Merlin

I have a mongrel solar ‘scope. A PST double-stacked with a Lunt LS50f etalon. It works, but it’s darker of course.

The thing about wobble is that the tripod can be more responsible for it than the mounting.

Put the mounting on a sturdier tripod or other solid base and we can sometimes  witness a transformation.

It used to be said that the way to remove dew from an objective is to put a warm handkerchief inside the dewshield and cap it for a few minutes.

I bought the Lidl refractor Year’s ago. The ‘scope’s okay on low to medium powers, but shows some astigmatism on higher powers.

I now use the ‘scope as a Stage 1 mod for solar viewing. For the money, the ‘scope wasn’t  a bad deal. I quite like the EQ2 mounting.

Vibration can be a problem in many ways. When my daughter was a child, she was in the habit, as many children are, of jumping from last few steps in the staircase onto the floor.

Alas, this habit ruined several LPs by making the stylus on the record player in the lounge jump across the vinyl, leaving pits and scratches on its surface.

What’s the aperture of your ‘scope Dave?

Many of the Newtonians we see today, including my own, have main tubes that are too short at the top, allowing a considerable amount of stray light to enter the tube and reduce contrast.

If we look through the drawtube and can see out through the top of the main tube ( ignoring the flat ), we need an extension. I made a foot-long extension for the 8-inched by rolling some camping mat material into a tube and lining it with Matt black art card.

The main tube extension fits like a glove and also acts as a dew shield for the flat. M anufacturers probably make the main tubes too short to make their ‘scopes look more compact, but this is at the expense of contrast and also makes the flat more prone to dewing.

I was lucky to obtain a superb ex- military mirror for my homemade mirror-mount. It cost just £3 on a flea market. It’s so good that I bought a second one the following week. The coatings are perfect.

Originally, the mirrors cost over two hundred of pounds each. They were well boxed and could be war surplus, which would make them very pricey on today’s money.

It’s been said that a well made, correctly adjusted, Newtonian reflector is superior to any folded-beam instrument.

My son lives on Jersey. I’ve never been, but he says that starry nights are superb there. There’s very little light pollution.

I remember in the 1950s when it was possible to see Uranus with the unaided eye from the centre of town. Alas, those were the days for stargazing... .

Put your secondary mirror on the end of a thin rod, the existing one must be causing a massive deffraction effect.

Some years ago, Jim Hysom at AE repolished a four-inch/f.12 Fraunhofer objective for me. He did an excellent job.

Bear in mind that if, at some point, you do a PST mod. it’s absolutely essential to have a D-ERF ( Energy Rejection Filter ) over the front of the donor ‘scope.
 Please don’t attempt a PST mod until you have all of the information you need.

I modded a 70mm refractor and it gives good results.

You won’t go wrong with Opticron. I have a pair of 8X40’s, very good.

We can hold X20 binoculars quite steadily if we mount them on a triangular frame with handgrips on the bottom.

I made a frame from aluminium tubing and it works well with the 25X70 bins.

I once witnessed a solar flare. It became intense white then faded, all in a few minutes.

It says iOptron Rumak  150 at the bottom.

The minimum magnification that can usefully be used on a ‘scope is about four times the aperture in inches. That’s X20 with your five-incher

It’s better if contributors to the thread say what kind of ‘scope they are using. Only one contributor has done this. Thanks. Stating the instruments used assists beginners and upgraders to know what to expect from a particular solar ‘scope.

There’s an easy solution to making a dovetail bar safe and that’s to file a slot on one side, so that the locking screw is secured in the slot.

It’s better if contributors to the thread say what kind of ‘scope they are using. Only one contributor has done this.

The Russians are planning to build rockets capable of  lifting 200 tonne payloads. So, there could be some  impressive space telescopes  launched in coming years.

Consider, too, a good spotting ‘scope. I have an Acuter 80mm diameter one with a zoom eyepiece. Being a spotter, it’s a general purpose ‘scope.

An good eight-inch reflector is a great ‘scope. Not too big and not too small to handle. It gives splendid views of many objects.

Back in the 1950s, I bought a long focus lens of about 50-inches from the H.W.English catalogue, which was a veritable Alladin’s cave of government surplus items. My interest in astronomy was fired by a little astronomy book in the school library, with the enchanting title “ The Star-Spangled Sky”, authored by a vicar.

The “ objective” lens was about three-and-a- half inches in diameter. It was very thin  like a big convex/concave spectacle lens. My dad, who had no interest in astronomy, made me a main tube ( no glare stops ) with a simple push-pull inner tube, a simple AltAz mounting and a tripod- all in cold steel at the local engineering firm where he worked.

The eyepiece, also acquired from the English catalogue, was a flawless big brass gunsight eyepiece, which I reckon yielded a magnification of about 50X. Aged twelve, on a warm summer evening while it was still light, I pointed the crude ‘scope at a gibbous moon. It was a revelation. I was astounded to see the lunar craters and mountains for the first time. This was followed by an overpowering feeling that I could travel anywhere in the Universe with my newly-acquired refractor.

Surprisingly, I didn’t notice any chromatism from the non-achromatic “objective”. This crude instrument inspired two friends to take up astronomy as a hobby. One made a four-inch reflector and the other a eight-inch reflector ( followed by a fifteen-inch reflector, but which was never completed due to him emigrating ).All the ‘scopes were fitted with bought out optics. Since then, I’ve never lost interest in our beautiful hobby.. .