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Everything posted by 12dstring

  1. That's a nice meteorite, a very well thought out gift. The Canyon Diablo is great because you can show people the big hole it left Make sure to keep iron ones somewhere that won't get humid, rust isn't good. And it is indeed a very slippery slope if you get into collecting...
  2. That sounds interesting, there's a few people here wanting to give exoplanet transits a go. We're setting up one of the telescopes to work robotically at the moment and lots of the requests are for photometry. Snap! I got the Chris Kitchin prize in 2010, I have no reason to believe someone didn't get it last year.. The actual imaging was about an hour (including a dash inside to get my coffee). I used batch processing in Registax and AviStack so just let it run overnight both times. With my mosaics I prefer to use big overlaps (~1/2 frame) and stitch them together manually. It took 2-3 hours
  3. Looks great so far Helen, I'm looking forward to the full size version too. If you're looking for somewhere to upload it to, I use Windows Live SkyDrive - Online document storage and file sharing for mine, you can upload up to 100mb files. If they're really big then Zoom.it is also handy for displaying large images so they don't slow down people's browsers.
  4. Thanks guys My previous mosaics were done in the early hours of the morning when the seeing usually calms down, but I've never know it so good at 6pm. There were student practicals on Tuesday and Thursday using the same setup to image the moon and Jupiter, the seeing was good for both of them but perhaps a little better on Weds. I've uploaded one of the videos so you can see how it looked: Unfortunately Bob retired a year ago, we still miss him. But it's in good hands, and lots of students this year so the observatory is being used plenty. What project did you do there?
  5. Look fantastic Mike Always a pain missing a tiny bit out. It's not as easy as just copying from an earlier image as the libration and exact phase will almost always be different, but you've done a great job there - I can't see where the cloned bit is.
  6. ...well half of one. I like moon mosaics. They're fairly easy to do with modest equipment; I can get 16 megapixels on the quarter moon with my 6" newt and £10 webcam, and the moment of relief when you get to processing and realise you have no gaps is fantastic That said, I had to take the opportunity to use a bit more aperture, so took this on Wednesday between 17:30 and 18:30 from the University of Hertfordshire observatory, Bayfordbury, Herts. Lumenera Skynyx 2-1 at prime focus of an LX200 14". 37 videos, 500 frames of 50ms exposure at 1280x1024, best 200 of each used in final stack. Seeing
  7. PL-2303 drivers are found here: Welcome to Prolific
  8. I've not taken any astro pictures with it yet since starting these mods, but the temperature control electronics will take a while so I expect I will before that's done. Just having the copper as a passive heatsink ought to keep the noise down by drawing away the heat produced. The 1100D should be fine for amp-glow. I believe all models after the 350D efectively have an amp off circuit included.
  9. One things that soon becomes apparent after cooling is how intrusive the amp-glow becomes. As with modified webcams the glow is caused by an amplifier on the sensor that heats up, and the glow is causes gets worse with exposure length but doesn't respond to cooling. Luckily as with webcams it can be eliminated the same way, by reducing the voltage supplied to the sensor whilst it's actually imaging, before returning it to the full voltage during readout. All inspiration for my modifications came from Mike Kudenov (http://glogg.jupiter-io.net/300d/amp_off/amp-off.asp) and Cas Wilders (http://m
  10. I had a quick look at the Herts allsky camera for last night, there's some kind of glare on this frame: http://star.herts.ac.uk/allsky/imageget.php?jde=2455941.40694&c=1 just above Ursa Major (if you blink between the previous image). Obviously hard to say, but I wonder if this is the fireball you saw. The time and direction match.
  11. I've decided to dedicate my 350D to astrophotography, so have been making a few changes. The IR filter replacement was done a few years ago, and a few months ago I added in an amp-off modification to remove the lower-right amp glow. The next step is peltier TEC cooling. I took piccies of the internals of the amp-off and cooling as I was doing it but won't be able to get to them until next weekend, will post later... But for now here's how the outside enclosure looks at the moment: It's fitted into an IP65 box, and I'll plug up all the holes I make so I keep the humidity low enough to prevent
  12. I got a quick image of it last night at around 23:30 2x300s with an 16" LX200 at Bayfordbury Observatory, Herts. The nearby moon led to some interesting gradients. Magnitude v=13.7 The next few nights are looking fairly good so will continue to monitor.
  13. Hi Bob, It was picked up by an allsky camera in the Isle of Wight: http://star.herts.ac.uk/allsky/imageget.php?jde=2455939.26151&c=3 and in Hertfordshire (low to the SW): http://star.herts.ac.uk/allsky/imageget.php?jde=2455939.26183&c=1 I've heard another visual report from near Aylesbury, a blue/white object with a yellow trail. Sadly didn't see it myself.
  14. To follow the pictures you'll need: 1 x 2N3904 transistor (although really any of Maplin's "Low Power LF NPN Transistors TO92 Case" will do) 2 x 10k resistors - 1/4W size (or Metal Film 0.6W from Maplin's are the same size) The mosfet circuit doesn't have any advantages over the transistor one other than only needing 1 resistor, but I suspect people would be more likely to have NPN transistors lying around.
  15. I've not had any problems with mine, however unmodified it will be more susceptible to noise so if you have a noisy power supply or nearby cables for example you'd be less immune to that noise and communication errors would be more likely. If you've got a soldering iron then I'd recommend the mod even if it works without, as it's pretty simple and allows you to extend the cable if needed (10m as Glider says). It just pushes it over the £4 mark.. but only by a few pennies
  16. Recommended mod to bring the signal output up to 5v Either of these circuits will do, to help with noise immunity and longer cable lengths. My implementation: Top And fitted back in the case:
  17. It's a sound point. The simplest method is probably the mosfet+2 resistors as shown here: Bi-Directional Level Shifter – HUSSTECH The 2N7000 is a TO-92 part so should fit in the case snugly, and the two unconnected pads along the bottom next to Tx are 3.3v and 5v if I remember correctly so should be easy to tap into them. I've only got surface mount mosfets at the moment, which I know isn't everyone's cup of tea, so I've ordered a few 2N7000s and will post back with pictures when they arrive. Another way to help with any noise issues is to shorten the cable, and extend if needed on the USB sid
  18. I originally planned to have a little 3.3v-5v level shifter circuit as well, but I left it out after I tried without and it worked. I've had mine running over the past month with no issues. I'll open up my mount tomorrow and check the specs for the PIC, if it would prefer more than 3.3v then there's enough room inside the converter to add a few components to bump up the output to 5v.
  19. I know I've been quiet for a while, finishing my degree and now living the dream working as an observatory technician now. It's no excuse for not posting more though... I was aiming for a neat all-USB approach for my setup. One USB cable to my SPC900NC guider, and my DSLR is going to be modified to include a USB hub with an 'auxilary port' on the side of the camera box. The EQDir can then plug into the camera and I'll only need 2 USB cables going between the camera and mount (plus power). The converter casing can be pulled apart with the aid of a thin flatheaded screwdriver, and can be pushed
  20. Take one PL-2303 USB-serial cable (e.g. USB to UART (TTL) Cable module PL2303 Converter | eBay) - £2.99 One 2m RJ45 ethernet cable (e.g. 2m BLACK RJ45 CAT5 PATCH ETHERNET NETWORK CABLE LEAD | eBay) - £0.99 Remove one end of the ethernet cable and strip back, check wiring colours. The USB serial converter has a small circuit inside: As a side note, the little PCBs are great for mods that need a serial interface such as webcam long exposure mods or DSLR shutter cables. The DTR and RTS signals required for them are indicated below (labeled A and B on the PCB). Note the chip is a 3.3v part with
  21. For anyone not receiving their promotional emails, there is also the discount code MORG10 to get 10% off over the next 2 days. Unfortunately it can't be used with the already discounted unflashed webcam, but seems to work with the pre-flashed bundle and webcam adapter.
  22. After unplugging from the board, grip the cable from the inside where it comes through the housing with some pliers (there's two notches on either side) and turn it 90 degrees. You can then pull it out easily. Dave
  23. Thanks for the little promotion Craig I wrote it using lots of input and suggestions from fellow astronomers, the moon size comparing feature was somebody else's suggestion. I'm always up for improving or trying to add an extra feature if anyone can think of anything they might find useful
  24. I was trying to post yesterday and it wouldn't let me, as of this morning the last post was by someone at around 1pm so I assume it's a problem for everyone. I tried logging out and back in again this morning but it won't let me log back in... so I'm stuck now
  25. Found the problem! (I'm an idiot) When drawing out my schematic, I managed to swap over two wires to the switch. When in normal exposure mode it was fine, as the two wires were connected normally, but when in LX mode the wrong wire was being connected to the +5V rail. Thanks for getting me to look deeper for my problem anyway!
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