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Old Aug 18, 2013, 08:44 PM
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United States, MA, Walpole
Joined Dec 2003
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Clarified lens styles in attachment comments

I am pleased to finally be able to give definitive information on a new wider AOV lens for the Mobius, being referred to as Lens B (the original wide AOV lens is designated as Lens A). This is the same lens I have had for testing for a couple months now, made in Japan with 7 quality optical glass elements. This gives excellent image corner-to-corner sharpness, contrast, and color uniformity, with negligible vignetting.

With current FW v0.41, the horizontal field of view (HFOV) of this new lens in 1080p-30fps mode is about 116 deg. by my measurements. In 720p-60fps mode the HFOV is about 63 deg. and in 720p-30 fps mode, the HFOV is scaled and identical to the 1080p-30 fps mode (116 deg.). Compare this with the existing standard Mobius lens which has HFOV of about 85 deg. and 46 deg., respectively. In still photo mode set for maximum 2304x1536 pixel size, the wider lens gives a HFOV of about 118 deg. from the 3:2 aspect ratio imager CMOS array, but some corner vignetting will be evident at that frame size.

The new lens will add about 2 gms of weight to the camera weight compared to the standard lens.

The projected cost of this new lens from the China verified sellers is about $13 US (delivered) for the lens only, and about $27 US (delivered) for the complete lens/CMOS module. Availability is uncertain (lenses have been ordered), but is hoped to be early to mid Sept. 2013 from the China eBay sellers. Pricing and availability from verified resellers will likely be a bit higher/longer. Contact your favorite verified vendor for their most current information on this lens.

This video shows a side-by-side comparison of the standard (Lens A) vs. the new wider AOV (lens B) in both 1080p - 30fps mode and 720p-60 fps mode. Note the two lenses have their own hue attributes, with the standard Lens A being on the "warm" side and the new wider Lens B being on the "cool" side. The FW used to shoot these samples was an older version, and has been updated with user toggles for Lens A and Lens B to give better (but not identical) auto-white balance qualities for each lens.
Wider Lens vs Standard (0 min 28 sec)



Attached are some pictures of the lens and how it fits in the black release version of the Mobius case. NOTE: This lens is not compatible with the early gray colored pre-release cases (without some case hacking on the user's part). The lens will thread into the standard CMOS module, and can be retrofitted into an existing CMOS module by loosening the lens securement set screw, unscrewing the standard lens , and reversing the procedure to install the new lens. Of course, you will also need to focus the new lens.

Note how the black case design has two ribbed CMOS module pocket seats in it. This new lens protrudes through the standard lens hole in the case (no hacking needed), and the CMOS module must be seated in the forward pocket seat to get the case halves back together.
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Last edited by Tom Frank; Jan 18, 2015 at 11:55 AM. Reason: added new lens name designations (Lens A & B) and new FW note
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