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ving
22-08-2007, 12:15 PM
anyone here done a lens reversal macro shot?

well i tried it with my pentax 50mm f1.4. with lens hood on i just reverse the lens on teh camera and held it in place with 2 rubber bands :D

the pictures show are of a little mantis i found indoors. the lighting is poor so the exposure is long (hence the noise)

first pic: full frame reduced for the web
second pic: 800x600 crop of full frame (ie 100% size crop) this is wher noise shows the most
third pic: a 50% crop of another pic resized for the web.

it was quite an interesting experiment and i think a deeper dof would have helped. alas the lighting wouldnt have handled it.

any comments or questions welcome :)

Terry B
22-08-2007, 12:49 PM
Interesting effect. There is very little depth of field at these mags. Even stopped down to f22. You need bright lights, tripod and long exposures.
I have recently bought a lens for the opposite effect- a fisheye 30mm(for medium format). I tried a photo of a dafodil at about 20cm distance that only takes up the middle third of the frame. I will post them when they are developed-(yes, stil using film:eyepop:)

ving
22-08-2007, 01:05 PM
having never used a macro lens before i wonder if a standard macro lens has the same dof problems...

rogerg
22-08-2007, 01:39 PM
Neat experiment :thumbsup:

I do all my macro work (lots of it too) using extension rings, usually together with my 70-200 F4/L. My partner does the same with her 28-135. DOF is a normal problem with macro from our experiences & reading, whatever the lens combination. Every single shot is a careful balance between desired DOF, required exposure time and brightness.

I'm lucky that with digital I can just bump the ISO up to 800 if I need to, she gets stuck with the 100 speed Velvia she has in the camera :P

I haven't tried reversing a lens, but have read about it, it would be interesting to try! What I would be more interested in trying is a 100mm dedicated macro lens. I have always wondered what the difference in DOF and image quality is between that and using extension rings.

Roger.

rogerg
22-08-2007, 01:42 PM
Oh, and of course the DOF issue is worse the longer the lens. 28mm isn't so bad, 200mm is much worse. Just like normal non-macro photography. So sometimes I zoom out rather than changing F stop.

ving
22-08-2007, 01:50 PM
if you find out roger tell me :)