Observatory grade mounts recomendations

Striker (Tony) · #1 12-12-2006, 08:10 PM

Hi Guys,

Still awaiting a response from Insurance company but I need to consider what mounts are available.

I am looking at the following mounts and recomendations and why.
Even order of preference would be great.

I have not consider the OTA's and at this stage is not important.
Paramount is out of the question.

1) Losmandy Titan
2) Astro Physics AP900
3) NJP Temma II
4) EM 400 - Temma II

Striker (Tony) · #2 12-12-2006, 08:13 PM

heheh I voted AP900....lol

Go for the AP Tony

iceman (Mike) · #3 12-12-2006, 08:40 PM

Pros and Cons of each?
Cost of each? (or is that not in the equation)

g__day (Matthew) · #4 12-12-2006, 08:42 PM

The AP have long waiting lists - around a year isn't it? The EM 400 has great carrying capacity and terrific tracking and goto accuracy in all its review I see.

h0ughy (David) · #5 12-12-2006, 08:43 PM

go the titan

Striker (Tony) · #6 12-12-2006, 08:51 PM

Cost is not a factor with these Mike as there fairly close with the NJP being the cheapest.

Just opinion is all I ask..you can reply with Pro and cons as your opinion.

Lee · #7 12-12-2006, 09:05 PM

I didn't vote, I don't know squat about any of them.....
I do hope the sod who pinched your G-11 dropped it on his big toe though!

Omaroo (Chris Malikoff) · #8 12-12-2006, 09:23 PM

I'd love to see a cross-section, cut-away shot through the Titan. It looks so geometrically simple that I reckon it must be possible to build one given time. Needle-roller bearings are no problem and neither are the shafts. High-grade Duralamin round stock is difficult to get in that sort of size though. Worm drives are commercially available, if a bit expensive for good 7" ones or larger.

Hmmm.... interesting...... time to get the lathes out?

jase (Jason) · #9 12-12-2006, 09:54 PM

Tony,
You know my views on this (PM).

Additional things to consider are;

Don't believe the marketing hype around PE peak to peak statistics. Ask owners as to what they experience.
Despite what everyone thinks, PEC is still very important. A mount with a well-calibrated PEC can minimise the amount of auto-guider corrections resulting in rounder, sharper stars. You only have to see the PEMpro statistics to realise the importance of PEC.
Check the Takahashi mounts, PEC support does not exist. AP and Gemini do.
Check how many star alignment points are supported in the mounts in-built pointing model. The more the better, but don't stress about it as you'll eventually want to purchase MaxPoint or T-Point.
Capacity on most mounts is under rated. The Takahashi mounts can generally take more load than specified, as can the AP and Titan but you need to verify balance.
Support - never under estimate it. There is probably a larger Gemini user base than AP and Takahashi combined consider the same code is used on the GM-8, HGM-200 and Titan. ...and of course the world renowned G-11 that made astrophotography a possibility for the average Joe.
Balance, balance, balance... Some mounts are more critical in the balance of the OTA/counter weight than others. The Titan is a little touchy with this and requires reasonable balancing, though when operating in 18v mode the servos have some serious grunt (torque) so motor stalls are rare.
The Titan 50 sounds really cool, but don’t expect major improvements. The “50” modifies the gear ratios to provide more torque. Note: tracking accuracy remains the same as the original Titan.
Make sure backlash particularly in DEC is minimal if not non-existent. Some play maybe required depending on manufacturer specifications. Most mount firmware has backlash compensation build in, but this needs tuning to work well.
Taking about tuning, no matter what mount you get from top to low end. They all require tweaking to maximise performance. Some may require re-greasing worms or optimising worm block spacing, through to simply software settings for auto-guider aggression.

If you want to know any details on the Titan, I'm happy to share my experience.

jase (Jason) · #10 12-12-2006, 09:59 PM

You may also wish to reference this site for some additional Titan info:
http://www.nightskyphotography.com/titan_tips/

Enjoy

Omaroo (Chris Malikoff) · #11 12-12-2006, 10:02 PM

Quote:

Originally Posted by jase

You may also wish to reference this site for some additional Titan info:
http://www.nightskyphotography.com/titan_tips/

Enjoy

How good are those disassemly photos.... thanks Jase.

Dennis · #12 12-12-2006, 10:03 PM

Hi Tony

I have a Tak EM200 Temma2 and consider it to be very backwards in terms of electronics and software capability compared to my 10 year old Vixen GPDX with the Skysensor 2000.

To implement GoTo on the EM200 Temma2 requires either a computer or a PDA, as there is no native GoTo hand controller as in the SS2K for the GPDX and other systems such as Gemini, Meade and Celestron hand control units. Actually I have read about a Tak GoTo controller but it is very expensive and very few people consider it seriously.

The Tak doco is very poor and finding information on Tak accessories is quite difficult. The Vixen hand controller is very rich in functionality e.g. comet tracking, satellite tracking, multiple user locations, etc whereas the Tak EM200 Temma 2 has none of this, just a hand paddle. The EM200 does not have PEC either, so is this important to you? A lot of the functionality in the Tak EM200 Temma2 is activated by pressing and holding hardware buttons, whereas the Vixen Skysensor 2000 has all this implemented in the software/hand controller. For example:

To make the EM200 operate in the S Hemisphere, you have to press and hold a button S1 when powering on the mount.
If you forget to flip a switch from H to N, the auto guider calibration takes off at slew speeds and not guide speeds.

Mechanically the EM200 is a beautiful mount, but it is woefully behind in terms of electronics and software. I’m not sure if my comments on the EM200 apply to the NJP, EM400, etc.

Cheers

Dennis

PS - Are you saying your mount went as well? I figured it was just the small bits not bolted down???? Don’t answer if it’s too painful or not appropriate in this thread.

Striker (Tony) · #13 12-12-2006, 10:12 PM

To answer your question Dennis...everything went.

So the light box is on hold..Hope you understand.

They didn't take the small bits they took what was bolted down.

Thanks guys....I know there all nice mounts but they do have differences.

33South (Chris) · #14 13-12-2006, 08:48 AM

Tony, have you considered a Parallax mount - I dont mean the HD300C

Striker (Tony) · #15 13-12-2006, 12:38 PM

I have never heard of these Chris...I have had the high quality parrallax rings but never new they built mounts.

Dont know if there is any retailers in Aus but I would prefer to stick with the more well known and used mounts mentioned above.

33South (Chris) · #16 13-12-2006, 12:57 PM

Quote:

Originally Posted by Striker

Dont know if there is any retailers in Aus but I would prefer to stick with the more well known and used mounts mentioned above.

I agree, but they do have the 'mmm black and heavy' appeal

For reference

http://www.parallaxinstruments.com/mount.htm

Havent seen them locally but scroll to the bottom US$25,000, loading 300lbs weight 250lbs + counterweight shaft 45lbs.

jase (Jason) · #17 15-12-2006, 02:22 PM

Well, well Tony, its come to this... You've asked the audience (below is their response)...

Losmandy Titan = 46.15%
AP 900 = 30.77%
NJP -Temma II = 7.69%
EM 400 - Temma II = 15.38%

What would you like to do now: Phone a friend or 50/50?

Striker (Tony) · #18 15-12-2006, 02:59 PM

Yep my decision has been made.

AP900 has been ordered..should get it Feb-March next year.
Already payed the 50% deposit.

I couldn't resist the oportunity to get such a nice mount even though the Titan would have been a easier option for me knowing Gemini.

I got this oportunity of a friend who was on the AP notification list for 2 years.

Now I have to consider OTA options but NO rush.

I personaly condsider the AP mounts 2nd top of my list behind paramount ME well well well well on top as no1.

jase (Jason) · #19 15-12-2006, 03:07 PM

...So you phoned a friend.

Great to hear Tony.

AP say they'll star shipping 900GTOs in Feb, as you indicated. Have you got the mount plate design so you can ready your pier?

Striker (Tony) · #20 15-12-2006, 03:38 PM

Yep ordered the Pier plate and the pier plate flat base adapter.

Should be able to fit it easy seeing the father in law is a stainless steel boiler maker....he can alter my pier to suit these plates.

Next I will be working on some top notch security for the observatory, I do have some time before all this will come together.

You have been a help to Jase...thanks mate.