There is no communication between lens and camera (except in the case of the one version of the Canon adaptor). Since the lenses are, with the exception of the 110mm, not particularly light this firmness is actually somewhat reassuring. This focus movement displaces the lens up to 46mm from the closed position (beyond infinity) to the point of nearest focus. This moves smoothly if more stiffly than a standard DSLR focus ring. The main body of the adaptor is the helicoid focus ring (there is no focus mechanism in the lens – though see 50mm and 140mm lens descriptions below) which replaces the bellows focus rail of the RZ67 camera system. The levers used to set the leaf shutter in the lens slot nicely into appropriate holes in the outer ring of the adaptor which then twists to open (and close for storage) the leaf shutter ready for use with the DSLR. The RZ67 lenses fit into the adaptor (as they do on the RZ67 camera) by mounting in the correct orientation and then locking them into place by twisting a locking ring on the lens (about 30°) rather than by twisting the lens itself, as on a DSLR system. Whilst this is on the whole not a problem it does affect the shortest focus distances of each lens which is about double that which it would be on the RZ67 camera (see below). The registration distance for Pentax lenses is slightly longer than that for Sigma (45,5mm vs 44mm) so that the adaptor can focus ‘beyond’ infinity. (also showing the metal spacer under the camera body) SD1M and adaptor mounted both attached to tripod head with 140mm lens / extended helicoid Whilst this does not look quite so ‘pretty’ (see image above) it is very effective. The Pentax mount is narrower than the Sigma Bayonet so that, if not centred, it is possible that some light may enter the camera – I have corrected this by adding several layers of insulation tape around the end of the adaptor. However, since the bayonet is not absolutely identical there is a small amount of residual rotational movement as well as a small amount of lateral movement in the plane of the mount that is possible even after the adaptor is locked in place. Since the Sigma SA Mount is closely related to the Pentax-K mount, it is not surprising, though not so well documented, to find that the Pentax-K bayonet fits reasonably well into a Sigma SA mount. Several versions of this adaptor are available for Nikon-F, Canon-EF (with ( see here ) and without focus confirmation via a dandelion chip), Pentax-K ( see here ) and Sony Alpha Cameras. The essential piece of equipment which allows the use of these lenses. The showing metal peg on the adapter which opens the lens shutter ready for use. I am extremely happy with the way these lenses have performed to date and my aim is to show how the lenses stand up to the Foveon APC Merrill Sensor in the form of the Sigma SD1M which has the ability to capture very high levels of detail due to the lack of interpolation of the data. A simple search of eBay or KEH Camera ( see here ) will give a good indication of the extremely favourable prices with which these lenses can be acquired (though it is important to note whether the lens represents the latest iteration of a particular focal length). As such, although both camera and lens production have been discontinued, there is an extensive 2 nd hand market. The Mamiya RZ67 camera system was extremely popular amongst studio film photographers for many years with both camera and lens going through several generations. Technical data of all the lenses available under the section: Lenses and AccessoriesĪ good summary (for film) of available lenses (including the various lens iterations) At the time I was looking into acquiring the lenses it was very clear that most, if not all, the reviews of the RZ lenses that could be found on the internet were based on working with film, I thought that having subsequently acquired a few of the lenses, that I would take the time to write an article in the event that anybody else might be interested in exploiting these lenses on a DSLR system. Nor is it meant to be a comparison with any existing DSLR lens. of the RZ67 lenses (that I own) when used with a DSLR camera. Astro-Photography with the SIGMA fp (2)įirst of all let me start by saying that this is not meant to be an all encompassing review with resolution charts, etc.Coppers (Lycaena) / Browns (Aricia) / Hairstreaks (Theclinae).Blues (Polyommatinae / Pseudophilotes / Phengaris / Cyaniris).
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