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pete_l

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About pete_l

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    Brown Dwarf

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    http://www.under-a-dark-sky.com

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    Benamaurel, Spain 37N
  1. Something I use from time to time on Windows computers is AutoIt. This allows you (with some difficulty, admittedly) to automate Windows GUI operations such as moving the mouse, clicking on buttons, entering text, etc. https://www.autoitscript.com/site/autoit/
  2. pete_l

    One for any electronics experts

    Yes, that would seem to be precisely what you are expected to do. If you don't want to cut away the plastic, just melt it off with your soldering iron.
  3. I can't think of any dedicated astro camera that has an anti-aliasing filter installed. If there was either a need for them or an advantage to having one, they would be part of the product.
  4. pete_l

    One for any electronics experts

    First off, about the wavelength. We can assume that 365nm is a typo and that the clue is in the part number viz, NCSU275T-U385 as the device is one of a family of similar devices - tuned for different wavelengths. Now, about care and feeding. You will almost certainly be supplying this device through a fixed voltage supply (e.g. 5 Volts). The device spec states a forward voltage drop of 3.6 V (page 2). So the remaining 1.4 Volts must be "lost" in the current limiting resistor you will put in series with the device. The datasheet tells us the maximum current the device can handle is 700mA. So to get that current flow, you should invoke Ohm's law V = I * R, rearranged to calculate resistance, So R = V / I. Inserting values, V is the 1.4 Volts we wish to drop. I is the 700 mA working current so R = 1.4 divided by 0.7, which is 2 Ohms. Be aware, this is the maximum current the device can handle. There is no requirement to run it at that level. If you wish to work with a lower light intensity (maybe one that isn't quite so eyeball-frying) you can reduce the current through the LED by using a larger value resistor. In all cases you should pay attention to power dissipation: when the LED is running at full belt: 700mA dropping 3.6V it will dissipate 3.6 * 0.7 = 2.5 Watts - a significant amount of power. On its own, this would probably burn-out the LED. So it would need to be thermally connected to a largeish heatsink, to keep the device within its working temperature range. Reducing the current through the device also reduces its heat output, meaning a smaller heatsink is needed. But then the resistor has to dissipate more power. P.S. Considering that the light output of this LED is beyond visible range, you might find it helpful to put another LED (e.g. a red, yellow or green one) in parallel with it and mounted some distance away. That will give you a visual indication of when your sun bed flat-panel is operating. This second LED can be driven at much lower current levels., say 5 mA. So place a 1k resistor in series with it and feed it from the same 5 Volt supply as your U-V LED.
  5. At the risk of starting an argument what would the team suggest as their ideal telescope (no binoculars) for £100, £300 or £600 budgets? Fully working, Straight out of the box.
  6. Be aware that when those multi-turn pots reach the end of their travel the screw can continue to be turned. Try turning it in the opposite direction. I have used a lot of these. They don't need a load to run at the set voltage. I would suggest removing your LED for the time being and just hooking up your DMM. Another thought: are you sure that the ones you have aren't a fixed output voltage and the pot is there simply to set a current limit, rather than to control the output voltage?
  7. pete_l

    How to effectively drop from 12V DC to 5V?

    Try bitsbox.co.uk they stock them and their p&p charges are honest - even posting to outside the UK https://www.bitsbox.co.uk/index.php?main_page=product_info&cPath=140_171&products_id=3202
  8. pete_l

    Views sought on possible OSC camera option?

    It sounds like you are on the right track, investigating more sensitive cameras. Have you considered some of the new, nearly real-time devices that Mallincam have come up with in the past few months? I don't know of anyone outside the USA/Canada who has managed to buy one, but they do produce some impressive example images. I noted your line "Even using the EQ8 and using an OAG I’m anticipating loosing quite a few subs due to poor guiding." That sounds surprising for an EQ8. Since the goal is to maximise total data-collection time, it sounds like there is an opportunity here!
  9. pete_l

    3D Printers

    I have always considered 3D printers to be novelty items - over-priced and with few practical applications. However, the market does seem to have changed in the past year. The Creality Ender3X is getting good reviews for < £200 and I am now giving it some serious thought. However, I still feel that they are far less useful (and much more hassle) for the average person than all the publicity and promotion would suggest. Without wishing to start a war here's an interesting video:
  10. There are some people who say this, but my personal experience (I started with a GOTO mount) doesn't support that. Just at the most basic level, you learn the constellations because you see where the telescope is pointed! And from that you get to "join the dots" (or stars) and see which ones are near to others, what the patterns actually look like and how far away the major objects are. Since I was living in a light polluted location at the time, this was invaluable as I couldn't visually see many of the stars that are used as starting points for star-hopping. So you will find that with GOTO you will quickly learn the major constellations: Leo, Orion, Cassiopeia etc. You will also discover that many do not look like they appear in star charts - especially when your sky brightness makes a portion of the stars in a constellation invisible. And if you want to do things the hard way you can always turn GOTO off! Though then you should choose a mount that can be slewed manually. If I hadn't got a GOTO to start with, I would have quickly given up due to the sheer frustration of light pollution and spending too much time on rare, clear, nights trying to get my bearings.
  11. pete_l

    Strange Flats

    The "flat filter" I made uses several layers of plain white kitchen roll. Just use enough layers to get the brightness down to the taget level (I used 3). With that over the front of the objective, it is too close for focus so if there is any grain, it doesn't show up.
  12. pete_l

    migration windows to linux

    Indeed. Once you have found that. I would suggest you look on the site's home page : https://stellarmate.com/ The description of the actual function is very well hidden in all the hype, buzz-words and eye-candy.
  13. pete_l

    migration windows to linux

    Yes, the Linux community is its own worst enemy. The good news is that STELLARMATE is a completely packaged hardware and software product. You just buy the box from some outfit in the USA and once it is delivered and you've paid all the excess VAT and import taxes, it is a case of following the instructions. Provided you can decode the jargon that is inherent therein. I've been "doing" software for nigh-on 40 years now, professionally. I have been doing various things with Unix (the precursor to Linux) since the early 1980s. Yet I still have difficulty wading through the publicity material for many products. And that is not down to my lack of technical skills. You would think it would be the simplest thing in the world for every new tech. product to have an introductory line on the home page of their website, right at the top, along the lines of X is a piece of software that runs on .... and is used to ..... But in their enthusiasm or inexperience hardly any amateur entrepreneurs ever think of doing this. It often takes several minutes for the casual visitor to work out whether (as in this case) the "product" is hardware, software, a combination of both or whatever. All I can say is: take whichever route is easiest.
  14. pete_l

    Biggest sensor with 1 and 1/4 filters ??

    An interesting approach and a nice price! On the one hand, my hobby is astrophotography, not fiddling around in the dark trying to get software to talk to hardware. So if this really can do everything without intervention then that is great. On the other hand all that extra complexity is more stuff to go wrong. Decisions, decisions!
  15. pete_l

    Rats!

    Yes, I've had a mouse chew through a low voltage cable. I know it was a mouse because the cable was powered. It turns out that 12V is enough to zap a small furry rodent. There does seem to be something that attracts them to plastic. There is also the issue that as nights draw in, wildlife starts to look for places to over-winter.
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