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Uranium235

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Everything posted by Uranium235

  1. Uranium235
    Forgot to mention, its also up against the Redcat from WO - all of a sudden the mid (price) range is getting quite crowded...lol It would help if we knew exactly what those ED elements were made of. Anything less than FPL53 will not be sufficient. Edit: Ive asked them directly what glass it is, awaiting a response
  2. Uranium235
    Yeah, its going to be up against the Canon 200mm L series - which (as far am im aware) cannot deliver a flat field to the corners over APS-C without being stopped down. So thats the benchmark its got to beat. I guess one other thing going for it is that the flange-sensor distance is a far more comfortable 55mm. Still need to see how it handles CA though, and that wont come until we see some shots in broadband... M45 would be a good test. Flare tests would also need to be done for any out of shot monsters like Rigel.
  3. Uranium235
    lol... 699 there but once it hits the UK - you can be sure it will be more However, all the test shots Ive seen are in narrowband - I need to see something in LRGB or OSC to see how it handles broadband imaging.
  4. Uranium235
    Hmmm... ive just come across this, astro stuff from Sharpstar occasionally pops up in my feed, which is usually ignored (until proven) - but this one caught my attention: http://www.askarlens.com/index.php/wap/class1/179.html Its a 200mm f4 lens, with inbuilt microfocuser (nice touch). And the test images ive seen so far are actually quite good in the corners - that might have something to do with it being f4... so it might not be suitable for someone looking for a photon hoover. And its got just 6 elements in three groups, not nearly as complex as some others (the Sammy 135 f2 has 11 elements in 6 groups!).... whether that is to its detrement.. I dont know. Its too new to comment until Ive seen more data. Thats the trade off I suppose, swap a bit of speed for tight corners. The price, I reckon it will be about 800 quid.
  5. Uranium235
    100% correct on all counts! (apart from its 44.1mm but im just being pedantic...lol) Dont forget, when you add a filter between the lens and the camera - you need to take into account the amount of spacing you need to add (not subtract). Astronomik: Add 0.33mm Baader: 0.66mm Astrodon: 1mm Yes, it does matter about adding the spacing when working with an f2 lens because the filter thickness can throw infinity focus out quite a bit. If you have a mix of filter brands in your wheel, then you need to come to a compromise spacing.
  6. Uranium235
    This way up
  7. Uranium235
    Ahh, my bad didnt see it was mount related - but even so trying to gain 4min+ just through modifications to a stock mount seems... optimistic at best. You really have to shell out some cash if you want top notch unguided imaging.... if I remember rightly one of our (now sadly departed) members (Per) used to do everything unguided - but he had everything modelled right down to the finest detail. Quite right on the histogram, I personally leave a gap of 20 - as even though that "gap" looks like there is nothing in it - it can actually contain faint nebulosity or dust that would otherwise get clipped.
  8. Uranium235
    Hang on.... stop right there...lol. No camera modification on Earth (apart from increasing the pixel size) can influence the maxiumum length of an unguided sub... that is determined by both the mount and the focal length of the optics. With a 130pds, you would be lucky to get 30s unguided without trailing (@ 1x1bin). You might be able to get longer unguided @650mm, but that takes a lot of fiddling. Just wanted to clear up that bit of mis-information
  9. Uranium235
    If you live in London, then its going to be narrowband imaging only im afraid (if you want any hope of a good image). Keep the star adventurer, buy a fast lens (eg: like the samyang detailed above), a lightweight cooled CMOS camera + some filters. Should come to less than your budget. Edit: Just need to add that your choice of camera needs to be mono
  10. Uranium235
    The SW 0.9x will be problematic when you point it at anything bright. Try taking an image of M45 with it and you will soon find out Remember, the review posted earlier is based on using an F4 newt - which will always be next to impossible to get flat over a 22mm diagonal for your average imager. However when you apply something like the Baader to an f5 130pds, the results are much more consistent. Its entirely possible to (just about) get round stars over a KAF8300 using the Baader MkIII (example below)
  11. Uranium235
    A bit of late night Ha imaging NGC6820 Just 90min, I'll pick this up again in a few weeks when I wont have to wait so late for it to clear the tree.
  12. Uranium235
    A bit of messing around for an hour last night (LRGB) :
  13. Uranium235
    Astonishing photos... I had the same issue with a 200pds, great replacement focuser - rubbish baseplate. So I designed my own as you did, but I had it 3D printed instead. When designing, have a think about how it will all attach to the tube. Might be worth uprating the bolts to M5, and where the nut goes on the inside - a flexible placstic washer or something simlilar to spead the contact area of the nut out a bit more (flat nut on a curved surface is never good).
  14. Uranium235
    By killing all star colour in Ps: Filter > Noise > Reduce noise Strength: 10 Preserve detail: 10 Colour noise reduction: 10 Sharpening: 0 You can either apply that to the whole image, or on a star selection only.
  15. Uranium235
    Here is the (stretched) master flat taken with that panel, looks fairly normal... apart from the excessive amount of motes...lol
  16. Uranium235
    Depends on whether your camera has a shutter or not. The QSI does (as is usual for KAF8300), so I usually give it at least 3 seconds per flat - hence the need to dim sufficiently
  17. Uranium235
    When it turns up, you will notice it has a grid pattern on the illuminated side. That will disappear once you put a few sheets of A4 on it - you probably need about 3 or 4 sheets to dim it sufficiently enough for lum flats on its lowest setting. For narrowband just hit the power key once or twice to increase the brightness (you have three levels). It runs fine for ages from a small powerbank
  18. Uranium235
    This is it mate https://www.amazon.co.uk/Portable-Adjustable-3-Levels-Brightness-Animation/dp/B07GSVB7RR
  19. Uranium235
    More than one way to skin a cat on this one, personally I would create a fake background (with fake noise) and bursh it in with a layer mask - blend mode ligthen (so the stars dont get touched). Takes practice, but it can rescue a project from the bin.
  20. Uranium235
    FYI, the lightbox I used was this - 14 quid from amazon: I then created a protective cover and OTA attachment using the box it came in, and a bit of foam oh, plus 3 sheets of A4 to further dim and diffuse the light. The pic shown is with it on max brighness, I've only used the lowest setting so far on lum data. NB will probably require it to be kicked up a notch or two in brightness. Its amazing what you can do with a bit of glue and tape Probably needs a bit more tape around the edges, just to make it star party friendly.
  21. Uranium235
    Testing the new lightbox I built tonight, it seems to produce much better flats than a monitor - runs off usb power with variable brightness, which is great Just applied it to some M106 data I took a last week, which I didnt post here because the background was a bit blotchy. Flats from a different source seem to have cleared this up somewhat.
  22. Uranium235
    As promised Michael your colour data, plus my mono from the same subject (shot on Sunday evening): Was the colour shot with a DSLR? Feels like it becuase I had to remove quite a bit of background blotches/noise.
  23. Uranium235
    Lockdown astrophotograhy About 3 hours in 4min subs with the ASI178 Cool
  24. Uranium235

    Never thought I'd be saying this but.... guiding tonite! :)

  25. Uranium235
    Quick update on my quest to collimate via a camera. Given up on the pinhole concept for now, as I spotted a super cheap 8mm CCTV lens (cs mount) that will work with either my QHY5 or 178mm camera. I can just pop that on and collimate / tinker until im blue in the face
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