The visual impact of perspective & sharpness control
By Avi Roth
Jewelry, as a photographic object is comparatively small in terms of three-dimensional extension. The range of movements offered by the view camera present great control over quality and visual presentation. This article about using a view camera in the studio-managed environment, discusses ways of deliberately influencing and modifying perspective and sharpness to attain
visual splendor and image quality.
Unlike SLR or medium format cameras (rigid body cameras), the view camera has capabilities for a full range of movements: rise and fall as well as tilt and shift of both front and rear standards. This is very important in digital jewelry photography since simply stopping down a modern digital lens all the way to f45 or f64 is a poor approach in obtaining sharpness and can have a damaging effect on image quality. Modern digital lenses perform optimally toward the middle of their aperture range: f/11 for short focal lengths, f/16 for moderate focal lengths, and f/22 for longer lenses. Sharpness has other implications on image quality as well: surface quality, data density, and separation of planes and edges.
In practical terms, when photographing a round pearl necklace or a pendant on a 180 object surface with a tilted camera plane of 30- 45, the view camera can quickly and easily be set to achieve sharpness throughout the entire object plane at the optimum aperture without stopping down, while retaining natural proportions. An SLR or medium format camera on the other hand, must always be stopped down to a maximum lens opening of f32 and beyond to achieve a greater depth of field, with all the associated disadvantages of image quality.
A limited amount of sharpness can be re-gained in post-production by image manipulation, but only with considerable losses in terms of image quality, and with unpleasing pixel distortions. For known reasons, diffraction has a large effect at high line frequencies, and to ensure that enough line pairs reach the digital sensor to achieve good sharpness, it is best to avoid very small apertures! This is why when desiring great image quality, its imperative to achieve sharpness by adjusted depth of field vs. stopping down the lens opening!
Another good example of the view camera advantage can be seen when photographing a square jewelry gift box. How do you photograph a square item from a dramatic angle without converging lines?
With a medium-format camera its not possible to compensate for converging lines at a small aperture like f/11 in order to get the entire subject sharp. Since lenses made for digital photography perform best in this aperture range a view camera like the Sinar p3, Arca, Linhof or Cambo would easily realize overall sharpness without loss of image quality while retaining the desired viewing angle.
The above examples demonstrate how the capabilities of a precision view camera with a full range of movements can achieve great overall sharpness at small apertures. But at the same time, the view camera also allows to create purposeful un-sharpness for artistic and creative interpretations. Utilizing the view cameras range of movements to manipulate perspective and sharpness will create spectacular special images of even ordinary jewelry objects - especially in close-up range.
In jewelry photography close-up sharpness over the entire subject, at the optimum aperture for best image quality, is inconceivable without camera movements. If you are searching for a system that will help you capture the ultimate digital image quality, I would highly recommend thinking about a view camera studio-solution. There are at least two other components beyond the camera platform you must consider: the digital back, and digital lenses. Its not inexpensive but the results will justify the investment.
By: AviRoth
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Avi Roth is an internationally recognized jewelry photographer and the founder of Digital Jeweller: Digital Jewelry Photography Solutions.For more jewelry photography tips and info go to www.jewelryphotographyonly.com
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