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<blockquote data-quote="WayneF" data-source="post: 379359" data-attributes="member: 12496">Well, the one is f/1.8.&nbsp; &nbsp; Which means the lens is larger diameter, relative to its focal length.&nbsp; And large diameter lenses are simply more expensive to make, harder to make good.fstop number is focal length / aperture diameter (which is actually the front element effective diameter).So 35mm f/1.8 is 35/1.8 = 19.4mm diameterand 18mm f/3.5 is 18/3.5 = 5.1mm diameter (and 10mm at 35mm f/3.5).The larger lens has to be ground accurately way out to 19mm diameter.&nbsp; And it has several elements needing this accuracy.&nbsp; This is harder to manufacture.&nbsp; Wide apertures are expensive. Many of the Nikon f/2.8 zooms cost up near $2000, and there are no f/1.8 zooms - too expensive and difficult.I would certainly start with the 18-55 zoom.&nbsp; It is vastly more versatile, and it will do 35mm too.&nbsp; Phones typically do not zoom, but point&amp;shoot compacts did.&nbsp; Same thing, more versatility, wide angle to telephoto (in some degree).The 35mm f/1.8 does offer f/1.8, which if 1.8 is used, it is a specialty or novelty feature, not for general purpose at all.&nbsp; It is good to normally use f/5.6 or f/8 for general purpose (sharper, more depth of field).&nbsp;&nbsp; And the 35mm probably is a little sharper lens (higher price - certainly better at wide apertures like f/3.5), but it only does 35mm.&nbsp; 35mm is the number you would want if you only had one focal length, but you can have from 18 to 55 mm instead.</blockquote>

[QUOTE="WayneF, post: 379359, member: 12496"] Well, the one is f/1.8. Which means the lens is larger diameter, relative to its focal length. And large diameter lenses are simply more expensive to make, harder to make good. fstop number is focal length / aperture diameter (which is actually the front element effective diameter). So 35mm f/1.8 is 35/1.8 = 19.4mm diameter and 18mm f/3.5 is 18/3.5 = 5.1mm diameter (and 10mm at 35mm f/3.5). The larger lens has to be ground accurately way out to 19mm diameter. And it has several elements needing this accuracy. This is harder to manufacture. Wide apertures are expensive. Many of the Nikon f/2.8 zooms cost up near $2000, and there are no f/1.8 zooms - too expensive and difficult. I would certainly start with the 18-55 zoom. It is vastly more versatile, and it will do 35mm too. Phones typically do not zoom, but point&shoot compacts did. Same thing, more versatility, wide angle to telephoto (in some degree). The 35mm f/1.8 does offer f/1.8, which if 1.8 is used, it is a specialty or novelty feature, not for general purpose at all. It is good to normally use f/5.6 or f/8 for general purpose (sharper, more depth of field). And the 35mm probably is a little sharper lens (higher price - certainly better at wide apertures like f/3.5), but it only does 35mm. 35mm is the number you would want if you only had one focal length, but you can have from 18 to 55 mm instead. [/QUOTE]

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