![]() Stopping the lens down to the smaller apertures – f/16 to f/32 - creates many problems that are easily avoided by using more intermediate apertures such as f/8 or f/11. Although photographer opinions vary, I feel that f/32 and even f/22 is worthless on this lens and probably most other lenses as well. Although, in theory, the depth of field is greater at f/32, the overall image sharpness is far less than f/11 due to diffraction. I was horrified by how bad it is at f/32-even f/22 produced underwhelming results. When I tested the diffraction on my Canon 180mm macro lens for a new book-Close Up Photography in Nature. This bending is known as diffraction and causes a loss of sharpness everywhere in the image. Due to the wave nature of light, as the hole it passes through decreases in diameter, a larger percentage of the light touches the edge of the hole and bends. In simple terms, these f/stops refer to the tiny hole in the lens that is called the aperture. Due to the laws of physics, though, the greatest depth of field is always at the smallest aperture (largest f/stop number) which is usually f/22 or f/32. With a 200mm f/4 lens, for example, the sharpest apertures are around f/8 to f/11. The sharpest aperture on the lens is typically two to three stops down from the maximum aperture on the lens. ![]() Probably, wouldn't be useful on anything shorter than an 85.All photographers have problems achieving sufficient depth of field and superb image sharpness imultaneously because it is a trade-off. Understand it's a motorized extension ring, so your focal range will come in. I've used for handheld and on a test shot of a marigold processed with first attempt with Helicon Focus got a result that passed muster and delighted as long as you didn't pixel peep. If a lens isn't on the list that doesn't mean it doesn't work with it, they just tested the common ones and look to the community to verify more. The list is short but appears to include the common lens used for macro. They have a list of lenses that have been verified. It doesn't work with all autofocus lenses. It only works with auto focus lenses and you put the camera in manual mode. You set a start focal point and a number of "steps" it should take to get to either infinity or max near focus (you choose which direction you want to go.) Each "step" is a shot. FB Tube rotates your focus ring same as your camera would with the newer top end cameras. the memory ain't what it used to be!) A mechanical device such as this can be used with virtually any camera and lens (and lens accessory, such as macro extension tubes), including manual focus.įB Tube isn't a rail so that metric doesn't apply. But, it also might have been made and sold by a different company (gettin' old. That could be programmed with image count and focus intervals for various focus stacking needs. If I recall correctly, HeliconSoft (the company that offers all the above) at one time offered a motorized, computer-controlled focusing rail device for use on a tripod. Check the HeliconSoft website for compatibility and/or contact them for recommendations. Which you would need depends upon the camera and lens you're using. Remote is software, while FB Tube is hardware and software. Helicon Remote and Helicon FB Tube essentially do the same thing. This device also requires a lens with autofocus capabilities. It is currently available only in Canon EF mount and Nikon F mount (both DSLR lens mounting systems, which might be possible to adapt to some mirrorless camera systems). ![]() The device is controlled by computer, tablet or smart phone. "Helicon FB Tube" is a physical device that's fitted between lens and camera both to allow the lens to focus closer and to provide incremental focus bracketing. This version is in development to be a future version of Helicon Remote. "Helicon Remote Beta" is same as Helicon Remote with a few newer camera models added (including some Sony, Canon and Nikon mirrorless), although in some cases there may be limited functionality. The software resides on a computer or other device, to which the camera will be tethered. "Helicon Remote" is a software that can be used to control select Canon and Nikon DSLRs and will make the cameras do focus bracketing as described above. Before buying any of the following, check your camera's capabilities in this regard. Some cameras now have built in ability to do focus bracketing, where the camera shifts focus slightly for a series of shots that will be later post-processed with the above software. "Helicon Focus" is a computer image editing software used to combine a series of images taken at different focus points into a single image with greater depth of field than is possible optically. Looks interesting but does it really work? ![]() Has anyone used the Helicon Focus? It is used for automatic focus stacking via a lens attachment combined with their software program.
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