The HEQ5 Project
Part 3 - In the Field
Project pages
The HEQ5 Project (Part 1)
The mount arrives (Part 2)
Setup in the field (Part 3) 		Updates and fixes (Part 4)
The Price (Part 5)
Finished Project (Part 6)
Howto and information pages

Setup in the field

Setup out in the field went very smoothly. There is (as mentioned above) no level built into the mount so I took a carpenter's level with me. Leveling went smoothly and I used my orienteering compass to get the mount roughly north/south. When the mount was on the tripod and I started tightening the spreader bar a leg shifted. There is no place to put a level on top of the tripod when the mount is in place so I had to try to use the bottom of the tripod head to re-level. There isn't much flat space here and I prayed that the bottom of the casting was accurate.

Once the thing was together fitting the C8 OTA was fairly simple; balancing it wasn't as simple as it should have been due to the tightness of the mount. Eventually everything came together and I could start to figure out where and how to run all of my heater cables (sigh).

I'd say that setup took 10 minutes and teardown a bit longer (it was dark). There were no major glitches encountered.
    Setup sequence that works

    1. Open the tripod legs
    2. Screw the center post DOWN INTO the tripod head then tighten the spreader
    3. Use a compass to put the azimuth pin north
    4. Level east-west with a combination level
    5. Level north with the combination level
    6. Loosen the spreader and free the center post from the tripod head
    7. Place the head on the tripod and tighten the center post (loosen the azimuth screws a bit first)
    8. Tighten the spreader
    9. Place the mount with the counterweight bar level
    10. Engage all the clamps
    11. Place the counterweights on the shaft
    12. Place the scope in the dovetail clamp
    13. Balance RA (always balance the RA axis first)
    14. Balance Dec
    15. Adjust polar scope for date/time
    16. Connect all heaters and power
    17. Wait for Polaris, have a coffee, let the optics come to ambient temperature
When polar aligning the mount, take care NOT to place a lot of stress on the altitude adjusting screws. One needs to be loosened before the other is tightened and don't use a lot of muscle. They CAN be bent which could ruin your whole day. The same goes for the azimuth adjusting screws. Loosen one before tightening the other. These are much smaller than the altitude screws so be even more careful. You just need them snug. Also, loosen the centre post slightly before adjusting the azimuth. This will let you put a lot less muscle into the job and save your screws.

For instructions on readying and using your polar alignment scope follow this link.

Here's the HEQ5 with the C8 mounted at home and at the dark-site ready for business

  


Note the nice 'flat' on the sides of the mount. The motors and electronics live in here but it's perfect for some Velcro tabs as a place to put my heater control/power box. And that's where the unit now lives.

First Light

The first time I had the HEQ5 out at the dark site it impressed me.

I arrived at the dark site with half an hour to go before sunset. Following MOST of the instructions from the HEQ5 sheet, I got the polar scope aligned with the RA axis in five minutes. Another two minutes got the two 'zeros' for the alignment scope setup and I was ready to go. A bit of a warning here... the instructions are wrong so here are some that work. Once Polaris put in an appearance it took 15 seconds to polar align the scope.

How well did it align? I put Jupiter in the center of the 9mm EP field of view (226x) and walked away. Fifteen minutes later Jupiter was still in the center of the 9mm FOV. So, not too bad... good enough for piggy-back and visual work.

As for stability, the thing was pretty darned good. In the swirly little winds that night the fork mount would have been twitching like crazy yet the HEQ5 stayed solidly planted. Damping times were in the 2 second range after giving the OTA a good rap. In the past just touching the focusing knob (even my modified one ) would have set the scope jiggling. Not anymore, now all I see is mirror shift =). Even though stable I felt it COULD use a lower leg brace so one was constructed.

Next time out

Another night at the dark site, this time to do some actual observing and work my way through some more Messier objects. The scope now has the home-brewed lower leg brace installed and it makes a huge difference. The last time I was out I had 2 second damping times when I tapped the OTA; now it just twitches once and stops. This modification obviously works.

Star-hopping with the HEQ5 was a joy. Objects at the zenith and towards the north are now available to me without incurring chiropractor's fees and having dual-axis drives makes moving from star to star in the finder a snap.

There have been complaints in the past (mostly about the EQ6 but they use the same motors/transmissions) that the Synta mounts vibrate. This may be due to the fact that they haven't built any micro-stepping into the motor control firmware. The motors just run at their 1.8degree/step (I think) rate. I used the HEQ5 on Saturn at 226x and noticed no vibration. The Rajiva MCU Update adds 32 micro-steps to the tracking and should fix this.

Ya just gotta read the manual
This refers to the mount AFTER the Rajiva/Conrad upgrade
At the last starparty I went to, the HEQ5 setup in just over 5 minutes. Several times I noticed that the mount was drifting off target fairly rapidly and seemingly randomly (much to my consternation). Then I noticed the red LED was lit on the hand controller (it's on by default) that showed that periodic error correction was in use. Now I hadn't trained the mount, so I turned off PEC and it tracked like a champ. When I got home I downloaded the PEC table from the mount and had a look at it... what a mess. When I was writing my software I did some PEC stuff and loaded a HORRIBLE table into the mount. Well, 30 seconds with a text editor fixed that and now the default PEC table just says 'track sidereal' which is quite fine until I do some PEC training.

The mount is a keeper! Stable, simple to setup and tear down, simple to align and simple to use. That's about all I wanted.

On to part 4 - Updates and fixes
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