185. Anatomy of a Camera Lens

by Jarvo J May. 20, 2009 26688 views

I've always thought that lenses were greatly over-priced. How can they justify the price tages that come with them? It wasn't until I stripped this one down, that I realised just how much technology they contain. The lens shown here is the 50mm 1.8; it is the cheapest lens in the Canon catalogue. I expect that more expensive lenses contain more technology, but I'm not looking to break a more expensive one just to find out.

The true nature of lenses - upside down images.

Proof, if it were needed, that you can reverse a standard lens to take macro images.

This is how it's done. Mine is a poor image bacause I just lined the lenses up, but for less than a tenner you can buy a specially made coupler ring (sorry about the quality of this shot too, but it's hard taking a picture of yourself holding one camera at arm's length whilst looking through another).

The six main parts of the lens laid out. Please hover cursor over the picture for labels. Note, that as this is a very simple fixed lens so there's only two pieces of glass. If anyone fancies dismantling a very expensive zoom lens, I'd love to see how many they have.

The six again, but this time in order from front to back.

The circuit board. I don't know what bits do what, with the exception of the little round disk at the bottom. This controls the flow of electricity into the motor via some brushes on the back.

The drive mechanism. Because it's only a cheap lens, this is made of plastic. The cog in the bottom right hand corner controls the auto focus. When it is disengaged (as in the picture) focus is manual. When it is engaged (imagine it pushed to the left a bit in the picture), the auto focus works.

Same mechanism, different angle.

The motor. The whole thing is just 20mm from top to bottom.

The focussing mecanism. Movement of the plastic block “A” in the groove “B” is what causes the front lens element to move in and out.

The aperture half way open. Being a cheap lens, it only has 5 diagphram blades. Pay more - get more. The slider to the right is what controls the aperture,

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There are 13 comments , add yours!
Ricardo 11 years, 8 months ago

thanks God, Jon did this to me!:D
I dont need to break any lens to see how it is made now! :)

11 years, 8 months ago Edited
Gillian 11 years, 8 months ago

Is no piece of equipment safe in your house? Hard drives, lenses .......

11 years, 8 months ago Edited
Mehdi Saharkhiz 11 years, 8 months ago

Such a cool post

11 years, 8 months ago Edited
Miclaud 11 years, 8 months ago


11 years, 8 months ago Edited
Gerd Korts 11 years, 8 months ago

Well, I have an expensive one but after your set for sure I will simply believe that 10 or so lenses are inside :-))

11 years, 8 months ago Edited
Brian 11 years, 8 months ago

Cool set! Very interesting to see all the different parts and you got some great closeups of these.

11 years, 8 months ago Edited
Sandra Vermeulen 11 years, 8 months ago

I share the opinion of Ruth,
I dare not think for disassemble one of my lenses ...
Restore would not work for me.
Did you get the lens back together or was that not intended? :o)

11 years, 8 months ago Edited
Netii 11 years, 8 months ago

wow very instructive set :)

11 years, 8 months ago Edited
Jet28 11 years, 8 months ago

Fascinating post! I always loved pulling things apart - you've saved me the trouble :-)

11 years, 8 months ago Edited
Paul 11 years, 8 months ago

Great shots ......Did you put it back together again?....and if you did how many bits were left over???

11 years, 8 months ago Edited
Marsha 11 years, 8 months ago

No way! All of that is in that one little lens? I have a 50mm Canon lens and I would have never guessed. Awesome work, Jon...shots are amazing and information is fascinating.

11 years, 8 months ago Edited
Michael Sakowicz 11 years, 8 months ago

Very interesting. I would never have the guts to take a lens apart.

11 years, 8 months ago Edited
Hajnalcsillag 11 years, 8 months ago

Dear Jon, how interesting! Just great that you took the effort of taking apart this photolens. Congrats. These photo's appeal to the most critical eyes. They're just fine. Bye

11 years, 8 months ago Edited
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