The Crayford telescope focuser design – developed in 1971 by John Wall and named after the Crayford Manor House astronomical society – has a number of important advantages over rack-and pinion and can be home built out of wood by almost anybody with a bit of patience and the right tools at hand. I designed this focuser specifically to carry the weight of a Nikon D7100 camera on prime focus (± 800 gr), which is considerably heavier than even the largest eyepieces. So far, it is holding up admirably.
The Nikon F-Mount was launched with the Nikon F camera in 1959 and has remained virtually unchanged since, making it the only lens mount still in production over 5 decades after its introduction. The camera mount comes essentially in 3 flavors: F, AI-S and AF, with some minor adaptations for particular cameras, mostly the digital entry-level models, which feature 2 extra screws and the minimum aperture confirmation notch, discussed later on.
On November 25 last, Tamron announced the launch of the successor of its very respectable 200-500mm f/5-6.3 ultra tele-zoom, the Di SP 150-600mm F/5-6.3 VC USD, the first afficionado super tle at under $1500 On November 25 last, Tamron announced the launch of the succesor of it's very respectable 200-500mm f/5-6.3 ultra tele-zoom (test here), the Di SP 150-600mm F/5-6.3 VC USD. What does that letter-soup stand for, you wonder? Di means “Digi…
Nikon USA anounced an instant savings offer for a D5000 "Outfit", which includes the AF-S DX 18-55 f/3.5-5.6G VR and the AF-S DX 55-200 f/4-5.6G VR lenses, which can now be had just 5 cts. short of U$ 1.000.
Review of the ASP 18-200mm f/3.5-6.3D IF DC Sigma: You can’t have at All.Strengths, weaknesses, competition and pro reviews. In spite of its optical flaws, still quite respectable for an extreme zoom at this price point.
Review of the APO 100-300mm f/4D EX DG HSM Sigma: Sharp, even at f/4, excellent construction, great value for money.
Review of the ATX Pro 12-24 mm f/4G Tokina. Strengths and weaknesses, links to pro reviews. Conclusión: big bang for your buck.