New answers tagged macro
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Tables an charts base the circle of confusion, the Case A 50mm lens focused @ 2 feet aperture f/8 circle of confusion 1/1000 of focal length = 0.05mm. Span of D of F = 0.39 feet.
Case B 100mm lens focused @ 4 feet aperture f/8 circle of confusion same 0.05. Span of D of F same 0.39 feet = 4.7 inches
Case C 100mm lens focused 4 feet criteria for D of F on1/...
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Here is the standard Depth of Field formula for reference:
DOF = 2 u2 N C / f2
N = aperture F-number
C = circle of confusion
u = distance to subject
f = focal length
When aperture and subject size within the frame are constant, DOF will not change because changes to focal length (f) and distance (u) will be proportional to each other and ...
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For your needs, you don't need to go terribly overboard since you're looking for texture, not aesthetic image quality(unless i misunderstood you)
Here i took a shot just for you, using an old t3i, tamron 16-300@300, plus 68mm of inexpensive extension tubes, and an on camera speedlight with a big bounce card. cropped to 10mp. the opal i measured with a ...
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Any modern camera will have more than enough pixels to meet your needs, especially if we’re just talking about web viewing. Take this image for example (my apologies on it being a screengrab from my phone. The OG is over the size limit and I’m unable to mess with it at this time):
That was shot with a 5Dmk2 at 21 megapixels. For my use cases, I go with a ...
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It's all basically a trade-off between sensors size and image quality. Large sensor sizes give a better image but are harder to work with.
If you want an 8mm bead to fill the frame, then on a DSLR you need a 3X magnification (full-frame) or 2x magnification (APS-C) because the sensor eight are respectively 24mm and 16mm. This is even worse for the 4mm beads:...
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Normally a large object in front of the lens projects a small image behind it, onto the sensor. When you flip the lens, a "small" object "behind" the lens projects a "large" image in "front" onto the sensor. Basically, the magnification ratio is flipped. (I haven't done the math, so it may not be exactly like that.)
The max extension I can get with tubes is ...
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The reason for inverting the lens --- The typical camera lens is optimized to image a world where objects are spaced at different distances and to project this image on the flat surface of film or digital image sensor. Thus the rear of lens is optimized to work a flat surface. When doing macro work, most times the object being imaged is quite shallow or ...
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NO. Manual focus will NOT be available with a Canon EF 50mm f/1.4 that is reverse mounted to the camera body.
Reverse mounting attaches the filter threads, and all the glass elements of the lens, directly to the camera body. When you turn the focus ring the body of the lens will move back and forth but it will not move the glass elements.
The only way to ...
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For Nikon F-mount lenses with mechanical aperture control, you can use the Nikon BR-6 Auto Diaphragm Ring.
For Canon EF lenses, which have electronic only camera/lens communication, you can use an "Automatic" Macro reverse mount adapter.
There are also other "DIY" ways to set the aperture to a desired setting.
For Nikon F-mount lenses they usually involve ...
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In practice, aside from the potentially "strange" appearance, there's unlikely to be a significant difference between placing an extension tube between the body and adapter or between the adapter and lens. However, there are a few potential differences:
The way light reflects and scatters inside the adapter and tube would be different. One setup might ...
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You don't really say, but it seems you have an EF lens and an EOS M camera?
They have different diameters, so does it make any difference if I put it between lens and adapter or between adapter and camera?
You can do either.
You can use EF-M extension tubes with the smaller diameter mount between the camera and the adapter.
You can use EF extension ...
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