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Chrissie

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Chrissie last won the day on December 22 2018

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About Chrissie

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    Switzerland

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  1. I like the top one best, because the object is sharp and against a motion-blurred background, which really conveys the impression of speed. Very well done! The center one is obviously a slow fly-by, as you can tell by the downward deflected flaps. ;-) It's also nice and in focus, however against an empty background. Unlike the "birds in flight" category, with a human pilot you have the advantage that you can pre-arrange such slow fly-bys, which gives you a beforehand knowledge of where and when it's going to happen, which helps in avoiding camera shake.
  2. Been there. It sounds really tempting, getting an 83x zoom which extends to 2000mm equivalent, for less than US$ 500,-. Don't expect any miracles, though. I recently bought a Nikon Coolpix P900 for my wife. We tested it during a one day hike in the alps, and found the image quality to be exceptionally poor, at the very long end. So much so, that we eventually decided to sell it (at a loss, of course, with a shutter count of only around 50 or so.). Maybe i am spoiled from the image quality of a full frame, but in my view there is no point in taking pictures which you hate to look at. My wife now has a Sony RX100, in the "mark Va" variant. For the very same reason as above I opted against the "mark VI" variant, which has a longer reach, but a poorer image quality. P.S.: see this for a "caveat" description of the Nikon Coolpix 900: I don't see how having to use a tripod would work well enough when trying to capture small, fast flying objects.
  3. ... is not dependent on the lens alone. The body (sensor, processor) have a big impact on recognizing, whether an image is sharp or not, and generating the appropriate commands to the lens to move glass in the proper direction. The former is obviously a function of the body itself, while only the latter depends on the lens. Also, when you're talking about fast moving flying objects, the risk of motion blur from body/lense shake is always present, in addition to motion blur from the fast movement of the object itself. So you will need good in-body stabilization, preferably complimented with in-lens stabilization, too. When you go for long-reach lenses, the rule-of-thumb tells you to use an exposure time of 1/4th of the reach, or faster. For a 400mm lens that would be 1/1600th or faster. To avoid malinvestment or disappointment, I'd recommend to rent and try the lens of choice for a weekend, before you decide to buy it.
  4. Chrissie

    NEW Sony a9 adopter

    Nice introduction. Welcome and enjoy your new toy. Good choice.
  5. Have a look at this comparison in the lens database of dxomark. They seem to be on par in the "sharpness" subcategory.
  6. Chrissie

    Solar Imaging

    I regret to hear that. But, provided you can still drive around, or have someone who can take you somewhere, it's always worthwile to get to a position as high up as possible for any kind of celestial observations. Because the lowest parts of the atmosphere tend to be the "thickest", haziest, foggiest and most polluted. It gets better the higher you go. For night sky views (stars) and/or shots it's advisable to select a place as far away from any artificial light source, like human dwellings. Good luck with your recovery.
  7. Chrissie

    Solar Imaging

    Living in a valley implies, you are surrounded by mountains. Have you ever tried to climb one of those mountains and shoot from there? Note my tagline ;-)
  8. Chrissie

    Sony Zeiss 55mm f1.8

    Ian, I've temporarily uploaded some sample pictures at full resolution and maximum jpeg quality, taken with this lens on my a9, onto my flickr account. I will delete those after a week or so. It's a great lens in absolute terms, and also great value for the money, too. Did you see it's rating on dxomark?
  9. This limitation doesn't exist, if the a7riii user manual can be trusted: If you run into an ISO limitation regardless, maybe you have set an "Auto ISO range" limitation. See the "Hint" on this page for details.
  10. @JCC: thanks for your interest, and I'll try to deliver: If something is unbalanced about an axis of rotation, you need a torque to offset this imbalance. A torque in the physical meaning is defined as the product of force times leverage. (A force being generated by a mass times gravitational acceleration, btw.). its SI unit is [Nm]. Suppose you have an imbalance which requires a countering torque of 10Nm, then you could create that countering torque by applying a force of 10N at a distance of 1m from the axis of rotation, or by applying a force of 1N at a distance of 10m, or by applying a force of 100N at a distance of 0.1m. All these combinations will generate the same countering torque of 10 Nm. That's the static part. When determining the moment of inertia, you have to compute the mass times the (distance from the rotational axis squared). See this for the math involved. Lets consider the above case of an imbalance of 10Nm. If you counter that by a weight of 100N at a distance of 0.1m, the moment of inertia = 100N * 0.1m * 0.1m = 1N*m^^2. If you counter that by a weight of 10N at a distance of 1m, the moment of inertia = 10N * 1m * 1m = 10N*m^^2. If you counter that by a weight of 1N at a distance of 10m, the moment of inertia = 1N * 10m * 10m = 100N*m^^2. This is the reason, why flywheels concentrate their mass at the perimeter, connected by mere spokes to the axis of rotation. Source: https://dqbasmyouzti2.cloudfront.net/assets/content/cache/made/content/images/articles/flywheel_721_420_80_s_c1.jpg Or consider a tightrope artist, using a long pole with little weights at its end, to keep his balance. Source: https://upload.wikimedia.org/wikipedia/commons/c/c0/Samuel_Dixon_Niagara.jpg
  11. Adding counterweights obviously adds weight, which probably sounds trivial, but there's more to it. You will achieve a static balance that way. But you're putting a drag on the dynamic behavior of the gimbal, because you're increasing the total moment of inertia, which tries to resist any rotational acceleration. I would always prefer to statically balance my setup by shifting the existing gear into the position necessary for balance, rather than maintaining a position and adding counterweights. That said: if you can't avoid adding a counterweight at all, it's preferable to add a bigger weight close to the axis of rotation, rather than adding a smaller weight far away from the axis o rotation. Again for dynamic reasons. I can elaborate on that if there's interest.
  12. Well thanks, @Lagrimon, for this information. But I still wonder about the cause-effect relationship between silent shooting and the loss of color-depth resolution.
  13. Very interesting! Do you have a source for that information? Because I wonder how turning off the sound would cause the color depth to decrease.
  14. Chrissie

    EVF Shot Review

    This is a standard function for most Sony cameras. For an a7riii, see this.
  15. If you're located somewhere in the EU, you may want to try the following hardware comparison site: https://geizhals.de/?cat=monlcd19wide&sort=bew You'll find some 70+ criteria to narrow down your search, along with an individual comparison option of the 3 to 5 "finalists", a selection of possible dealers with customer satisfaction history, user comments, test results etc.. Even if you're not from the EU, this might help you in the decision which one you'll want to go for. Where to get it from is of course still up to you.
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