The preset aperture mechanism — a click-stopped ring to set the stop-down aperture accompanied by a stopless ring that smoothly moves between wide open and the aperture preset on the other ring — has several advantages for digital cameras:
– Digital cameras generally can’t automatically stop-down a manual lens when you press the shutter button, so they behave exactly like the film bodies that were expected to be behind preset lenses.
– I’ll often preset the aperture at the smallest aperture that will not degrade the image quality by diffraction or sharply-imaging dust, then just use the stopless ring to vary within the acceptable range.
– The stopless ring allows changing the aperture during videos without steps or click noises.
Test with the pop up flash on D750. Lens probably the 24-120. Or the 50? Have to found the originals.
Interesting…had forgot all about this. Need to try it properly.
High speed sync – KEVIN KUBOTA “I’m usually choosing f/4 as my smallest aperture,” he says, “and I generally I prefer f/2.8, 1.8 or 1.4. Shooting outdoors at those apertures, I almost always have to be shooting high speed sync to get a fast enough shutter speed to prevent overexposure.”
Kevin selects large apertures to insure shallow depth of field, which in turn creates soft backgrounds, eliminates distractions and focuses the viewer’s attention on the subject. A soft background is a pro touch, and if often takes a high shutter speed and high speed sync to make it happen.
Another reason for high speed sync outdoors is to darken the sky for mood, or to darken the background in order to hide location distractions or details.
High speed sync can come into play for indoor images, too. Faced with a brightly lit room, or one in which you’re bouncing your flash off a white ceiling, you’ll need to boost the shutter speed to prevent overexposure. More likely, though, you’ll find yourself in a room with a big picture window or an expanse of glass through which sunlight pours. In that case, expose for the outside so the window area doesn’t blow out, then use high speed sync to effectively balance the outside illumination.”
How It Works In high speed sync mode the flash is not fired in one burst of light; it’s emits a series of pulses, an incredibly rapid series that illuminates the scene as the camera’s focal plane shutter moves across the sensor. This strobing action takes an enormous amount of flash power, and the flash essentially divides up the amount of light into segments as the shutter travels. The faster the shutter speed, the less flash power is available. Often the reduction in power does not noticeably affect the image, but when it does, photographers often compensate by either moving closer to their subjects or using more than one Speedlight.
» Find and Use Hyperfocal Distance for Sharp Backgrounds
The preset aperture mechanism — a click-stopped ring to set the stop-down aperture accompanied by a stopless ring that smoothly moves between wide open and the aperture preset on the other ring — has several advantages for digital cameras:
