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Message: <blockquote data-quote="Themoog" data-source="post: 3522748" data-attributes="member: 140925">I was always taught that depth of field relates to lense focal length and apeture.At any given point of critical focus,depth of field, or acceptable focus, extends both forward and backwards (closer/further) from this critical plain in a ratio of roughly one third in front to two thirds behind the critical plain.Whilst this ratio remains constant, the distances each depth represents varies with not only the variables mentiones above but also the distance at which one sets critical focus from the focal plain.It is of course also known that telephoto lenses have the effect of 'compressing' our sense of relative depth perception with this effect being more apparent in longer lenses and less so as we move back towards a 50mm (in 35mm camera format or its equivalent) which shows objects at the same relative distance to each other as the human eye.As much as I am enamoured by Leica and indeed may end up buying a pair (they're certainly in the mix), at this point and in light of what is stated above I would be rather sceptical of any such chimera as 3D.Remember, Leica is only suggesting, in it's marketing material at that, a (I paraphrase from other posts on this forum having not yet pored over the Leica catalogue myself) '3d like effect' ('like' & 'effect' being operative here). As for plasticity, well, a jolly comprehensive thesaurus and a stein or two of Warsteiner, Krombacker, Bitburger or any other of Germany's unsurpassed, reinheitsgeburt compliant (i.e. any of them) pilsners might explain all one needs to know.Side note: could you chaps get on with educating our pub culture that the corolary of cask ale in lager is NOT Fosters?(no disrespect to our Australian friends but I know even you guys don't drink it having travelled there).Who knows how long one has to live and I look forward to the recent  and healthy enthusiasm we have for real ale in th UK being reflected in high quality european blonde beers before I die. ...please !Back on topic.I'm not flatly contradicting those that appear to see such an effect, albeit fleetingly and in seemingly unreplicatable ways. Since porros regularly seem credited with being able to offer up an effect in a more replicatable fashion I would probably throw into the mix, like fuel on a fire perhaps, something broadly within the realm of parallax and prismatic corrections. Combine that with DOF , what appears to be genuine and well intentioned enthusiasm on the part of some and probably leave it at that. In certain conditions, a perfectly focussed lense, at the right distance with very good optics (and all of the planets in the right configuration - so to speak ) can give us a view that is simply so breathtaking that it temporarily blocks out the backgrond hum of life and puts us in the immediate moment with nature. An optically perfect moment if you will.Of that I have no doubt.The glint of light off the custard yellow ring in a male blackbirds eye against a deep black and almost dusty but pristine wings folded away and that proud, listening tilt of the head. 99 out of a hundred times, beautiful. One in a hundred- breathtaking.3D? No.3D-like effect? With a degree of poetic license permitted - why not - caveat emptor.(Note to Zeiss and Swarovski: Come on guys, you need to up the stakes in your next catalogue. Might I suggest, in the spirit of one Edmund Blackadder, trying to shoehorn the word, 'Contraphibulations' in there somewhere? - he he he)My last thought is this;One of the very few things that I remember from my much missed physics teacher is the following;'The propogation of light is rectilinear'(Runs for cover clutching imported and beloved bottle of Bitburger, a dunkel glass and one of those little paper doilies that catches the drips and condensation)All the best, Tm</blockquote>

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