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leszekp last won the day on September 29

leszekp had the most liked content!

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About leszekp

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    Archaeology of the American Southwest and West.
  1. leszekp

    The size of dome

    For lithics, I use the normals mode, then manipulate the RGB channels individually for maximum contrast. Convert to grayscale, do some more advanced contrast work (clarity/CLAHE), sharpen it up, and you get a fantastic image of the flake scars on the stone tool, better than any hand drawing.
  2. leszekp

    An alternative for controlling 3W leds

    Running the 3W LEDs continuously is definitely a bad idea when there's no heat sink. The solder melting point is less than 200C. They only need to be on long enough to take your photo, which shouldn't be more than a few seconds. While many of these are rated up to 1A, the usual nominal operating current is 700mA, at which current level they will stay quite a bit cooler. Intensity is a bit lower, and the exposure time will be slightly longer, but it's not going to be a huge different (a few tenths of a second).
  3. leszekp

    An alternative for controlling 3W leds

    I had the same thought a few years ago, but decided that it didn't make sense. You're fitting a curve to the (primarily) Lambertian lighting scattering at every point based on the lighting angle. If you change the lighting intensity with angle, you'll skew the lighting curve to fit to those higher intensities, which will introduce errors. Shadows are areas where the main light source is blocked, so any signal from those areas is a result of scattered light within the dome, which doesn't really offer you any useful signal for curve fitting.
  4. leszekp

    An alternative for controlling 3W leds

    You might give this site a look (not that I'm biased or anything): https://hackaday.io/project/11951-affordable-reflectance-transformation-imaging-dome
  5. leszekp

    The size of dome

    This is a useful rule-of-thumb, but I've found that you can sometimes stretch this a bit. I just did RTI on a 7" long Mayan lithic blade inside a dome with a 9" light to object distance, and got a more than acceptable photo out of it (with a bit of work in Photoshop).
  6. leszekp

    Embedding Rti viewer into Wordpress

    You can embed it in a WP page using an iframe tag. Example: <iframe src="http://swvirtualmuseum.nau.edu/wp/RTI/Powell_Watch_2.html" width="600" height="640" frameborder="0" allowfullscreen="allowfullscreen"></iframe> View the result on this page: http://swvirtualmuseum.nau.edu/wp/index.php/national-parks/grand-canyon-national-park/rti-gallery/
  7. leszekp

    Difficulty launching RTI Builder

    I had the same issue with Windows Defender on one of my computers. You'll need to set an exception/exclusion for this file: https://support.microsoft.com/en-us/help/4028485/windows-10-add-an-exclusion-to-windows-defender-antivirus
  8. I've been using a Yuneec Typhoon H hexacopter (12 MP fixed focus camera) for recording archaeological sites, and have gotten excellent results. I expect that the Inspire 2 would do at least as well, if not better. For high accuracy, you will need to have ground control points measured with high accuracy (Total station, RTKGPS, or equivalent).
  9. leszekp

    Coin imaging

    Take a photograph of the sphere,and load it into Photoshop. Use the Ruler tool to measure the diameter in pixels (you may need to right-click on the ruler and select "Pixels" as the scale).
  10. leszekp

    Outdoor Photogrammetry: Issues and Questions

    You might try shooting at a slightly higher ISO (up to 400); you'll get faster shutter speeds to reduce the blur, and the added noise is likely to be small. You might also try processing the dense cloud at UltraHigh to get better resolution for your models. Using a camera pole can get you higher camera elevations, for more angles. With a faster shutter, you can try holding the camera pole obliquely to get good angles above the scene without disturbing the area.
  11. Got an email today from Ashira at the Met. Videos of the presentations from last March's RTI symposium are now online. https://www.metmuseum.org/about-the-met/conservation-and-scientific-research/projects/rti-symposium
  12. leszekp

    Problems processing PTM vs HSH?

    This is the kind of error that pops up if the proper input variables have not been passed to the PTMfitter program. You might try running RTIBuilder as an admin (right-click on the program icon, and choose Run as Administrator); this has fixed similar problems for me.
  13. leszekp

    Bogus virus warning

    Idiotically, you can't set exclusions in Defender.
  14. leszekp

    Bogus virus warning

    I have Windows Defender as my antivirus on my laptop, and today it decided that RTIBuilder is a dangerous virus and deleted it from my computer. Heuristic virus diagnoses are very annoying. If you have Windows Defender, be on the lookout for this. Main computer has BitDefender, which has no problem with RTIBuilder; will probably disable Windows Defender and install BitDefender to resolve this problem.
  15. leszekp

    Unsuccessful download for RTIBuilder Win32

    Do you have Java installed on your system? RTIBuilder needs Java to run.