CAN I USE MY TELESCOPE DURING THE DAY?

The obvious is observing and photographing the Sun.

It cannot be over emphasised that if you are a beginner - DON'T LOOK THROUGH YOUR SCOPE WHEN POINTED AT THE SUN.  KEEP AWAY FROM THE SUN. THE SUN WILL DESTROY YOUR RETINAS IN A FRACTION OF A SECOND AND YOU DON'T HAVE FAST ENOUGH REFLEXES TO PULL AWAY IN TIME. THE SUN IS OUR NEAREST STAR THAT HURTS YOUR EYES IF YOU TRY TO LOOK AT IT DIRECTLY, LET ALONE THROUGH BINOCULARS OR A SCOPE. WHAT WILL YOU SEE IF YOU LEAVE YOUR SCOPE POINTED AT THE SUN? YOU WILL SEE THE SCOPE GO UP IN FLAMES, SO DON’T BE ANYWHERE NEAR IT.

A few telescopes on Ebay are advertised with a sun screen.

This is a white screen on a bar of aluminium that you place a few inches (like 12 to 15) behind the eyepiece where you would normally stand to look through the scope. The bar slots into a screw-up holder. Tape some heavy black cloth over your finder scope and then point the scope at the Sun just by producing the smallest shadow of the scope on the ground. Then, you focus up to produce an image of the Sun on the screen, but the image will be very, very bright. OK for eclipses and sun-spots, but not much else. It will take about 10 minutes for you to recover from retinal nerve endings overload in the form of after-images of the Sun you see everywhere you look.

When you hear a sharp crack, you know that the build up of heat in your eyepiece has taken its toll. Cover the receiving end of the scope and leave it where it is for everything to cool down.

There are Sun filters available. My personal opinion is that the direct light and heat from the Sun should NOT be allowed to enter the telescope. That is why I have used an mdf disc with a 3 to 5 inch diameter hole cut in it over the front of my scopes. The disc must be firmly attached and incapable of falling off the front of the scope. The hole in the disc is covered with sun filter material firmly attached so that the filter cannot fall off (I used contact adhesive and a staple gun. When your eyesight is at risk, trust nothing and always inspect before using. An aperture of 4 to 6 inches maximum is fine for the Sun. Our closest star is very big and not that far away in astronomical terms.

Older filters are made of Mylar optical grade and give a blue image. The newer ones give a white image and cost around £14 for an A4 size filter. The light and heat transmission is a tiny fraction of a percentage of the light and heat falling on it. Every time you take out the mdf disc bearing the Sun filter, before you fix it in place, hold it up to the Sun and carefully inspect it for holes or damage. If there is any of this, throw it in the bin and get yourself another filter. The alternative is to risk blindness.

Be very afraid of sun filters that screw into eyepieces. If they shatter under the heat let into the scope, not only will your retina get burned, you could also get an eyeful of broken glass. There are also devices that look like a star diagonal. These are supposed to direct the majority of the heat and light out of the device and away from the eyepiece. Remember that any failure should be fail safe. Personally, I have never bought one and have never wished to.

The most ludicrous and criminally negligent design is the black Sun filter supplied with some Russian scopes, notably the TAL. It was designed by an idiot. It pushes onto the outside of the eyepiece and you put your eye up against it. Heat builds up inside the eyepiece and on the filter that can easily splinter a couple of millimetres from your eye.

If you have such a black filter, please don't try to rig any device to water cool or refrigerate it. Do yourself the biggest favour of your life. Put it on hard ground (like cement) and stamp on it at least twenty times. Doing that compels you to avoid the temptation of using it.

You want to know why the Sun is dangerous to eyesight? How does the heat travel through space (a near vacuum) to us?

98% of the heat is in the form of light. When light strikes an object, it heats that object. If that is not so, why does your skin feel warm in direct sunlight but not as much in the shade? Your telescope collects light and concentrates it to a point being the image. That image of the Sun is really hot and will burn paper in seconds. If it burns paper, what will it do to your eye?

WHAT WILL I NEVER SEE?

You must never, never expect anywhere near the same sort of results that the Hubble telescope has obtained. That one has a very big mirror and is above the atmosphere.

You will never ever see man-made things on the Moon. To see man made things on the Moon, you will need a magnification of about 63 million times. I'll leave you to work out the size of the mirror for that working at f/8 with a 4mm eyepiece.

You will not see the so-called canals on Mars because there aren't any.

You will not see black holes (if they exist) nor the planets in orbit around other stars.

Having said that, you will see literally scores of thousands of interesting things ranging from planets, stars, star clusters, nebulae and galaxies.

Last thing is this. A small telescope does not collect enough light for you to see the colours of nebulae and other extended objects. To image in colour, you will need an astro-imaging camera that plugs into your pc and overlays many images into its memory. Be prepared to pay around £200 plus for that. To see colours with your own eyes through your eyepiece, you will need a reflector with a primary mirror at least 15 inches diameter and colours are easily seen if the mirror diameter is 20 inches.

WHAT DIFFERENCE DO BLOOMING AND DIFFERENT COATINGS MAKE?

Traditionally, telescope lenses were not bloomed. Blooming is a coating of stuff put onto the surfaces of lenses to stop unwanted reflections. You can see these on many binocular lenses that appear red or some other colour. Blooming cuts down the transmission of light and that is not wanted. However, you will be hard pressed to find a mass-produced refractor that does not have bloomed lenses so please avoid red, green or other coloured up front main lenses. These are not sold by proper sellers of astro scopes.

Mirrors (main and flat elliptical) usually have the standard aluminizing (aluminium reflecting surface) overcoated with something that keeps out air to stop the aluminium coating turning grey. If the process of aluminizing is cheap and shoddy, the reflective coating will soon lift at its edges and then start to flake off, sooner rather than later if the scope is in damp air. There are a few good optical shops who offer an excellent service. Barry at Beacon Hill uses Galvoptics located on the Burnt Mills Industrial Estate, Basildon, Essex. Galvoptics will accept people as customers without any intermediary and the work they have done for me was excellent.

Standard coatings are the least expensive, about £50 to £100 depending on size. The reflectance of standard coatings is in the order of 86% but HiLux coatings show something like 97% reflectance, costs more and is more resistant to damp air.

If you have a Newtonian reflector and wish to keep the mirror coatings intact whilst it is in storage, it will not cost that much to improvise two stiff cardboard tube covers, one for each end. Then, keep an eyepiece in the focuser. If you want to get more complicated, attach to the inside of the bottom cover a small muslin bag containing silica gel beads dried in an oven for 30 minutes or so. Muslin bags are cheaply had on ebay from those selling kits for brewing your own lubrication you may need before you read the what can go wrong chapter.

SHOULD I BE THINKING ABOUT CLEANING?

Cleaning an up front lens in a refractor is dealt with later. If you wish to clean the main mirror of a reflector (you do get some dust and dead flies kicking around), you will find that nowadays, telescope tubes are not made with doors in the tube than open so that you can clean the mirror or get dew off it on damp nights. It means that you need a main mirror holder that unscrews or unbolts from the outside of the tube and comes out easily. But first put a small dob of paint or a pencil mark on the tube and the mirror mount so that once the mirror is cleaned, the mirror holder goes back the same way as it came out.

As to cleaning, no hose pipes, shampoos, soap that is gentle on your skin, vacuum cleaners, definitely no washing up liquid (you will get a salty deposit) and no chamois leather.

Gently blow (without spitting - not joking) on the mirror to get most of the muck off it. Then, use a good quality photographic lens brush for the rest.

If you did make a mistake and spit and have to use water, you must use distilled water or de-ionised water (not bottled water from the hot springs of Finland) because tap (faucet) water has dissolved salts in it that will leave filthy streaks. Distilled water is what you put in your car battery.

Try to clean the mirrors as infrequently as possible because the coating is very sensitive and is very easily scratched.

Your instruction book should have a section dealing with the care of the scope.

SHOULD I BUY GoTo?

A GoTo system is just a computer having a memory programmed with a star map. It is linked to the equatorial drive motors. You tell the computer your latitude on Earth and your local time. Then it clicks and burps before telling you it's ready. If you don’t know your latitude, download Google Earth, put the pointer on your house and read the latitude from the information given on screen.

Provided that your equatorial is accurately lined up on the North Pole of the sky, the computer will swing the scope around and point it at anything you ask it to point at that is above the horizon, but only if that object is in its memory.

That way, you don't have the bother of knowing the constellations and using a paper star map or a free star map download like Stellarium.

If you want one of these as an accessory, you will have to buy the one made for your equatorial mounting. Cost new, about £400 to £500, but you can obtain mountings with them already fitted. I have seen just 3 dedicated GoToos advertised on Ebay UK in the last year. However, the cheaper scope sellers offer these devices at very low prices consistent with the overall quality.

Thing is, if you have Stellarium on your pc screen and your latitude and local time are entered, it will tell you the coordinates of what you want to look at and you then set those coordinates on your equatorial mounting setting circles. There it will be. That assumes that you have the polar axis pointing to the Celestial Pole and the setting circles have been set by you. Not that difficult once you have done it a few times.

THE THING ABOUT GOTO IS A BEGINNER DOES NOT NEED TO LEARN CONSTELLATIONS, EQUATORIAL COORDINATES AND MAYBE GET VERSED IN SOLID GEOMETRY. JUST GET A BOOK ON ASTRONOMY WITH A LOAD OF WONDERFUL PICTURES (USUALLY TAKEN THROUGH SOME HUGE AND PROFESSIONAL TELESCOPE IN AN OBSERVATORY) AND TELL THE GOTO THAT IS WHAT YOU WANT TO SEE. THE SCOPE WILL SLEW ROUND AND TRACK ON IT IF THE OBJECT IS ABOVE THE HORIZON.

ARE FORK EQUATORIAL MOUNTS BETTER THAN GERMAN EQUATORIAL MOUNTS?

A German mount is not from Germany. It is only the name of the mounting. You could easily call it a 'Joe mounting' instead.

A fork mounting holds the scope between two uprights and is used by Meade, Celestron and a few other manufacturers. Forks do not need counterweights except maybe to balance the length of the tube if you are using a heavy camera and an eyepiece projection unit.

Unless the scope is fairly big and the forks are widely separated, you may find it awkward to point the scope at your zenith (straight up) and get your head into a convenient position in the vicinity of the eyepiece.

A German mounting will swing around from zenith to horizon and do a 360 degrees around the horizon without the same difficulty but unless the tube is rotated in its holder, the focuser can end up in an awkward position for viewing. That is often the reason why Ebay sellers say that the telescope tube has some marks and scratches.

ENOUGH OF ALL THIS WAFFLE. WHAT YOU WANT TO KNOW IS IF THE TELESCOPE YOU THINK LOOKS GOOD IS WORTH PAYING FOR AND WHAT YOU SHOULD PAY FOR IT. THOSE ARE DEALT WITH IN PARTS FIVE, SIX AND SEVEN.

THERE IS ALSO SOMETHING ELSE. ALONG THE SAME LINES, IF YOU HAD ONLY JUST PASSED YOUR DRIVING TEST (AND MONEY WAS NO OBJECT), YOU WOULD HARDLY START DRIVING IN A BRAND NEW FERRARI OR PAGANI ZONDA. REASON IS, SUCH CARS WOULD OVERWHELM YOU BUT WOULD BE OK ONCE YOU HAD A COUPLE OF YEARS EXPERIENCE IN 'LESSER' CARS. SAME THING WITH TELESCOPES. YOU REALLY DON'T NEED A TOP CLASS STATE OF THE ART PIECE OF EQUIPMENT IF YOU DON'T KNOW WHERE TO FIND THE NORTH CELESTIAL POLE AND SAY THAT BETELGEUSE WAS A VERY STRANGE FILM STARING MICHAEL KEATON.

THEREFORE, IF YOU ARE A BEGINNER, A PAIR OF 7 X 50 BINOCULARS IS IDEAL (NOT 8 X 60 OR 9 X 50 OR 10 X 30 ETC.).

IF YOU HAVE ALREADY HAD A YEAR OF STARGAZING EXPERIENCE AND ARE COMPLETELY 'HOOKED', SOMETHING LIKE A 6 INCH REFLECTOR OR A 3 OR 4 INCH REFRACTOR FROM A REPUTABLE MANUFACTURER.

IF YOU ALREADY HAVE ONE OF THOSE, THE PART DEALING WITH UPGRADING IS FOR YOU.

REPUTABLE MANUFACTURERS. THIS IS JUST MY OPINION BALANCING QUALITY AGAINST PRICE :  PHENIX REFRACTORS (CHINA - NOT PHENIX REFLECTORS), ORION (UK), DAVID HINDS (UK), CELESTRON, MEADE (BOTH USA).

GETTING MORE EXPENSIVE : TELE-VUE, ASTRO PHYSICS (BOTH USA), SINDEN (UK), TAKAHASHI (JAPAN).