How to tell how far something is

There is a way to tell how big something isn't by using a military technique that I've used many times myself.

It's helped me to tell if it is a bird, a plane or maybe, a UFO.

To do this, you need a scope. Yes, I said a scope. I carry one on me when I'm out hunting for UFO's. Using a scope with mil scale retical, you can figure this out.







If you have a brain and a piece of paper, anyone can figure this out.



There are many different type of scopes you can use for this, and some spotting scopes have this ability as well.



[edit on 24-4-2008 by Terrk]

reply to post by Terrk


Hello Terrk, glad to see you are back.

Now I have no military background, so I want to know what type of scope you are talking about.

Would that be a scope for a rifle, or????

Some call it a military trick, I call it the Pythagorean Theorum

You actually don't even need a scope, but I get your analogy and it's perfectly accurate. All you need to know are the locations of two points to find the distance between them But in real time, you're correct that most scopes have grids that help to determine distance.

Similarly the cameras that are used in surveying land have grids.

Here are a few links to help people understand how to determine distance after the fact. I've been itching at the bit to use these formulas in the Battle of LA thread (I still need to track down one of my locations, but I'm almost there).

math.about.com...
www.purplemath.com...


And here's some detail on Pythagorus
en.wikipedia.org...

-WFA

reply to post by WitnessFromAfar


Those are intersting links you have supplied. Thanks.

I live in an area where there is a lot of fog for a good portion of the day, and sometimes it is difficult to tell the distance of anything.

I look forward to reading further on this, as I saw something last week or so, and it was difficutle to judge the distance of it. I could only go by a tree line.

Here is a great place to look

www.burrisoptics.com...


They're binocs are great! I just use a scope off my old rifle and that works just fine.

Edited Double post

[edit on 23-4-2008 by Terrk]

Extremely intelligent post, well presented and well supported.

The only problem is that your answers are pointless.

You started the very first line of your post with the following line "I have seen a lot of pictures of ufos that people scream bird or some other object. "

Now just tell me how the hell a scope helps me determine how far something is in a picture? And who the hell carries a damn scope around with them everyday, and even if they do and they do spot something and do take a picture of it, were still left with "Do we believe that he is right about the distance he has worked out?"

Like I said, amazing post very informative and intelligent flagged and starred. But its completely irrelevant according to your first line which I assume was your kind of your mission statement for the thread, as if you were actually gonna solve that dilemma during the post. But you didn't.

Edit: Lol then I re-read your post and noticed the following line "It's helped me to tell if it is a bird, a plane or maybe, a UFO. "

Hahahahaha if you have a damn scope or binoculars then your eyes should do all the work for you hahahaha, remember those items help increase the size of an object to a recognizable size despite its great distance physically from your eye. Talk about defeating the purpose of your own post.



[edit on 24-4-2008 by king9072]

Sorry about that, I've been working for 20 hours and I'm a little sleepy, I'll edit it out, I'm not sure where I was going with that, but this deployment is really getting to me.

My bad.

WFA: It's not Pythagore's theorem, it's Thales' theorem.

I know several ways to tell how far a UFO is. For "something" in general, there are many more.

- Estimate distance to a known reference object close to the UFO or its shadow (when another object is seen in the background or foreground - tree, building, cloud, ...).

Two accurate geometric methods:
- If you know the size of the UFO (as in the OP), and the angle it makes in your image (easy to get if you know the field of view of the camera or scope - the model and zoom level of the camera must be known). For a UFO knowing the size is not likely, unless you have other information (on the ground, size of its shadow for example) to estimate the size of the UFO.
- If you have two pictures from two different observers at the same time, at a known distance, or if the camera is moved sideways between 2 pictures, and you assume the object is not moving in the same direction, you can get its parallax i.e. its apparent movement relative to the background (if there is a reference feature in the background whose distance is known), and deduce its distance.

Two much less reliable methods:
-if you know the material / texture / reflectivity of the object is similar to another object visible on the picture, whose distance is known, it is possible to compare the two apparent colors. The nearest object should be less affected by the (foggy) atmosphere, giving it a darker coloration.
- atmospheric disturbance. The image in a telescope of a distant object must be shimmering. It can be used by comparison for lights in the night sky. If they are as small as stars, but don't twinkle as stars, their light did not go through the entire atmosphere.

I'm sure there are other methods, less applicable for UFO. For example if you know the speed of the UFO (from Doppler effect sound or radar), you can get its distance from a video or two pictures with EXIF data.