Why aren't all lenses macro?

[Canuk]

Cost prohibitive. The motor in a macro lens focuses slower as well. Not good for other things.

Just got the 100f2.8L Macro, I dont find it slow at all. The zooms that have the "macro" distinction may be slower, but most of those don't do 1:1 so are they really macros?

 

[brush]

Wowza, this bridge sure does have a lot of trolls underneath it. The OP's question was a pretty valid one…maybe I'm being altruistic & assuming the best of people, but I didn't take his question as a complaint that non-macro lenses suck or anything, but as a question wanting to learn how lenses are made. He wanted to know what separates a macro lens from the rest. That's not such a bad question, no reason to have so many negative posts from people trying to be clever. Hell, all those sarcastic questions people have been posting could be good topics to cover in this forum, I don't know the technical reasons behind a lot of the rhetorical questions y'all are asking.

What is the trade-off you gain by having a lens that doesn't focus quite as close? What physical limitation means it can only do one or the other?

Why can't all lenses open up to 1.4 or larger? What makes it so costly to open up that wide?

Why does a macro lens have to focus slower than others?

Why AREN'T all lenses 1" long? Or for that matter, why aren't they the size of their focal length? How does a 300mm focal length get built up from the various elements within the lens to make it 4" or 5" instead of 300mm?

Why does a digital camera produce noise?

Why does posting a question about how lenses differ in a photography forums beginner forum get a flood of sarcastic responses & only one or 2 real answers? Show some love people.

 

[jamesbjenkins]

I heard if you complete their survey upon exiting the store they'll give you a huge custom watermark to use too

Yeah, but the kicker is that the watermark only works on macro shots. Too bad all lenses can't do macro.

I see what you did there.

 

[Yucelphoto]

Why can't they put a 'pro' button on my camera so every shot I take is in focus, perfectly cropped, color balanced, non-grainy, and ready to print on a billboard 50'x30'?

Oh wait...they do. I just need to go to BestBuy to get a point-n-shoot. Silly me.

Pros can do that ???

 

[CMfromIL]

Why does posting a question about how lenses differ in a photography forums beginner forum get a flood of sarcastic responses & only one or 2 real answers? Show some love people.

Slow news day? No one BTW was directly attacking the OP. Just having a little fun musing about our own 'why don't...' questions.:greenpbl:

Why can't they put a 'pro' button on my camera so every shot I take is in focus, perfectly cropped, color balanced, non-grainy, and ready to print on a billboard 50'x30'?

Oh wait...they do. I just need to go to BestBuy to get a point-n-shoot. Silly me.

Pros can do that ???

No, Pros are not allowed to purchase those Point-n-shoot cameras. Only either retail customers OR a certified fauxtographer can get access to those type of cameras. Of course if you are planning to either shoot s wedding, birth of a child, or any other major life milestone you qualify for a 25% discount. They actually provide under certain circumstances a 50% discount, but in those cases you must sign a waiver that the event is within 5 days and you won't read the manual. But really...why would you need to?

 

[brush]

Why does posting a question about how lenses differ in a photography forums beginner forum get a flood of sarcastic responses & only one or 2 real answers? Show some love people.

Slow news day?

Fair 'nuff.

 

[Thunder_o_b]

The optics for a true macro (1;1 or greater mag) are different than for a reg lens. This is why you can't get the same quality from a "standard" lens with extension tubes even though it is 1:1 mag…I can't explain the tech though

 

[Heitz]

Brush, its ok. The snide remarks are pretty standard and expected. Anyway, comparing this question to 'why aren't all lenses 1.4' or the like isn't really valid because obviously, the physical components and sizes change. My question is why a standard lens wouldn't become a macro if you allowed a little extra throw on the focus. I mean, some macros make fine walk-around lenses, right, but the reverse is not true. I'm asking a technical question here not a silly one.

 

[Kolia]

The optics for a true macro (1;1 or greater mag) are different than for a reg lens. This is why you can't get the same quality from a "standard" lens with extension tubes even though it is 1:1 mag…I can't explain the tech though

My understanding is that a macro lens is designed to correct the fisheye effect you otherwise get when focusing at very close range.

Maintaining a decent depth of field is probably a design factor.

I don't know if these would translate into a unwanted effect at longer range tho.

 

[o hey tyler]

My question is why a standard lens wouldn't become a macro if you allowed a little extra throw on the focus.

Because obviously, the physical components and sizes change.

 

[pgriz]

Macros have much more travel at the close end of the focusing range than do "normal" lenses. This allows better focusing with very thin DOf that happens at close ranges. However, when used in "normal" situations, the travel is mostly at the far end of the forusing range, which is why some macros like the Tamron have a full/limit switch that either restricts the focusing range to the "normal" range, or allows full range.