What does mm mean on lenses. What is it actually measuring

[Kbarredo]

Sometimes the finger just slips in.

Hey now.. that sounds dirty!!

I was an electrician's helper. I had experience.

Arent you supposed to shut off the power when you mess around with the socket?

 

[bentcountershaft]

Why can't I have a thread that shows me what type of person I am? I mean, I know I'm an asshole, but I'm not the kind of asshole to ask someone what kind of asshole I am. I'm a completely different, yet to be identified asshole.

 

[dgadams2]

Why can't I have a thread that shows me what type of person I am? I mean, I know I'm an asshole, but I'm not the kind of asshole to ask someone what kind of asshole I am. I'm a completely different, yet to be identified asshole.

So... an unidentified asshole starting an asshole thread to find out what kind of asshole they are...

INCEPTION!!!!!!!!

 

[Bitter Jeweler]

Why can't I have a thread that shows me what type of person I am? I mean, I know I'm an asshole, but I'm not the kind of asshole to ask someone what kind of asshole I am. I'm a completely different, yet to be identified asshole.

You clearly don't post enough for judgements to be made. You are in community judgement limbo.

 

[Stryker]

Its the distance between the front of the lens and the camera sensor measured in millimeters (mm). The closer the front of the lens to the sensor, the wider the image and vice versa. That was the first thing I tried to learn before I bought my DSLR. In case you still find that difficult to understand, read this one: What do numbers letters on digital camera lens mean (Website Design Tips)

 

[Dao]

Its the distance between the front of the lens and the camera sensor measured in millimeters (mm).

Are you sure about that?

 

[Stryker]

correct me if i was wrong...

 

[bentcountershaft]

You clearly don't post enough for judgements to be made. You are in community judgement limbo.

Well, sh!t. Now I guess I'll have to go to the wiki page for different types of assholes and do a self analysis. You dirty bastages.

 

[analog.universe]

correct me if i was wrong...

I was pretty sure it was the distance from the no-parallax point at infinity focus to the sensor plane... although I'm not sure that's the correct term for the spot I'm thinking of. The place where the rays all cross in the lens when it's focused at infinity.

 

[Kbarredo]

So my question was not that simple at all.

 

[vtf]

Instead of complaining about your question, I'll refer you to this helpful diagram: Focal Length: Optical: Glossary: Learn: Digital Photography Review

(this forum sure is good at complaining though!)

Well no, I couldn't have answered it because to do so would have require typing a very long a complicated explanation, about something which has already been written about in great detail by people who understand it a lot better than I do. Did you even go to the wikipedia link?

It's just plain lazy and bad forum etiquette to expect people to bend over backwards and answer your questions in a way tailored to your personal level of understanding, when the information is all out there for you to find yourself.

Its also bad forum etiquette to complain and not contribute to a thread. If you dont like it dont look at it. If everyone just researched by themselves then this site would only be c&c. Is this not a beginners forum for those beginners who seek help. Am I not at a beginner skill level? I would rather be a lazy man than a smartass trying to start fights. At least I will contribute more because can read this thread if they are wondering he same thing. You on the other hand contribute nothing but sarcasm and complaints. So go ahead spend your time being a jerk its your loss. Just dont do it on my threads.

I would sure miss the drama, trolling threads.

And btw the way mm stands for Mighty Mouse!

 

[bazooka]

Its the distance between the front of the lens and the camera sensor measured in millimeters (mm). The closer the front of the lens to the sensor, the wider the image and vice versa. That was the first thing I tried to learn before I bought my DSLR. In case you still find that difficult to understand, read this one: What do numbers letters on digital camera lens mean (Website Design Tips)

If that were true, than many zoom lenses aren't zoom lenses at all, and I totally got ripped off on my 70-200.

 

[shortpants]

I believe it's the distance from somewhere in the center of the lens, to the sensor, but I don't know really.

 

[Dao]

correct me if i was wrong...

Image quoted from "http://www.the-digital-picture.com"

As you can see, the first 3 lenses from the left are 70-300mm lens. And they are set at 300mm in the photo. The front element (although cannot be seen from the photo because of the hood) extend differently.

 

[analog.universe]

It's simple for a lens with a single element, but camera lenses have many elements, as you can read from their spec sheets. The important part of the theory is that when you draw an isosceles triangle with the sensor at the base, and the focal length for the height, the resultant angles determine your field of view.