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Panda Alvin

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    72
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About Panda Alvin

  • Rank
    Nebula

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  • Location
    Southampton
  1. I'll pass on this one due to distance. Plus its also my town's Christmas light switch on / fireworks day. Fingers cross for you on clear skies though! Could do with some good weather by then. Alvin
  2. Panda Alvin

    Tokina AT-X 11-20mm

  3. Panda Alvin

    Hyperflex-7E2 (9-27mm) zoom

    As per title, I'm enquiring for a SW / OVL Hyperflex 9mm - 27mm zoom (to clarify, not the 7.5-22.5mm variant). Please feel free to let me know if you have one available via pm or post. Thanks, Alvin
  4. Panda Alvin

    Barlows with t-ring adaptors

    It's more expensive but if you do buy the Barlow from FLO, you could do without the 1.25" nosepiece. The Barlow sold by FLO comes with T thread so it could fit directly on the T ring. eg like Geoff Listers's image
  5. Panda Alvin

    Skymax 127

  6. Panda Alvin

    Barlows with t-ring adaptors

    You pretty much got the right one, what Peter is saying is that you don't really need the extra tube between the T-ring and the nosepiece in this image. The item is still OK because it is removable and you just fit T ring directly to nosepiece instead. Most basic telescope accessories have an industry standard threads so will fit each other unless physically buy a different size or item. So to visualise this will be your image train - Nikon D90 >> Nikon T adaptor >> T2 to1.25" Nosepiece >> 1.25" Barlow >> Telescope
  7. Panda Alvin

    What has experience taught me?

    Very good read, all the points are pretty much very relatable to what I am experiencing right now. I have recently started and sometimes struggle to find objects both in Sky and through telescope in my fairly light polluted back yard. When I eventually find the object, it feels like you have overcome a challenge which feels like a reward in itself, even if the view you get is not so great or faint. I do also sometimes feel pressured to observe at clear nights, like tonight when the forecast is looking good in my area. I feel like I need to go out and learning more, but I have work tomorrow and god knows when the next good day will be. Wife will also make a passing comment that I spend too long outside but then again also make another comment when I haven't t touch the scope for a while! Since started on this journey, I quickly realised this hobby has very very bad influence on my wallet. The initial budget I had set at the very beginning is now 4x over that limit.
  8. Panda Alvin

    Wider FOV eyepiece for Mak

    Throwing in my 2 cents wall of text here… I have the 1.25” Antares 0.5x focal reducer, which fits on to the end of the Baader MK4 zoom. As for me, I only started in late July this year so I am still very new to this. To start with, I struggled to find Andromeda. I know roughly where it is and how it should look like in a 5” scope, but just I couldn’t find it on my Mak. Star finding is also difficult with the limited FOV (even with the go-to mount, it doesn’t always point accurately) and because of that I really wanted to increase it. I thought about upgrading, via a Mak - SCT adaptor, then either slot a 2” visual back to accept bigger eps, or buy the 0.63x SCT focal reducer (true be told… I did also get the 2” visual back). Before I went about it, I did looked at existing topics and posts regarding Mak upgrades. The comments were overall negative (not in a nasty way), ranging from potential coma at such focal reduction, to significant vignetting with the 27mm internal baffle tube of the 127 Mak. The general consensus is to mainly “stick at small objects where it is good at”. This advice did put me off doing so for a while until a cheap second hand Antares 0.5x came along for £9 which I was willing to take a gamble at that price. Despite still having major reservations, I was happy to treat it as an experiment, and probably consign it to my reserve astro goodies box should it not work out. When the FR came, I did a quick test on a terrestrial object. Long answer short, yes there was vignetting. However, it wasn’t a deal breaker for me because it was only very slightly noticeable in the corner of my eye; this was with the zoom set on 24mm (well 48mm) at 45°. Slowly zooming in, the vignetting disappeared at 20mm(40mm) at 50° for me. I am happy with this because I am still technically gaining FOV at this rate. I also guess the few comments around different forum, mentioning the human eye don’t notice vignetting less than 15% were also correct. Then two weeks ago, I went to an field meet for the first time. I was looking at planets until somebody pointed out that Pleiades had just risen up above the tree line. Mind you, I never seen Pleiades before (let alone know its Messier number) and I was trying to find it after slewing to the general direction. This took a while but eventually I think I found it, just by its 4 main centre stars that was brighter than the rest. At first sight, it really wasn’t that impressive as it was just some stars. This was until I added the reducer which showed more, not significantly but enough for me to instantly understand why people like it. You get a better sense of scale and pick out it's nebulosity. Such as an example from the simulation below. In reality the reduced 24mm it looks slightly tighter than the simulation, this might have been the “vignetting” at play, which I now can’t see at all in the dark. The two other people with me at the time, having 3-4 years’ experience each also had a look through my scope. I asked if there were any issues with the view, but neither could find anything wrong with it. Anyway, after that session, Pleiades also became one of my favourite and I can’t wait to look at it again properly when the next opportunity arises. Overall personally, the reducer is one of the best astro experience for money I have brought to date (I guess due to low price and low expectations). For me it just happens to fit in really well, but I suppose the still quite mediocre F ratio of 5.9 and FOV limited to 45° I had may have played big a part in quality. I suppose your mileage may vary depending on your existing experience, and the EP and scope you are using (especially OPs 6 inch probably have bigger internal baffle but longer focal length). Oh and as for the Andromeda I talked at the beginning, I definitely needed that reducer to find it. In a way, it helped defined between the dark sky and the grey fuzzy cloud. The object just stood out a tiny tad more.
  9. Going bythe theory of "big rip", I think that will end everything first by tearing the biggest object, eventually down to the sub atomic particles, before all the stars can use up all available hydrogen in the universe. . In that scenario hydrogen will cease to exist but I guess everything will too.
  10. Panda Alvin

    Canon EF-S 18-55mm

  11. Panda Alvin

    DSLR Hot Pixel

    Oh I also forgot to mention that I did the test on the Canon long exposure noise reduction mode, it does remove the very visible stuck pixels leaving only the less visible... well noise in the image. Only concern is that if I did this in the timelapse, the sequence might get less smooth ?
  12. Panda Alvin

    DSLR Hot Pixel

    Thanks the suggestions so far, I have tested my camera and looked through some AP software just now and this is what I have discovered. The stuck pixels are still in the same brightness and location in a dark room. I always take pictures on both RAW and JPEG, but always use RAW as much as I can / whenever possible. I know dark frames can be applied on DSS photos Stacking and in Startrails (cumulatively), but is there a software out there that applies dark on a frame by frame basis (and en masse) to go in timelapse? I have not come across Astro Pixel Processor or AstroArt before, so I have no knowledge if they could help on this situation. Sorry I am still very new to all these software myself and may have missed some functionality here and there. I've just learnt Adobe Lightroom automatically removes 1 pixels stuck pixels so the ones I see must be bigger than that. Anyhow, I think I will hold on to the camera and explore ways to improve on what I have instead.
  13. Panda Alvin

    DSLR Hot Pixel

    Yup, done that several times before hand but no luck with it. Not sure if I did something wrong or the function isnt working / broken for me.
  14. Panda Alvin

    DSLR Hot Pixel

    Thanks, and yep I see the function which is off at the moment. If I do turn it on and want to keep the same movement rate, would you know if I should ramp the ISO to 3200 and exposure to 12s? Or would the noise to signal ratio increase too much and not worth it?
  15. Panda Alvin

    DSLR Hot Pixel

    Edit: Sorry if this should be in the Getting Started Equipment Help and Advice section. Please feel free to move this if required. I have recently brought a Canon 550D (with 24k shutter count) to learn and master astro timelapse. After reviewing a test run I noticed there are lots of stuck pixels against the rotating night sky. I then did a black exposure with the cap on, and the shot came up with even more hot pixels than I was mentally prepared for. My wife has a 1000D and it is nowhere as bad. Uploaded a Jpeg if anyone wants to see, or attached a CR2 file if anyone wants to have a play. This is a 30 sec exposure on ISO 1600, the standard setting I predict to use in the field I have done both air blowing and manual sensor clean but the pixels are still exactly where they are. I read up they can be removed in post processing but the thing is, how much is too much ? Should I be concerned about this and have it returned or is this to be expected and should be embraced? Thanks for reading in advance And for those who are curious about the practice timelapse.... 11mm (APS-C), 201 frames, 25s exposures, ISO 800 , f/2.8, Bortle 5-6, Adobe Lightroom IMG_4792.CR2
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