Focal length question

Re post 42--Absolutely. This is exactly why I posted my own doubts in post 23. I added the smilie in the hope that I am wrong but nothing since has persuaded me I was. :(

If this is some sort of bizarre experiment or trolling it's a shame, as many people have offered very generous help, even including a phone number. Kudos to the contributors.

Thomas: how does discovering that there are 1000 millimetres in a metre answer your question?
 
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Oh dear...

'So when an artist named Ann Jemima Provis and her father, Thomas Provis, approached West and told him they had found a copy of an old manuscript that explained how the Venetians achieved their distinctive style of painting, he jumped at the chance to learn more. Eager to incorporate the methods in the manuscript into his own work, West began experimenting with them.

There was only one problem.

“The story was an absurd invention, and the manuscript was a fake,” said Angus Trumble, senior curator of paintings and sculpture at the Yale Center.'
​
http://www.nytimes.com/2008/08/31/arts/design/31bier.html?pagewanted=all&_r=0

So should I claim my five pounds? :)
 
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Hey folks - calm down a bit please. He's not trolling or anything like that - he's my son!

He's 13 years old and asking questions about something that he is interested in. Nothing wrong with that. If you have a problem with an inquisitive 13 year old then please keep your opinions to yourself.
Many of the answers here have not been clear and maybe neither has his question. He's been a bit blinded by answers that all.
Now please, if you cannot offer anything constructive to a 13 year old who wants to learn, then please say nothing and do not accuse him of trolling.
Thank you.
 
The "friendliest" photography forum strikes again.
 
guess&press said:
Oh dear...

'So when an artist named Ann Jemima Provis and her father, Thomas Provis, approached West and told him they had found a copy of an old manuscript that explained how the Venetians achieved their distinctive style of painting, he jumped at the chance to learn more. Eager to incorporate the methods in the manuscript into his own work, West began experimenting with them.

There was only one problem.

“The story was an absurd invention, and the manuscript was a fake,” said Angus Trumble, senior curator of paintings and sculpture at the Yale Center.'
​
http://www.nytimes.com/2008/08/31/arts/design/31bier.html?pagewanted=all&_r=0

So should I claim my five pounds? :)
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What on earth are you trying to say here?
Do you have a problem with the name I chose for my son or the surname that was handed down to me by my parents?
As my previous post says - if you can't help a 13 year old - don't say anything. Your comments are not welcome.

And yes you can report this post to the moderators if you so wish because any more abusive posts towards my son and I will report it myself!
 
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Welcome to talk phptography the welcomeforum said. Enjoy your self they said. Friendly place to be they said. Well someone obviously got something wrong there, because judging by the replies to my normal question that I admit. Makes no sense. This forum doesn't look so appealing and friendly anymore.
 
JulesP said:
Hey folks - calm down a bit please. He's not trolling or anything like that - he's my son!

He's 13 years old and asking questions about something that he is interested in. Nothing wrong with that. If you have a problem with an inquisitive 13 year old then please keep your opinions to yourself.
Many of the answers here have not been clear and maybe neither has his question. He's been a bit blinded by answers that all.
Now please, if you cannot offer anything constructive to a 13 year old who wants to learn, then please say nothing and do not accuse him of trolling.
Thank you.
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You wouldn't reply like this to other peoples questions would you. So why has everyone got arsey with thread? Is it because I'm 13? It it because I'm new? Like my dad says. I'm asking questions about what I like doing. Nkthing different to what you've ever done !!!!!
 
Ulfric M Douglas said:
This is some kind of A.I. experiment, check this ;

which is absolutely bizarre because J.crosseley actually said this ;


Post count?
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Well thanks a lot. What I reply to peoplez posts doez not affect you. Id apreciate it if you dont say things like that about/towards me. Wht I post has nothing to do with you. I read the awnsed wrong and thought it ment something else. So in future. Please do not say thngs like this.
And yes. I will relply and quote every post I see that has abuse or hate in it.
 
When it comes to translating zoom to focal length, doesn't the image sensor size matter also? (i.e. crop factor)

For example my bridge camera has a tiny compact sized sensor but has a 50x zoom lens. There's 35mm equivalent markings on it saying that it goes from 24mm - 1200mm. So I take it this means that the lens itself isn't the equivalent of a 1200mm lens that would be use on a full frame camera (there's a bit of a physical size difference lol), but taking into account the crop factor then the actual image you are seeing would be the same as sticking a 1200mm on a full frame DSLR?

That probably doesn't sound very clear but lets just say I could remove the lens from my bridge camera and stick it on a 35mm full frame DSLR camera. It wouldn't be able to zoom to 1200mm because the sensor is so much bigger. So imagine you took a photo with that lens at full zoom of a person standing in distance with that lens on a camera that has a full sized sensor and that person is now in the middle of the photo and quite small.

Then if you were to imagine placing the tiny sensor of the bridge camera onto that photo where the person is and say it only covers their head. This basically shows how much zoom you would get when taking into account the crop factor of a smaller sensor. So if you were to then put that lens onto the bridge camera (which has the small sensor) and took the same photo at full zoom the photo would be filled with just that person's head. (check out this for a similar example: http://www.onlinevideo.net/wp-content/uploads/sensor_crop.jpg)

So if you are wanting to know how to compare advertised zoom levels on a compact or bridge camera against a DSLR you also have to take into account the sensor size.

Here's an example of my bridge camera fully zoomed and underneath is a photo of a 1200mm lens for a full frame DSLR. There's quite a difference in length! lol

I'm not sure if this helps answer your question or even if I've picked up what you are asking correctly but either way it's something to know I guess? :)


Sony-HX400-front-34R-600.jpg


00610cceadde.jpg
 
Here's a video which may help:

 
Ulfric M Douglas said:
What would you like me NOT to say? ... In future, that is.
Be careful, your post almost got reported for its abusive attitude.
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Please see my post number 46. As I said - he's my 13 year old son and asking questions that may not be clear but he is trying to learn. He has received some help here but also what I consider some unwelcome and unhelpful replies.
If you want to report it - go ahead

EDIT - I've reported it to get it locked.
 
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lots of helpful answers, and a couple of not helpful answers, and a question that wasnt very clear.

Lots of friendly helpful stuff in this thread though, so its not all bad.
 
I actually found the subject of this thread quite interesting - something I too was wondering, as someone just 1 year younger than Thomas (interestingly, we both share the name Thomas, too!)
The question was worded confusingly, but I think it's clear now that he's interested in "what will I see through an x mm lens?"

Thomas,

Everyone seemed to have good intentions in this thread :) Hopefully your answer is clear to you after some of the posts. Because of the confusing nature of how it was worded, I guess people just got a little inquisitive in to what you meant and posted things that read differently to how they mean, in the heat of a moment. Everything here seems mostly friendly, just as with any online communication, messages can get a bit mixed up which leads to things getting a little troubled.

If you're still confused, feel free to message me on Skype, I think I understand it now, and I'd be glad to try and explain it to you.
 
Tom Farrow said:
The question was worded confusingly, but I think it's clear now that he's interested in "what will I see through an x mm lens?"
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The best way to think about this is to consider it as an angle of view. To work this out you need two things. The focal length of the lens and the length of the long side of the film or sensor - then draw a triangle.

e.g. for a 50mm lens of full frame digital (or 35mm film) draw a line 36mm long then draw another line from the middle of the first line and perpendicular to it, 50mm long.

Join up the two open sides to form a triangle. The angle between the two sides either side of the 50mm line is the angle of view.

If you do this on CAD you can measure the angle and stretch the focal length to see how the angle of view changes.


Steve.
 
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Tom Farrow said:
I actually found the subject of this thread quite interesting - something I too was wondering, as someone just 1 year younger than Thomas (interestingly, we both share the name Thomas, too!)
The question was worded confusingly, but I think it's clear now that he's interested in "what will I see through an x mm lens?"

Thomas,

Everyone seemed to have good intentions in this thread :) Hopefully your answer is clear to you after some of the posts. Because of the confusing nature of how it was worded, I guess people just got a little inquisitive in to what you meant and posted things that read differently to how they mean, in the heat of a moment. Everything here seems mostly friendly, just as with any online communication, messages can get a bit mixed up which leads to things getting a little troubled.
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A fine post young man.:agree:
 
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