On Thu, Apr 23, 2009 at 11:41 AM, Graydon <[email protected]> wrote: > On Thu, Apr 23, 2009 at 11:20:23AM -0400, Adam Maas scripsit: >> On Thu, Apr 23, 2009 at 10:00 AM, Graydon <[email protected]> wrote: >> > On Thu, Apr 23, 2009 at 10:14:41AM -0300, Luiz Felipe scripsit: >> >> EVF with a mirror camera? Lose the pentaprism and keep the mirror? >> >> Lose the prism and mirror but keep the camera otherwise the same?? >> > >> > Keep the direct optical path to the viewfinder; lose the moving mirror >> > and shutter. >> > >> > Ideally, this and the robustness deal gets the LCD off the back of the >> > camera -- big flat fragile space that it is -- and replaced with a >> > HUD-style overlay in the viewfinder. The back can then support >> > larger/more controls. (Using the K20D 4-direction rocker dial with >> > gloves? Ick.) >> > >> > However, the main thing is to get the electro-mechanical stuff out of >> > the optical path. >> >> I'd rather just ditch the mirror altogether. It's the biggest weakness >> of SLR's, since it affects AF accuracy and VF focusing accuracy. > > No mirror, just a prism, is probably one of the pure-optical choices. > > It's very hard to support a separate shutter as a design decision in an > EVIL camera -- extra parts, mass, etc. -- but it also involves ditching > K-mount lens back compatibility if you do that. Pentax doesn't want to > do that; there's that cryptic statement in support of K-mount from a > couple-three months back.
Actually the shutter is easily justifiable for the same reason as on any interchangable lens camera. Keeps lens cost down and lens complexity down. There's no reason an EVIL camera has to give up full K mount compatibility. Lens shutters make little sense outside of the MF world where they allow reasonable sync speeds compared to the low sync speed that massive focal plane shutters are restricted to. > > If they want to keep lens compatibility, they can't go EVIL in a > sensible way, so presumably they're looking at something else. > >> EVIL is inherently more accurate for both manual focus and AF since >> you're focusing off the imaging sensor itself. Don't ditch the LCD >> until you've spent time with a good Live View camera with a flip/twist >> LCD. It changes the game entirely. > > First camera was a Konica-Minolta A200. I still have it. > > It has unquestioned and numerous virtues, and it made me want a pure > optical viewfinder so very much. (This may have something to do with > having expended rather a lot of Her Majesty's ammunition in my mis-spent > youth, I don't know.) Next camera was an LX2. There's nothing wrong > with it, for what it is, but I didn't love it. > > I strongly suspect this is one of those issues of personal style. Try a G1. The EVF on that (or any pro video kit) is to the A200's EVF as the VF on a Sony A900 is to the E-420's VF. Whole different world of performance. > >> >> The moment I think of EVF I also think of a mirror-less camera, >> >> with a distance from lens mount to sensor as reduced as possible, >> >> with new lenses to exploit the advantages AND a very good adapter >> >> to the former lens format of the brand. AND a side adapter for all >> >> major lens mounts, even if I'd sell it under a very different >> >> brand. >> > >> > That's what the Samsung NK is supposed to do. I get the feeling >> > that's not where Pentax wants to go. >> > >> > Straight EVIL does two things Pentax wouldn't like; it starts to use >> > the lens aperture mechanism as the shutter, which means you lose >> > lens backward compatibility, and it almost completely de-values >> > optical design in the camera. Pentax is still primarily, >> > nigh-obsessively, an optical company. They want to keep competing >> > inside their area of speciality if they possibly can. >> >> The G1 uses a normally-open shutter. No lens-based shutter systems. > > Yup. And that is probably not the right engineering decision if you > have to design new lenses anyway. Actually, it's pretty much a given, especially if you're already putting IS systems in the lens (as Panny is doing). Camera shutters are more reliable, allow higher max shutter speeds and don't require the user to buy a new shutter every time they buy a new lens. The lens shutter on small interchangeable lens cameras has never been a viable option. > > If they change the registration distance, Pentax would have to design > new lenses, and I suspect but of course cannot prove that avoiding loss > of back-compatibility is a major goal for them. true, but adaptability is possible. Would probably mean giving up non-SDM AF support (there'd only be room in the adaptor for a stop-down motor) but compatibility is not a huge issue when you're talking 20+mm of register difference. Heck, Pentax has done that before (645/67 and K/645). > >> And the introduction of digital nearly completely devalued optical >> design in the body. The EVIL concept is just taking it to the next >> step. > > That assumes you can get the view off the sensor or the view off the > optical path, but not both at once. If you can do both at once -- and > that Zeiss Photoscope announcement indicates that somebody can do both > at once -- the designer has the option of valuing optical design in the > body. Doing both at once means a pellicle mirror or partially silvered prism with regular mirro. Which is a poor design choice for a dedicated camera as history has proven. And you lose the advantage of the guaranteed focus accuracy. > >> > I'm not expecting a revolution either, but, Hoya needs one, and Mike >> > Johnson deferred his camera #2 recommendation today; "This is >> > awkward, but I'm going to have to hold off with #2 until about this >> > time next month. Still collecting data. What can I say—this slot was >> > solid ten days ago, but the world changes." >> > >> > You know of any other plausibly-better-than-"A mid-level 4/3 or >> > APS-C DSLR of the brand of your choice" -- which is recommendation >> > #3 -- that's going to be announced in a month? I'm certainly not as >> > well-plugged into the rumour mill as I could be. >> > >> > Mike certainly gets the lenses early. He's had a K20D on long-term >> > loan for almost a year now. So it's not impossible he's got enough >> > insider info on the successor camera to decide to hold on on >> > recommendation #2. >> >> Its possible. It's also possible that he's actually read the bitching >> on the comments about the E-420 pointing out that he picked the camera >> with the worst VF and worst ergonomics in-class and realized that he >> should have either gone with his first choice (any low-end DSLR) or >> picked a camera that actually delivered on its promises (like the K-m >> or A200). > > Well, the E-420 was a pure price pick, and possibly defensible on those > grounds. I certainly know someone with an Olympus SLR who does not use > the viewfinder, at all, ever, too, which makes me twitch to contemplate. > > In a month or so, we'll have lots more information, too. > > -- Graydon > A200 is a better pure price pick, as is the K2000. -- M. Adam Maas http://www.mawz.ca Explorations of the City Around Us. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
