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2010-11-06

M45: The Pleiades

The Pleiades or Seven Sisters, number 45 in Charles Messier's catalogue of nebulae is a well known asterism and nebula in the constellation of Taurus (the Bull) and is visible in the autumn and winter skies. I took this image at the end of last year in Langkawi in Malaysia.

The Pleiades


Olympus ZD-150/2 lens @ f/2.0 on E-620. Kenko SkyMemo-R mount. Pre-processing in IRIS, post-processing in Photoshop CS5.

I'm still learning how to process images. It's hard.

2010-11-05

Things are Awesome

So a couple of weeks ago I was sitting have breakfast and browsing the web on my iPad, when the (free!) 3D Sun app decided to interrupt to tell me about a large Coronal Mass Ejection on the Sun. I then switched to this app and was able to see photos of the Sun, in various wavelengths including X-rays. These photos come from STEREO, which allows us to see more than one side of the Sun. I was also able to download videos of the CME.

Think about that. I got notification of a huge event (and I mean huge - many times the size of the Earth) on the Sun that we didn't even know about until relatively recently. I'm not some astrophysicist at NASA or another national space agency, I"m not even a researcher in astronomy in general. I'm just a guy with an app. An app that allows me to see videos in fecking X-rays of the Sun. The views from the telescopes on two spaceships are automatically combined to form an image on a globe that I can rotate and look at as a 3D object. All of this while sitting at home drinking coffee and eating toast.

How awesome is that?

I am typing this on my new (shiny shiny) MacBook Air, while my Roomba (a robot) is hoovering the apartment. The Roomba  does this everyday at 8:00am and then goes back to its charging bay ready for the next day. You probably didn't stop to think about the "browsing the web" phrase in the first sentence. From my computer I can keep up with events and current research from all over the planet, see videos and photos from that people I don't know from all over the world. Likewise I can easily share photos and videos. In addition, I have available to me a large portion of the world's knowledge (for good and bad). I can do all this while enjoying a coffee without leaving my chair.

How awesome is that?

Not only can I do all of this, I can look forward to a much longer, healthier and happier life due to improvements in medicine and healthcare.

This is a few examples of "teh awesome". This is the best time to be alive.

Yay for science, yay for engineering, yay for geeks.

We're screwed when Peak Oil kicks in, though.

2010-10-25

Hillis Plot

In case you've not yet come across the truly awe-inspiring Hillis plot from the group at UT, here it is: http://www.zo.utexas.edu/faculty/antisense/DownloadfilesToL.html

There's a blog entry with a good description here.

"The Catsters" videos organised

The excellent youtube videos by "The Catsters" organised by Edsko de Vries at UCD: http://www.scss.tcd.ie/Edsko.de.Vries/ct/catsters/

2010-09-20

AR 1108

Active Region 1108

Some basic processing with some frames captured this morning.

Seeing: III

Equipment: LOMO Astele 133.5 @ f/10, DMK21AF04, Baader white light solar film, IDAS LPS-V4, Kenko R1 Pro, Takahashi EM-200 T2Jr

Processing: Astro IIDC (capture), Keith's image stacker (align, stack), PS CS5 (post-processing), no wavelet processing

2010-09-02

Baader MaxBright T-2 binoviewers

Initial Impressions & Thoughts


This post was initially a response on a singastro forum, but was so long, I thought I may as well blog it.

From Teleskop Service in Germany, I bought:

  • The Baader Maxbright binoviewer kit with 1.25x glass path corrector and 1.25" nosepiece.

  • Zeiss Jena 90 degree prism T-2


This is the first time I've used Teleskop Service. Good prices, easy to use site, same day shipping and everything was packaged well. Very happy with their service.

From Starbase in Tokyo.

  • 2x 18mm Takahashi orthos (24.5mm)

  • 1x 12.5mm Tani ortho (24.5mm). I already have another 12.5mm


Great service as per usual.

On opening the binoviewer and parts


The binoviewer is nicely made, with coatings well applied. The tension is just right, and there is a fair amount of focus travel for each eyepiece. The helical focussers for the eyepieces are smooth. On the prism, however, I was surprised to see a tiny chip on one surface. I doubt this will have much, if any effect, but still, I'd expect it to fail QC, especially with the Zeiss prism being the more expensive option. There is a plastic ring on the male threaded side of the prism. This ring is there to provide some gradual pressure when you tighten the thread, and worked well with some T-thread accessories I tried. However, to fully screw the prism to the binoviewer, I had to remove this ring. Without the ring the binoviewer jams and "gives" suddenly. This is a bit disappointing.

Also, there is the usual Baader problem of 'sticky' threads. Every Baader filter I've ever had has had the threads very slightly off. Not sure why this is, but again the prism and binoviewer have this problem.

The 31.7->T adapter is well made and has a 34mm thread internally to attach the glass path corrector. This works well.

First light


Of course it was cloudy when I got all the parts delivered and I couldn't try them out on the sky. I just looked at some far-off buildings and lights. So, these are fairly useless initial impressions.

I tried the binoviewer and prism on my FSQ-85ED, which has a lot of back-focus (>200mm) to support long imaging trains. The adapters for visual use take up some of this, quite a bit as it turns out.
There are basically two configurations:

  1. Binoviewer - corrector

  2. Binoviewer - prism - corrector


With 1, I could get focus with the 18mm orthos. But with a Televue maxbright 1.25" diagonal inline I couldn't get focus.

I then tried configuration 2, and couldn't get focus. I changed the Tak 2"->1.25" adapter set (which takes up about 30-40mm or so) to the low profile adapter, and was able to get focus. There was quite a lot more back focus available when using 31.7mm eyepieces, so I could probably just use the normal adapter. This setup is close to the stated requirements.

  1. The quality of the machining shows - I had no problem fusing the image and getting good focus for each eye

  2. Very nice, high contrast, sharp images

  3. Some lateral colour

  4. Some softness at the edge of the field

  5. Internal reflections


By far the worst and most intrusive was 5: internal reflections. This was very, very bad. Far worse than any I've seen in cheap binoculars. In daytime viewing, this will probably lead to reduced contrast. It's probably not much of an issue when viewing star fields, but these reflections will probably cause problems viewing the Moon. These were so obvious and so bad, I'm curious if there's something weird about my setup. I can't think what it would be - they were visible with or without the prism.

Point 4 is worrying, but I need to try this setup under the stars to see what's going on. There's certainly no field curvature on the Q, but it's possible the light cone is still a bit too steep for the orthos, or even the prisms.

Some things to heed:

  1. The Tak 31.7->24.5 adapters are nice, but take up even more back focus. DOH. So, don't do what I did. Use 31.7mm eyepieces.

  2. The Baader T-2 prism allows you to connect the binoviewer with the minimum increase in light path. I'd recommend this, or another T-thread diagonal.

  3. You will almost certainly need one of the glass path converters. Unless you're using something like a Borg, Tak Sky-90/Q or other scope with a lot of back focus, you will need a corrector with magnification higher than 1.25x.

  4. The entire setup is quite heavy and greatly increases the moment on the rear of your scope (assuming a refractor or compound).

  5. Due to the weight, you're not going to be able to use heavy eyepieces. If you want to do this, it would make sense to do so on a larger scope and get the more expensive Mark-V binoviewer.

  6. I've not tried the setup with my Mak or Mewlon yet, but I'm worried about the ergonomics. It looks like the scope might get in the way. There is a 45 degree Amici prism that may be more suitable.

  7. Eye placement seems to be more critical than with a single eyepiece.

  8. SCT owners are going to focus way, way off from where the system is optimised. Expect even worse off-axis performance than usual, and probably some SA on axis.

  9. The system diagram I got was for the older binoviewer system which was not T-2. There are some configurations not possible with the T-2 system, and others that are no longer necessary. This might lead to confusion.

2010-08-08

Borg 71FL is pretty damn good

Here is a post with a photo that shows some Fresnel rings. I need to do a proper Roddier test, but it's looking pretty good.