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DirkSteele

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About DirkSteele

  • Rank
    Sub Dwarf
  • Birthday March 9

Contact Methods

  • Website URL
    http://alpha-lyrae.co.uk/

Profile Information

  • Gender
    Male
  • Interests
    Astronomy has been a part of my life since I was 3 years old, so I have been looking up for about 30 years, and using telescopes for about 25 years. My education followed a similar path and I left University having studied Physics and Astrophysics at both Undergrad and Masters level. I was also a founder member of the University Astronomy society and held the position of president in my last year of undergrad and continued on as treasurer in my masters year. My interest now is primarily visual astronomy.

    I currently own 7 telescopes, and the list clearly shows that I am a refractor man. The pride and joy of the collection is a 7" Triplet Apo (f/7) from APM in Germany, as well as 2 smaller Triplets (TMB 115 f/7 and the APM TMB 105 f/6.2 which is my primary travel scope). I also own three ultra portable Takahashi fluorite doublet Apos, the FS-60 CB & FS-60Q,as well as the FC-76 for those times when the 105 is a bit too large to take with me. Rounding out the collection is my oldest scope, the Celestron Nexstar 11 GPS.

    I love to cook (and eat!), and also collect retro video games, though prices recently have gone through the roof, so that has taken a bit of a back seat.
  • Location
    London, UK

Recent Profile Visitors

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  1. Scary! Lucky you noticed in time to catch the OTA. Did you replace like for like? Not sure I would have confidence in the product if that happened to me.
  2. Yep! That is probably the truth.
  3. Wave-front errors on diagonals are often quoted before the dielectric coating is deposited so the final surface accuracy can be quite different. Dielectric mirrors often have 50 or more layers applied. If each has an deviation of 3-5% then the overall wavefront error could end up quite substantial. I would suggest that you compare the image of the two side by side (and if your neck is up to it, using straight through viewing as the true baseline) to assess which produces the best image at the eyepiece (using same EP for each test, and quickly switch out one diagonal for the other). Assess the amount of scatter around bright objects such as Jupiter and the edge of the moon. Try to evaluate how much low contrast surface detail you can see on Jupiter. Also compare the vibrancy of any colours seen on the planet. Try some tight double stars and see if one diagonal makes the split slightly easier at the same magnification. I was recently able to split one very tough double by not using a diagonal at all, to keep scatter and optical components to a minimum. I have as yet been able to do the same with a diagonal in place. The modest amount of additional scatter is rendering the close dim companion invisible. Look at a good open cluster and try to determine which diagonal is showing the faintest stars. It is possible one will reveal slightly dimmer stars on the limit of perception. You could also perform a similar test on an emission nebula to see if one allows slightly more detail to be seen. You will need to be aware that atmospheric conditions can change from minute to minute so keep switching back and forward to try an eliminate those effects.
  4. The value of an instrument divided by the time I have owned it (and even more so the number of observing sessions) is how I have been able to justify some of my purchases so could not agree more. We definitely are lucky to be amateur astronomers in the current age. The pace of improvement in equipment, especially at the cheaper end of this hobby, over the last 10 to 15 years has been remarkable. I think back to what I paid for my first scope 25 years ago with paper round money and inflation adjust that amount to see what I could purchase today is startling! Not only do you get far more bang for your buck, but no doubt the quality overall would be better as well. And happy birthday to the Tak!
  5. Very nice Review. Moving straight on to read the 16x70 and look forward to the big brother of the group soon.
  6. Does the Quark use a front surface energy rejection filter? i.e. over the front objective telescope? If not, definitely not to be used with a petzval scope like the FSQ which has a doublet upfront and another at the rear near the focuser. The heat build up on the rear elements would not be desirable for the long term health of the Takahashi. EDIT: Whoops, just re-read your original post, see you are using the Baader ERF up front. Certainly reduces the risk considerably. Someone who knows the precise answer will be along shortly no doublt
  7. -favorite telescope: Should probably say my APM LZOS 180mm triplet but because it can travel abroad to really dark places, the Takahashi FC-76 DCU. -favourite accessory: Delos 10mm -favorite planet: Saturn -favorite star: Vega (Alpha Lyrae, hardly surprising) -favorite Nebula: Tarantula Nebula -favorite galaxy: Centaurus A (NGC 5128) -favorite cluster: Double Cluster -favorite observing site: Sossusvlei in Namibia. More locally, i.e the U.K., Brecon Beacons.
  8. Thanks! I had completely forgotten about that. Been a couple of years since I last read it.
  9. If it really is the same optics as the Skywatcher ED-120, the price differential seems to be rather large, even if the fit and finish of the mechanical components is superior. Any chance the minimum specified quality of the optics produced by the Chinese supplier is at a higher level than the Skywatcher (already very good based on reports I read)? As others have said, waiting for Takahashi to drop a FC-125 on us.... Though given I am soon to have a CFO in my life, I doubt I would be allowed to buy it!
  10. Turns out there may have been some play in the Cheshire. Have used a second Cheshire and a collimated laser against a plane mirror and all seems to be in order. So the original was capable of giving good and bad results.
  11. I was in Florida with my family in 97 and a launch was scheduled. We were across the water at the airforce base, so a few miles away. The sound seemed to take an eternity to arrive but when it did... Wow! It's the loudest thing I have ever heard. The vibrations in my chest were intense. Forget all the theme parks, that was the highlight of the holiday.
  12. ..........* *That means stunned into silence. Incredible!
  13. That will be my new astronomy definition of madness! One day that exercise will result in tears and possibly blood and bruises. It is easy to forget how big large refractors get. Happen to have my 3" FC-76 set up next to my APM LZOS 180mm triplet today. Please excuse the mess in the background.
  14. The Takahashi FC-76 comes in two regularly available varieties, the FC-76DS and the FC-76DC. The DS is a larger body scope weighing around 3kg but thanks to a sliding dew shield is actually shorter for transport than its narrow body, lighter weight (1.8kg) cousin, the DC. Unfortunately the DC model has a fixed dew shield which means at 650mm in length it is too long to be aircraft cabin baggage compliant, and the DS model is perhaps a little heavy to be considered portable under any circumstance. Fortunately a third option is available in the form of the FC-76 Objective Unit upgrade which screws in place of the FS-60 lens cell, to create the FC-76 DCU, a light weight and highly portable (because it splits) 3" f/7.5 refractor. It is also possible to create this model from scratch without having to purchase the FS-60. After several years of ownership, I have now written a review which you can find on the link below. This scope will be accompanying me to Africa on my honeymoon later this year and will no doubt provide some memorable stargazing experiences. http://alpha-lyrae.co.uk/2017/03/12/takahashi-fc-76-dcu-review/ The two components of the FC-76 DCU, the Objective Unit and Focuser Unit.
  15. My Takahashi FC-76 and Baader Herschel Wedge. Great combination.