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Many comments below seem to be from persons “interested” in optics, but who cannot design simple optical systems using first order optics, and who have never se
by aj7 4y ago
Many comments below seem to be from persons “interested” in optics, but who cannot design simple optical systems using first order optics, and who have never set up simple ray tracing with basic components or 2 x 2 matrices.
Just as in electronic design with SPICE, in sizing components and choosing materials using FEA, or in fluency with ONE computer language, advanced tools are useless if you haven’t put in the basic study in the field, and have never used these components in the lab.
No program can turn you into a practitioner by itself.
- world2vec 4y agoCould a complete amateur learn how to make a cheap DIY telescope lens in their own garage?
- jiggawatts 4y agoYes! While I haven’t done so myself, I looked into home-made telescopes as a way of getting much larger apertures on a budget. There is a whole group of hobbyists making primary mirrors up 80cm diameter for an order of magnitude lower cost than any off-the-shelf telescope with the same dimensions. Of course this takes hundreds of hours of work (fun!) and weeks of waiting while the glass is sent off to be mirror coated.
- analog31 4y agoDefinitely. People have made DIY scopes for at least a century. There's still a lot of old literature around. Among optical systems, a basic telescope is one of the least complex.
- mastax 4y agoCheck out Huygens Optics on YouTube. Lots of practical advise and tutorials.
- aj7 4y agoYes there are many books. It’s the motivation.
- joshvm 4y agoI'm not sure if it will necessarily be cheap, maybe cheaper than an off the shelf mirror of equivalent size. This is what John Dobson (of the Dobsonian) is famous for. However you still need to do stuff like coat the primary mirror once it's polished and you can't easily do that at home. See https://youtu.be/snz7JJlSZvw https://youtu.be/snz7JJlSZvw
- chantepierre 4y agoSilvering mirrors is coming back in fashion, either with the old recipe à la Jean Texereau / How to make a telescope, or with a spray silvering process. This week I silvered my last mirror with spray silvering, which was quite economical and convenient. I used 1.6g of silver nitrate for a 200mm mirror.
- poulpy123 4y agoIf by chance you read french, there is the reference for french amateur telescope builders here http://www.astrosurf.com/texereau/ http://www.astrosurf.com/texereau/
- dekhn 4y agoyes: a simple scope is really just two lenses in the right positions with some wrapping around it. I sat around with lenses of known focal lengths, the wikipedia page for keplerian telescope, and just sort of 3d printed enclosures until everything was the right distance from each other.
- mastax 4y agoI like visualizing things. Tools like geometers sketchpad were useful when I was learning trigonometry, even though the equations weren't very hard. The basic optical equations aren't very hard, but equations aren't sufficient for developing an intuition (for me!). Sticking a bunch of lenses on an optical breadboard and shining light through them was very enlightening. Playing around in SketchUp won't make you into a mechanical engineer. If there were an equivalent for optics it wouldn't make you into an optical engineer. But that doesn't mean it wouldn't be very useful for it's tiny market.
- RobotToaster 4y agoThe few introductory guides I've found seem to dive straight into some very dense maths. There's also a difference between having an intuitive understanding of a subject and a mathematical one. You can have the former and know how to use tools, eg, using a fourier transform is different to doing one manually.
- dekhn 4y agoactually I just learned SPICE in about a day and it completely revolutionized how I make circuits. Same for optical tools- a little time spent with a visual tool (like this one) can greatly enhance my ability to work creatively and make useful things in reasonable amounts of time.
- aj7 4y agoI too learned a lot from Spice. But I was familiar with linear systems, circuit theory, op amps, and had a decent lab with components, a soldering iron, a scope, a signal generator, and a meter. For me, you have to build stuff to really understand. Imagine my surprise when I discovered that a simple 7805 regulator’s output voltage wasn’t 5 V with no load!