Примеры использования Focal lengths на Английском языке и их переводы на Русский язык
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The following fixed focal lengths/ fiels of view are available.
The same is true when shooting in the distance,at large focal lengths.
Microscopes, whose focal lengths are generally shorter, do not tend to suffer from this effect.
Provides a minimal magnification gain when used with focal lengths less than~80 mm.
The following focal lengths fi of the lens Li are nominal examples and will not affect the test results.
The zoom range is the ratio between the longest and shortest focal lengths.
Lenses(different focal lengths) and processing tables, in particular, have a substantial impact on the result.
Note how shift can rotate the plane of sharpest focus much more for shorter focal lengths.
Wide angle lenses have short focal lengths, while telephoto lenses have longer corresponding focal lengths.
This is often the most important consideration when choosing between macro lenses of different focal lengths.
However, another consideration is that shorter focal lengths often provide a more three-dimensional and immersive photograph.
The maximum aperture is perhaps the most important lens aperture specification,which is often listed on the box along with focal lengths.
The short eye relief is more critical in short focal lengths below about 10 mm, when viewing can become uncomfortable especially for people wearing glasses.
This distance is critical to maintain the proper depth of field through changing focal lengths and varying light conditions.
Other focal lengths may be used, for example, if a wider beam is desired or a smaller image of the sample is to be formed on the receptor.
And of course, if you have a zoom lens,try taking pictures at different focal lengths to check the flashlight zoom, if it has any.
Telescopes with long focal lengths often have a“blind spot” when pointing near the zenith, because the eyepiece-end of the optical tube bumps into the mount's legs.
The fact is that the optics on a DSLR camera has a volume, andnoticeable effect of the background blur(bokeh) appears even at medium focal lengths 35-50mm and more.
However, with lens coatings at low powers(focal lengths of 20 mm and up) they are acceptable, and at 40 mm they can be excellent.
On the other hand, this also means that the perspective will be more strongly influenced for shorter focal lengths, which may be an important consideration.
The following table provides an overview of what focal lengths are required to be considered a wide angle or telephoto lens, in addition to their typical uses.
The definition of ultra-wide is a little fuzzier, butmost agree that this realm begins with focal lengths somewhere around 20-24 mm and less.
Using this formula for macro lenses with much longer focal lengths, such as 105 mm or 180 mm, will tend to slightly underestimate the the effective lens f-stop.
It is known that the principle of action of such a multimodule camera will be based on the creation of a high-quality photograph by applying images with differing focal lengths.
Varied focal lengths and lenses were employed to differ from the habitual portrayal of Africa in documentaries-which employ telephoto lenses to shoot the wildlife from a distance.
However, this is clearly inadequate for the purposes of carefully arranged photography using SLR orrangefinder cameras, where high apertures and longer focal lengths are the norm.
Please note that focal lengths listed are just rough ranges, and actual uses may vary considerably; many use telephoto lenses in distant landscapes to compress perspective, for example.
Larger sensors can get away with larger circles of confusion because these images do not have tobe enlarged as much, however they also require longer focal lengths to achieve the same field of view.
In fact, it is very difficult to see sharpness at short focal lengths- when you rotate the focus ring, the image in the viewfinder remains practically unchanged, although there is still a small change clearly visible on a large screen monitor.
The top-quality focusing mechanism moves smoothly without backlash,optimally supporting the photographer's creative interplay with the focal plane of high-speed fixed focal lengths.