RobH

I had an ST120 for many years. It's a good basic scope for widefield views, and the eyepieces it came with, and the diagonal ( a 90 degree one, not 45 degree erect image one which you will need for terrestrial views) were fine....not the best by any means, but fine for starting out. Trying to get decent results at higher magnifications than you can get with the supplied 10mm eyepiece is a waste of time. It's a basic achromatic short focal length lens, and these sufferfrom chromatic abberation and can only take so much magnification before the image becomes a blurry mess.

Don't get a barlow with it.....the last thing you want is more magnification. Used for what it's designed for, widefield views of star clusters etc,  it's a great scope for the price, but if you want high magnification views of the moon and planets, then get a Mak or similar, as has been suggested here earlier.

Just come across this, and all I can say is that this is, by a country mile, the best piece of astrophotography I've ever seen......staggering gentlemen!!

Fantastic image. Easily the best I've ever seen of M31......you've raised the bar not by an inch, but a mile :-)

What a sad day.

Even though he was obviously very frail and this day was inevitable, I still feel like I've lost a member of my family, and, I suppose we all have.

I truly hope he gets his wish and is reuntided with the fiance he lost in the war.

One of the few truly great people of our era and an inspiration to many many thousands of us over the years.

RIP Sir Patrick

Very tempting. I was looking at the Televue one for my TMB80/480 but it's well over £200....if this one can do the job, great!

Rob

Superb Olly

I knew there was nebulousity around Betelgeuse, but haven't seen anything like this before.

Cheers

Rob.

Hello all.

I've just updated my website with a few primers.....follow this link to the relevant section...

http://stargazerslounge.com/imaging-tips-tricks-techniques/121457-articles-tutorials-signal-noise-image-calibration-levels-curves.html#post1602671

Cheers

Rob

Another trick is to nudge the mount to the north before starting calibration. The first DEC calibration command is North and doing this takes up the backlash. With my old LX200, DEC calibration would sometimes fail if this wasn't done.

I suppose the same applies to RA, but I never had any trouble with this and can't remember which direction the first calibration move is.

Cheers

Rob

Not less than 1.5 x the diameter Rik.

Cheers

Rob

The only gaffa tape I had available at the time I made mine was white, and I wasn't terribly neat either!

I keep meaning to make new ones and cut everything to shape, but for now they are all 'swiss rolls' in grey with scruffy white gaffa :D

I shelled out and bought a commercial one for my 14 inch....it was rubbish. It was heavy, flopped about and didn't fit well....and it cost £40

The camping mat I replaced it with was vastly better, and I made it so it'd fit the various accessories on the front of the scope, which the commercial ones don't do.

All my scopes now have scruffy looking but highly effective camping mat dewshields held together with gaffa tape....I don't care what they look like, just how effective they are.

Cheers

Rob

Not only a fantastic work of engineering, but a piece of art too

I vote pic of the week too....amazing job, I'd love to look through it.

Cheers

Rob

Hello Rossco.

I got them from a company called universal cables.

I got the highest spec I could...why mess around.

I think it came to a shade over £20.

Here's a link to the page....

Cat 6a Patch Cables, Cat 7 Shielded Cable

Cheers

Rob

Are you using the cat5 cables supplied with the mount?

There have been issues reported that sound similar to this by those using these cables.

When I bought a CGE, I immediately replaced the cables with the best quality ones I could get....cat 7 cable and gold plated connectors...a bit longer too.

Try swapping the cables. If it is a cable fault, it may well then cause the DEC to be OK and the RA to have a problem.

Cheers

Rob

The eye isn't sensitive to colour at low light levels...next time you go outside when it's getting dark, watch and see how quickly everything becomes greyscale.

There are very few deep space objects (DSO's) that it is possible to see in colour, even in the largest scopes...M42 is one, and M57 is reortedly another.

I've heard that you really need a 36 inch scope and above.

The colour you see in photographs is the result of very sensitive detectors being pointed at the same area of sky for many hours.

Re. magnification. The higher the magnification, the smaller the area of sky that you're looking at. Something like M42 is actually quite large, so at high power you will only see a little of it.

Also, the more you increase magnification, the dimmer the view becomes, meaning that for higher powers, certainly with DSO's, you need a bigger scope to gather more light in the first place.

Actually...higher magnification increases contrast, not the other way round.

The reason is that, especially in areas of light pollution, the background sky glow becomes less of a problem at higher power, as you are seeing less of it. The reason it can seem to decrease is the loss of light I described.

The other thing about high power is that it depends very miuch on the atmospheric conditions (seeing). If the seeing is bad, high powers will just show you a wobbly mess, where a lower power will give a better view.

The general rule of thumb is that, with a good scope and the best seeing, 50x per inch of aperture is the most you will get out of it, 30x being generally more realistic.

Hope that helps

Cheers

Rob

Hello Mike.

We have a brilliant small shop here in Weymouth called eurofasteners, who stock all sorts of bolts, screws etc in metric, UNC,UNF, Whitworth etc in all sorts of variation of head and material.

If you can't find what you want locally, just let me know what you need and I'll post it to you.

Gone are the days of the local ironmongers unfortunately, where you could buy nails by the pound, in eco friendly paper bags!

Cheers

Rob

As a lot of peoples' first DSO's are of M42, for the obvious reasons, here's mine.....

This was my first go at producing a colour image using a mono camera and filters

Alt-az 10" LX200

DSI pro

Meade filters

No FR (didn't know they existed at the time!)

I learned a lot from putting together this shot.....

You need an IR blocker ....no, the glass in front of the chip isn't one, no matter what the manual seems to say

Find out what focal reducers are

Ditch the meade filters and get filters that are all IR blockers.

Rubbish isn't it

Focus sin't too bad though and....it was in colour....

I was pleased as punch at the time.....M42!!!!!

Cheers

Rob

Good idea Martyn.

Here's M82 from November 11th 2006, taken with a DSI Pro and 10" LX200 classic, alt az mounted...exposures about 15 seconds, I probably stacked 30 or 40 of them. It's not quite my first image as I tried M57 but never saved it, so this is my second.

Cheers

Rob