OK so silly Question ---- OR is it???

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stryvya

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If I stand in front of a Mirror, say 6ft away and want to take a Photo of myself, Stick with it please, I appear to be 12ft away but in fact the Image I`m seeing is only 6ft away, yes.

So without using the Viewfinder do I set the Lens to 6ft or 12ft or (even stranger) zero ft, because I`m taking a picture of where I`m standing. Your answers on a £20 note please.
 
12ft.



*** MOD EDIT : This is the Correct Answer, posts #3 onwards constitute the obligatory TP circular Argument, which you may wish to avoid wasting any of your valuable time on this earth reading
 
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If you're taking a photo of the reflection, then it's 6ft away.
 
Phil V said:
12ft.
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So in that case, if I get someone to stand six feet away from me and take a perfectly focused picture which I then print at life size and hang on a wall. If I stand six feet from the picture and take a picture of it, should I focus at 12ft? :confused:
 
Only a guess but I would say 6ft. but I can see the thought behind 12ft .... honest guess
 
I've just tried it. It is 6ft, presumably because the plane of focus is actually 6ft away from you and not 12ft as the reflection may imply.
 
BRASH said:
I've just tried it. 6ft it is presumably because the plane of focus is actually 6ft away from you and not 12ft as the reflection may imply.
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and would you like to tell us the results ?
 
KIPAX said:
and would you like to tell us the results ?
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I just did. 6ft not 12ft. At least I think that answers the OP's question.
 
Nevertheless I'm voting for 12ft.

Stick a sticker on the mirror. It will not be sharp when your image is sharp.
 
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BRASH said:
I just did. 6ft not 12ft. At least I think that answers the OP's question.
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I meant was the pic ion focus? if you focus at 6ft and it should eb 12 then.... well... hmmm I thought that was the question.. which would be in focus?
 
KIPAX said:
I meant was the pic ion focus? if you focus at 6ft and it should eb 12 then.... well... hmmm I thought that was the question.. which would be in focus?
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Yeh, 6ft. Well worked for me 24-105 lens @ f/8 the image was in focus.
 
Barrysprout said:
So in that case, if I get someone to stand six feet away from me and take a perfectly focused picture which I then print at life size and hang on a wall. If I stand six feet from the picture and take a picture of it, should I focus at 12ft? :confused:
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Try it with a mirror, I'm sure you've got one handy. It's about the simplest experiment in the world and has naff all to do with a printed 2d image.
 
stryvya said:
My thoughts, but does`nt that also defy the Logic that the image is 6ft away??
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No.. the light from YOU has travelled 12ft. The mirror being optically flat has just reflected it back without changing anything. As Phil has discovered... if you focus 6ft, the MIRROR will be in focus, but you will not.
 
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BRASH said:
Guess ffs, I just did it and that's the result I got how is that a guess?
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I said "good guess KIPAX"......and furthur up the thread I post my guess is 6ft ..... I dunno haha :) you probably just reasd the thread too fast :)
 
KIPAX said:
I said "good guess KIPAX"......and furthur up the thread I post my guess is 6ft ..... I dunno haha :) you probably just reasd the thread too fast :)
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Tony, you are incorrect. He did not read the thread too fast,he is simply an oaf.
 
In the old days, when manual focus was the norm, this was covered in all the beginners photo books.
 
Back on track now, well it seemed to work for me at 6ft both mirror and and me in focus. It was just a quick try mind.
 
BRASH said:
Yeh, 6ft. Well worked for me 24-105 lens @ f/8 the image was in focus.
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At f8. You might need to have a closer look, I tried at 1.8. And I can categorically tell you that you're wrong. What's more, I'm gobsmacked that everyone else didn't try for themselves.
 
You 'blinking' oaf! Perhaps? Excuse my language.

Anyway, this doesn't apply to vampires. I'm told. They use a mirrorless cameras I understand.
 
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Phil V said:
At f8. You might need to have a closer look, I tried at 1.8. And I can categorically tell you that you're wrong. What's more, I'm gobsmacked that everyone else didn't try for themselves.
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I don't have a 1.8 lens so can't try that but at f/8 it looks fine (apart from me being the subject:)). Like I said just a quick try, handheld, no exact measurements or scientific set up. Just did it out of interest because I was intrigued by the question, never thought about it before. Obviously never read the right books. I must learn to read!!
 
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I rest my case m'lud.
 
The image on the mirror is 6 feet away BUT is not in focus, you need to focus at 12 feet to get a clear image.
As Phil says it is quite basic and easy to try.

As an example when you go to the optician you sit in a darkened room and look at a reflected image, the mirror is 10 feet away so you are actually focusing 20 feet away to get the image clear. Once your eyesight is adjusted to see the 20 foot distant images clearly in both eyes you have 20/20 vision.
 
looking at a mirror right now and everything is in focus front to back, so 6ft
 
stryvya said:
My thoughts, but does`nt that also defy the Logic that the image is 6ft away??
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The image is not 6 feet away. The reflected light from you reaches the mirror 6 feet away but the light from every single part of you is spread across the whole of the mirror, the reflected light from one pore, for example, spreads out and reaches the whole of the surface of the mirror. There is not, therefore, a recognisable image on the mirror. Your eye needs to focus at 12 feet in order to sort out all the jumbled up light waves and create an image of your reflection.

Just to add to the above.
If you look at someone 12 feet away (no mirrors involved :)) the light from every part of them them spreads everywhere and gets jumbled up but your eye bends the light rays so that you see a clear image.

If you could measure the direction and intensity of the jumbled up light rays when they are 6 feet away from you as they travel towards you then you would get the same pattern as that which exists on the mirror in the original question.
 
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Step away from the computer :eek: and go outside, with a friend and a mirror. Have friend hold mirror, 6 feet away, so you can view a distant landscape in the mirror. Now focus on the mirror or, probably easier, your friend who is also 6 feet away. And the distant landscape scene is?
 
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