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Astigmatism

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Astigmatism last won the day on April 11

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  1. Forgot to mention another thing. Mine does not work if I plug the USB cord into a USB hub. It only works if I plug the cord into one of the USB ports on my computer itself (an iMac). This surprises me because I think there's a hub built into the computer itself, which is how the computer has multiple USB ports in the first place. I think it was somebody here that suggested I try that -- sorry I don't remember who!
  2. Thanks for answering my question! About this one item -- why is it better to do this with the camera on? Just curious.
  3. I do read the fine manual. A text search on locking sensor turned nothing up.
  4. What is most ironic about this is that there must be many of us here that would be interested in significant ads about the products we're discussing. I would be. I normally hate ads, but relevant ones here would actually be somewhat welcome. What are the recent new Fuji product announcements? Is anybody offering a sale? How about 3rd party products? I mean, I actually want to spend money, more or less.
  5. I don't think I have your answer, but it's worth trying. It's been a few days, are you still struggling with this? I've used Acquire (on an iMac) and an X-T4 (also an X-T5 and an X-T30 ii) and it worked, at least as far as backing up. No error messages, and a computer file with stuff in it. I understand you get an error message when you attempt to restore the camera from a backup, but, does it look to you like the backup phase is working? I mean, do you get a saved file and no error messages? Do you have any other Fuji cameras, and does it work for them? I have had problems getting Acquire to detect the camera. I did all manner of playing around with starting the software, plugging in the camera, and powering the camera on, in various orders (including what the instructions say). I always got it to work eventually, but it took lots of playing some times. Lately it fires right up. Somebody here commented on this difficulty and the security obstacles in the computer. Are you getting a connection easily, or after trying things, or not at all? Does Acquire show your camera model and the few settings it displays correctly?
  6. I tried a series of photos to show how vignetting works as the lens aperture is varied, for the Laowa fisheye. I took outdoor shots low to the ground on a tripod, as I adjusted the aperture ring through each labeled f/ stop detent. Shutter speed was automatic. I pasted a middle slice through the circular image for each aperture into a single slide, then labeled and marked that to post here. The aperture is indicated off the right end of each slice. A red line marks the horizontal center. The slices all contain the same pixel locations from the photos and were treated identically. The photos themselves were all done identically except for the manual aperture settings and the automatic shutter speeds compensating for them. You can see the ends of the slices are darkened for larger apertures but it improves as aperture is reduced. I kind of figure that at f/8 and narrower I'm unlikely to notice the vignetting in most pictures. Of course, fisheyes are easy to get enough light into, even handheld in dim conditions.
  7. I haven't tried either the PerGear or the Rokinon. They're full frame fisheyes, which I've never been interested in. But if anybody else has tried them, it'd be great to get more information here.
  8. I like circular fisheyes and would love to see Fuji offer one for X mount. But until they do, the 3 available ones I know of are made by 7 Artisans, Laowa (Venus), and Meike (or Voking). I have all three (including one labeled Meike which Amazon says is no longer available, but what looks like the same lens is now available with the Voking brand). It's debatable whether I'm more of a photographer or a collector, but I do love lenses. I recently tried to compare the 3 fisheyes carefully. I think the whole point of a circular fisheye is to capture as much angle as possible, so I measured how big an angle each lens captures. I set up a blinking light at a great distance, and mounted each fisheye on my camera on a stable surveying tripod with a graduated azimuth head. The light and the lens were at the same height and the camera was leveled. I measured how big an angle I could swing each lens by, such that the blinking light was barely visible in the viewfinder. All the lenses covered more angle than they claimed, but they exceeded their claims by different margins. The claimed angles and the observed angles are ranked the same way. 7 Artisans wins this contest, but only by 4.5 degrees, while Meike trails behind by 18.5 degrees which is a way bigger difference. Here's a table of the focal lengths, aperture ranges, claimed and observed coverage angles, and the number of elements and groups in the construction. Fisheye f Aper Claimed Observed Elem Groups 7 Artisans 4 mm f/2.8-16 225 227.5 10 8 Laowa 4 mm f/2.8-16 210 223.0 7 6 Meike 6.5 mm f/2-22 190 204.5 6 5 I also took pictures with each lens at its most open and closed aperture settings. I mounted the camera on a stout tripod using an ARCA-like clamping system so I could reproduce the aim used with each lens. I shot downward toward a gravel bank, nice and contrasty, with the sun pretty nearly aligned behind the camera on axis. There were lots of tree branches against the sky around the edge of the image, and I blew up these parts of the images to compare them. These are manual focus lenses and I used focus peaking at widest aperture to assist focusing. Note that lenses like these have more depth of field than focusing range for their moderate and small apertures; that is, you officially don't have to bother focusing them, because everything is within the depth of field. All the same, I did focus them in their open aperture state. I had ISO at 250 and let the camera choose shutter speed. I used the self timer and the electronic shutter to minimize any shaking of the camera on the tripod. All the shutter speeds wound up being more than fast enough to freeze any motion in this still life. There's a huge difference between wide open and stopped down. The wide open images all lose a great deal of brightness further from the center of the picture. This is vastly improved in the pictures that are stopped down. My picture here is a slice of each, without any doctoring, moved and sized to match each other as well as I could by eye. The lens maker is noted in red on each slice. Notice you can pick out many details in the branches that are common to all photos. The Laowa does the best by far. The 7 Artisans is not as sharp, and has a great deal of lateral color aberration. The Meike is much blurrier still. Oddly, I keep finding the Meike doesn't look as saturated to me, though I have no idea how a lens can lower saturation. Also, while you have to look pretty close to find a few little edge area details that are captured by the 7 Artisans and missed by the Laowa, both of them have way better coverage than the Meike. So I'm concluding it's the Laowa I'll use most, though it's possible in some extreme situation I might use the 7 Artisans to get the widest possible angle. Don't know what I'd use the Meike for.
  9. This lens is very nice! But I don't like the narrow metal hood. With my clumsy hands it's very difficult to mount and dismount the ordinary lens cap. I think they realized this is awkward and difficult, because they also provide a rubber cap that fits around the end of the metal hood; however this keeps falling off. Is there an alternate hood, more in the style of the other Fuji plastic hoods, that works acceptably? It'd have to not cause any vignetting, but it's not so important that it blocks all the extraneous light. I used to shoot without any hoods on my lenses, which I know isn't ideal but also isn't unusual -- any stray light blocked is an improvement over that! Thanks!
  10. Lock the sensor? How do you do that?
  11. It's been a while, are you still dealing with this? The camera has to know what the focal length of the lens is. It's using accelerometers to measure shaking and then shifting the sensor (and elements in the lens if it's an OIS lens) to compensate. The longer the focal length, the further things have to shift. Does this lens tell the camera what focal length it's set for? Forgive me, I don't have any experience with putting non-Fuji zooms on the X-T5, but I'm guessing not. You can't just say it's an 18-300, either, the camera needs to know the focal length you've set it to. You have to use MOUNT ADAPTOR SETTING to do this.
  12. I was shooting with the XF 30 macro on an X-T5 just the day before yesterday, flowers outdoors and in a greenhouse. I had nice sharp images. A hyacinth in direct sunlight at f/8, 1/250 s, ISO 250 is gorgeous all the way to the edge of the image. Also an old gate latch with very nice red oxidation where the black paint wore through, very striking when I blow the image up.
  13. What jerryy said. Couple more ideas: putting color filters in front of the lens can help. There are "straw" filters that look very pale yellow, which knock out the shortest blue wavelengths without changing most subjective colors much. Maybe somebody also makes a filter that knocks out the longest reds, also without changing colors much. And, if you can play a little with composition -- I mean, if your subject lends itself to this -- you can orient the edges with the biggest brightness contrast to be radial in your image, rather than circumferential. Chromatic aberration only happens radially with respect to the optical axis (e.g. the photo center if it's not cropped. I *think* there are many optical systems that are achromatic, specifically being corrected for two widely spaced wavelengths, that will tend to have green versus purple (red + blue) fringes. Picture a graph of the effective focal length as a function of wavelength, and these systems will be a smile or a frown. For some purposes (such as astrophotography) you can get much fancier and more costly optical systems that are apochromatic, corrected for three wavelengths, whose graph will slope up-down-up or down-up-down. Going beyond that, systems based entirely on mirrors have no chromatic aberration. I guess -- don't know this for sure -- that camera lenses using both mirrors and refraction, catadioptric lenses, could have less chromatic aberration than lenses without mirrors. These are generally fixed focal length, fixed aperture lenses. There are some 3rd party ones available for Fuji X, though I don't remember seeing any that are autofocus.
  14. Not even manual focus on the FX 14 mm f/2.8 R, with the clutch? You engage manual focus by sliding the focus ring rearward, which reveals a distance scale that you can read against classic DOF markings for different apertures. I have this lens, and just tried turning the focus ring with the lens not mounted on the camera. Looking into the rear of the lens, I see something shifting in re the aperture stop as seen through the glass. Not sure but I think this lens design might be a dozen years old. Sliding the focus ring forward disables it and makes the lens autofocus. I'm not disagreeing, I'm just curious. I have wondered what's going on in there.
  15. Some questions re: "Important notice for consumers processing FUJIFILM digital camera files using macOS", part of which says: "While the current firmware versions allow these X and GFX series cameras to internally write and store 9,999 frames to a single folder, it has been observed that if more than 4,000 files are written in-camera to a single folder on an SDXC card and directly accessed using macOS the firmware incompatibility creates two potential scenarios: (1) Some files on the memory card may become inaccessible if the card has been connected to the computer through an internal or external memory card reader and directly accessed using macOS. [...]" This refers to SDXC cards, meaning 32 GB to 2 TB capacity (SDHC cards hold less than 32 GB and SDUC cards hold more than 2 TB). Questions: 1) Is this still a problem, using a new X-T5? 2) Does using MacOS Photos to import images from a card (my typical use) count as "directly accessed using macOS" or do they only mean using MacOS Finder to access the image files? I mean, how is "directly accessed" defined in this context? 3) Would SDUC cards fix this issue? I'm not even sure they're a thing -- not finding them on Amazon. Haven't tried the experiment, which could take quite a while.... If anybody knows, thank you very much!
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