Personal computing discussed
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continuum wrote:Using a macro lens to shoot landscapes should be fine.
Also note that due to the close-focus ability, often there's quite a bit more travel in the focusing elements-- so focusing may be slower than non-macro designs with more limited focusing ranges.
Finally note that some macro lenses, despite the designation, aren't really macro lenses-- a true macro lens is generally advertised with its actual magnification (usually 1:1 or in some cases 2:1), as opposed to many regular lenses with a "macro" label applied that are not capable of 1:1 magnification or similar.
Airmantharp wrote:What does this differ from my understanding that what you frame on the viewfinder hits the entire area of the sensor(full frame lens on full frame body)?A 'true' Macro lens focuses down to 1:1, which means that the subject is projected onto the sensor at the same size that it is in real life.
What excatly do these "1:1", "1:0.25", etc mean?Also, if a true macro lenses is 1:1.0, or '1.0' magnification, many zoom lenses offer 'macro capability' that ranges from say 1:3 to 1:4, or .33 to .25 magnification.
I have AF-S Nikkor 50mm f/1.4G. What is the magnification ratio of this lens?Note that there a number of dedicated 'macro lenses that offer 1:2 or .5 magnification from various manufacturers. Many 50mm macro lenses are like this, while most 100mm macro lenses offer full 1:1 magnification.
I have Nikon 50mm f/2.8F and 24-120mm f/4G. I like to shoot close-up views of flowers. I can do this using the 24-120mm if the flower is not a tiny one.What exactly are you trying to capture with a macro lens?
PenGun wrote:The 1:1 is just that the image will be life size on the sensor, at 1:2 it will be half size.
churin wrote:PenGun wrote:The 1:1 is just that the image will be life size on the sensor, at 1:2 it will be half size.
What does "life size on the sensor" mean? Does 1:0.25 mean x4 size? If so, four times of what?
PenGun wrote:churin wrote:PenGun wrote:The 1:1 is just that the image will be life size on the sensor, at 1:2 it will be half size.
What does "life size on the sensor" mean? Does 1:0.25 mean x4 size? If so, four times of what?
Ummm ... a nickel will be nickel size on the sensor at 1:1, half size on the sensor at 1:2 and so on.
churin wrote:PenGun wrote:churin wrote:What does "life size on the sensor" mean? Does 1:0.25 mean x4 size? If so, four times of what?
Ummm ... a nickel will be nickel size on the sensor at 1:1, half size on the sensor at 1:2 and so on.
An image of a nickle can be life size on the sensor but how about that of an elephant? I am asking this to possibly provide a clue why I fail to understand your explanation.
churin wrote:I have AF-S Nikkor 50mm f/1.4G. What is the magnification ratio of this lens?
Yeats wrote:churin wrote:I have AF-S Nikkor 50mm f/1.4G. What is the magnification ratio of this lens?
About 1:7. See here: http://www.bhphotovideo.com/c/product/5 ... _1_4G.html
An aspect of dedicated macro lenses that many folks find appealing is that they are flat-field - that is, there is little field curvature, so the edges of the lens are nearly as sharp as the center.
Voldenuit wrote:Caveat: Not all macro lenses are flat field. The ones that are tend to be for document copying, and tend to be 35 or 50 mm lenses that often top out at 1:2. I'd also say that being flat field conveys little benefit when shooting conventional macro subjects like flowers and insects, which are 3-dimensional and often not filmed co-planar with the sensor. Lastly, a lens can have field curvature and still have sharp corners, it just means that planar subjects will have the frame edges out of the plane of focus (but often still within the zone of confusion).
continuum wrote:Flat field, aka planar, means the plane of focus is flat.
e.g. focus on a brick wall with the lens perfectly perpendicular to the brick wall, and the entire brick wall will be in focus.
Many lenses do not actually have a flat plane of focus-- instead it is curved-- so in the situation as described above, the focused point used (say the center focus point) will result in the center of the brick wall being in focus and the edges of the wall being out of focus, due to the curved plane of focus of the lens.
Caveat, of course, is that if you are shooting with sufficient depth of field, the whole brick wall may remain in focus despite the curved plane of focus...
JustAnEngineer wrote:Because they have a very wide range of focus (from infinite distance down to just a few inches in front of the lens), true macro lenses may be slightly slower to focus than non-macro lenses. Many of them will include a focus range limit switch to eliminate this drawback when the lens is used for non-macro photography.