small aperture test
in [Digital Cameras]
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From: Outing Trolls is FUN! on 6 Nov 2009 05:17 On Fri, 06 Nov 2009 09:50:52 +0100, Ofnuts <o.f.n.u.t.s(a)la.poste.net> wrote: >Trolls is FUN! wrote: >> On 06 Nov 2009 07:28:51 GMT, rfischer(a)sonic.net (Ray Fischer) wrote: > ><snip prespoterous claims> > >> >> YOUR LOSS! >> >> And a huge loss for everyone. Caused by trolls like you. Now everyone has >> to do the searching for that software based only on a vague description. >> Good luck finding my most favorite and vastly configurable one as described >> above, I've not seen it on the net for about two years. You useless trolls >> taught me well. NEVER share the most important bits of information as long >> as a news-group is being overrun and taken over by a pack of useless and >> pathetic trolls. The trolls will only use that information to be better at >> pretending to be photographers with the next newbies who can't immediately >> see the trolls for what they truly are. > >I don't believe this stuff exists. Prove me wrong! I suppose I could upload two sample images, one without and one with a depth-map catadioptric-lens annulus bokeh applied to it, but ... why waste my time doing that for useless trolls? Why should I even prove you wrong? You love being right! Don't you? Whether you believe I am telling the truth or not is of zero importance to me. I enjoy using that software occasionally when needed. My favorite one does a remarkable job of emulating any lens bokeh that you can think of or have ever seen before. The only difference is that you have no knowledge of its existence, until now. Oh well! Unimportant to me. Should I tell you the names for the plugins so role-playing trolls can learn to be better trolls? Just like the only contact they ever have with cameras is from downloading free camera manuals. They'd then have some advanced plugin information so they can pretend to be decent graphic editors too. They're so fuckingly transparent to someone like me when they pretend to be photographers in these news-groups. They just refuse to understand that yet, or they'd go play their silly pretend-expert games elsewhere. Go forth and search! You have enough information in the previous post to find what you seek. Blame all the useless resident-trolls that you support (or are one yourself) for not having the information just handed to you for free. Now you have to do some work to go find the software. Be extremely grateful that I was kind enough to tell you that software of that nature even exists. Have fun! (Awaiting your next, or some other troll's, pathetic manipulation attempt--to get some help that you don't even deserve, for free.)
From: Outing Trolls is FUN! on 6 Nov 2009 05:18 On Fri, 06 Nov 2009 09:25:59 +0000, Martin Brown <|||newspam|||@nezumi.demon.co.uk> wrote: >Ofnuts wrote: >> Trolls is FUN! wrote: >>> On 06 Nov 2009 07:28:51 GMT, rfischer(a)sonic.net (Ray Fischer) wrote: >> >> <snip prespoterous claims> >> >>> >>> YOUR LOSS! >>> >>> And a huge loss for everyone. Caused by trolls like you. Now everyone has >>> to do the searching for that software based only on a vague description. >>> Good luck finding my most favorite and vastly configurable one as >>> described >>> above, I've not seen it on the net for about two years. You useless >>> trolls >>> taught me well. NEVER share the most important bits of information as >>> long >>> as a news-group is being overrun and taken over by a pack of useless and >>> pathetic trolls. The trolls will only use that information to be >>> better at >>> pretending to be photographers with the next newbies who can't >>> immediately >>> see the trolls for what they truly are. >> >> I don't believe this stuff exists. Prove me wrong! > >Google is your friend. > >One such plugin is even unimaginatively called "Bokeh". I don't like the >results but then I have never been into lenses smeared in vaseline etc. eg. > >http://alienskin.com/bokeh/index.aspx > >Can't say I would recommend it. > >Regards, >Martin Brown Never used that one. And from your description I probably won't even test it.
From: Ofnuts on 6 Nov 2009 06:49 Outing Trolls is FUN! wrote: >> I don't believe this stuff exists. Prove me wrong! > > I suppose I could upload two sample images, one without and one with a > depth-map catadioptric-lens annulus bokeh applied to it, but ... why waste > my time doing that for useless trolls? > > Why should I even prove you wrong? You love being right! Don't you? No, I love to learn... even from my errors. > Go forth and search! You have enough information in the previous post to > find what you seek. Obviously not, since someone thought the same, and found the "wrong" one according to you. > (Awaiting your next, or some other troll's, pathetic manipulation > attempt--to get some help that you don't even deserve, for free.) I'm not awaiting help, at least not from you obviously, since, being part of the crowd of DSLR dummies/minions/trolls I don't need this software. I am awaiting some proof of your claims. Einstein did make some that where preposterous at the time, but he also gave ways to prove them. And this means giving enough information so that the people in doubt can check by themselves (I still have a P&S somewhere). So either you prove me wrong, or you prove yourself a <insert derogatory term here> -- Bertrand
From: Rich on 6 Nov 2009 12:21 On Nov 5, 9:26 am, Martin Brown <|||newspam...(a)nezumi.demon.co.uk> wrote: > Dudley Hanks wrote: > > "David J Taylor" > > <david-tay...(a)blueyonder.not-this-bit.nor-this.co.uk.invalid> wrote in > > messagenews:t6aIm.1501$Ym4.551(a)text.news.virginmedia.com... > >> "Dudley Hanks" <> wrote in messagenews:4U9Im.50459$Db2.29545(a)edtnps83.... > >>> I've heard a lot about how the cropped sensor cameras are defraction > >>> limited to around f/8 - f/11, so I thought I'd see what kind of an image > >>> my XSi puts out at a small aperture. > > >>> I snapped on my 50mm f/1.8 lens and set it up to take a picture at f/22, > >>> with a shutter speed of 1 sec. > > >>> How did it turn out? > > >>>http://www.snaps.blind-apertures.ca/images/SmallWinterPortrait.jpg(quick > >>> download) > > >>>http://www.snaps.blind-apertures.ca/images/SelfPortraitWinter.jpg (full > >>> size) > > >>> Take Care, > >>> Dudley > >> Difficult to say, Dudley. Yes, the image isn't "tack sharp" (a term I > >> loathe), so there could be some diffraction visible, but I'm also not > >> convinced that the subject didn't move within the 1 second exposure! > > > Thanks, David, I'll try it again with an inanimate object, or a faster > > shutter speed. > > > I suppose, if the test is to be useful, I should also take an equivalent pic > > of the subject using a wider aperture so the two images can be compared.. > > If you are serious about being able to tell include a few ball bearings > on black velvet in the picture composition. Specular highlights are > about the easiest thing to see if an image is diffraction limited. > > Or you could just use a pinhole over the lens and a verry long exposure. > > Regards, > Martin Brown Not much point in using a pinhole, any lens will show as diffraction limited stopped down enough. I have a feeling most lenses stopped down to f8 "act" diffraction limited centrally, but the edges of most lenses are never diffraction limited and poor polish and surface figures on most camera lenses mean you never reach true diffraction.
From: Educationg Trolls Is An Endless Task on 6 Nov 2009 16:04
On 6 Nov 2009 14:50:57 GMT, Chris Malcolm <cam(a)holyrood.ed.ac.uk> wrote: > >Not at all. I've worked alongside colleagues who've written books on >the subject. When a youth was giving himself airs in the Theater and saying, "I am wise, for I have conversed with many wise men." Epictetus replied, "I too have conversed with many rich men, yet I am not rich." You were saying something? LOL! I'm sure your colleagues, if you indeed ever had any, kept you around as their little puppy dog that didn't piddle on the carpet too often. Or conversely, got many laughs out of your incessant piddling habits. As I do with how often you piddle your nonsense to usenet. Pushing a broom and emptying waste-baskets in a publisher's collating department could also be construed as "working alongside .... (authors)". If I was forced to assume your trolls' comment above was conveying your truth, from the vast amount of misinformation you spew that would be my guess of how you came to believe what you believe. > The mathematics of the relationship between lens optical >aberrations and diffraction is simple, uncontroversial, and has long >been well known. Your position can only logically be maintained if you >disagree with one of the following propositions: > >1. Lens optical errors vary inversely with aperture. Wrong. The central part of a lens or lenses may have the greatest figure error. Especially in a complex compound lens where one element or group of elements may have more imaging weight as aperture is increased or reduced. However, for a given amount of effort, fabrication and figuring errors are exponentially proportional to size. There is no law on which area of that lens may have the greatest error. Common Sense 101 > >2. Lens diffraction errors vary with aperture. Wrong. It varies with distance of aperture edge to imaging plane. The amount of light in the image only reveals or hides the fixed amount of diffraction created/caused by distance. You can display the diffraction of light with a single knife-edge, no aperture required. This is why shorter focal-length lenses have less diffraction problems. This also is why it's so easy to create truly diffraction-limited optics for P&S cameras due to the smaller focal-lengths required and smaller optics diameters required (i.e. for a given effort, a smaller diameter optic is easier to figure accurately). Physics 101 Manufacturing 101 > >3. Lens errors combine at worst multiplicatively. Wrong. Grade-School Math 101 > >Can you enlighten us as to which of those you disagree with, or >whether you're using a different mathematical foundation for the >relationship? Three strikes, you're outta here TROLL. Blatantly Obvious 101 |