Jump to content

sgl_imaging_challenge_2021_2.thumb.jpg.72789c04780d7659f5b63ea05534a956.jpg

johninderby

Members
  • Content Count

    12,917
  • Joined

  • Last visited

  • Days Won

    72

Everything posted by johninderby

  1. Yes they would be a simple bolt on replacement with no mods needed. The baseplate is designed to fit a 9" and larger dia. OTA (8" mirror). One thing to watch out for with the low-profile focuser that comes with the baseplate is that some dealers sell it with the narrow baseplate that isn't a straightforward bolt on replacement. FLO however sells it with the correct wide baseplate that you would need. However as I mentioned the wide baeplate can be found on Scopes'n'Skies Astroboot for £2.00 so it does work out a bit cheaper to get the S'n'S baseplate and then buy the MN190 crayford. John
  2. In general a replacement dual speed crayford will be of better quality that the standard focusers that come with a SkyWatcher dob The key advantages are: Smoother more precise focusing. Virtually no slop in the drawtube as you move it in or out. More accurate collimation of your scope as when you collimate with the drawtube in one positon it won't change when you move the drawtube in or out. The fine focus knob requires only a light touch of your fingertip to move it, hence reduced vibration of the scope whilst focusing and particularly with a dob less likelihood of intentionally moving the sc
  3. They don't have an English translation on the website but here's the Google translation. John *************************************************** TS APO 80/500mm - f / 6,25 - FPL53 APO member ... a high quality 2-element apo with very good color correction for the observation and photography The objective of the clean-made TS APOs reduces chromatic aberration to a minimum, not interfering. The result is sharp, especially high-contrast observations and photographs. Nature lovers who appreciate the finest details in natural colors lay line, such as bird watchers, or even astro photographers in t
  4. Re: Ethos and FOV Forget the FOV of the Ethos, it's the quality of the view that makes them so good. The sharpness and contrast are what I remember most about using them. John
  5. Yes you can have high mag and wide FOV, but it will cost you. With the advances in glass and anti-reflection coatings the latest premium eyepieces with 7 or 8 or even more elements are just as good as the old specialist planetary eyepieces for light scatter and light transmission rates. Things really have moved on. My latest high power acquisition (don't ask the price ) is an Ethos SX 3.7mm 110 degree FOV eyepiece, and I would rate it as just as good if not better than my old TMB monocentrics for sharpness and contrast. Viewing the moon with this eyepiece is an amazing experience. John
  6. As I'm going to be using tuberings to mount the OTA in a similar way to the OO bases I can then just use another set of tuberings with a dovetail to mount the OTA on an EQ mount later on if I wish. The best of both worlds. This is going to be a bit of a grab'n'go scope, and with the thin OO borosilicate mirror and a cooling fan it's hardly going to take any time at all to cool it down enough for observing. The 6" Mak is an excellent scope, very compact and portable but the cooldown time is an issue and optically a 6" f/8 Newt/Dob is more than a match for it. John
  7. It's not an OO mirror cell as OO doesn't make a CNC one in the 6" size (OO starts at 8"). It's an American made one that came with the OO mirror set when I bought them from another SGL member. http://www.opticalsupports.com/mirror_cells.html The cell mounting had to be trimmed by 5mm on the outer edge to fit within the standard SkyWatcher end ring and the standard tube mounting brackets were removed. Fortunately three holes in the cell plate matched up with the three large holes in the bottom of the SkyWatcher end ring so I was able to bolt it in place that way using three spacers. Although i
  8. A nice unbiased review, well done. I agree that the ES is a very good eyepiece, but at the prices they're asking in the UK for the ES eyepieces I can't see them threatening Ethos sales very much. And also they're so big and heavy. Having owned or used most of the Ethos eyepieces I find it's the sharpness and contrast that makes them great eyepieces. The biggest mistake that many people who havent actually used them make is to assume that it's all about FOV, it isn't, it's about optical quality. In a dob or undriven mount however the FOV is nice to have as you're able to just move your eyeba
  9. I use AastroZap breathable caps on my OO 14" dob and put them on as soon as I bring the scope in. Takes care of letting any moisture out of the tube. Unfortunately no one seems to stock them in the UK. John
  10. Revelation is Telescope Houses own brand so they may be able to help you. John
  11. Hi Graham I'll pop it in the post (1st Class) this aft. Cheers John
  12. I've got a spare one here. You can have it for the cost of the postage if you want. I just checked the weight and £2.00 would cover the postage. John
  13. RVO have allways given great service and do let you know what's going on. A while ago I ordered an eyepiece on-line from them and I got a phone call shortly afterwards from Adam apologising for not having the eyepiece in stock. Their computer apparently showed one left in stock even though it wasn't there. How many dealers would take the time to call and apologise for not being able to ship your order right away? John
  14. Those bins are the same as the Helios Apollo 15x70s so just look up reviews on the Helios Apollos. Great bins. APM is not just a dealer but also a manufactuer, and they do produce some high end equipment. APM manufactured the TMB scopes until the latest "TMB Signature Series" (not what I call real TMB) and now produce the proper quality TMB scopes under their own brand name. Just don't ask the price of their 500mm Triplet APO (that's 500mm aperture BTW) John
  15. Ah, but you should have seen it last week before I finally got round to a proper tidy up so I could see what I'm doing in there. John
  16. Nothing to do with the focuser, but there are also some mods underway at the other end of the OTA. John
  17. Yes the focuser fits right into your existing baseplate via the grub screws just so long as it is one that takes a standard GSO, Antares etc. crayford. The Sky-Watcher low-profile crayford focuser includes the baseplate. http://www.firstlightoptics.com/proddetail.php?prod=sw_low-profile_focuser I've just noticed that the low-profile crayford focuser price has dropped to £122.00 It's simply a case of buying the same crayford focuser with or without the baseplate. Saves some money if you already have a suitable baseplate, or as in my case I needed a special baseplate to fit a smaller OTA, and s
  18. Telscope Service is really helpful so perhaps you could ask them if they could ship it by regular airmail. John
  19. "Dual-speed Crayford focuser for Skywatcher 190MN" http://www.firstlightoptics.com/proddetail.php?prod=skywatcher_focuser_190MN Just for the 190MN, well not really. It's identical to their low profile crayford focuser (except for the knobs) but comes without a base plate. However as it's the standard GSO, Antares, SkyWatcher etc. fitting all you need is a standard base plate such as is available from Scopes'n'Skies for £2.00 or £3.00. In other words SkyWatcher is charging you £30.00 for a baseplate when you buy their low-profile focuser. I've just posted in the DIY section on fitting one of
  20. Fitting a 2" Focuser to SkyWatcher 150PL Newt OTA I've just started working on my little 6" f/8 planetary dob project using an OO UK 1/12PV mirror set and CNC mirror cell and have got hold of a 150PL OTA as the starting point. I'm still designing the base and bearing arrangement, but expect it'll be finished by Christmas. The 150PL OTA comes with a 1.25" R&P focuser. And while the focuser is actually not bad at all really for an inexpensive focuser I wanted a proper 2" crayford focuser. SkyWatcher has now released their " Dual-speed Crayford focuser for Skywatcher 190MN". It's actually ide
  21. I read a test on the various brands of Class 10 cards recently and Transend came out at number two overall for quality and reliability and were only beaten by a brand that cost several times as much. Amazon ratings can indeed be a bit peculiar sometimes. John
  22. There is one other major cause of reduced contrast in a Newt or dob that most people forget about. Stray light entering the bottom of the OTA can wash across the surface of the primary mirror and cause as much of a problem if not more than stray light at the focuser end. Flocking around the inside of the bottom of the tube can really help. A simple experiment is to cover the bottom end of your scope to seal out any light and see what happens. John
  23. Congratulations, lovely looking scope. If it performs as well as early reports indicate it should be an exceptional scope. I note Celestron quotes "Fastar compatible for fast f/2 imaging" John
  24. Pyrex does cool down faster and tracks the ambient temperature better, but in smaller scopes (6" or 8") plate glass still cools down quickly enough so that it's not a problem. I find the biggest advantage of Pyrex or other low expansion glasses is the way that they are able to track the ambient temperature. Once cooled down, and if the outside temperature isn't dropping too fast, plate glass does perform as well, but fans can be essential even while observing.. For example the 16" Lightbridge with it's plate glass mirror, while a great scope for the money, can take hours to cool down so you ha
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.