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July 12, 2014
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Posted in News

10 Canon 400mm Lenses Used To Detect The Faint Structures Of The Universe

Canon 400mm
The Dragonfly with 8 lenses mounted – image © Dunlap Institute for Astronomy and Astrophysics

Thanks Chris

Dragonfly is a project by the Dunlap Institute for Astronomy and Astrophysics in Toronto, Canada. It consists in a multi-lens array designed for ultra-low surface brightness astronomy at visible wavelengths. It uses 10 commercially available Canon 400mm lenses. The lenses in the picture above seem to be Canon EF 400mm f/5.6L USM lenses.

The project was commissioned in 2013. The lens array should be capable of detecting the obscure and utterly complex structures that can be found around a galaxy:

According to Cold Dark Matter (CDM) cosmology, structure in the Universe grows from the “bottom up”, with small galaxies merging to form larger ones. Evidence of such mergers can be seen in faint streams and filaments visible around the Milky Way Galaxy and the nearby M31 galaxy.

Dragonfly is used to find those structures. How does it work?

Dragonfly is designed to reveal the faint structure by greatly reducing scattered light and internal reflections within its optics. It achieves this using ten, commercially available Canon 400mm lenses with unprecedented nano-fabricated coatings with sub-wavelength structure on optical glasses.

The Dragonfly project is funded by DAA Prof. Roberto Abraham’s NSERC Discovery Grant, with initial funds provided by the Dunlap Institute and Yale University, and an NSERC equipment grant awarded in 2013.

For more information head over to the Dunlap Institute’s site.

 

 

June 21, 2014
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Posted in patents

Canon Patent For 400mm f/4 IS DO Lens

Canon Patent

Egami (translated) spotted a patent filed by Canon for a 400mm f/4 IS DO (diffractive optics) lens.

  • Patent Publication No. 2014-109700
    • Publication date 2014.6.12
    • Filing date 2012.12.3
  • Example 1
    • Focal length f = 392.00-381.59-332.99mm
    • Fno.
    • Half angle ω = 3.16-3.10-2.81 °
    • Image height Y = 21.64mm
    • The overall length of the lens 292.02mm
    • BF 105.64mm
December 27, 2013
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Posted in Rumors

Canon Rumor: New EF 400mm IS on the Way?

Canon Rumor

Canon EF 400mm f/5.6L USM: Amazon, B&H, Adorama, Canon USA, J&R, Digitalrev, Borrow Lenses, eBay

It appears that stocks for the EF 400mm f/5.6L USM are getting low in some regions, and promptly there is a rumor suggesting a new EF 400mm f/5.6 with image stabilisation may be on its way. There had previous rumours that 2014 could be a “year of the lenses” for Canon, with lot of glass set to come. We haven’t heard anything about a possible successor of the EF 400mm, but then: the EF 400mm was released in 1993 so a makeover has some plausibility. As usual take it with a grain of salt and keep in mind that only time will tell.

[via NL]

October 30, 2013
Posted in Rumors

More Sigma “Sport” Lenses Coming in 2014

Sigma "Sport" Lenses

Sigma 18-35mm f/1.8 DC HSM
Amazon, B&H, Adorama, Canon USA, J&R, Digitalrev, Borrow Lenses, eBay

It appears that Sigma will enjoy us with more lenses based on their new technology. Various lenses that will be part of the “Sport” line-up may be announced. The rumor fits with the rumored list of next Sigma lenses we posted aome time ago.

The rumor has word that Sigma will announce first a 300mm f/2.8 OS and a 400mm f/2.8 OS lens. These lenses may be undergone field-testing during the Winter Olympic Games. The other lenses Sigma is said to work on are a 500mm and a 800mm lens.

I can just hope Sigma will again be able to pack all the engineering wizardry they put into the awesome 18-35mm f/1.8 DC HSM and 35mm f1.4 DG lenses.

[via CR]

December 19, 2012
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Posted in patents, Rumors

Rumor: A Bunch Of 400mm Lenses To Be Announced In 2013?

This Canon EF 400mm f/5.6L USM Autofocus Lens

That's what Canon Rumors has been told, that we can expect up to four new lenses in the 400mm range. Quoting:

Below are lenses that are apparently in prototype form and are on tap to be announced in 2013.

    • EF 400 f/5.6L IS (Highly desired)
    • EF 400 f/4L IS (Not DO)
    • EF 100-400 f/4-5.6L IS (Not push-pull & patents exists)
    • EF 200-400 f/4L IS 1.4x (Long known about)

[via CR]

 

September 26, 2012
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Posted in Reviews

Canon EF 400mm f/2.8L IS II USM Field Review And Test

EF 400mm f/2.8L IS II USM settings. Image courtesy of Digital Photography School

This is a good and instructive review of the EF 400mm f/2.8L IS II USM ($11,500, click here) by Digital Photography School. Let me first list the specifications of the lens:

  • L-Series Optics
  • Optical Image Stabilization – 3 Modes
  • Fast Ultra-Sonic Motor (USM) Autofocus
  • Full-time Manual Focusing Functionality
  • High-speed CPU
  • Autofocus Stop Feature
  • Dust and Water Resistant
  • Fluorite Glass for Improved Quality
  • Protective Fluorine Lens Coating
  • Security Slot for Wire-Type Locks

The review comes with lots of samples (wildlife shots in Alaska). From the conclusion:

The Canon EF 400mm f/2.8L IS II USM is a treat to use but not a treat to carry around. It is best used when a base of operations can be established, like a boat or near a campsite. The sharpness from side to side is impressive but needs to be balanced with the general aspect of it being a fixed focal length lens. This is fairly easily overcome with cropping final images, especially as the pixel count on future cameras climbs.

EF EF 400mm f/2.8L IS II USM price check: Amazon, B&H, Adorama, Canon USA, J&R, Digitalrev, Borrow Lenses, eBay

[via DPS]
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