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11/18/2004 01:14:03 PM · #26 |
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11/18/2004 02:24:36 PM · #27 |
Here's how your figure out magnification on reversed lenses:
Divide the focal length of the main lens (on the body) by the focal length of the lens being reversed. When I reverse my Olympus 50mm F1.8 in front of my 105mm Macro lens, I get a magnification of 2.1:1. So, in theory you should get a 1:1 magnification by reversing a 50mm lens in front of another 50mm lens.
If you reverse your 50mm in front of your 70-200mm @ 200mm, you should get a magnification of 4:1.
Keep in mind that the working distance between the lens and subject will be 1 or 2 inches and you will need a lot of light because you'll need to shoot at small apertures (high F value) to get any kind of workable depth of field. This is best done by using an off-camera flash or outside on a bright sunny day.
The problem with using a standard lens is that a a maximum aperture of 3.5 or 5.6 will cause a lot of vignetting. You're better off using your 1.8 lens.
Originally posted by tyrkinn:
Do you have to have a standard lens reversed on a telephoto lens? Or could I reverse an old Olympus 50mm f/1.8 on my Canon 50mm f/1.8 with decent results? (The canon has a 52mm thread and the olympus has a 49mm thread, coupler ring on B&H for 8 bux)
I also have the canon 18-55 kit lens and 70-200 f/4 L lens, but the thread on thad one is much larger (67mm) |
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11/18/2004 02:35:55 PM · #28 |
Originally posted by Jacko:
Here's how your figure out magnification on reversed lenses:
Divide the focal length of the main lens (on the body) by the focal length of the lens being reversed. When I reverse my Olympus 50mm F1.8 in front of my 105mm Macro lens, I get a magnification of 2.1:1. So, in theory you should get a 1:1 magnification by reversing a 50mm lens in front of another 50mm lens.
If you reverse your 50mm in front of your 70-200mm @ 200mm, you should get a magnification of 4:1.
Keep in mind that the working distance between the lens and subject will be 1 or 2 inches and you will need a lot of light because you'll need to shoot at small apertures (high F value) to get any kind of workable depth of field. This is best done by using an off-camera flash or outside on a bright sunny day.
The problem with using a standard lens is that a a maximum aperture of 3.5 or 5.6 will cause a lot of vignetting. You're better off using your 1.8 lens.
Originally posted by tyrkinn:
Do you have to have a standard lens reversed on a telephoto lens? Or could I reverse an old Olympus 50mm f/1.8 on my Canon 50mm f/1.8 with decent results? (The canon has a 52mm thread and the olympus has a 49mm thread, coupler ring on B&H for 8 bux)
I also have the canon 18-55 kit lens and 70-200 f/4 L lens, but the thread on thad one is much larger (67mm) |
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hey Jacko,
how about writing a tutorial on macro photography?
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11/18/2004 03:25:53 PM · #29 |
lol seems like somebody bumped my multi-month old thread.
Message edited by author 2004-11-18 20:26:08. |
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11/18/2004 10:46:36 PM · #30 |
| If I go ahead with the 50 on 50 f/1.8 setup, whad does the 1:1 magnification really mean? Can anybody show me exsamples of shots done at 1:1 with a similar setup? |
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11/19/2004 03:26:50 AM · #31 |
Originally posted by tyrkinn:
If I go ahead with the 50 on 50 f/1.8 setup, whad does the 1:1 magnification really mean? Can anybody show me exsamples of shots done at 1:1 with a similar setup? |
1:1 means (if I understand this correctly) that 1 cm in front of the lens is 1 cm on the sensor or in other words, the image itself has 1:1 correspondence to the object.
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