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Joined 1 year ago
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Cake day: October 22nd, 2023

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  • Here is the basic equation explaining the relationship:

    Focal length / Sensor width = Distance to subject / Width of field at subject

    A normal lens for a camera is defined as one whose focal length equals (more or less) the width of the sensor. Often, the width of a sensor is measured from opposite corners. A focal length equal to the sensor width will give you a width of field—at the subject—equal to the distance to the subject. Doubling the focal length halves the width of view, doubling the sensor width doubles the width of view, etc.


  • I did that last Friday. It was a night parade, no sky light, with inadequate street lighting, on a narrow two lane old-time urban street. 50 mm was definitely too long (on full frame) for many of the shots but I managed to place myself at a turn in the road so it wasn’t awful. I exposed for the highlights, which consisted of a multitude of Christmas lights on each float, and a lot of the shadows were indeed rather dark. The lens was a f/1.8, and most of my shots were f/2.2 at rather elevated ISO. My keeper rate was well below what I’m accustomed to. Definitely I’d use a wider lens were I to do this again, like maybe my 28 mm f/2.8, and I’d shoot it wide open.




  • I’ve had fiber installed at two houses this year, and in both they worked with me to get the fiber, the ONT and the Ethernet exactly where I wanted them at no additional charge. At my old house, the fiber came in through the basement in the back, the fiber runs under the joists until it ends up under my office, and they ran Ethernet up to an outlet on the office wall. At the new house, it enters into my basement workshop, on the top shelf of a cabinet, where the ONT is and Ethernet goes to my router. There is plenty of extra fiber coiled above the drop ceiling for relocation.


  • At 2000 square feet one unit might work. If you have brick, stone, or concrete interior walls, then it probably won’t work well.

    Usually I recommend one WiFi access point per thousand square feet per floor, especially with stick frame and plaster construction, although more area per AP is usable if the surrounding WiFi radio environment isn’t too crowded.











  • My place of employment has an 80 Mbps upload / 80 Mbps download fiber optic connection, with approximately 150 users. The network works fine, but the network hardware is good, enterprise-class hardware: Fortigate firewall, Cisco routers, Brocade managed switches, and Extreme Networks WiFi access points.

    Sure, no one is downloading games over the network, although there are a lot of software updates, but they are doing extensive YouTube and Netflix streaming, etc., and our supposedly tiny 80 Mbps connection handles multiple 2K streams without issue, and without lag or hiccups.

    The first most important thing our network does beyond typical consumer hardware is traffic shaping, Quality of Service, and traffic prioritization. There simply isn’t any reason why software updates, downloads, and media streams need to have low latency, but it is critical that interactive processes get high priority. ASUS routers have some of these functions, but a router distribution such as pFSense, OPNsense, or OpenWRT, running on PC hardware will do it better than simple consumer models. Consider the “prosumer” class Omada or UniFi product lines as well.

    Small but frequent critical infrastructure traffic such as DNS and clock synchronization is centralized on the network, so that each and every device is no longer getting that information from over the Internet, but from a local server, and our firewall enforces that, redirecting or blocking attempts to bypass the local server. Many Windows and Google updates are also locally handled by a server, so these updates gets downloaded only once.