This lens, already available in Sony E mount, will soon be available in Nikon Z mount. Using the specs in this article and converting from grams to pounds, it will weigh 2.6 pounds. That is a full pound lighter than their existing 150-500 for Z mount with collar removed (and almost a pound and a half lighter with collar attached). It is also half a pound lighter than Nikon Z 100-400 with foot attached (and even still lighter than that lens with foot removed). I assume the Tamron weight is without the optional tripod collar, since it is not included and only available as an accessory purchase (based on listing for Sony E mount).
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Details of the upcoming Tamron 50-400mm f/4.5-6.3 Di III VC VXD lens for Nikon Z-mount leaked online - Nikon Rumors
Here are all the leaked details and pictures of the upcoming Tamron 50-400mm f/4.5-6.3 Di III VC VXD lens for Nikon Z-mount (the lens already exists for Sony E-mount – priced at $1,299): The TAMRON 50-400mm F4.5-6.3 VC is a compact ultra-telephoto zoom lens for mirrorless system cameras with...
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