm, or 130m.  That is a best case scenario if you had absolutely perfect eyes. It will be much less than that in practice, depending on your eyes, likely 1/2 or a 1/3 of that.


40m seems like a sufficient challenge especially considering that the modern competitive definition of a “good shot” is a 50cm Diana at 20m.
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“My final hour is at hand. We face an enemy more numerous and cunning than the world has yet seen. Remember your training, and do not fear the hordes of Judas. I, without sin, shall cast the first stone. That will be your sign to attack! But you shall not fight this unholy enemy with stones. No! RAZOR GLANDES!  Aim for the eyes! May the Lord have mercy, for we shall show none!“  -Jesus the Noodler
 
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Re: "A good shot" 20th C Ireland.
Reply #29 - Nov 12th, 2021 at 3:18pm
 
Also… what metal was a shilling made from at the time? Copper? If so, then unless it’s polished, you can’t rely on the shiny factor. A nice layer of oxidation would dull the surface.
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“My final hour is at hand. We face an enemy more numerous and cunning than the world has yet seen. Remember your training, and do not fear the hordes of Judas. I, without sin, shall cast the first stone. That will be your sign to attack! But you shall not fight this unholy enemy with stones. No! RAZOR GLANDES!  Aim for the eyes! May the Lord have mercy, for we shall show none!“  -Jesus the Noodler
 
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