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  2. Clipping is process of cutting off certain values due to various factors. It is usually consequence of limited range of numbers that we work with. For example one can have "clipped stars" and bright parts of the image. This happens if target is bright enough (like some stars tend to be) and exposure is long enough. Maybe best analogy would be trying to pour water in buckets. All buckets can hold 5 liters of water and you try to pour 3, 6 and 8 liters in respective buckets. You will end up with 3L of water in first, but 5L and 5L in second and third - as they can only hold so much water. Values of 6 and 8 liters were cut off because of bucket size and you ended up with 5L in each. Because clipping cuts off values to same value - you end up with "white" surface instead of features in that place in the image. You can also clip black levels in histogram manipulation - it will create uniform dark surface without details - just like you selected area and did "bucket fill" tool in PS. Whenever you have any sort of cut off - you are changing information in image and loosing details / features. That is why this is bad (but sometimes can be used to good effect - like minimizing background noise and smoothing background out). HTH
  3. I mounted up the C9.25 this afternoon only to discover when I took the lens cap off that about a quarter of the corrector lens was covered by water stains on the inside Not much choice but to take the corrector out, then. Eeek! So, I marked the orientation of the parts as I took them off so I could put them back the same way. Fiddling the outer retaining ring past the pins that are presumably there to prevent it falling out was actually the most awkward part. I then discovered that the secondary was also pretty filthy so got the blower on that and did the needful on the corrector with Baader OW fluid. It now looks much healthier. Interestingly, the edge of the corrector had both a "V" mark etched into the glass and a pen arrow drawn on, about 40mm apart. It wasn't obvious that these two marks lined up with anything on the OTA though, so I ignored them and just reassembled it using my own marks. All in all it was far less stressful than I expected. I don't want to do it again, but I shall feel less worried about it if I have to. Now I just need to check the collimation... James
  4. One Sky-Watcher Heritage 100P. Customer Return Very minor signs of use. Complete with full manufacturer's warranty. £94.00 £74.00 (saving £20.00)
  5. Are you sure that it is in contradiction to expansion, could it just be peculiar motion of that galaxy because of local mass arrangement / gravitational pull? Any link on the source of info?
  6. Out of curiosity, what do you think is wrong with your old ones? Here is what I would do - for solar and lunar I would use preferably mono camera. If you value full disc shots without doing mosaics - then you need sufficiently large chip. For regular planetary imaging - I prefer color camera. Your 178c is good for much of this. Solar is tricky because it involves Ha, and mono camera is better there, but 178c is sensitive in Ha with all pixels - some more, and some less. Using flats will even things out, and although it is not the best solution it will certainly work. Having said all of the above, what do you hope to gain by getting a new camera? How much improvement? In mono segment, way to go would be ASI290 or alike camera - due to low read noise. However 178 mono sensor is not trailing much behind, and I wonder if it makes sense to get one since you already have 178c. 290 will almost cover full disk with Lunt so you will need at least two panels for full disk image with it. Same goes for Lunar. For planetary, I think the best option at the moment is 385 based camera due to lowest read noise and other characteristics that are more than fine.
  7. I've looked at the screenshots of BYE and APT and found them to be too complex for my needs, filling the display with unwanted tools and info. I use Canon Utilities which takes up little space on the screen. Good luck with your next session Michael
  8. Can someone explain in relativity simple terms to u defat and what is meant when clipping is referred to in images? I read being mentioned quite frequently, but even after being in the AP game for a couple of years, I don’t fully understand what it refers to! Rgds Aidan
  9. If you use sky safari with the SynScan App you can download loads of double star designations into it.
  10. hello everyone i have the sky watcher esprit 120 and the heq6r pro mount and im considering to buy autoguider package to my setup and wanted to aky you if this package is good? and recommended? some reviews... ZWO 60mm ASI120MM Guide system (ZWO – ASI120MM-s) also im considering the Orion Magnificent Mini Deluxe AutoGuider Package... which is better? thank you very much!
  11. Today
  12. Yes, I got it last time I was at astro camp. That's my camping obsy in the foreground with Davey T's kit behind. The Earth's shadow is the grey area below the pink belt of Venus, apparently named after the Goddess rather than the planet. Quote from the internet: The belt of Venus is an atmospheric phenomenon just before sunrise or after sunset, red sunlight can be seen in the upper atmosphere but a dark shadow of the Earth is on the horizon.
  13. Guys - time to choose a new camera. I have been using QHY cameras for some time but have decided to think again. What is the view on alternatives for lunar, solar and planetary? The only constraints will be USB3 obviously and price as I don’t want to spend a fortune (circa 500). The solar is Ha through a Lunt 50 and I’m partial to full disk images. Scopes can be seen below with the exception of my Swift 77mm refractor which has been very good on the moon. Thanks in advance Keith
  14. I had forgotten about those multi NB filters for OSC cameras never having used one. But as you say it does take longer. Carole
  15. One Sky-Watcher AZ GTi WiFi Alt-Az Mount Only. Customer Return Checked A-OK. Complete and with full manufacturer's warranty. £210.00 £179.00 (saving £31.00)
  16. Astronomers have determined that Messier 90, a lovely Spiral in Virgo, which contains many galaxies,is heading for a collision with our Milky Way galaxy, and there is no doubting it. As M90 is about 60 million light years away, it sure ain't gonna happen next week, but happen it will they say. The movement contradicts the expansion theory of Red Shift, but M90 is definitely Blue Shifted. This is only part of the report, there is more, but the basic info. Is above. Ron.
  17. Hi Happy, the cable wasn’t tight at all.
  18. It’s a brilliant little bit of kit. Shame about the name.
  19. And the wasteful packaging award goes to Amazon who shipped these two little adapters in a seperate box to the other things that arrived today.
  20. Power tank and case arrived today. The Floureon 12,000mah power tank will keep the Quark going for quite a while. The “Tactical Waterproof Mobile Bag Military Phone Holder” ,as the manufacturer calls it, has loads of straps and a hook to attach it to just about anything. Will replace the usb cable with a coiled one to keep it neater.
  21. Olly thanks for the idea but the subs are too saturated for the core. But I have located some shorter subs in another folder.
  22. Power tank and a phone holder to put it in. Lots of straps and hooks on the case to attach it to the tripod.
  23. Try Amazon.... https://www.amazon.co.uk/Converter-Adjustable-Step-Down-1-25V-36V-Raspberry/dp/B01DF3JUPY/ref=sr_1_9?crid=WRKENHLSWXOJ&keywords=buck+converter&qid=1558877274&s=gateway&sprefix=buck+con%2Caps%2C744&sr=8-9 Alan
  24. Lovely. What camera and mount are you using to get these shots? Mark
  25. Cross my palm with a bottle of Prosecco and I'll be happy to provide the future vision of your choice!
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