ho_co Posted September 20, 2007 Share #361 Posted September 20, 2007 Advertisement (gone after registration) ... Let's assume the camera is tripod mounted, and the mount is directly over the film plane ... But how often is that assumption correct? I don't know of any camera whose tripod socket is over the film plane. Michael's point isn't that easy to comprehend at first. It took me a while to get my head around it. In another thread (on backfocus of some of Tim Ashley's lenses), I argued a fair amount before I finally began to see the accuracy of his logic. --HC Link to post Share on other sites More sharing options...
Advertisement Posted September 20, 2007 Posted September 20, 2007 Hi ho_co, Take a look here Is R10 or a brand new Digital-R coming ?. I'm sure you'll find what you were looking for!
Likaleica Posted September 20, 2007 Share #362 Posted September 20, 2007 Suppose you want to take a photo of a group of people, and you have all of them line up in front of your camera – in a straight line that is perpendicular to the optical axis. If you focus on some person in the middle, everyone else’s image should be just as sharp, right? But then, those at the extreme left or right are farther away from the camera than someone in the middle is. Shouldn’t you rather draw a circle with the camera at the center and have everyone stand on that circle? That’s what your theory predicts you should do, because only then would everyone be equally far away from the camera. Got it. Sehr gut! Vielen Dank!! Link to post Share on other sites More sharing options...
jank Posted September 20, 2007 Share #363 Posted September 20, 2007 Wilson is right, Zeiss Planars belong to this family. They project plane to plane. I used it also as enlarging lens for that reason. It just projected image back this time to the paper, correcting for all nonlinearities. It looks like one has to run few experiments and then perhaps arrange the group accordingly. The particular lens may not project equidistant objects to the film/sensor plane. With todays perfectly flat sensors with resolution exceeding that of the film and open aperture one should take it to consideration. Jan Link to post Share on other sites More sharing options...
telyt Posted September 21, 2007 Share #364 Posted September 21, 2007 ... We focus on our subject, say the catchlight in a bird's eye. This is Distance A. We then recompose, moving the bird to the side of the frame. The distance from film plane to bird's eye has not changed. In the time it takes to re-compose the bird will have moved so the eye is no longer in the plane of focus. I tried the F-L-R technique with this bird (below) and every time I used the center of the viewfinder to focus, then re-composed, the bird shifted its weight from one foot to the other or turned to look at something or reached for a morsel so that its eye was no longer in the (very narrow) plane of focus. The only photos in this series that were properly focussed on the eye were those where I focussed as-composed. Link to post Share on other sites More sharing options...
Likaleica Posted September 21, 2007 Share #365 Posted September 21, 2007 There you go again with another great shot! If that was taken using my 1.4 apo-extender, I want half credit!! Link to post Share on other sites More sharing options...
EH21 Posted September 21, 2007 Share #366 Posted September 21, 2007 I think you're worrying too much, Eric. The Olympus E-1 only has 3 AF points and that doesn't stop people from calling it a "professional" camera and there's just a lot of rave about it. The frame coverage of your 6008 is so much bigger than 35mm coverage so the negative effect is obviously more pronounced. I think AF is a rather mature technology now, even the Pentax K100D could have 11 points, and the Canon 40D makes all 9 points cross type ... let's hope for the best and prepare for the worst. LOL Yes, you may be right. I shouldn't worry too much about a product that I have no control over. However, I was just pointing out that all the people that have AF on their wish list for the new R may not know what they are asking for. Were they better informed they might well choose a bigger brighter viewfinder instead. I can tell you after using the 45 selectable points on the canon 1Ds the 9 on the 5D is not enough. When you shoot with a 80 lux at a model in a range close enough to keep chemistry going between photographer and model, you will find that even small errors in focus kill the image. The DOF is that small. You really can't use 3 or 9 points and get what you want. Sure the charts will give you 2 cm's for DOF but remember that's minimum acceptable sharpness on the outside edges of DOF and that minimum was mostly specified before the advent of digital sensors. If you use two sencel widths for the circle of confusion in your DOF calc's, or for even more critical work or larger prints 1 sencel width then the DOF is just tiny. What I'm working towards in my posts here, is to point out that we all want the next R to enable users to focus accurately. AF with only a center point or say even 9 points is not going to work as well as a big bright viewfinder. Link to post Share on other sites More sharing options...
jrc Posted September 21, 2007 Share #367 Posted September 21, 2007 Advertisement (gone after registration) In the time it takes to re-compose the bird will have moved so the eye is no longer in the plane of focus. On the bird photos, what lens are you using? How far are you from the birds? Are these wild birds? On that last shot, it looks like the depth of field is only a couple of inches. Is it a super-fast long telephoto used up close? Just curious. JC Link to post Share on other sites More sharing options...
telyt Posted September 21, 2007 Share #368 Posted September 21, 2007 On the bird photos, what lens are you using? How far are you from the birds? Are these wild birds? On that last shot, it looks like the depth of field is only a couple of inches. Is it a super-fast long telephoto used up close? Just curious. JC John, these photos are of wild birds. I have a few photos of captive raptors and I make a point of stating that they're captives. The pheasant photo was made with the 280 f/4 APO and Leicaflex SL2 on a tripod in a blind. Exposure was 1/60 sec @ f/4 on K200 and this was near the lens' minimum focus distance. The magpie photo posted previously in this thread was also from a blind in my back yard with a Novoflex 400mm f/5.6 T-Noflexar on a tripod (and R8/DMR). The magpie photo is a composite of two pictures. The primary photo of the magpie has almost no space on the left beyond the wing so I took a slice from the previous photo (with bad posture, these birds fidget a lot!) to add space on the left. 1/250 sec @ f/5.6, ISO 400, no more than 2 or 2.5 meters away. Link to post Share on other sites More sharing options...
jrc Posted September 21, 2007 Share #369 Posted September 21, 2007 Ah. I see the problem. Took me a minute to work it out. JC Link to post Share on other sites More sharing options...
hankg Posted September 21, 2007 Share #370 Posted September 21, 2007 Suppose you want to take a photo of a group of people, and you have all of them line up in front of your camera – in a straight line that is perpendicular to the optical axis. If you focus on some person in the middle, everyone else’s image should be just as sharp, right? But then, those at the extreme left or right are farther away from the camera than someone in the middle is. If you focus on the middle person the plane of the sensor and the plane of focus/line of people being parallel everyone lined up in the plane of focus will be in focus baring lens abberations. If you turn the camera to point at the person on the end of the line and focus -the distance between the 2 planes will be greater so if you recompose by turning back to point at the center person your image will be out of focus. For focus and recompose you have to move the camera perfectly parallel to the focus point maintaining the same distance between the 2 planes. If you turn to recompose you will lose focus. Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/31046-is-r10-or-a-brand-new-digital-r-coming/?do=findComment&comment=359126'>More sharing options...
sdai Posted September 21, 2007 Share #371 Posted September 21, 2007 What I'm working towards in my posts here, is to point out that we all want the next R to enable users to focus accurately. AF with only a center point or say even 9 points is not going to work as well as a big bright viewfinder. While I agree with you for the most part, Eric ... I'm not expecting to see a way-too-many AF points system in the "R10". In fact, even if it's still pure manual focus, I'd probably still take it. Making a 11, 45 or 51 points AF sensor isn't really that hard ... many vendors can do it if you hand them the spec. it's about the software program (algorithm) and fast processor driving the system precisely in a speedy manner. Canon introduced the 45 point AF system with the EOS 3 in 1997, Nikon then spent 10 years just to play a catch up. Link to post Share on other sites More sharing options...
andybarton Posted September 21, 2007 Share #372 Posted September 21, 2007 What firmware is the R10 going to ship with? Just wondering... Link to post Share on other sites More sharing options...
cmb_ Posted September 21, 2007 Share #373 Posted September 21, 2007 Andy - v1.3 from the DMR. Link to post Share on other sites More sharing options...
sdai Posted September 21, 2007 Share #374 Posted September 21, 2007 What firmware is the R10 going to ship with? Wow ... this is the very first time I see a moderator trolling his own forum. Link to post Share on other sites More sharing options...
andybarton Posted September 21, 2007 Share #375 Posted September 21, 2007 Fine with me. That one works great Link to post Share on other sites More sharing options...
EH21 Posted September 22, 2007 Share #376 Posted September 22, 2007 Guys, There's a rumor that R10 prototypes are being tested - was posted to the LUG list. I haven't read all the posts only scanned the digest - but the rumor states that the new 22 mega pix camera has AF and a kodak sensor that is no longer 24x36 but squarer. Of course this is most likely all just rumor but that does sound promising. Eric Link to post Share on other sites More sharing options...
sdai Posted September 22, 2007 Share #377 Posted September 22, 2007 There's a rumor that R10 prototypes are being tested - was posted to the LUG list. I haven't read all the posts only scanned the digest - but the rumor states that the new 22 mega pix camera has AF and a kodak sensor that is no longer 24x36 but squarer. Of course this is most likely all just rumor but that does sound promising. This doesn't make sense ... Eric. Then I'd rather go for a H3D II 22MP version (heck, the 31MP isn't much more expensive), same first class glass, auto focus, 645, 22 MP Kodak sensor ... in the mean time I can keep my R lenses for a 1Ds. Actually, I don't even believe larger than 24x36mm sensor will happen ... then the mount size and register distance will all change, no way to fit into a 5D size body ... probably hard to fit into a R9 size body too. All these R lenses become paperweight ... why call it R10 then? get a fancy new name ... something like F1. Link to post Share on other sites More sharing options...
sdai Posted September 22, 2007 Share #378 Posted September 22, 2007 Never mind ... I actually found that post from the Chris guy, you can guarantee it's 100% BS. LOL Link to post Share on other sites More sharing options...
EH21 Posted September 22, 2007 Share #379 Posted September 22, 2007 deleted Link to post Share on other sites More sharing options...
EH21 Posted September 22, 2007 Share #380 Posted September 22, 2007 This doesn't make sense ... Eric. Then I'd rather go for a H3D II 22MP version (heck, the 31MP isn't much more expensive), same first class glass, auto focus, 645, 22 MP Kodak sensor ... in the mean time I can keep my R lenses for a 1Ds. Actually, I don't even believe larger than 24x36mm sensor will happen ... then the mount size and register distance will all change, no way to fit into a 5D size body ... probably hard to fit into a R9 size body too. All these R lenses become paperweight ... why call it R10 then? get a fancy new name ... something like F1. The rumor is most likely BS but you are wrong about having to change mount and register distance. I think a square or close to square format makes better use of the existing lenses. If you are tossing out film then you also toss out the format. Basically you can use any sensor shape that fits in the image circle of the lens. I'm guessing that we'll see less than 22mp mainly because I think most of the currently available 22mp sensors are physically too big and squishing 22mpix into a smaller area would make the sencel sizes to small forfeiting DR and such which I hope Leica will not do. Link to post Share on other sites More sharing options...
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