625 Meter Beamshots Of Many Vinh Lights And Others

blerkoid

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Awesome, thank you! I look forward to seeing more of your work in the future.
 

TEEJ

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I really like the way you did the shoot.

The two camera set up really helped immensely, especially as the long range shots set up the context, but w/o the closer range shot, the posted pics could not really show the target in enough detail to tell anything about them. We had discussed using a closer camera in the DEFT-X thread too for example, as at one mile ranges, even telephoto lenses are hard presed to show good detail, especially in low light.

The next evolution would be to also have a light meter on the target, to get the actual lux on target to go with the level of illumination.

set-72157635768624506
 

Hot Brass

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"The next evolution would be to also have a light meter on the target, to get the actual lux on target to go with the level of illumination."
That would be interesting using the ANSI/NEMA FL-1 measuring standard for beam distance....I would like to actually see what one can see,if anything,at a certain distance while producing .25 Lux. Thanks,HB
 
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TEEJ

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"The next evolution would be to also have a light meter on the target, to get the actual lux on target to go with the level of illumination."
That would be interesting using the ANSI/NEMA FL-1 measuring standard for beam distance....I would like to actually see what one can see,if anything,at a certain distance while producing .25 Lux. Thanks,HB

I have done measurements of this actually.

In most real life situations, at long ranges, you can not resolve much with 0.25 lux on a target. At close ranges, 0.25 lux is plenty to see at least basic details.

Essentially, at close ranges, the image is a proportionally large part of our field of vision. At long ranges, the image is a proportionally small part of our field of vision.

When we are trying to see details at long ranges, say at 1,000 meters for example, we need to use the sharpest part of our vision, called our fovea. This is what we instinctively narrow our vision to when we squint to see fine details/distant targets, etc. Unfortunately, the fovea, while providing our best color vision and ability to track moving targets and resolve fine details, is TERRIBLE in low light scenarios, requiring FAR more light to see than the rest of our field of view needs. THIS is one reason that long range illumination simply requires more light than close range illumination does, to see the same target.



A real life observation of the effect involves one guy off in the remote distance, holding a book....and another with a long range flashlight pointed at him, from a long way away.

The guy with the flashlight can't tell there's a guy with a book out there, as 0.25 lux is too little illumination to resolve him via fovea. The guy with the book has enough light to read by - from that other guy's flashlight, because there IS enough light to read by if close enough to the book...even if the guy with the flashlight can't even see the guy OR the book, etc.

:D



Add the question of HOW night adapted the observer's vision is, and the RANGE of illumination required to resolve adequate details varies greatly. For example, many of us have tried to do daylight chores indoors, and felt the need to turn on all the lights in a room to be able to see well enough....but in the same room found even one light turned on at 3 am was glaringly bright, to the point of causing pain and essentially, and ironically, blindness, until our eyes have a chance to adjust and stop down our pupils enough to see again, etc.

I have tritium vials of varying output, and, the glow from a small key chain fob sized vial is invisible during the day, but can cast shadows in the middle of the night when its glow becomes VERY noticeable, even allowing us to see nearby objects/read by.


The same issue is at play with a flashlight used for long distance searches, etc. If you have too much illumination close to you, your pupils contract/lose night adapted vision. (There are chemical changes too, etc...). Your BEST night vision for a distant target is where the illumination is more like you'd get from a theater spot light...the target is glowing, and every thing ELSE is dark.

If the light is putting TOO MUCH light on the target, even if ONLY on the target, the same effect happens, and your eyes adjust, and you then need MORE light to resolve the same details on OTHER targets, and so forth. This is one reason that choosing the right light (in a search scenario for example) is more akin to choosing the best club to use on a golf course, so that you can put the best amount of light on the best combination of search field of view.


IE: Typically, if looking for something expected to be found closer to you, say in terrain where you simply don't have any long lines of sight, you want a flood-type beam, so you can naturally see as much as possible at a time. If looking for things so far away that no flood pattern can REACH that far, you narrow the beam profile until the resultant beam has the juice to hit targets with enough light to resolve what needs to be resolved.


A low contrast target (Something not reflective, the same colors as the background), even at 200 meters, might require over 15 lux to resolve it. A large enough white target at the same range might be visible with 0.3 - 1.0 lux or so....but require more than that to tell anything ABOUT the target.
 

Hot Brass

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I have done measurements of this actually.

In most real life situations, at long ranges, you can not resolve much with 0.25 lux on a target. At close ranges, 0.25 lux is plenty to see at least basic details.

Essentially, at close ranges, the image is a proportionally large part of our field of vision. At long ranges, the image is a proportionally small part of our field of vision.

When we are trying to see details at long ranges, say at 1,000 meters for example, we need to use the sharpest part of our vision, called our fovea. This is what we instinctively narrow our vision to when we squint to see fine details/distant targets, etc. Unfortunately, the fovea, while providing our best color vision and ability to track moving targets and resolve fine details, is TERRIBLE in low light scenarios, requiring FAR more light to see than the rest of our field of view needs. THIS is one reason that long range illumination simply requires more light than close range illumination does, to see the same target.



A real life observation of the effect involves one guy off in the remote distance, holding a book....and another with a long range flashlight pointed at him, from a long way away.

The guy with the flashlight can't tell there's a guy with a book out there, as 0.25 lux is too little illumination to resolve him via fovea. The guy with the book has enough light to read by - from that other guy's flashlight, because there IS enough light to read by if close enough to the book...even if the guy with the flashlight can't even see the guy OR the book, etc.

:D



Add the question of HOW night adapted the observer's vision is, and the RANGE of illumination required to resolve adequate details varies greatly. For example, many of us have tried to do daylight chores indoors, and felt the need to turn on all the lights in a room to be able to see well enough....but in the same room found even one light turned on at 3 am was glaringly bright, to the point of causing pain and essentially, and ironically, blindness, until our eyes have a chance to adjust and stop down our pupils enough to see again, etc.

I have tritium vials of varying output, and, the glow from a small key chain fob sized vial is invisible during the day, but can cast shadows in the middle of the night when its glow becomes VERY noticeable, even allowing us to see nearby objects/read by.


The same issue is at play with a flashlight used for long distance searches, etc. If you have too much illumination close to you, your pupils contract/lose night adapted vision. (There are chemical changes too, etc...). Your BEST night vision for a distant target is where the illumination is more like you'd get from a theater spot light...the target is glowing, and every thing ELSE is dark.

If the light is putting TOO MUCH light on the target, even if ONLY on the target, the same effect happens, and your eyes adjust, and you then need MORE light to resolve the same details on OTHER targets, and so forth. This is one reason that choosing the right light (in a search scenario for example) is more akin to choosing the best club to use on a golf course, so that you can put the best amount of light on the best combination of search field of view.


IE: Typically, if looking for something expected to be found closer to you, say in terrain where you simply don't have any long lines of sight, you want a flood-type beam, so you can naturally see as much as possible at a time. If looking for things so far away that no flood pattern can REACH that far, you narrow the beam profile until the resultant beam has the juice to hit targets with enough light to resolve what needs to be resolved.


A low contrast target (Something not reflective, the same colors as the background), even at 200 meters, might require over 15 lux to resolve it. A large enough white target at the same range might be visible with 0.3 - 1.0 lux or so....but require more than that to tell anything ABOUT the target.

Thanks! What would you say were the lux readings (guesstimate) at the 625 meter targets,which ever one seems brighter to you. Thanks,HB
 

rdrfronty

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We actually want to try to do this again tonite, but at a longer distance and take some measurments at the target this time too. We've experimented many times in the past with lux reading at distances and they usually read surprising close to lux readings taken at normal 5-15m range. We've done this before at up to 700m ranges and got good readings. Nights with lots of moisture/humidity have effected the readings before though.
Anyway, i know we can go up to 800m in the pipeline target area for sure. The elevation and trees start becoming an issue when it it much further than that. Hopefully we can squeeze 1000m out of the place. I love the area being in the middle of a national forest miles away from anything, so no ambient light at all. And the moon will be basically down too 2% illumination tonite too and will be below the horizon to boot, so should be nice and dark. And no bad weather in the forcast. We actually use a cool app for moonrise and setting to keep track moon. We usually aim to beamshots when the moon is below the horizon or well below 50% illumination. Makes cooler shots. And much better for distances pushing the limits of the lights reach.
So we'll see what we make happen tonite.
 
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Hot Brass

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We actually want to try to do this again tonite, but at a longer distance and take some measurments at the target this time too. We've expepiremented many times in the past with lux reading at distances and they usually read surprising close to lux readings taken at normal 5-15m range. We've done this before at up to 700m ranges and got good readings. Nights with lots of moisture/humidity have effected the readings before though.
Anyway, i know we can go up to 800m in the pipeline target area for sure. The elevation and trees start becoming an issue when it it much further than that. Hopefully we can squeeze 1000m out of the place. I love the area being in the middle of a national forest miles away from anything, so no ambient light at all. And the moon will be basically down too 2% illumination tonite too and will be below the horizon to boot, so should be nice and dark. And no bad weather in the forcast. We actually use a cool app for moonrise and setting to keep track moon. We usually aim to beamshots when the moon is below the horizon or well below 50% illumination. Makes cooler shots. And much better for distances pushing the limits of the lights reach.
So we'll see what we make happen tonite.

Looking forward to some lux readings at those distances for sure! Thanks,HB
 

TEEJ

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We actually want to try to do this again tonite, but at a longer distance and take some measurments at the target this time too. We've expepiremented many times in the past with lux reading at distances and they usually read surprising close to lux readings taken at normal 5-15m range. We've done this before at up to 700m ranges and got good readings. Nights with lots of moisture/humidity have effected the readings before though.
Anyway, i know we can go up to 800m in the pipeline target area for sure. The elevation and trees start becoming an issue when it it much further than that. Hopefully we can squeeze 1000m out of the place. I love the area being in the middle of a national forest miles away from anything, so no ambient light at all. And the moon will be basically down too 2% illumination tonite too and will be below the horizon to boot, so should be nice and dark. And no bad weather in the forcast. We actually use a cool app for moonrise and setting to keep track moon. We usually aim to beamshots when the moon is below the horizon or well below 50% illumination. Makes cooler shots. And much better for distances pushing the limits of the lights reach.
So we'll see what we make happen tonite.

LOL

I see that too, essentially, the inverse square law thing seems to work in practice. And, yup, schmootz in the air drops the lux, and, the more schmootz, and the more distance THROUGH the schmootz the beam has to get through to hit the target, the lower the lux when it finally gets there.

:D
 

ven

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@rdrfronty-thank you for taking the time and effort for all of this,it is greatly appreciated:twothumbs

Just driving a few miles up the road with a few lights for amateur at best pics proved hard work in itself ..........

So big THANKS
 

rdrfronty

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@rdrfronty-thank you for taking the time and effort for all of this,it is greatly appreciated:twothumbs

Just driving a few miles up the road with a few lights for amateur at best pics proved hard work in itself ..........

So big THANKS
Truthfully we enjoy doing it anyways. Just gives us another "justified" reason for two grown men to go running around in the woods playing with flashlights :)
 

ven

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Truthfully we enjoy doing it anyways. Just gives us another "justified" reason for two grown men to go running around in the woods playing with flashlights :)


:laughing: so true:thumbsup: hope all goes to plan for you both;)
 

CyclingSalmon14

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WOW these are awomse, and put my effort to complte shame ofcourse, cleaerly so much work went into this!

Thanks for doing this!
 

Patt

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Hi rdrfronty..:wave: I have a question..(just wonder)..but 1st wanna say... :goodjob::clap: thx...awesome ..

Do you do your testings wit high drain..fully charged battery's I suppose or ..not? :lolsign: Well done bro... :clap::twothumbs:twothumbs:thanks:
 

rdrfronty

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Hi rdrfronty..:wave: I have a question..(just wonder)..but 1st wanna say... :goodjob::clap: thx...awesome ..

Do you do your testings wit high drain..fully charged battery's I suppose or ..not? :lolsign: Well done bro... :clap::twothumbs:twothumbs:thanks:
All lights have quality cells at least 4.10v or more. Usually 4.20v if time allows. If the light needs high draw batteries, like the supershocker for instance, we run them in it. Usually 20R's. Most of the regulated lights, like tn31vn that doesn't benefit from high draw cells, i usually just run quality panasonic based cells.
 
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