Lens Flair

This pic wouldnt have been taken if not for Ice

50mm_by_lokkydesigns.jpg
 
IceBone said:
Hey, BCS: what are bellows good for? Never really understood them. o_O
Click to expand...

They act like a combination of a variable-length extension tube (48-208mm) and a focusing rack. At those kind of extensions and subject proximity, focusing is done primarily by moving the camera/bellows assembly back and forth.

The ultimate goal of a bellows system is to produce really, really large magnification. A normal dedicated macro lens, like a Micro-Nikkor (not those zooms that say "macro" on them as a sales feature), will have a maximum reproduction ratio of 1:1. This means that a subject of size X will be projected at that very same size X onto the film/sensor.

Just to give you an idea of what a bellows can do, I reverse-mounted my 50mm onto the bellows and look a photo of my monitor. (The example pic on the other page was with a different lens that didn't work as well.) I have a 22" monitor at a resolution of 1680X1050 pixels. Vertically, it's 295mm, so each pixel is 0.28mm tall.

Now, with that reversed 50mm (which isn't really suited for the task, by the way), I can take a picture that has 14 monitor-pixels vertically in the photo. Since my camera's sensor is 15.5mm high, that means the the pixels are projected at 1.1 mm tall on the sensor. Dividing the two sizes, we find that's a reproduction ratio of approx. 4:1, four times that of a normal macro lens.

Now, with the right combination of the bellows and Nikon lenses, I should be able to get a reproduction ratio of 11:1. I've gone one step further and ordered a couple of lenses designed for enlarging microfilm, one with a theoretical rep. ratio of 14.5:1 and the other with a theoretical rep. ratio of 31.5:1, which is intense. Whether it'll work out I have no idea yet, but they cost me a grand total of $17.50 shipped so I figure it's worth a try.

Well, that's the basics of photomacrotography, I'm really just getting things figured out as well.


Edit: Hey, 4,000 posts, whaddaya know.
 
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:yucky::idiot:

@ BCS: Thanks for the explanation. If I understand this correctly, the bellows is just for putting distance between the lens and the sensor in a closed environment. And how you can tilt the lens at the front... is that how they do that effect in Heroes, where the subject in the foreground AND the background are focused and everything else is blurred out? I've noticed it a few times during their "intense" dialogues.
 
Ice, you are getting one hell of a sweet lens. It's even better than the one I had gotten used to.

AF_Nikkor_by_lokkydesigns.jpg
 
A late christmas decoration :santa:

https://pic.armedcats.net/2008/01/12/hjerte.jpg
 
https://pic.armedcats.net/2008/01/12/mx5yo.jpg
 
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