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About Demonperformer

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    Main Sequence

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    51-ish N; 1-ish W
  1. Demonperformer

    Venus - Oct 19

    7 days before IC is very good. Do you use any sort of colour filter to enhance the contrast of the planet to the sky (I'm told a deep red filter can help)? I too would have thought that Merky being further from the Sun would have been easier. But I guess that, even at this point, Venus is still a great deal brighter (and bigger) than Mercury.
  2. Nicely captured, Luke. I too prefer the first animation. The fact that everything (bar one object) is moving in the latter one makes it difficult (IMO) to make sense of what is actually going on. Great rotation data.
  3. Demonperformer

    Reduced by £100 - Trutek motorised 8x1.25" filter wheel

    Just found that FLO do a 8x1.25" electronic filter wheel for under £300, so who's going to pay £315 for a second hand one? Clearly not the savvy membership of SGL. Therefore, price is reduced by £100 to £215 including signed delivery. PM me if interested. Thanks.
  4. Demonperformer

    PHD2 saying star wont move enought?

    Yes, hot pixel was my first thought. How many stars are you getting on the screen? Does the number/brightness increase when you increase the exposure time?
  5. Demonperformer

    There is life beyond Saturn!

    This is a problem of your own making, Avani. Your shots of the other planets are always so full of detail that "blue blob" just doesn't cut it. We expect more from you Seriously, that is more than I ever managed with Neptune and I am sure images to your usual impressive standard will follow in the coming days/weeks.
  6. Demonperformer

    80D + lens + pillows + bits + moon..

    Nice one. Many would have kept the window shut and waited for the bits. And just think how easy* it is all going to be once you have a mount to put the camera on. * "easy" is a relative term!
  7. Demonperformer

    Had enough

    Been there. If you sell in the throes of frustration you will probably end up regretting it. At the very least, allow yourself time to get a bit of perspective. As regards your issues, approach them methodically and don't try to solve everything in one go. Remember: what's hard by the yard is a cinch by the inch. Now, let us help: What's the first problem?
  8. Demonperformer

    Upgrade to a new mount, any suggestions?

    gentle reminder that all posts should be in english
  9. Demonperformer

    Upgrade to a new mount, any suggestions?

    Start by getting a copy of Making Every Photon Count from FLO. That will enable you to put your purchases in context.
  10. Demonperformer

    NGC7000 SHO + LRGB stars

    REALLY happy? So you should be. Looking forward to the full image when the second pane is done.
  11. Demonperformer

    Motion of telescope on a wedge

    I think a key point to remember is that OP has stated he has an 8SE. Having owned both a 6SE and an 8SE, I would say that the mount is barely capable of AP, with the exception of SS, and that is when the centre of gravity is firmly over the tripod. A wedge moves that centre of gravity to one side and that is bound to make the entire setup less stable. If OP were planning on making a wedge, at little cost, it might be worth a try, but these wedges are quite expensive. OK, not as much as would be needed for a suitable EQ mount, but I still say that this £300 would be better put towards a decent EQ mount. Other mounts may work well with wedges, but this one would not - certainly not for long exposures - and if you are only taking short exposures (and I have taken some deep sky images with this scope using 5s exposures with a cmos camera) just use AZ and crop the final image.
  12. Demonperformer

    One for any electronics experts

    Thanks, Neil, that makes sense. I'm thinking now the 12v one suggested by John will be better as I will save myself the cost of a resistor, the space it would occupy and one solder connection.
  13. Demonperformer

    One for any electronics experts

    Ah, reading a bit further down (why didn't I do that in the first place?) I see that it does. Nice one,John. Thanks.
  14. Demonperformer

    One for any electronics experts

    Well, 24p including VAT, but I'm not going to throw the rattle out of the pram over that. So would that mean that I would not need to include a resistor at all - just attach it directly to the end of the uv strip?
  15. Demonperformer

    One for any electronics experts

    Trying to use the information provided previously to determine the best value for the resistor to go with the red LED. Now my power supply is 12v, as this is what is required by the uv strip. The LED I am considering has the following specs: * Forward voltage = 2.25v * Reverse voltage = 5v * Power dissipation = 120mW * DC forward current = 25mA * Peak forward current = 120mA So, if my understanding of the formulae provided on p1 of this thread is correct, I need to drop the voltage from 12v to 2.25v, which is 9.75v. I then need to divide this by the current, for which I have two values: 25mA or 120mA. If I use 25mA I get 9.75/0.025 = 390 ohms and if I use 120mA I get 9.75/0.12 = 81.25 ohms. Both of these are considerably smaller than the 2200 ohms (or more) of recent recommendations. Now if a higher resistence just means that the LED shines less brightly, that is not a problem for me. The red LED serves no purpose other than to confirm that power is flowing through the circuit, so as long as it is visible I'm OK with it. However, 2200 is between 5.6 & 27 times my calculated figures, which strikes me as a bit excessive. I have no doubt that the problem is with my understanding/calculations, not the advice I have been given, so can anyone explain where I am going wrong? Thanks.

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