Which Macro lens?
Discussion
simpo two said:
'Lifesize' means 'Lifesize on the sensor'. Obviously you can blow up an image as big as you like, but that's nothing to do with the lens.
Another example: you don't need a bigger camera to make a 10"x8" print!!!
I know on the latter part
I'd be walking round with a camera the size of a van if it didn't work that way I can get my head round the focal length thing and what that typically means you'll get on the frame.
Just find it odd that the manufacturers talk in magnifications for macros, where they studiously ignore it on all their other lenses...
murph7355 said:
Just find it odd that the manufacturers talk in magnifications for macros, where they studiously ignore it on all their other lenses...
Interesting point. I know that the optics for macro lenses get very complicated; they're not like normal lenses.
But think of this: if 1:1 means lifesize on the sensor, imagine going out on a walk. You see a church on a hilltop, strap on your 500mm telephoto and get the church to fill the frame. Wow, what magnification, you think! But hang on, is the image of the church lifesize on your sensor? No, it's about 2cm high, not 50m. So where's the magnification in that?
Hopefully somebody cleverer than me can step in and explain this in simple terms...?
V6GTO said:The 180mm is 1:1 though, and the distances quoted (at least for the 100mm) are for subject to film plane (or digital sensor), not the end of the lens.
The 100mm f2.8 manages 1:1 at about 310mm from lens to subject. The 180mm f3.5 goes to 1:2!, and at a distance of 480mm between lens and subject. The 100mm is £339 and the 180mm (which is an L lens, remember) costs £829.
Martin.
simpo two said:Click here
Interesting point. I know that the optics for macro lenses get very complicated; they're not like normal lenses.
But think of this: if 1:1 means lifesize on the sensor, imagine going out on a walk. You see a church on a hilltop, strap on your 500mm telephoto and get the church to fill the frame. Wow, what magnification, you think! But hang on, is the image of the church lifesize on your sensor? No, it's about 2cm high, not 50m. So where's the magnification in that?
Hopefully somebody cleverer than me can step in and explain this in simple terms...?
article said:
What you want is a macro lens. Fortunately, it is difficult to buy a bad macro lens. This is kind of odd in a world where 90% of the lenses sold are bad. Here's my theory: Every day at least one man wakes up and says to himself "I have a 1.5 inch long penis; I think I will buy a big SLR like a pro. But I don't want to spend money on frills like lenses so I'll get a Tokina zoom." However, no man ever wakes up and says to himself "I have a 1.5 inch long penis. I think I will buy a macro lens so that I can make a 1:1 photograph of my penis and distribute this photo from my Web server. But I don't want to spend too much on this lens so I'll try to find a cheap Sigma."
In short, anyone in the market for a macro lens is already fairly sophisticated and quality conscious. If you read USENET then you know that the world is full of people asking "is this $150 Tamron 75-300 zoom as good as a $900 Nikon 300 prime?" Can you blame Tamron/Tokina/Sigma for trying to separate people like this from their $150? But there isn't apparently a big enough collection of fools in the market for macro lenses to support a junky macro lens subcategory.
V6GTO said:
Tommorrow I'm going to spend all day with the 100-400 and a set of extention tubes to see if one really needs to part with serious wedge to get close.
Don't hassle me for result too quickly though coz I've got a stinking cold that Debbie brought back from England.
Martin.
Sounds interesting, I look forward to seing what you find out. I would have thought that using that lens for macro stuff will be very tricky because the long focal lenghts wil mean a lot of lens shake, and framing up precisely will be difficult, even with a tripod. Good luck!
simpo two said:
Ah yes, gone are the days when you could simply turn your 50mm standard lens round and get an f1.8 1:1 macro for the price of a reversing ring...
Jumpers for goalposts... :wistful:
I was like a dog with two tails for a week when my Brother-in-law told me about that trick. My Canon T90 got a pasting that week!
Martin.
simpo two said:
Ah yes, gone are the days when you could simply turn your 50mm standard lens round and get an f1.8 1:1 macro for the price of a reversing ring...
Jumpers for goalposts... :wistful:
i've done that with my d1x! only once though, seems like asking for trouble if you want to keep a clean sensor
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