confused

[Fumangord]

Hello guys and girls;

I am looking to buy a new scope for sky watching and some photography. My question is which would be the better buy a Reflector or a Maksutov-cassegrain? budget is not limitless so maybe only looking to go to about 130mm aperture. Not too bothered about massive magnification as detail would be what I am after.

Regrds

Gordon

[LukeSkywatcher]

Hi Gordon

I cant comment on Maks because i've never used one.

However

The SkyWatcher Explorer 130P (reflector) seems to be a very very popular scope for a first scope and is highly regarded by a great number of people.

Of course for imaging you would need it to be on an EQ (equatorial) mount rather then an Alt-Az mount.

I have a SW Heritage 130P (same optics as the Explorer 130P) and can vouch for its quality.

I'm NO expert but i am as happy as Larry (whoever Larry is) with the 130P.

[Fumangord]

hi Lukeskywalker

I have been looking at the skywatcher 130P also the 130M which has the motor drive which for imaging would be a must I would think. Can you explain the differences between the alt-az and eq mount plz, not quite up to speed on that side of it.

Ta!

Gordon

[tms48]

Im just a begginer but as I understand it the alt az is logical, left right and up and down but it is not related to the movement of the stars. The eq is different it follows the axis of the earth, so as the stars appear to spin around polaris it tracks that path and keeps the relevant object in view.

[Ant]

Hi,

An ALT/AZ mount moves up and down. The stars however move in an arc.

The equatorial mount replicates the arc to enable accurate tracking.

Are you interested in the moon/planets or deep sky objects? As this makes quite a difference in the choice of scope...

Cheers

Ant

[LukeSkywatcher]

An Alt-Az mount is a manual up/down/left/right mount. Think of a Dob and you are on the mark. An EQ mount allows you to track stars,planets etc in RA (Right Ascension).....basically the movement of celestial objects across the sky as they appear to go east to west.

The EQ mount will allow you to track objects and keep them centred in your view which makes imaging much easier. Imaging with an Alt-Az mount is much much more difficult but not entirely impossible if some of the images i have seen on here attest to.

The "M" on the SkyWatcher you are looking at means that the mount is motorized. So it has some sort of Go-To system or a dual/single axis motor (im really not too sure). The "P" in the specs means that the primary mirror is parabolic in shape. Parabolic mirrors are favoured by most because they deliver a brighter/sharper image.

There is (im sure) a version of the SW 130 which is both "P" & "M". I'm not 100% sure but i think that version comes on an Alt-Az mount.

I'm sure someone with more understanding will be along very soon to correct any errors i have made. But essentially for imaging you really should be looking at a scope on an EQ mount.

[LukeSkywatcher]

Hi,

An ALT/AZ mount moves up and down. The stars however move in an arc.

The equatorial mount replicates the arc to enable accurate tracking.

Are you interested in the moon/planets or deep sky objects? As this makes quite a difference in the choice of scope...

Cheers

Ant

Ant & tms have just summed up the difference between Alt-Az and EQ

PERFECTLY.

They make more sense then i do.

[Fumangord]

Thanks ppl,

ok a few issues cleared up there for sure, however, the Skymax 127 supertrack comes on an alt-az mount and according to the blurb tracks celestial objects no problem would I be right in thinking that this mount would have two motors where the Eq would only require one?

Gordon.

[tms48]

I dont think that supertack and goto mount are different they appear to be both alt az, it seems to be just in the software and hand controller. The supertack still has to slew and rise and fall but it just follows a single object that is chosen. The goto needs to be set up so it knows where it is and then can find requested objects. I think this is correct perhaps someone can confirm this. If a motor is fitted to to an eq mount then it only tracks in one direction as it naturally follows the path of the stars, and would not need to be computer controlled.

[LukeSkywatcher]

This is where i start reading and learning. I know what Go-To is but have no idea about SuperTrack.

One finds and tracks while the other just tracks?

[Ant]

It is possible to track in ALT/AZ, but as you've suggested you need two motors. With an EQ mount (in theory) you need only one.

For planetary imaging an ALT/AZ mount will be OK - it's only for long exposure imaging for DSO's this becomes an issue (field rotation).

Cheers

Ant

[LukeSkywatcher]

It is possible to track in ALT/AZ, but as you've suggested you need two motors. With an EQ mount (in theory) you need only one.

Ah thanks Ant that explains the difference.

I have a 90EQ scope and know that i would really only need a RA motor drive for it. I wouldnt really need the DEC axis motor.