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E621Keith

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Everything posted by E621Keith

  1. Like others said, lens pen has a soft brush and a microfibre pad for cleaning optics. While it's a nice gadget, I would not recommend it because it's a dry contact cleaning method. If you need to clean your eyepiece, first try a air blower. If you can't dislodge it, then you should consider wet clean method such as Baader fluid + thick lens tissue. Dry contact cleaning methods, such as dry microfibre cloth and lens pen, are mostly likely to scratch your optics.
  2. +1, get the Pentax XW, Leica ASPH zoom, or one of those Nikon NAVs. To see details in M42, I'd say the following factors are more important than your choice of eyepiece. Dark sky, atmospheric transparency, scope aperture, scope optics quality. If you've got all those sorted, Orthos are the obvious choice for deep sky on a budget. Also have you consider using filters? UHC filters can help bringing out the details too.
  3. As others said, even if you don't consider window glass, the thermal current from the house alone is enough to ruin the view.
  4. I had a Pentax 8-24mm until recently. It was a well built eyepiece. The field was sharp, the colour was neutral and it had less scattering than most sub £100 fixed eyepiece. The background is darker than the Nikon's MCII zoom. The zoom ring was very stiff because of the waterproof sealing. It's not a problem if you used compression ring type eyepiece clamp, but I put a big scratch on the barrel the one time I use it in a diagonal with set screw. From what I read online, it's an upgrade to the Hyperion zoom, but I will not recommend it at the moment. Pentax 8-24mm XL is a 6 element design that retails for around £400. Ricoh has a new 9 element 3 group zoom packaged with their new Pentax PR 80mm sporting scope. The new PR-XL 8-24mm zoom has a slightly wider field (43-63deg) and more importantly an RRP of £280. I haven't seen any store selling the new eyepiece yet, may be Ricoh want to clear its stock of old 8-24mm before they start to sell the new one. If you are interested in the Pentax, I'd wait for review of the new model. If you can't wait and is willing to pay £400 for a zoom eyepiece, I would spend another £100 and get the Leica.
  5. Very nice set up Olly. Do you know what is missing from that X'mas tree - decoration. It needs some cables and colour filters hanging off it and may be a statue of Sir Patrick Moore to go on the top. Why not go all the way and build a WASP with eight FSQ.
  6. I have a Vixen and a Borg turret. They worked ok with small eyepiece like plossl and ortho. They did't work at all with larger eyepieces like LVW. The Borg uses a friction to clamp the eyepiece, just friction from the rubberised socket, no set screw or compression ring. Plossl and orthos were OK, but I didn't have the nerve to risk any larger eyepieces. The Vixen is nicely built, but it's locked in place using a spring loaded ball bearing. Unfortunately the weight difference between a 13mm LVW mounted on one side and a 5mm LVW mounted on the other was enough to overcome the lock and rotate the turret. IMHO, a turret will work with small eyepiece that won't cause balance issue, but unless you buy one of those expensive Van Skyes, TEC or Tak turret, it won't work with eyepieces that's big enough to upset a scope's balance.
  7. Tom, do you need arcsecond accuracy on printing press gear box? A lot of people quote car gear box as an example of a highly stressed gearbox, but a car can still run even after losing a few millimetres from its gear teeth. An imaging mount's will become pretty much useless if its worm was out by 1/100th of a degree. Is a light weight lube sufficient to ensure the gear teeth will not lose more than a few microns from wear over the life time of the mount?
  8. Dave, I just saw your PM and then saw this thread. I don't think there is a problem with your mount if the movement is only 5mm at the eyepiece end of your 250mm Newt. I doubt the ADM saddle upgrade will solve the problem. First of all, as John mentioned, your dovetail is an Orion dovetail. It works differently to the standard Vixen dovetail. Normally, the Vixen saddle's locking bolt pushes the Vixen dovetail into the base of the saddle and the opposite flange. Unfortunately, Vixen GP's saddle had raised 'Made in Japan' markings on the saddle base which could make flat dovetails unstable. Vixen own brand dovetails have a hollowed section in the base which provided clearance for these letters, but other brands' dovetail may not. Orion's dovetail was designed to engage the top of the Vixen saddle. The locking bolt forces the top of the saddle flange into the dovetail. This design also lifts the dovetail off the saddle base, so the 'Made in Japan' letters will not interfere with the fit. From my own experience, I felt the Orion style Vixen dovetail plate was more secure in a regular Vixen saddle than a normal vixen dovetail. Your Orion dovetail plate has integrated stoppers at each ends of the dovetail to prevent the scope from accidentally slipping off. However, these stoppers will make the dovetail plate incompatible with ADM's or other long pressure plate type saddle. If you buy the ADM saddle upgrade, you must also replace the dovetail. Anyway, I don't think the saddle plate or the Vixen saddle is the source of your problem. 1. Can you describe the 5mm movement you felt at the eyepiece? Is it a loose 5mm movement or a damped 5mm movement? If it is the former and the scope is rattling, then there is something wrong. If the movement is lightly damped, can you look at the joint between the saddle and the Dec axis (the line between your motor and the clutch handle). Can you seen any movement between the two when you push the scope while the dec clutch is locked. If you can see movement, then it's caused by backlash error on the dec worm wheel. A saddle upgrade will not solve this problem. 2. Next, take a step back and look at the whole mount when you push the scope with all clutches locked. Is the flex restricted to the dec axis only, or is your whole mount flexing? I can see both types of movements when I mount my 14kg 125/6.4 refractor on my GPDX. I also get the first type when I mount that scope on my IEQ45, but thanks it IEQ45's unique anti backlash mechanism, I get more movement than the GPDX This video showed the amount of movement I get when I pushed my scope at the eyepiece end. Skip to 1:07 for the GPDX's flex. http://www.youtube.com/watch?v=IcDI46JBzWs#t=0 If the movement on your mount is similar to those in the video, then it's caused backlash error and overloading the mount. The saddle is not the cause of the problem and upgrading your saddle will not help. The only way to reduce this movement is upgrading to a bigger mount.
  9. Yes, those are 1.25" eyepieces. The 22mm LVW will give you a TFOV of 3.3deg and a magnification of 20x in the FSQ85, which is more than wide enough for most targets. You may want a smaller eyepiece for higher magnification. You only benefit from 2" eyepiece when the field stop diameter is wider than 27mm which is the maximum field stop a 1.25" barrel can support. This is achieved at a focal length of approx. 24mm for a 70deg, 20mm for 80deg and 13mm for 100deg eyepiece. Large field stop is only needed in widefield eyepieces. Since the FSQ is fast astrograph primarily used for imaging, and rarely for visual, I don't see any good reason why you'd want 2" eyepieces, especially if you will only get 2 eyepieces. For occasional visual use, a 8mm (56x, 1.2deg) and 22mm (20x, 3.3 deg) would be a more sensible choice.
  10. There are a lot of excellent bird photo from the 300/4. If you need more focal length, there is always the option of using teleconverter.
  11. So is 'full frame' just a fancy name for progressive scan?
  12. Indeed, binoviewing is amazing. It turns ordinary eyepiece into something amazing.
  13. Did you mean Canon 200mm f2 or f1.8? Canon 200 f2.8 costs £600 new from a mainstream dealer. http://www.cliftonca....8L_II_USM_Lens
  14. But I think most people who use a ED80 for birds tend to use it on a stationary set up in a hideout. If you can live with the limited mobility and other limitations (e.g. lack of aperture iris) ED80 may not be a bad idea. However, I would consider a 300 F4 (if you do more birding), or a Borg71FL (if you do more AP). Borg has a number of accessories, such as aperture iris and front focuser, that will allow you to optimise their scope for terrestrial use. The camera moves in relation to the tripod mounting point when you focus a ED80, but a Borg with front mounted focuser or BU1 moves the objective instead.
  15. I think it's either the police can't be bother or the scammer operates abroad and outside our police's jurisdiction.
  16. The only other scope in this segment is the Tak FSQ106 which retails at £5k. I reckon this Vixen will be in the same region.
  17. For eyepiece, Televue eyepiece is among the best money can buy, while Takahashi are good but overprice. Since you are in Japan, I'd consider the Vixen NLV (JPY 9-10k) instead of the TV plossl (JPY 14.7k). The Vixen cost less and have longer eye relief, so they will be more comfortable to use especially at shorter focal lengths. Also consider the Vixen LVW (14.6-18.3k), widefield, long eye relief and cost about the same as a TVP. At a higher price point, Pentax XW (28k) and Nikon NAV-SW (27k) are very good alternative to the higher end Televue eyepieces. As for Takahashi adapter... I think Takahashi are infamous for the use of proprietary threads. You will need to check your Tak ends in a T(M42P0.75) thread, otherwise you need a Takahashi adapter for T-thread. It's best to check with your dealer.
  18. Are they? An orthoscopic eyepiece needs to be free from rectilinear distortion and angular magnification distortion, and should not show spherical aberration or coma down to F5. I think XW and Delos corrects for angular magnification distortion but not rectilinear distortion, so they are not 'orthoscopic', only 'orthoscopic like'. EDIT: Whether they are orthoscopic or not have no relation to whether they are good for planets. XW and Delos are the best long eye relief planetary eyepiece money can buy.
  19. A Borg with dedicated reducer will certainly beat a SV90+TV0.8x with the wrong spacer. All normal refactors have curved focal plane, so stars at the edges will appears out of focus without a field flattener. Field flattener only flatten the focal plane at a specific distance from the flattener, the focal plane will be curve either side of this specific distance. The flattener to sensor distance is determined by the design of the flattener as well as the scope. The distance is variable depending on the scope used. Borg and other scopes with dedicated flattener has predetermined flattener flange - focal plane distance. TV0.8x when used with third party scope do not. You will either have to experiment with different spacers to find the correct distance, or find someone else with a similar set up who has done that already. As far as I know, the popular TV TRF-2008 cannot fully flatten the field of a 80mm f6 triplet for a APS-C sized sensor. If you are interested in the SV90, check with Stellarvue to see if they have a dedicated flattener. They should be able to recommend you a flattener and be able to supply the necessary spacer for that scope. If you can afford a FSQ85, get it. It is the best 3" astrograph on the market. The FSQ is a 4-element Petzval, so it has a flat focal plane. It doesn't require a separate flattener like normal doublet or triplet. The FSQ has a native F ratio of F5, so it is faster than any scopes your listed with flattener.
  20. A well made doublet will always beat a poorly made triplet. Optical configuration doesn't tell you everything about the quality of the instrument. So no, triplet are not 'FAR' better than doublet, in some case they can be worse. (e.g. Pentax 75SDHF is a doublet with integrated flattener. ) The scope you listed are good scopes (not sure about the Sharpstar), but you also need to consider the reducer/field flattener. As for as I know, most of those scopes you listed uses generic field flattener. Borg designed their scope and flattener to worked with each other, so that is a significant advantage over the others. Borg 77ED was redesigned into the 77EDII specifically so it would work better with their range of flattener/reducer.
  21. Borg are good DSO imaging scope. In fact I think it more correct to say they are designed as astrographs and later adapted for birding use. 77ED usually show more CA than Chinese ED scopes when used on planet. You can see a lot of 77ED DSO samples on Borg's International dealer's blog http://digiborg.wordpress.com/?s=77ed Since you live in Japan, I would go for a Borg over any other scope on your list. Even more so if you use DSLR, because Borg reducers have DSLR system specific adapters that will give it the correct reducer to chip spacing. A number of Borg astrograph will illuminate 35mm chip, as well as APS-C. As far as I know, none of the Chinese scope will. Keep an eye out on this site. I've seen Pentax scope coming up a few time last year http://www.starshop....lebid-2012.html Kyoei seems to get a few used Borg every now an then http://www.kyoei-tok...brand/024/001/X http://www.kyoei-osa...65262/list.html
  22. That's what I thought as well, but that's what Orion is doing. They have a big red banner on their home page saying all prices on their site excludes VAT, and they have been listing ex-VAT price ever since VAT was raised to 20%. HMRC website is quite clear about shop prices and catalogue prices must include VAT, unlessthey deal exclusively business-to-business or export. I don't know if there is a legal loophole that will let websites list their price ex-VAT
  23. Good point. It makes sense to use 3-phase to smooth the current input. It still needs 3 phase mains, which can be very expensive to install. However, I guess if you can afford a $0.1M set up then the cost of getting a 3 phase supply and the electricity bill will be small change. I wonder if there are any commercial mounts with wacky transmission that I haven't mentioned. I think I've seen some ATM projects of all belt drive mounts that uses smooth V belt rather than toothed belt. I don't think I have seen any hydraulics or chain drive mount yet.
  24. If you are worried about whether Scope'n'skies is a scam site, then don't worry about it. Scope'n'skies is an established retailer for astro equipment. They may have mixed review, but it is a genuine site. I have ordered a few things from Astroboot and never had a problem.
  25. I think in the beginning of DSLR Imaging. Canon DSLR had a significant advantage over Nikon in terms of noise performance and a few other areas. Problems like noise reduction that cannot be switched off, shadow clipping, lossy compression in Nikon NEF (RAW) pretty much drove people away from Nikon. As more people use Canon, more people developed third party software and hardware for them. These resulted in Canon dominance in DSLR AP today. Canon knows it and devoted resources to produce 20Da and 60Da to show its support for the astro community. It's not a big surprise Canon cares more about astro than other SLR manufacturers, while everyone else left the telescope market, Canon still makes a lot of glass for Takahashi. Nevertheless there are a lot of Nikon users, so support for Nikon is better than Sony and Pentax. I think Maxim DL can control Nikon as well as Canon cameras.
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