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Pieter last won the day on June 11

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  1. Here you go, seems like I was wrong on a couple of parameter magnitudes as I did it from memory but the principle for the cause of your banding still stands: Sensor is read in 12 rows at once (not 5): http://blog.kasson.com/the-last-word/sony-a9-electronic-shutter-operation-single-shot/ Mechanical shutter closes at 1/300 sec, the electronic shutter at 1/150 sec: https://blog.kasson.com/the-last-word/how-fast-is-the-sony-a9-electronic-shutter/ As an engineer I'm sure you'll appreciate Jim Kassons crazy elaborate testing and documenting 😉
  2. A full sensor readout takes about 5 ms (1/200 sec) so there's some spare time between shots. Assuming the sensor is read in 800 row pairs, the time between two pairs of rows being read is about 6 ns. Only very fast moving subjects or extremely high frequency artificial light will cause issues with the A9, visible as banding on pixel level. I can see it wasn't shot under artificial light, just saying that this may cause a similar issue (though will look very different).
  3. Based on your shutter speed I presume this was shot with an A9? Your post doesn't say, I was confused a bit by your opening sentence which seemed to refer to an A7Rx photo. I think it has to do with the electronic/rolling shutter of the A9: it reads about 5 rows of pixels at once and then proceeds with the next 5 rows. The wing of the bumblebee will have moved a bit in between the two read sequences, causing the banding you see. Even though your exposure time was 1/16000 sec, reading the entire sensor takes about 1/200 sec. The sensor readout thus takes much longer than the actual exposure time.This also causes banding in extremely high frequency LED-lighting for example. Try the mechanical shutter at 1/8000 sec and see if the banding persists. Perhaps also disable EFCS, tho I doubt this has anything to do with it.
  4. Indeed, on pixel level the noise and motion blur on the 42mp A7RIII images will be much worse than for the hypothetical 12mp A7SIII. But if you downsample the 42mp A7RIII image to 12mp, noise and motion blur per pixel will be very similar to the A7SIII (the noise in the A7RIII image will be much reduced due to averaging the noise over several pixels), with the potential to get a crisp 42mp shot. Upsampling a 12mp images to 42mp doesn't ever get you a crisp image. If your workflow allows for it I therefore don't see a disadvantage in shooting a high mp image as base material. You can always downsample it to get less noise and motion blur on pixel level.
  5. Yes and no. The A7Riii has roughly 30% more pixels horizontally and vertically. For the same print size (say the maximum you could do with your A7iii), sharpness will be equal with both cameras. The A7Riii just has the potential to print 30% larger if you manage to get a sharp picture. Since the pixels are 30% smaller horizontally and vertically on the A7Riii you'll roughly have 30% more motion blur per pixel. To counter this, you'd need a 30% shorter exposure. If you run into the maximum sync speed (1/250 sec for both cameras) indeed the headroom is limited on the A7RIII. But freezing motion blur is not a true or false criterion: it totally depends on the speed of motion you're trying to capture. When always shooting at the maximum sync speed and you reject all pictures with the least bit of motion blur per pixel, indeed the A7iii will get you slightly more keepers. But like I said in my previous post: if you downsample the 42mp pictures to 24mp, both cameras will show the same amount of motion blur. In my opinion this is all false reasoning: might as well get a 12mp A7Siii then when it comes out: this camera will have even larger pixels than the A7iii so much less motion blur per pixel...
  6. I'm not a studio photographer myself but it is true that you'll need a faster shutter speed for tack sharp images (at pixel level) if you have a higher resolution sensor. When printed at the same size however, it shouldn't matter. I guess it would mess up your workflow but if you'd edit a 42mp RAW and downsample it into a 24mp jpeg, you'd end up with similar or higher sharpness than if the original picture were shot at 24mp. In other words, you'd loose nothing by taking a higher mp shot as a starting point.
  7. The reason I didn't provide help on how best to use the lens is because I don't own one (though it is a genuinely remarkable lens, the low light transmission doesn't get me excited for the price). My knowledge of this lens is therefore based on the same information available to you and Deeliciouz (Google, YouTube, etc). I guess you heeded my most important piece of advise, which is to accept the fact that the lens doesn't satisfy your needs. Glad your store had such a generous return policy! I'm sure that you can spend this money on some other lens that will give you much more pleasure in photography. With regards to your lens advise question: the 55 f/1.8 seems like a sensible option as this focal length is a gap in your lens collection. Be aware that it does suffer from significant longitudinal CA, which for me absolutely destroys the fun in having a fast lens with shallow DoF. It is however a very light and compact option at a useful focal length so if you dislike swapping lenses it might work for you. Based on your posts you want a versatile lens with a bright aperture and good image quality. Ever considered an f/2.8 zoom like the Sony 24-70 or Tamron 28-75?
  8. Good advise is always appreciated but you talk too much of stuff you seem to know little about... The two ladies are at totally different distance to the camera so f/1.8 would likely give too thin DoF. Only one of the ladies would have been in focus or you'd have to do a focus stack. Imo the aperture choice was perfect here. If anything, the 100mm GM resembles mostly a 100mm f/4 in terms of subject isolation / amount of background blur. The only way to get good subject isolation with this lens is to have the subject close to the camera and at great distance to the background. Therefore this lens has a fairly close minimum focussing distance (maximum reproduction ratio of 1/4), making it suitable for pseudo-macro shots. It does give exceptionally smoothly blurred backgrounds if done properly, but it doesn't give a lot of 'background blur' in regular portraiture scenario's Such a lens does not exist.
  9. How do you define a 'large image', and in what sense are your images lacking? Do you want a higher megapixel count? Buy an A7Rx-camera instead or learn how to shoot multiple images and merge them into one. Do you want a larger file size? I don't see why anyone would want this save for the neccesary size to ensure high picture quality, but make sure your image quality in camera is set to 'jpeg fine' or 'raw+jpeg'. If you want still larger file sizes, open the jpeg in Photoshop and save it in the highest quality possible. This gains you nothing except a larger file size though. Do you want a larger area covered in your photos? Increase the distance to your subject when taking the photo, buy a wide angle lens or again learn to shoot and merge multiple images. Are the images not large enough when viewing them on your Mac? Enlarge the viewing window or buy a bigger monitor. I'm sure there are still other reasons for one to find his images not large enough...
  10. Glad you took my rather blunt comment in a constructive way: it was ment as such. Like I said in your other thread, the 100mm GM is really a specialty lens and most people who buy it do so after thorough research and for specific purposes. The 100mm GM really is not a general purpose portrait lens and not suited for everyone. Based on your posts I doubt you appreciate it's specific character as well. For a fair assessment of noise performance, try the Sony 100mm wide open versus the Olympus stopped down to f/5.6 and tell us how you appreciate the difference.
  11. Again you fail to grasp the essence of this lens and the technical aspects of photography... Your Oly lens is an f/1.4, the Sony is a T/5.6. That's 4 stops of difference, meaning you can shoot your Oly at iso 320 in the same lighting conditions. Even when taking into account the smaller sensor area, (roughly 2 stops of disadvantage in light gathering for the Oly compared to the Sony) of course it will have better noise performance than your A7iii at iso 5000! Your frustration with this lens is really your own doing. To me the images look pretty darn clean for iso 5000 viewed at 200%... It's really the best one can hope for in a camera at this moment. If you want less iso noise, your 135/1.8 should work wonders.
  12. You're welcome. Should more questions arise I'd be happy to help.
  13. Practice makes perfect and there's a lot to practice with this camera if you come from a dslr. If your previous camera was a Canon or Nikon APS-C, the a6000 should perform very similar in terms of image quality (if not better due to newer sensor). Of course one can always argue about each brands color rendering in jpeg and the autofocus behaviour of a mirrorless camera is quite different from a (d)slr. If your expectations were that the a6000 would perform much better IQ-wise you might be disappointed. By the way, when assessing out of camera jpegs, make sure all lens corrections are turned on in camera. There shouldn't be noticeable distortion then about which you complain.
  14. Something must indeed be wrong as your experience with the a6000 sounds nothing like mine. It is indeed true that for low ISO's, image quality is more dominated by lens performance than sensor performance. Some people argue their new smartphone takes pictures which are just as good as those from a decent camera. When shot at base ISO and printed to a small size that may well be true. It is in worse lighting conditions and with a proper lens attached when your a6000 really shines. The 16-50 is really a convenience lens as it packs so small and light, but it doesn't get the best out of your camera. Regarding the autofocus performance: the a6000 has many different autofocus settings compared to a P&S. Learn to master them and you'll find you have much better control over where you want to focus. Autofocus on the a6000 is plenty fast but imo never assume the camera knows where you want to focus: you decide and tell the camera what to do. Misfocus on stationary subjects is usually user error. To be honest I upgraded my a6000 to an a6500 as I had focus issues on moving subjects with the a6000, especially when the subject was moving towards the camera (I have two small kids that move a lot).
  15. If you're really desperate: does it help to tape off the sensor (e.g with black insulation tape)? I read about some hack to make the sensor less sensitive by taping off half of it.
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