Thursday, 30 April 2009

Starting to guide

My next adventure in astronomy is to start guiding, so that I can improve my photographs and really nail some good images.
I began the usual trawl of looking on the tinterweb for what was available to use to guide my scope and give me the stability in my images.

The choices for guiding are clear it would seem, you either sit in the CCD or webcam camp, now there is no questioning the brilliance of CCD (Charge Coupled Device) technology, producing high quality imaging and is a superb tool for guiding, with guiding CCD's able to plug directly into the guidescope port on your mount even, and guide the scope direct.

But CCD comes at a hefty price tag, with even a cheaper end guide camera coming in at around £150 without software. I simply cannot run to this at the moment, but hey, everyone has a webcam!

I have a Logitech Quickcam S7500, which works fine on my Macbook Pro, this coupled with the superb Keiths Astro Imager and I was set, the software recognised the webcam instantly and I was able to easily take images and use Keiths Image Stacker to produce an image of my office, Keiths Astro Imager also guides, so I was really pleased.

The last mountain to climb was a big one it seemed, as the world of astronomy is very rightly focussed on the rarer than hens teeth Phillips SPC900 and Phillips Toucam webcams, and therefore converters and extensions to couple your webcam to a 1" 1/4" are largely focussed around the afore mentioned excellent cameras.

So what to do? well it may be a little known fact but an old 35mm film case will slip very nicely over the end of an eyepiece, well my eyepieces anyway, if you take of the rubber eyecup you can easily pop the film canister on the end and it will stay put very well, excellent! Now how to attach the webcam to the canister. This is even less basic than the other end on the eyepiece. Cut the end off the canister and fix it to the webcam with the lens centered. On the Logitech the canister slips onto the front really well and even lips over the lens housing with a rather satisfying little click, a smear of silicone around the outside to hold in place and I was done.

This is obviously not as robust as the bought and purpose made adapters but I don't really care, it was easy and it works.

Results to follow, as well as images of the modded cam.

Wednesday, 22 April 2009

Imaging Saturn - First go

I watched the weather closely all day yesterday, hoping that the evening would bring one thing, no cloud. Luckily I was pleased to see a warm, clear evening unfold before me. By 8pm I had my CG5 outside and pointing North ready for my first ever try at imaging a planet, the sun set and I waited very nervously for Polaris to appear so as to begin my alignment. Using my polar scope I carefully set up the already leveled mount and followed my same procedure for polar alignment, checked and re-checked then added my scope, and balanced, lastly putting on my home made dew shield.

I powered up the Goto and began 3-star alignment, this is where the trouble began for me, as for some reason my Goto had spat out all of it's PEC and tracking data, the scope slewed around totally incorrectly and my heart sank, I had crowed over Twitter about how I was imaging that night and it was going to be great, and now here I was, Goto giving me trouble and the most wonderfully clear, dark canopy above me.

I was relying on the Goto's tracking to give me the stability for my first go at imaging planets, my Celestron sat and looked at me blankly, as if to say, it's not my fault, I have not done this to annoy you!! Me and my Goto had never seen eye to eye, but we had an understanding, but tonight it was rebelling.

So what to do? well, resigned to the fact that I will not be having the best of times tonight with technology I swung my scope to Saturn and attached my Nikon D40 at prime focus and decided that I would see what happened.

The first thing that strikes you is of course that with just a T-ring and adapter in place, distant objects such as Saturn, do not appear very large in the viewfinder of the camera, this of course makes focussing a real issue, but I fired off several images to see how we got on, not well is the answer, the image was out of focus and because of the length of exposure (around 10secs) Saturn appeared as a nice white teardrop on the viewfinder, even Saturn was sad to see me.

But I persisted and I learnt very valuable lessons last night, the main one of being just how much I still don't know, but it also filled me with such inspiration to continue to try to get a good image. I simply wont be buying a CCD as the price goes beyond what is "Amateur" to me, but my Nikon D40 is a superb camera, and I don't doubt it's capabilities to produce the images I desire, my 6" Celestron Schmitt Cassegrain is also well up to the task. As with all things operator error is the failing.

It did make me appreciate the level of work that goes into producing the images we see in magazines and on the net, and also the sketches that people like @Space_Jockey produce, the attention to detail is mind boggling, hopefully Space Jockey is planning a tutorial of his methods, you should check them out at his blog.

I'm off to read a little more, practice a little more and continue my absolute passion for Astronomy, and whether you rate the images or not I love them.

So get outside and give it a go, take a picture of the moon or stars, your recording an amazing world of beauty and violence as stars explode and are born, can you tell I like this yet?


Monday, 20 April 2009

Campaign for dark-skies

I'm sure most people are aware that dark skies and astronomers go hand in hand, but are you aware of just how high the amount of light pollution is getting these days? Well check out the picture below taken from the Campaign for Dark-Skies website

This shows the amount that light pollution has increased over the last 50 years in the city of Bath. Now there seems to be an argument over darker areas and safety, which I can fully understand, but look at the image at the top of the blog, thats the nigh time view of Telford.

What is the need to allow so much light to escape into the night sky? A fine example of how light pollution can be kept to a minimum is the Qatar race circuit, this race track is lit, and suitable for Moto GP racers to use at night, just look at the way the light is diffused just onto the track.

I can see that this is an expensive task to achieve, yet surely there must be someway to pass on this technology to suburbia? Think of your outside lighting, do you just illuminate your garden or the rest of the neighborhood as well, do you really need 500 watts to see?

The following are the aims of the campaign for dark-skies;

CfDS wants to to see:

  • Greater use of modern fittings which control the light emitted, to minimise sky-glow and light trespass.
  • The right amount of light for the task, not wasteful over-lighting - Sensible wattages (a 40W light will adequately illuminate the average driveway and garden) up to a maximum of 150W;
  • Controls on floodlighting of buildings, sports facilities, etc., with appropriate shielding, baffles and mounting adaptation causing lamps to shine preferentially downwards;
  • Instructions about sensitive mounting, and information about light trespass and other possible adverse effects, in packaging of all exterior lights.

CfDS believes that:

  • Astronomers have the same lighting needs as everyone else;
  • Street lights should NOT be turned off, but well directed to illuminate just the street;
  • Everyone should have the right to illuminate their premises at night if they so wish, as long as it does not intrude into neighbouring properties;
  • Lamps used should comply with Institution of Lighting Engineers' guidelines (revised 1994), with 150W as a maximum value for typical domestic and small-scale commercial premises;
  • In the absence of proper regulation of light, which is as much of a potential pollutant as noise and other impactors, retailers should take the lead in preserving a night-time environment showing a balance between good quality lighting and enjoyment of that night-time environment;
  • The promotion of outdoor lighting should concentrate on aspects of visibility and careful lighting, rather than making debatable claims about crime deterrence and links between brightness and effectiveness;

CfDS points out that:

  • Minimising light pollution saves precious energy resources. The amount of greenhouse gases released into the environment by power stations can be reduced.
  • Well designed light sources emit little or no light above the horizontal. Unshielded lights may, depending on the design, emit well over 50% of their output above the horizontal.
  • Glare from roadside lights, as motorists know too well, is another result of poor design, and is distracting when driving.

Sunday, 19 April 2009

Astronomy sods law

As most of you are aware there is a rule in astronomy, it states; "Should you buy any new item of equipment for the use of looking at the stars, an obligatory period of cloud will ensue, the amount of cloud is relative to the amount spent".

I spent £27 and I have had 3 days of cloud grrrrrrrr!!

Saturday, 18 April 2009

Saturn - Some facts

With Saturn still very visible in the night sky at the moment, I thought a few facts, ten in fact would be appropriate.
  1. Saturn is the second largest planet in the solar system. It is so big Earth could fit into it 755 times
  2. Saturn is a slightly smaller version of Jupiter, with similar, but not so distinctive surface patterns. It's only main difference is those completely stunning rings
  3. Saturn's rings could well be particles of an moon that used to orbit the planet, that was drawn in by Saturn and obliterated
  4. Saturn's rings orbit the planet at different tilts, sometimes they can be very visible from our viewpoint on Earth other times they appear edge on, this edge on view occurs about every 14 3/4 years on Saturn's orbit around the sun, and as the rings are only approx one mile thick our 800 million mile away view makes the rings seem to disappear for a while
  5. Some astronomers believe that one day the rings will disappear altogether, They will either disperse into space or get sucked into Saturn by it's gravitational pull, this could happen in around 50 million years, so don't worry about it at the moment
  6. Despite it's similarities to Jupiter, there is no great spot on Saturn, (Jupiter has an area called the Great Spot, which is a storm that has raged for many many years) but Saturn does have stormy weather
  7. Saturn is twice as far away from the sun as Jupiter is
  8. Saturn's largest moon, Titan, is the only moon in the solar system to possess an atmosphere
  9. Saturn has such a low density that if we had an ocean big enough here on Earth, it would float around on it - in comparison Earth and Mercury would sink the fastest
  10. One year on Saturn would take almost thirty years on Earth, but a day on Saturn only lasts about ten and a half hours

Ever wondered what Saturn means? well Saturn was the Roman God of agriculture. It's Greek equivalent would be Kronos.

What about Saturn's weight, well I'd ask you to guess but it might take a while, Saturn weighs
568,510,000,000,000,000,000,000,000 kg - So maybe another cream cake for Earth.

Saturn still remains the one planet, in my opinion, that gets the biggest "ooooghs", it remains my firm favourite with the moon a close second (sorry @Space_Jockey) I love it's moons, and the shadows that they cast on the Gas giant that is Saturn, Saturn evokes real passion and a sense of wonder, and the realisation in people that you are looking at a real planet, it kind of puts you in perspective as to your place in the universe.

Friday, 17 April 2009

NASA images

One of the most beautiful pictures that I have seen in a long time is this one from NASA. It shows an image of colliding galaxy clusters. How can anyone ignore the amazing beauty of this, and it's right there above us for all to see. See the bigger picture here.

Thursday, 16 April 2009

Saturns spokes

Bright spokes on Saturn's rings

Bright spokes emerge from behind the shadow of the planet and into sunlight in this view from the Cassini spacecraft.

Saturn's long shadow covers the left side of the image. This view looks toward the sunlit side of the rings from about 22 degrees below the ringplane.

The image was taken in visible light with the Cassini spacecraft wide-angle camera on Feb. 26, 2009. The view was acquired at a distance of approximately 821,000 kilometers (510,000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 150 degrees. Image scale is 46 kilometers (29 miles) per pixel.

With thanks to NASA for wording and image

Binoculars - A good start

As I have mentioned before a great place to begin your astronomical hobby is with binoculars, but do you actually know what it is you are looking at when the nice salesman is telling you about them being nitrogen filled and that they have a zoom ya de ya de ya, total discombobulation (thanks to K for the word of the day).

So lets start with a nice basic thing that you'll want to know, what is the magnification of the binoculars that I'm looking at, what does it all mean? Binoculars are commonly described by using a pair of numbers that just look like a maths sum on the side, it's the number you look at and go "oh yes", like you know. You'll see it represented like this; 7x50 or 25x50 or any other kind s of numbers. This is really incredibly simple, the first number represents the amount of magnification that the binoculars offer so in the case of the 7x50's the 7 means that whatever you look at through the eyepieces will appear 7 times closer than they would to the naked eye. See told you it was simple, the next bit is just as easy to understand so don't worry.
The 50 in the 7x50's relates to the size of the lens, or the big bit of the binoculars, the objective lens as it's commonly called, so the 50 stands for 50mm,

The objective lens is very important to you if you want to use the binoculars astronomically, as the bigger the lens at the end, the more light that you can catch, the better you will see in dim light. One important thing to remember is that everything through binoculars is magnified, which includes your own movements, so any shakes or wobbles will also be very noticable, so the higher the power the harder it is to hold them steady, and if you are using 50mm or above the binoculars will also be slightly heavier than smaller ones, this again adds to the problems of holding them steady.

So now you know the magnification and the objective lens diameter you can do a a calculation that will tell you the exit pupil, why is this important you ask, well it's a bit to do with how old you are, no I have not gone totally nuts, as you get older your pupils shrink and so getting a pair of binos with a huge exit pupil may not be worth it to you if you cant take advantage of them, with this in mind the formula is this. Divide the objective lens size by the magnification and this will tell you the exit pupil size so with our 7x50's you get approx 7.1mm of exit pupil, so 7.1mm of light is transmitted to you pupil. A bit techy but maybe important to you.

The next thing that you will probably come up against is the lens's themselves, you turn the len's towards you and are greeted by a lovely coloured lens and you think "ooooooogh, pretty", but beware, amber and red coatings are an astronomical no-no, they seem to be a bit of a gimmick to hide poor optics, but are said to be to reduce light glare.

The prism will be your next area of attention, the prism is what lets you see a correctly oriented image when you look through the binoculars. Typically there are two types of prism, Porro prisms and roof prisms, what's the difference though?

Porro prism can be identified by their offset tubes, so the objective lens is not in line with the ocular lens, or eye piece. The eyepieces are usually closer together than the rear lens's, but the reverse can be true in compact models. Porro prism are usually much better quality than roof prism another benefit is that they have a single pivot between the two halves of the binocular, making then easier to adjust to your eyes. Porro prism are also described as Bak4 or Bak7, with Bak4 actually being the better quality, and therefore the ones to go for if possible.

Roof prisms are essentially in line inside the optical tubes, and therefore can make for a more compact set. Roof prisms usually have two pivot pints between the two halves of the binoculars, and are more difficult to adjust to your face. Roof prisms can give an optical image equal to Porro prisms.

Another thing to think about is dewing of your lens's, when your outside and the night is cold, and you bring out your lovely warm binoculars from their brand new bag, the difference in temperature between the outside air temp, and the binocular temp is likely to cause one thing, dewing, this will end your observations very quickly, so consider getting nitrogen filled binos as they will not suffer from this problem at all, my own binoculars (15 x 50 in case your wondering) are nitrogen filled and I have never known them to mist, they are also waterproof.

So what to do to choose, well heres a few things you can do to test them in the shop;
  • Steer away from zoom binos, there has not been a decent zoom made EVER (yet)
  • Steer away from Red or amber coatings
  • Give them a bloody good shake, if they rattle, don't buy them
  • Check the focussing through its entire range, reject any with loose spots or that bind whilst focussing
  • Do the same check with the focussing for the right eyepiece adjustment
  • and check the hinge is also smooth
  • If you re going to use your new binoculars with spectacles then make sure you can see properly through them with the eyecups folded down and the binocular at spectacle distance, so about 25mm
  • If you have a big nose make sure it fits between the binoculars
  • Check what prism you are buying, remember Bak-4 are best in my opinion
To see just what can be achieved with a monster set of binos, the look no further than Space Jocky he uses a set of Strathspey 25 x 100's (see pic at top of post)

Now these are some big binos, and will only be used on some form of tripod or support, but the results that you can get with them speak for themselves, check Space Jockys site for cracking images.

Follow Space Jockey on his blog or on Twitter, he really is an expert when it comes to using binoculars.

So I hope that helps a bit and good luck with any purchase you may make, and if you do, tell us about it.


Wednesday, 15 April 2009

Virtual Telescope - Bellatrix Observatory

Not to be missed is the Virtual Telescope Bellatrix Observatory in Italy. Gianluca and the team are amazing, prices are very reasonable approx 50 Euros for 5 hours. The images that are available from this link are the images taken during the 100 hours of astronomy session, where many of us joined Gianluca in a truly memorable event. The first image of Saturn that is displayed is the one I took during my session.

Beginning Astronomy

So you've seen a shiny new telescope in a shop, borrowed a set of binoculars and looked at the moon, and now you think that you're ready to take the plunge and get that scope. Well firstly STOP!!!!!! my advice is to truly understand what it is that you are about to undertake, and stick with the binoculars for a bit, Space Jockey uses a set of 25 x 100's and is able to view just as much as a lot of people with a scope, why? because he knows how to use them and what to look for, he sees nebula as well as star formations, check out his blog here.

If your still hooked after a little binocular dabbling (and you will be) then if you want to, plump for a scope, but, which one? Reflector? Refractor? Dobsonian? Matsukov? Schmitt Cassegrain? the list is endless with each scope being good at something, but not good at all things. One thing to remember is that the bigger the aperture the more light you can gather, the better you may see, with this in mind Reflectors are good value for money, they provide the biggest aperture for your money. But they can be big and difficult to move about, bear in mind the bigger it is and the more it does, the more likely it is to stay put away, as it's so much hassle to get out and set up. Reflectors are relatively inexpensive and can be bought for around the £100 mark.

Mount is another consideration as the one you buy could be critical to your enjoyment, up and down, side to side (Alt Az) or Equatorial? What a decision to be faced with, equatorial follow the arc of the sky and can be very accurate and easy to use, once you find out just how to use them, Alt Az is in my opinion easier, but not what you want in my opinion if you want to advance in the field of astronomy.

So what did I buy when I first began this obsession? Well as I mentioned I got a pair of binoculars first a pair of 15 x 50 and I was hooked. I looked at the Moon and saw so much detail, I had a bit of a moment you might say, I then purchased a book that I would recommend to anyone starting out, it's called "Turn left at Orion" and will teach you the sky and how to star hop, so as to know where you are, and more importantly, what you are seeing. Once I had the hang of that, something which took a time I might add I began the trawl, you know the one where you read everything and talk to everyone about telescopes, but still are unable to make up your mind as to which one to get.

Everyone was more than happy to explain to me their personal preferences and as to why they had made that purchase. I first leant towards a Dobsonian, I like the simplicity and the sheer size of the scope, but I new that I wanted to image the sky and that a Dobsonian would not suit the way in which I wanted to do it, I then thought I'd go straight to the reflector good scopes with plenty of punch and more portable than the Dobsonian. But I still could not make up my mind, all the scopes had their pros and cons.

Finally I turned to what I already know, photography. This led me to take a closer look at the Maksutov style of scope as they are basically to me a large telephoto lens on an equatorial mount. But which one again, so many to choose from so little money. I then spoke to the good folk at David Hinds I explained what I would like to do and they steered me towards an offer they had on at the time. I am now the very proud owner of a Celestron C6 XLT Schmitt Cassegrain, and as you can see in the picture at the top of this blog it resembles a big DSLR lens. I bought it because it was an excellent price and is kind of a jack of all trades if there is such a thing in the telescope world, it produces me superb images of planets and nebula, and Im over the Moon with it, if you excuse the pun.

So to conclude, my advice, check around, but speak to the experts, it's a lot of money to be disappointed about spending, and look through as many scopes as you possibly can, each one is different in it's capabilities. Get the best mount you can afford, it's very important to have a steady base for your scope, and a good mount will be able to take all those upgrades and new tubes you no doubt will eventually get.

Also remember that whenever you buy anything that looks at the sky, after you have bought it and are eager to get out and use it, the sky will automatically cloud over for the following weeks.

Good luck, and clear skies.

T adapter ordered

Yes! ordered my T-adapter and T-ring today from Steve at First Light Optics, hopefully use it to image over the weekend and post my results, bet there terrible for a while, but here goes.

Follow me on Twitter

You can also follow Starmunchers on Twitter, my name on Twitter is craiggold I don't use the Starmunchers name as I reserve that just for here, and using my name is a bit more personal, drop me an @ and say hello.

Spring Moonwatch

For those that took part in the Spring Moonwatch I have enclosed my favourite picture from my efforts during the fabulously clear weather that seems to accompany the lunar transit. I hope you all took time to get outside and take a look at the moon and try to spot it's features. Even a cheap pair of binoculars will show you some detail, try it for yourself, go outside and look up.

Thanks to AstronomyRocks

Here we are with the first blog on the first day of Starmunchers, I wanted to start by thanking AstronomyRocks for the advice on Twitter as to which Blog to use, it was a toss up between Blogger and Wordpress, and seeing as I could not understand Wordpress in less than 30 secs I went for Blogger and here we are. Anyway make sure to check out AstronomyRocks on both Twitter and on their blog.