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Uranium235

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Everything posted by Uranium235

  1. Yep indeed if the modification works, Im going to order a bunch of them to be machined, but I have to run it past admin first. Not sure where I will stand on intellecual property rights though
  2. Adam, Im currently working on a fix to completely eliminate the droop issue with the EOS bayonet connection (conversion of the lens to M48 thread). Its going to be a prototype so watch this space and I will have some news in a week or two. Currently, the lens needs to be supported because its quite heavy, which causes compression of the bayonet fitting as the mount slews about - its only secured with three springs, which isnt really strong enough when imagng at f2 tbh - which is why people are supporting the lens to minimise the movement. Moving to an all-threaded connection will (in theory) resolve that issue. Another bonus of going all threaded is that you will claw back the space taken up by the EOS-T2 adaptor.
  3. Looks like im back in the Samyang club ordered a new 135mm today (should get it next week). Excellent.......
  4. Team scumbag at the ready!
  5. Just a thought..... if im to attempt modding the 135 I will need three measurements (I cant do it myself since I dont currently own a 135). The rear aperture looks quite wide when compared to some M42 lenses, so I need to know exactly what it is before hunting around for an M42 donor lens. If someone could whip out a digital caliper or ruler (for a rough measurement) that would be handy The three measurements I need are as follows: If I cant find a lens that is suitable, then I know a chap who just might be able to machine something. If I were to go down the custom route, it would probably end up being M48 instead.
  6. Sounds like a plan! I've got a bench drill so I could drill any additional holes that might be required. The M42 donor lens doesnt even have to be working, as im taking it apart for bits. Edit: Patent pending....lol
  7. Looking at the rear end of a Sammy, it looks like the bayonet can be removed (held on by three screws). It might be possible to engineer something to replace it, but it would need to be precision stuff, not something I could knock up on the kitchen table.
  8. Hmmmm. that PL thingy has got me thinking a bit. It would be so nuch better if there was a custom adaptor that did away with the whole bayonet business for standard photo lenses, it would hex bolt to the lens (using compression) and be ultra short....lol... I know might be dffiicult to envisage, but given some time and perhaps a test 3d print (before moving on to aluminium), it might be possible. lol... I wish Samywang made an M48 or T2 fit version... that would be fantastic
  9. I was looking around for a cheap used 135mm sammy, but came across something very interesting this evening. Samyang have released a 135mm cine lens, rated at T2.2 (transmission value, rather than F ratio). Its expensive, but I found that you can get a variant with a fitting called "Positive Lock". Which gives a much more secure fit than the standard EF springs found on your typical camera mount (as cine lenses are heavy beasts). A little more digging found that there is a PL - T2 adaptor available, and the flange-chip distance of the lens is a generous 52mm. Would be nice to see someone with deep pockets give that a go for astro but as always, best to keep your powder dry until someone else makes the leap. Its only been released this month, so its yet to get any attention. If its anything like the standard 135, it would be quite special - especially given the secure nature of its mountings. The price? £1544 .... hahahaha yea right (if I won the lotto) Weight? 1.4kg .... lol... Thats a lot of dough for 135mm (though probably cheap in the world of cine) https://rokinon.com/xeen/xeen-cine-system/135mm-t22
  10. It is entirely possible to get rho ophiuchi from the UK you just need a dark, unobstructed location, and pick your nights well (no fuzzy skies). Now is a good time for it. But you have to stay up well late for it...lol Actually, I'm thinking of getting yet another of these lenses since my new home has such a limited window of opportunity I would need to cram in as much data as possible in just 3 hours... and the only way to do that is to go superfast.
  11. It also depends on the bandwidth of the filter. A standard Baader 7nm filter is fine in my experience, however a 3nm Astrodon would be more inefficient. A 12nm Astronomik on the other hand would fare better. But hey, youre at f2!! so a slight loss in transmission is no big deal at that speed.
  12. There ya go... M87 jet from the 130: Crop
  13. Just working on it now mate (its been a while since I last got out). But.... ive just checked the first sub (240s) and bingo... its there!! my first (intentional) jet! I'll leave the camera running for an hour or two - just for the sake of nose reduction - and hoovering up some background fuzzies. Im getting a few unexpected bumps in RA guiding though, no idea why becuase there is absolutely no wind our there tonight.
  14. You have some degree of control over the rotation (prior to attaching camera) by simply taking out the screws on the tilt adjuster and rotating it in portions of 120deg, if you get it close, the rest of the camera orientation is finished by tweaking up the tightness of the extention rings (not too tight though... dont want to bind them). Its kinda arbitrary, but Ive never failed to get the camera landsacpe or portrait with it (in repect to the focuser). Collimation is done simply by removing the corrector (it screws out). Or... if you have a short cheshire in your box you can just leave the CC in, attach an EP holder to the M48 thread and off you go... but I do stress that it needs to be a short cheshire - otherwise you will hear the glorious sound of metal on glass... not good!
  15. Have you checked if the jet correct? If it is - im impressed! Jets are something i've been trying to capture for years...lol. I dont think I have a close up of that galaxy in my archive, so I'll have to get some fresh data while i still can. It might be worth me getting the 178 on that for some close-up action... and possibly enhance the jet slightly with some creative layer masking in Ps.
  16. Just had a bit of a brainwave..... in future get a couple of dumbell weights and hang (or place) them on the accessory try/leg spreader, that would provide a bit more protection. Or maybe a way to anchor the tripod?
  17. Sounds awful mate.... that must have been some gust of wind! Ive never heard of an NEQ5 being blown over before. To look on the bright side, the 130 isnt an expensive bit of kit to replace and your camera was not damaged. Just think what it would be like to have a nice APO and CCD camera hit the floor!... ouch!
  18. Hmmm, tried to get some more of that background dust to appear - but it blew up the stars slightly. Might be worth taking it down the LLRGB+SMI route, that would take about 3 hours though
  19. Exactly what I would have said The 1600mm and KAF8300 have roughly the same sized sensors, so it should work (with a little tweaking to get the flattest field possible). The 1600 is cheaper, so that will allow extra headroom for a couple of filters etc if the budget is around 1k ish. Get a Ha filter first, that will do the most for you (well... in about 2 months when the MW swings back around). Even so, the resolution with the 1600 is 1.2" p/p - which is still pretty damn high, but not so high as to exceed the resolving power of the telescope aperture (~0.9"). The 178 is best used either as a galaxy buster on the 130, or if you want a larger FOV - mount it on something like a Samyang 135mm f2 or the 200mm Canon EF lens. The 178 with a 135mm lens: And the 178 with a 130pds: Massively different FOV sizes there.
  20. Thanks guys But we have to take a number of things into consideration if you want to get the best out of it. Starting off with the mount, the 130 is quite light so it never bothers an NEQ6 (not even close...lol). Secondly there is the camera, that is were the magic happens - which as we all know can only be achieved with a mono (yes... there, i said the M word ) CCD or the one of the recent crop of cooled CMOS cameras because you need very low noise to get good data. This point would need a lot of consideration in regard to sensor size and/or pixel size, and what you want to image. Then, its the 130pds - probably the simplest way to deliver photons to the sensor..... no fancy-dan glass required (barring the coma corrector) - just a couple of small mirrors... its as uncomplicated as it can be Lastly, its guiding, choice of target, framing and mosaic planning and total integration time. But at the moment, its my only telescope - so its going to get used a lot, especially now I've got it bagging galaxies with some decent detail. With the ASI178 though, ive found it takes a 100+ short(ish) subs to get a very clean image.
  21. Just a quick 2 hour pop at M51, no proper calibration though so its a bit on the rough side. Also had a bit of flex somewhere, but I will track that down and eliminate it. (taken with the ASI178MM cool)
  22. Heart nebula with the ASI178MM cool: (50x240) Belt/Sword Bubble to Cave (25x240)
  23. Not to say that the 200 cant make a good image (because it can). But the difficulty is in a different ball park compared to the 130. Plus your choice of targets would be limited by the fov available from a 1 metre focal length.
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