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  2. Cge pro is a bad choice for almost anyone today and not really worth 5000. Mostly because getting replacement parts is becoming quite hard. You are essentially risking buying a heavy paper weight.
  3. Self quoting because I now understand the confusion referred to in the posta above. When I wrote "once you crop", I wasn't referring to APS-C vs. Full Frame, but rather that, due to very evident coma, I can't use the full picture of the 50 f1.8, even when stopped down to f4, but need to crop the central part only, thus losing FOV. Due to this, the final framing appears as taken with a longer focal length. Clearly enough, resolution is the one at 50mm. A very evident case is Orion: the whole constellation should fit nicely in the frame, with the nifty-fifty on APS-C. But due to coma, I have to crop part of the image, and finally can't get the whole constellation in a single pic. Fabio
  4. Yesterday
  5. Thats pretty low, not what i would have expected from a fellow amateur, i don't get how someone can stoop that low.
  6. Wonderful disk image there Adam.
  7. A very nice set of prom images there. I am a great admirer of your solar images.
  8. Sorry I should have mentioned 150 PDS.
  9. Hi Marvin, I have a used with a very good working focuser and the upgraded 9 x 50 finder available for sale at £120.00 UK pounds. I you look at astro buy and sell you will see my advert for it. Kind regards, Patrick
  10. Well, it seems to work around my bath and shower :) James
  11. It confused me for some time when I started, too :) I have the impression it's something that comes from "normal" photography. There it seems quite common to talk about focal length of lenses in terms of the field of view you get in combination with the sensor. An APS-C sensor such as is in the more consumer-focused Canon cameras is about 1.6 times smaller than the full frame sensor found in the more "professional" models (I'm being a bit footloose and fancy-free with "consumer" and "professional" here). Which means that the field of view when used with an APS-C sensor is about the same as you'd get with a 1.6x longer focal length lens on a full-frame sensor and in this case 50 x 1.6 = 80. I've seen quite a few photography websites where someone casually writes something along the lines that "because this lens is being used on an APS-C sensor it's actually a focal length of X" where X is 1.6 times the stated focal length of the lens. For standard photography this may be a useful shorthand, but taken literally it is of course not true. The optics of the lens cannot somehow magically change configuration merely because it has been placed in front of a different size sensor. The focal length is what the focal length is. And for astro work where we're generally not that interested in what the field of view is compared to a full-frame camera, but may well be interested in the actual field of view in terms of how much sky fits onto the sensor or how many arcseconds there are per pixel, the stated focal length is always the one to use. James
  12. From left to right - 1. Minix mini-PC - this runs all my imaging and guiding. I remote into it using an iPad via the little white travel router on top 2. Bottom - yes a lithium ion battery for the dew heater 3. On top of the battery is a Lacerta dew heater controller which measures the ambient temperature to regulate my dew heater. I velcro all this to a dovetail which is bolted onto the scope rings...I've since moved to a lighter dovetail, as the one in the picture was unnecessarily heavy. Next stop is to shorten as many of the cables as I can....
  13. but couldnt resist it so i just bought it
  14. I was following the incident when it happened, so I know who posted it and can confirm it was a stolen image and the offender offered to delete the post when found out by the original owner of the image. I must say I am a little surprised to see the offender is still currently posting here online and has not been banned! Maybe a stern warning from the admin was deemed sufficient?
  15. I am a member of a Metal Detecting group where somebody claimed that he had found certain coins but had, in fact, bought them from somebody else. Who knows how the ego works?
  16. Hmm... that's what I thought and it was oozing out everywhere. I wondered if it was actually waterproof.
  17. I don't understand why silicone bathroom sealant wouldn't work. Perhaps not enough to get a really good seal? James
  18. I've had Windows Updates break my Camera in the past too, although for me it was with my Canon DSLR. Windows updates can be rolled back if you want to test this theory.
  19. I'm not sure if I actually understand what had happened. I do understand that someone posted others image as their own, but where did it happen? On Facebook? Here on SGL? Are both persons members here on SGL?
  20. I think proper O rings or 3D printed TPU sealing rings would be a much better bet than silicone sealant. I need to change hat from botcher to engineer!!
  21. Thank you James. I really couldn’t understand most of the thread until you summarised in english! Essential for those of us who are just starting out on the imaging journey. Paul
  22. Lengths of elastic are probably an optional extra
  23. Is there any refractors that are fast, not reallllly expensive and longish fl?
  24. Hi Mark I have one. Will probably part with my Mak127 and therefor the dew shield. Are you still looking?
  25. I bought recently the 2" 2 x Powermate and love it for lunar photography. Haven't had a chance to use it for much else yet but looking forward to exploiting it to the full.
  26. It was failed sealing that caused the problem with desiccant to dry ordinary air. Maybe I should re-examine my sealing method - I relied on silicone bathroom sealant. For the few days during which the casing stayed sealed and the air dry, the ASC worked perfectly with the water cooling. Except it needed a bit more than the 2W dew heater I was using - that is not a problem.
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