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Alt-Az or Equatorial?

Gary70

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Gary70

Gary70

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I have a 5" refractor on its way, it is OTA so unlike my 1st scope which I sold it has no mount; That was on an equatorial mount which was ok, but I am considering getting a simple Alt-AZ mount,

As you would expect from a long refractor I would be using it for planetary / moon and so on, and I have no interest in AP. Is an alt az mount as simple and elegant to use as i imagine or should I just jump back into CG4/5 territory?

I have seen the Vixen star guy for import from the states (if any one knows where in the UK let me know). i dont have 100's to spend so sub £400 is my limit.

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Marki

Marki

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Nice Gary. Look forward to your first light once the scope has arrived! I used mine on an EQ5 (manual) fitted with a pillar extention. I really thought about getting a skytee II for alt-az simplicity though. The pillar will really help though - saves kneeling down whenever you want to observe anything at the zenith, and prevents the scope tube knocking the tripod legs too - I'd really recommend you get someting like that whatever mount you go for.

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John

John

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I'm a firm fan of alt-azimuth mounts, the simpler the better. I use a Giro-style one on a 16" pillar extension and a CG5 tripod for my ED120 refractor - gets the eyepiece up to a really decent height even when viewing the zenith :smiley:

I can track comfortably at 240x with the above set up and a little practice.

Telescope House sell a Giro on a tripod for just over £300:

http://www.telescopehouse.com/acatalog/Bresser_Giro_Mount___Tripod.html

An alternative would be the Skywatcher Skytee II.

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Mike73

Mike73

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I've got a 4" f/11 Lyra and currently have two mounts a motorised EQ5 and a Alt/Azi SkyTee 2 mount, one of them has to go to fund the other....

I havent long had the SkyTee, its first real test was a couple nights ago on Jupiter. I'm used to nudging a dob so I thought it would be fairly simple to nudge a SkyTee but as I'm using a long refractor I found myself pushing the focus tube so which made me wonder if I was slightly putting it slightly out of focus with each movement?

Using the slow motion controls was a little tricky as its quite a long frac and probably not something I would want to do all night.

But the SkyTee's advantages were in its quick set up and portability which is a big plus.

The EQ5 just takes more time with polar alignment and balance which isn't too big a deal for visual but considering I'm used to dobs tracking is awesome!!

One thing I did notice was that my views of Jupiter were far better with the Alt/Azi than the EQ5, this 'may' of been down to seeing conditions but with the SkyTee I positioned Jupiter on one side and let it drift across the FoV so there was no movement or vibration like the EQ5 as it tracks?

At the moment I'm completely torn between the two..!? :confused:

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Qualia

Qualia

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I've got two mounts (each with a different tripod), the AZ 4 and the Celstron CG-5 which is essentially a decent EQ5. I'm happy with both.

The CG-5 mount is supported by a 2" stainless steel tripod, the AZ 4 by a 1.75" stainless steel tripod. I find the quality and sturdiness of the former a lot better.

There's a metal holed-tray on both set ups to keep your EPs in when observing and whether you raise the legs to standing height or lower them for sitting, you'll find that both tripods establish a firm foundation.

I've had no problems with either of the tripod's plastic feet. The CG-5's feet are of heavy duty, thick, solid plastic whilst the AZ 4's are softer, more pointed and not so heavy duty.

The CG-5 mount has a provision for visual polar alignment (you take off a cap built into the mount and actually look through the mount to polar align) and used manually, with no Go To or tracking motors, I have found the RA and Dec knobs to be smooth and precise. Sometimes these plastic knobs wobble a little loose, but if that is the case, you just squeeze them back into their slot as you did when you first set up the gear from its package.

The AZ 4 is a different game. You point and aim and the ‘tracking’ is done all by your own hand – lifting and pushing, pulling and tugging - if you get my meaning? With the 4.5kg 4" f/10, with a 9 x 50 viewfinder and EP, it works absolutely fine. Nevertheless, I think one needs a little practice getting the balance and tension just right to one's own 'strength of tug' disposition, that is, when moving the two axis (horizontal and vertical), so that the planets don't leap out of view too often. With that said, I generally find myself tracking by pushing on the tube itself. I have found that there is wobble in the image if I knock the tripod or OTA but this calms down in a matter of seconds. The ease of set up with the AZ 4 is mastered in no time and as to its weight, well, it makes an excellent 'grab-and-go'. I have my scope set up permantly on the AZ 4 in my study and literally pick the whole thing up and carry it onto the roof to view the Sun every morning and Moon every evening with ease.

Back to the CG 5. So long as you don’t dismount the mount from the tripod, you can set up the CG 5 in minutes. Mine is set up permantly in the city, but if I'm going away I carry it in a long bag, slip it out, put on the counter weight, level the tripod and of you go. If you dismount the mount I can imagine it will take longer to set up, but not that much longer seeing as you’re only screwing in a longish shaft through the tripod into the mount which is pretty much the same for the AZ 4.

As suggested the stability and tracking of the CG 5 far surpasses that of the AZ 4. Indeed, I can measure doubles, sketch and track planets, Lunar craters, and Solar spots with this mount to quite a significant degree of magnitude - within seconds of arc - which would be impossible with the AZ 4 and its longer settle-down time if the OTA is knocked a little. My CG-5 came with a 5kg counter balance weight and with the whole set up (OTA, Telrad, Viewfinder 9 x 50, EPs etc) I have seen no reason for concern. There is literally not a hint of wobble.

To my eyes, both the AZ 4 and the CG-5 reveal - in their fashion - a consistently high level of finish quality; the silver casting and black paint is clean on both, the axis run smoothly with no stutter, there's a real feel of craftmanship and quality on both mounts and tripods. Where the AZ4 trumps is in its ease of use, set up, not being placed in weird positions when tracking objects at the zenith and its weight. On the other hand, the CG-5 trumps in terms of smooth and consistent tracking, and no issue of settledown time from vibration or image wooble.

Aesthetically speaking, both set ups look stunning with the frac.

I hope this helps.

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AndyH

AndyH

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A couple more links to add to the excellent suggestions above.

Various flavours of the Giro mount. This is the link to the actual mount manufacturer............

http://www.tele-optic-tecnica.de/mounts.html

I had a swiss made, W.O. badged EZ touch mount. Quite superb and smooth. No need for slo=mo's. Expensive, but better internal quality than the later W.O. chinese sourced copy. They ARE expensive now though :( Price list can be found up on top left of this link.............

http://www.aokswiss.ch/index_mont.html

The above two links show some super alt/az mounts. They DO require a tripod or pillar though.

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Gary70

Gary70

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All good advice guys thanks,

And as I hoped no one has swing my opinion away from an alt-az set up, Simple set up is perfect.

I will get it in wood, aesthetics I feel are improved with wooden tripods, just my opinion mind.

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John

John

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Wood has an improved vibration dampening effect, so I've read. Very impressed with my Tal tripod so I guess those reports are correct. Looks nice too ;)

I used to have a wonderful ash wood tripod from Tele Optik. This one:

http://www.tele-optic-tecnica.de/tripods.html

It extended to around 2 m in height and was rock solid even with a 6" refractor on an HEQ5 on board.

Another item in the "why did I ever sell that ?" category I'm afraid though :sad:

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glowjet

glowjet

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If you ever fancied adapting an industrial tripod for Astro use, there is possibly nothing better than the old wooden highway surveyors theodolite tripod, I picked an ex Gov. one up for £10 at a Boot Sale some years back, beautifully made with bronze fittings, and they can still be found quite reasonably priced, they are the same pattern as the ones produced nowadays from Teli-Optik, Berlebach etc. those sell with a hefty price tag though :)

John.

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