IkarusJohn Posted August 10, 2015 Share #161 Posted August 10, 2015 Advertisement (gone after registration) What a load of nonsense. I prefer the idea of a means of accurately focusing. Link to post Share on other sites More sharing options...
Advertisement Posted August 10, 2015 Posted August 10, 2015 Hi IkarusJohn, Take a look here Does the Q Portend the Death of the M?. I'm sure you'll find what you were looking for!
lct Posted August 10, 2015 Share #162 Posted August 10, 2015 [...] What's the problem with focusing and recomposing? With a shallow depth of field and the relatively unforgiving nature of digital as opposed to film, if you focus and then rotate, contrary to what Jaap says, there is a good chance the subject will be out of focus. [...] And a much better chance that it will be in focus unless your favorite sport is shooting difficult lenses like 135/3.4, 90/2, 75/1.4 or 50/0.95 in rangefinder mode at full aperture. Needs a bit of practice though. Link to post Share on other sites More sharing options...
jaapv Posted August 10, 2015 Share #163 Posted August 10, 2015 What a load of nonsense. I prefer the idea of a means of accurately focusing. Glad you picked up on that. It was an expansion of your post.My point is that focus-recompose is a guesstimate. Link to post Share on other sites More sharing options...
AndreasAM Posted August 10, 2015 Share #164 Posted August 10, 2015 Leica did more than speculating in this patent from 2012: http://www.google.com/patents/DE102012009975A1?cl=en 00120001.png How much I like to go with you on this one, the patent doesn't say anything on if it will or how to simulate a digital focus patch. It only states that the information coming from the optoelectronic rangefinder (and possible the addition of phase detection on the sensor) wil give directions on exact focusing or wil feed an AF-lens when focusing. The way in which this direction is projected in the viewfinder is left open in the patent. I think it is possible to simulate a focus patch digitally, but we will have to see how inventive Leica can be in this case. We are so used to the mechanical RF and its focus patch , that starting afresh and invent a different and better we is not that easy. Link to post Share on other sites More sharing options...
CheshireCat Posted August 10, 2015 Share #165 Posted August 10, 2015 With a shallow depth of field and the relatively unforgiving nature of digital as opposed to film, if you focus and then rotate, contrary to what Jaap says, there is a good chance the subject will be out of focus Digital vs film has nothing to do with that. The problem with focus and recompose is lenses with a complex focus field. For lenses with virtually flat focus field, like many teles, focus and recompose usually works great. Link to post Share on other sites More sharing options...
pop Posted August 10, 2015 Share #166 Posted August 10, 2015 Digital vs film has nothing to do with that. The problem with focus and recompose is lenses with a complex focus field. For lenses with virtually flat focus field, like many teles, focus and recompose usually works great. Recomposing teles would work fine and if it's only on account of the small angle you will turn the tele. Link to post Share on other sites More sharing options...
mjh Posted August 10, 2015 Share #167 Posted August 10, 2015 Advertisement (gone after registration) The error introduced with focus-and-recompose has nothing to do with curvature of field. The worst case is limited by the angle of view and thus it is much less of a problem with long focal lengths. Link to post Share on other sites More sharing options...
CheshireCat Posted August 10, 2015 Share #168 Posted August 10, 2015 The error introduced with focus-and-recompose has nothing to do with curvature of field. The worst case is limited by the angle of view and thus it is much less of a problem with long focal lengths. Actually, real life is a bit more complicated than your oversimplification, and the shape of the focus field is the most important factor when you focus and recompose. If you do the math, an outward bending focus field will be much worse, and an inward bending field may actually help compensating the error. The problem with many bright wides is that the focus field has a complex shape (35 FLE is a nice example), so it is very difficult to predict what happens when you focus and recompose. Link to post Share on other sites More sharing options...
AlanJW Posted August 10, 2015 Share #169 Posted August 10, 2015 One would think reading this thread that focus and recompose does not work at all, and could never work due to all of the variables decribed. Yet, I have found it works fairly well including so called "problem" lenses like the 35FLE. Of course, I rarely try to focus on something at the edge of the final frame and I do not always shoot wide open, so perhaps that explains why I am not failing at it. I do it all the time with 35 and 50 (both Summilux and Summicron) with success. Also, my very wide is a WATE that is f/4 and I suspect there is enough DOF there to make focus and recompose work, assuming it is necessary at all at f/4. Link to post Share on other sites More sharing options...
mjh Posted August 10, 2015 Share #170 Posted August 10, 2015 If you do the math, an outward bending focus field will be much worse, and an inward bending field may actually help compensating the error. Exactly. Curvature of field is an entirely different issue that may either exacerbate or compensate the purely geometrical focus-and-recompose error. The main point about the focus-and-recompose error is that it is a factor even when curvature of field is perfectly corrected for. Link to post Share on other sites More sharing options...
IkarusJohn Posted August 10, 2015 Share #171 Posted August 10, 2015 "oversimplification" is a bit rude, don't you think? I agree that a shifting plane of best focus does complicate things more than a bit; but the fundamental point that if you focus in the centre of the image and recompose (unless you shift your feet) you can expect the subject to move out of focus (within the tolerances of depth of field and field curvature, the latter being unpredictable, as you observe) remains true. It doesn't matter if you stand on your head, rotate about the centre of the lens or the focal plane of your camera - you are adding back focus to whatever your lens is doing. Now, obviously, the effect will be greater or smaller depending on the focal length of the lens and its other "features", but the trigonometry has remained unchanged since Pythagorus. Being able to move the focusing point is a useful, and I would say basic start. Granted, whether or not it is actually in focus is another issue you can only really be sure of if the confirmation is through the lens, but providing an accurate start, and removing guesstimate, is surely a good thing. Happy to guess exposure with my M-A and M3, but that is another thing entirely. I can adjust exposure in post processing (provided the detail is still there). I can't improve the focus. Link to post Share on other sites More sharing options...
i-Leica Posted August 10, 2015 Share #172 Posted August 10, 2015 ...but the M's optical viewfinder seems to have a strong following that's unlikely to diminish. so why everybody want a better EVF on "M240" camera? Link to post Share on other sites More sharing options...
Peter Kilmister Posted August 10, 2015 Share #173 Posted August 10, 2015 If you wish to take a picture using a non-standard lens, for example using an OEM macro tube. Then an EVF or LV are the only ways to achieve the desired focus. LV is OK unless in strong back light. EVF is perfect in any light and is adjustable for eyesight irregularity. I like EVF when required, although I prefer the RF for any number of reasons when used with standard lenses. Link to post Share on other sites More sharing options...
lct Posted August 10, 2015 Share #174 Posted August 10, 2015 One would think reading this thread that focus and recompose does not work at all, and could never work due to all of the variables decribed. Yet, I have found it works fairly well including so called "problem" lenses like the 35FLE. [...] +1. Most if not all M users have been doing this since the last century so if it did not work they (we) would know it already. We don't shoot brick walls and rulers often enough at f/1.4 though perhaps... Link to post Share on other sites More sharing options...
jaapv Posted August 10, 2015 Share #175 Posted August 10, 2015 so why everybody want a better EVF on "M240" camera? I don’t... Link to post Share on other sites More sharing options...
IkarusJohn Posted August 10, 2015 Share #176 Posted August 10, 2015 +1. Most if not all M users have been doing this since the last century so if it did not work they (we) would know it already. We don't shoot brick walls and rulers often enough at f/1.4 though perhaps... Well, if we're going to include last century, why has the M changed at all since the M3 ... some of the best pictures taken with a Leica camera were taken using that camera, or the III. Are you saying the problem is non-existent? or just not that big a problem in really life? I would agree with the latter, but I don't really see that as justification for persisting with a fixed focusing point if it can be resolved. I don't think it can with the M, so I see no point in asking for what cannot be realistically provided; but for a new camera system, I would like to see this - it is something I used to use often, and to me it is a shortcoming inherent in the M camera. so why everybody want a better EVF on "M240" camera? I don't either. I actually don't want EvF on the M camera at all, and if I had an M(240) I would resist using one because I like the optical rangefinder on the M camera. But, this thread is about the effect of the Q camera on the M. My point is that the Q camera should have little impact on the M (other than attracting more buyers to the Leica brand). The new system camera (if there actually is one) will hopefully have a significant impact on the M camera by providing a complete digital system, without the compromises that crept into the M(240). Now, many say there aren't any compromises, and the M(240) is perfect. That's fine, but for future M cameras, I would prefer an M that stuck with what it traditionally has been good at - manual focus M lenses in the range 18mm to 135mm with an optical rangefinder. The new system could then provide the things that many digital photographers really want - AF lenses with the ability to use M, R and other lenses using adapters, WiFi, multiple metering, multiple AF, movable focus confirmation, live view, EVF (built in), video etc etc. I have the M cameras the way I want them, and I would like to think that Leica will continue to make them in what some call "the purist" form. I would also be interested in the new digital system, if it took the best of current technology and presented it in the integrated and simplified user interface that Leica is so good at (and frankly, Sony is crap at) - all with excellent IQ. I must confess I really don't understand the new opto-electronic rangefinder or what its impact on the M camera would be. The intelligence available so far seems to be that a new full frame digital system is to be released - that is something other than a further iteration of the M camera. Doubtless that will come too, but that is a different issue. Cheers John Link to post Share on other sites More sharing options...
pico Posted August 10, 2015 Share #177 Posted August 10, 2015 Exactly. Curvature of field is an entirely different issue that may either exacerbate or compensate the purely geometrical focus-and-recompose error. The main point about the focus-and-recompose error is that it is a factor even when curvature of field is perfectly corrected for. We can espouse all we like about the nuances of re-composure, but Leica's customer base could probably care less. They want a super high quality build and are certainly less fussy about the nuances. Make it black enamel, brass body for heft, and technical enough so that they look good on their yacht, promenade, street, conference. The target luxury Leica customer is not in this forum. Link to post Share on other sites More sharing options...
IkarusJohn Posted August 10, 2015 Share #178 Posted August 10, 2015 We can espouse all we like about the nuances of re-composure, but Leica's customer base could probably care less... Yep, pages and pages of the benefits of black paint versus black chrome, and brassing are far more critical here than improving on the accuracy of focusing, it seems. They couldn't care less ... Link to post Share on other sites More sharing options...
lct Posted August 10, 2015 Share #179 Posted August 10, 2015 Are you saying the problem is non-existent? or just not that big a problem in really life? I would agree with the latter, but I don't really see that as justification for persisting with a fixed focusing point if it can be resolved. [...] For me there is simply no problem to resolve actually. I have the choice with other cameras but moving the focus point takes too much time for me so i never do it otherwise than on tripods personally and i would not like my Leicas to become complicated like that. Just my two cents. Link to post Share on other sites More sharing options...
pico Posted August 10, 2015 Share #180 Posted August 10, 2015 Ultimately Leica must move beyond the optical viewfinder. I think we all know that in our hearts. Looking back to the introduction of the M8, I am deeply impressed at how Leica has moved forward through the historical resistance, sludge, backwater of their heritage. Leica must be employing some true heavy-weight engineers we know nothing of. Perhaps we will learn of them. After all, lenses are not everything, especially now that the awesomely ugly Karbe editions have been released. Link to post Share on other sites More sharing options...
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