• 5 Posts
  • 97 Comments
Joined 2 years ago
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Cake day: June 15th, 2023

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  • I have a question for you that I’ve not been able to get answer to by normal googling or asking the GPTs.

    I need to focus light from cinema projectors using camera lenses. As you might be aware, projectors may use lamp or LED as their primary light source. The former used more wattage for producing same lumens of light.

    My question is: if I choose two projectors of each type that give out same lumens of light and I focus all of it with my lens, will one of them heat up my lens more than the other? I’m other words I’m just talking about the heat perception of light of equal intensity from the two sources and not how much heat is generated in creating them, if that makes any sense.

    Thanks!


  • There exist maps derived from satellite images called Land Use Land Cover maps that categorise each pixel into predefined classes like built up, forest, water, roads etc. Granted that these days semantic segmentation is used to generate such maps but traditional image processing and digitization has always been used traditionally. There is no AI involved in using them for the purpose I mentioned though. Gaming engines like unity have built in tools as well as add-ons like Gaia that have cool procedural generation features. Using such maps in conjunction could help in creating realistic and familiar worlds and this blender tool gives me much hope.


  • I would like it to be possible to give some hints to the model by providing maps showing where roads, buildings, vegetation should be and let it work its magic. Maybe take it further by procedurally generating buildings based on their footprints and building type, like hospitals , schools etc, as identified in maps. That way we can have racing sims in the roads we are familiar with. And much more…




  • The typical home routers don’t support more than 20-25 simultaneous connections last i checked. I’m sure there must be professional devices that allow thousands of connections like they use in public wifi spots but I’m also sure they would be much pricier.

    At this point, it is just a pursuit for understanding how these things work and if what I want can actually be made possible as alternative use case of WiFi, especially given how ubiquitous it is.

    Thank you for indulging me nonetheless.


  • I’m honoured that you took the time to type all this out but it looks like I’ve failed yet again at conveying what I meant to ask and I’ll try to rephrase:

    What you have been explaining is broadcasting when all devices are connected to the same network. I want to understand if it is possible to use WiFi just like a radio to broadcast data, without actually connecting. A device can transmit/broadcast, say, a video over the EM waves using some kind of modulation like they do in FM. The receiving devices, like our phones, already have hardware to receive these waves and process it to extract the information. Like I said, it already happens where the SSID of the WiFi transmitter/router is seen by all devices without actually connecting.

    And before you say anything, yes I’m aware that it is a very small amount of data being ‘transmitted’ at a very low bitrate. But what is the limiting factor? Why can’t much more data be transmitted this way?

    I’m really sorry if there is a silly answer to this as I’m sure there must be. But, like I said, i could never find it in my searches.

    Thanks and cheers!



  • I’ve wondered for a long time if it is possible to use WiFi as broadcast/multicast? I mean, i understand that it won’t work out of the box, but if one was to write code from ground up (ie different TCP protocol) can it be made possible to, say, transmit video lecture from one WiFi router and for multiple mobile phones to receive and view it without individually being connected to the network. Kind of like how everyone is able to view the SSID of the WiFi node without being connected.

    Or is it a hardware level problem that I can’t wrap my head around. I have wanted to understand this for a long time but I don’t have a background in this subject and don’t know the right questions to ask. Even the LLM based search tools have not been of much help.







  • I am not sure if this will pique your interest but I find kinetic sand tables really fascinating. Sisyphus came up with it first and there have been a number of open source implementations in due course. One way is to implement it using a scara arm mechanism but they have the problem of load weight in the case of long arms.

    I came across this design that rethinks the design using an elegant rack and pinion arm but still needs a belt that may go out of calibration over time. This looks to be improved further using [two, concentric rings] (https://frew.io/work/sisyphish) but this design is not available to explore/copy.

    I have no idea about 3D designing, but I would love to create a table one day: something that will not need constant adjustment. If you get around to taking this up, I would love to see what design improvements you can come up with.