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About tashley

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    Erfahrener Benutzer

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  1. Maybe the crosshairs are a sort of marketing gimmick to give the impression of extreme precision, but in fact work just like a box does? Like a volume knob that goes to 11?
  2. Jaap, according to RawDigger it is 6016 by 4016 so not significant enough to to account for most of X... As to the second part of the question I can't answer because my SL is long gone and I didn't have any adaptors to try other lenses - sorry!
  3. Crikey this is complicated! I keep on thinking I must be missing something. Can we agree that in the second of my C1 screen grabs above, the pixel data in the grayed out area of the frame isn't making it into the DNG? If so, let's call that number of discarded pixels "X" From the original 24mp captured, X is discarded. 24-X<24 surely? So whenever any of the raw processing programs tells us is that 24 is the total number of mp in the finished image, represented by the area which is not grayed out, it has to have gone from 24-X (which is less than 24) all the way back to 24
  4. I can't answer that for sure but I'd have a strongish guess that the lens is actually a bit wider than 24mm so after the crop and corrections you're getting a 24mm FOV. I seem to remember someone had discovered that on the Q.
  5. OK, let's try to put this to bed - especially since we all seem to be largely agreeing as to the facts, and can decide the importance of the implications of those facts as individuals! @ Scott, I agree that the C1 rendition with distortion corrections off is very similar to the RawDigger rendition - but it isn't quite the same. For example, it is rendering the file as 6000x4000 rather than 6016 x 4016. I have no idea what else it might or might not be doing, but that's precisely why RawDigger is so useful - because you know it isn't doing anything: it merely gives you the sensor readout an
  6. Scott, with apologies for appearing contradictory, none of that works (if I am correct in my thinking). Firstly, C1 is a RAW developer and is not showing you the actual sensor data, however much you 'turn off'. You really do need Raw Digger to do that. Secondly, extrapolation is interpolation is up-resing by another name: it is making information where there was none, but differentially across the image field. And crudely, too, since with corrections set to off, any complex field information that Leica is including in the DNG is not being used. I suspect that Leica's corrections use a
  7. Nope, that wasn't the specific point of this exercise though it would have been of additional interest.
  8. I have just been looking at DPReview which has some raw files available for download from the A7RII and Gmaster 24-70 F2.8 and I've poked around under the hood of a RAW file and compared it to the JPEG. It seems that the correction in that case is losing about 0.41% at 24mm and F5.6 compared to my estimate of 26% for the Leica. HOWEVER that might well be due to some pre-cooking of the RAW in camera. Which, if it is the case, is more opaque still than the Leica way of doing it.
  9. I'm not sure how much that will tell you Scott. I don't know how familiar you are with RAWDigger but it gives you the 'raw' raw file and lets you analyse it. It does nothing else other than allow a TIFF export if you have the pro version. It's the purest way I know of looking at what actually comes off a sensor though of course it can't undo pre-cooking in camera. C1 (with which I'm pretty familiar) 'does more' to the file - for example even with all corrections turned off it still shows the pixel dimensions as 6000 x 4000. In other words even if you turn off everything you can turn off,
  10. Sure, one could make it any size merely by up-resing. The question is, if you correct the distortion in the raw RAW file to the same degree as Leica's profile tells Lightroom to achieve and then crop the image so no white borders or black corners are showing, what pixel dimensions do you get without then doing the upresing step? I still think it's about 19mp.
  11. Interesting Scott, thanks! I saved as much as I could in order to match the DNG, not to save as much as I could - on the basis that Leica would be saving as much as it could - but clearly the simple linear distortion correction in LR can't go as far as a correction profile which is bespoke to the lens. IMHO even with the wind in the fairest direction the file is unlikely to be more than 20mp at most and I suspect not even that. Take a look at the files I linked above if you have a moment and see what you think, I;d be very interested in a second opinion!
  12. Jared, you voice many of my thoughts and questions? Does it often matter? No. Did I think that the point of such a large and design was to minimize these sorts of compromises? I guess I sort of assumed so. Most importantly, what's the factual background of the MTF? Ps yes, this was ar 24mm and f5.6
  13. You are absolutely correct. However I wager that at least some members here will be surprised by the quantum. We can disagree as to how much it does or doesn't matter but more information is good, right?
  14. I don't honestly think I'm missing your point: I'm talking about what is versus what appears to be, rather than what might otherwise have been. We all make our own choices on these matters as to where we want the compromises to lie and from memory the Q, which I like, has a compromise which I am more easily able to accept at about effective 21 point something mp resolution. I totally get where you're coming from but I do think that 26% is quite a lot and that 19mp is quite a lot less than 24mp, and that one has to do quite a bit of work to understand exactly what compromise one is accepti
  15. Yes the distortion is stretching and extrapolating some areas of the image more than others. But load those three images into a viewer and flip between them and you will see that a lot of cropping is going on regardless of the pixel stretching. Of course, if one area of the image is stretched on average less than others, then by logic, other areas will be being stretched by more. That means that some areas are in effect up-resed by more than 26% assuming that I am correct. In any event, when shot at the wide end the SL appears to be an ~19mp crop-sensored camera with some areas of the frame be
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