What is a EQ mount

[daniel-lloydw]

So still looking for my first mount. and i hear EQ3-2 is the best for my scope. shame about the price

but what is a EQ mount and I hear people saying setting on up to polarise.

what do the do and what are the benefits compared to other mounts, what the diffrence when people say EQ1 or EQ2..... Also can you by the mount on its own and attach it to a slandered tripod or do they come as one?

[Cornelius Varley]

This link http://www.themcdonalds.net/richard/index.php?title=A_Quick_Tour_of_an_EQ_Mount should give you everything you need to know about equatorial mounts and their operation.. The EQ1, EQ2 etc refers to the model number of the Skywatcher range of EQ mounts, the bigger the number the greater the load capacity of the mount (other manufacturers use other numbers and may not match). Mounts usually are supplied with a tripod and don't fit camera tripods.

Peter

[Capricorn]

EQ is short for Equtorial, and why I have no idea.

You align the things with the earths axis and nothing to do with the Equator. Someone will come up with the answer to that.

The idea is that you match the axis of rotation of the EQ mount with the axis of rotation of the Earth.

Then, if you attach a simple drive motor that rotates at the same rate as the earth - once in 24 hours, the scope attached to the EQ mount can be pointed at something big ang bright and then the big bright thing stays in the field of view of the scope.

The problem we have is that we tend to think in X-Y-Z co-ordinates and movement.

Left/Right/Up/Down/Foreward/Backward refered to as Cartesian Co-ordinates.

I say problem as nature doesn't use this system, everything is in Polar co-ordinates and mechanics.

The EQ mount simply uses this Polar system as well.

An EQ mount needs just one motor to track an object, but 2 are better simply to redirect the scope.

Also watch a constellation when it rises. Say Orion - the first bit is the star Heka (top left), thsi will be heading upweards, then the rest appear. By the end of the evening Orion is setting however Heka is now heading downwards. The constellation has rotated.

If you use an Alt/Az mount (X-Y-Z movement) the scope does not rotate the same - it doesn't rotate at all.

So for astrophotography an Alt/Az mount will eventually show this lack of scope rotation and the image is blurred. An equitorial mount does however rotate the scope so Orion (any other) and the scope are matched, simply no blur.

No overly difficult to set up, an EQ mount will have a scale on the side, first set the angle to whatever your latitude is. The aim the axis at Polaris by looking through the polar scope. It is a little more detailed but that is the basis. For simple visual alignment that will probably do as things will drift out but not too fast and you will move around objects when viewing so the target gets reset. You use Polaris as it is easy to locate, relatively separated and lies close to the axis of the earths rotation. Wait around a few thousand years and it will not be so convenient.

You say an EQ3 is best for your scope, will disagree a bit as the more solid the mount is then the better it is for any scope. An EQ3 may be adaquate but an EQ5 will be better, and an HEQ5 better still, then comes the EQ6 and Skywatcher have an EQ8 somewhere. Suspect for an EQ8 you will need a fork lift truck licence.

[mister brot]

hello daniel-lloydw...I wrote a short book (sorry)on your other post "hello from wales"and I posted links on astronomy basics telscopes and how to set up and align an eq mount....maybe you missed it......anyway here is link for setting up eq mount

.the what is a eq mount starts at about 4 min. 30 if you want to skip over the beginning. and as I said in your other post if you know nothing about astronomy or telescopes try watching these..I myself have a hard time reding instruction and understanding them so I try to find videos on the same subject.........sorry this is getting long again good luck with your search for that mount ...

robert

[themos]

It's called equatorial because it enables things to rotate while staying on a plane that is parallel to the Earth's Equator plane.

[brantuk]

I have a fork lift license so if you do get the EQ8 (and a forklift truck) I'll hapilly come over and drive it for you lol

[brantuk]

To be a bit more useful - when you set an EQ mounted scope to point at the pole star you will only have to track stars in a single plane (RA or right ascension). That is - you'd only have to turn a single axis knob. If it's motorised then the object will stay in the eyepiece without having to touch the scope. This is very useful for both observing and imaging.

An Alt/Az mount conversly needs to be pushed up/down and left/right constantly to track. A motorised alt/az mount can keep the object in the eypiece sufficient for observing - but imaging this way will be very limited due to star trailing which is inevitable when tracking in both planes and not polar aligned.

[ollypenrice]

Think of of it this way; if you are at the north pole Polaris is directly above your head and the sky turns around it. Stars never rise and never set, they just go round in a circle. Now go half way to the equator and look at the sky. You are at a tilt of 45 degrees with respect to how you were at the north pole so now Polaris is not above your head but the stars still go round it as they did before. So now they rise and set.

An equatorial mount simply allows you to tilt it at 45 degrees so that it cancels out the tilt that you introduced when you moved down to latitude 45. In effect it behaves as a normal alt azimuth (right left/up and down) mount would behave at the north pole. If yu are at latitude 38 or whatever, you tilt the EQ mount to your latitude to recreate the north pole situation.

Olly

[Matt Scunthorpe]

That is very well said Olly. That has explained the EQ to me as well, always helps to have a little understanding of how these things work instead of just using them

[Woking]

It also depends on what you want to do too. Imaging, GOTO, and motorised tracking are usually done with an EQ mount, but if you want to go down the visual manual route AZ or Dobsonian are best for their simplicity and ease to use.

The EQ3-2 is a well made mount but watch your scope weight though. I used to have a 4" frac on one and the vibrations and their dampening time were just ridiculous for anything in high magniifcation. By the time the wobble stopped from moving either axis or focus tweak, the object had usually travelled halfway through the EP view.