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Astrophotography Lenses

The high resolution of digital sensors provide quite a challenge for normal photographic lenses. These lenses were made for general daytime photography. Shooting pinpoint light sources across a wide field if stars is the most difficult test possible for a camera lens.

Telescopes are corrected to give their best performance at relatively slow focal ratios at infinity. Camera lenses must cover comparatively large fields at various subject distances at much faster focal ratios. So it is not really fair to compare the performance of a camera lens to an astronomical telescope, especially when the camera lens is used wide open.

Rokinon 16mm f/2.0

The Rokinon 16mm f/2.0 ED AS UMC CS Lens is an exciting new wide-angle lens that is designed specifically for APS-C sized DSLR cameras. This lens has 2 aspherical elements and one extra-low dispersion ED element that give it outstanding optical performance, even when used wide-open. It should be of particular interest to photographers who want to shoot meteors, constellations, the Milky Way, and time-lapse starscapes.

Aperture  
Aperture Range – Wide / Longf/2-22
Number of Aperture Blades8
Rounded Aperture?
 
Weight  
Manufacturer Specification Weight20.6 oz  (583g)
Actual Weight17.3 oz  (490g)
Lens Hood Weight0.9 oz  (25g)
In-Use Weight18.2 oz  (515g)
 
Size  
Manufacturer Spec Size (DxL)3.39 x 3.52”  (86 x 89.4mm)
Measured Size (DxL)3.26 x 3.74”  (83 x 95.1mm)
Max Length at Full Extension3.74”  (95.1mm)
Internal Focusing? / Extends with Focusing?Y / N
Lens Hood Size (DxL)3.93 x 1.95”  (99.7 x 49.5mm)
Lens Length with Hood (Min-Max)5.5 – 5.5”  (139.7 – 139.7mm)
Size of Rings: Focus / Zoom1.64”  (41.7mm)
Filter Size77mm 
Front Element (Filter Mount) RotatesN
 
Focus  
AF Motor Type
Full Time Manual Focus
Focus Ring Rotation152°
Focus Limiter? / Focus Limiter Ranges
Distance Scale? / TypeY / Engraved
 
Close Focus  
Specified Min Focus Distance7.87”  (200mm)
Tested Min Focus Distance (Wide / Long)7.8”  (198mm)
Maximum Magnification (MM)
 
Features  
Lens Hood Included / Model?Y /
Weather Sealed? / Filter Required?N
Image Stabilization? / Stops? / Tripod Sensing?N
Extender Compatible?N
Case Included? / Type?Y / Soft Pouch 
47.25″ x 31.5″ Subject Framing DistanceOn APS-C DSLR:
16mm = 3.16′
1200mm x 800mm Subject Framing DistanceOn APS-C DSLR:
16mm = 964mm

Sigma 35mm f/1.4

This is an in-depth review of the Sigma 35mm f/1.4 DG HSM Art prime lens that was announced at one of the largest photo shows in the industry, at Photokina in Germany on September 17, 2012 for Sigma, Canon, Nikon, Pentax and Sony mounts. The announcement came on the same day with Sigma’s new restructuring of its lens lineup, with three new categories that would differentiate different types of lenses: “Contemporary” for small and lightweight consumer lenses, “Art” for professional zoom and prime lenses and “Sports” for long lenses targeted at sport and wildlife photography. Being a professional-level lens targeted at a variety of photography needs, including portraiture, landscapes and travel, the 35mm f/1.4 is the first Sigma lens that falls into the “Art” category.

Aperture  
Aperture Range – Wide / Longf/1.4-16
Number of Aperture Blades9
Rounded Aperture?Y
 
Weight  
Manufacturer Specification Weight23.5 oz  (665g)
Actual Weight23.5 oz  (665g)
Lens Hood Weight1.1 oz  (30g)
In-Use Weight24.5 oz  (695g)
 
Size  
Manufacturer Spec Size (DxL)3.03 x 3.7”  (77 x 94mm)
Measured Size (DxL)3.07 x 4”  (78 x 101.7mm)
Max Length at Full Extension4”  (101.7mm)
Internal Focusing? / Extends with Focusing?Y / N
Lens Hood Size (DxL)3.37 x 2.11”  (85.7 x 53.7mm)
Lens Length with Hood (Min-Max)5.77 – 5.77”  (146.6 – 146.6mm)
Size of Rings: Focus / Zoom1.37”  (34.8mm)
Filter Size67mm 
Front Element (Filter Mount) RotatesN
 
Focus  
AF Motor TypeHSM
Full Time Manual FocusY
Focus Ring Rotation97°
Focus Limiter? / Focus Limiter RangesN
Distance Scale? / TypeY / Window
 
Close Focus  
Specified Min Focus Distance11.81”  (300mm)
Tested Min Focus Distance (Wide / Long)11.42”  (290mm)
Maximum Magnification (MM)0.19x
 
Features  
Tripod Ring Included? / Removable?N
Lens Hood Included / Model?Y /
Weather Sealed? / Filter Required?N
Image Stabilization? / Stops? / Tripod Sensing?N
Extender Compatible?N
Case Included? / Type?Y / Padded Nylon
47.25″ x 31.5″ Subject Framing Distance35mm = 4.10′
1200mm x 800mm Subject Framing Distance35mm = 1250mm
 

Rokinon 24mm f/1.4

The Rokinon 24mm f/1.4 ED AS UMC Wide-Angle Lens for Nikon gives you a wide 84° view when used with a full-frame 35mm camera, or 57.6° when used with an APS-C camera–excellent for landscapes, cramped interiors, street photography and general photography of all kinds. Four low-dispersion (ED) glass elements and two aspheric elements produce sharply defined images with a minimum of flare and ghosting. The lens focuses as close as 9.84″ from the lens, giving you outstanding wide-angle close-up views. A multi-layered and anti-reflection UMC coating provides superb light transmission. This lens will operate in Aperture Priority, Shutter Priority, Program, and Manual exposure modes. It features an Automatic Chip for focus confirmation and aperture and other setting adjustments directly from camera’s interface. 

Aperture  
Aperture Range – Wide / Longf/1.4-22
Number of Aperture Blades8
Rounded Aperture?
 
Weight  
Manufacturer Specification Weight19.4 oz  (550g)
Actual Weight19.4 oz  (550g)
Lens Hood Weight0.9 oz  (25g)
In-Use Weight20.3 oz  (575g)
 
Size  
Manufacturer Spec Size (DxL)3.27 x 3.74”  (83 x 95mm)
Measured Size (DxL)3.25 x 4.02”  (83 x 102.2mm)
Max Length at Full Extension4.02”  (102.2mm)
Internal Focusing? / Extends with Focusing?Y / N
Lens Hood Size (DxL)3.9 x 1.94”  (99 x 49.3mm)
Lens Length with Hood (Min-Max)5.8 – 5.8”  (147.2 – 147.2mm)
Size of Rings: Focus / Zoom1.78”  (45.2mm)
Filter Size77mm 
Front Element (Filter Mount) RotatesN
 
Focus  
AF Motor TypeMF Only
Full Time Manual Focus
Focus Ring Rotation138°
Focus Limiter? / Focus Limiter Ranges
Distance Scale? / TypeY / Printed
 
Close Focus  
Specified Min Focus Distance9.84”  (250mm)
Tested Min Focus Distance (Wide / Long)9.65”  (245mm)
Maximum Magnification (MM)
 
Features  
Tripod Ring Included? / Removable?N
Lens Hood Included / Model?Y /
Weather Sealed? / Filter Required?/ N
Image Stabilization? / Stops? / Tripod Sensing?N
Extender Compatible?N
Case Included? / Type?Y / Pouch
47.25″ x 31.5″ Subject Framing Distance24mm = 3.04′
1200mm x 800mm Subject Framing Distance24mm = 927mm

Sigma 85mm f/1.4

The Sigma 85mm 1.4 DG HSM Art is a latest addition to the world renowned Sigma Global Vision Line. Designed and engineered for unparalleled image quality, the Sigma 85mm 1.4 Art employs a completely new optical design and premium components. 2 FLD (performance equal to fluorite) glass elements and 1 element boasting a high rate of anomalous partial dispersion and high refraction achieve a class leading level of performance. The highly anticipated 85mm 1.4 Art is an ideal lens for a variety of photographic subjects, particularly portrait photography, both in-studio and on-location. The newly updated Hyper Sonic Motor (HSM) allows for 1.3X the torque of previous generations for fast and efficient autofocus. Through rigorous testing, the Sigma 85mm 1.4 Art ushers in a new era of quality and performance for this popular fast prime focal length. A 9-blade rounded diaphragm creates beautiful background bokeh to isolate and accentuate the subject. Full Time manual focus can be engaged by rotating the focusing ring, even when shooting continuous autofocus.

Lens construction14 elements in 12 groups
Minimum apertureF16
Filter sizeφ86㎜
Angle of view (35mm)28.6°
Minimum focusing distance85cm / 33.5in.
Dimensions (diameter × length)φ94.7mm × 126.2mm / 3.7in. × 5.0in.
Number of diaphragm blades9 (Rounded diaphragm)
Maximum magnification ratio1:8.5
Weight1,130g / 39.9oz.
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