Building & Using a Tracking Mount for Astrophotography
Using the Tracking Mount
Before using the mount, it is important that its drive rate be set so that the large gear (with its attached nut) rotates once per minute. This can be easily accomplished by putting a small permanent mark on one tooth of the large gear as well as a small index mark on the bottom plate next to the gear. One simply adjusts the supply voltage until it takes a minute for the gear to make one revolution. Additional accuracy can be achieved by timing for a longer period, say 5 minutes. Be aware that the power supply output voltage (and tracking rate) can vary as battery voltage drops as well as with temperature changes. So it might be best to check the drive rate before each photo session.
Also note that after about a cumulative hour of tracking, it is necessary to reset the mount as follows:
- Lift the upper plate, disengaging the gears.
- Spin the large gear and its nut until it snugs up against the upper plate.
- Lower the plate and re-engage the gears. This will enable another hour or so for tracking.
If care has been taken in constructing the mount according to the dimensions in Gary Seronik's plan, with careful polar alignment, and careful adjustment of the motor speed, this mount can easily provide tracking for some nice astrophotos. I have found that ISO 800 or 1600 with a 2 minute exposure gives nice results. Some of these results are on the next page.
Dec 28, 2014
Oct 4, 2011
Oct 4, 2011
Jul 7, 2015
- Fujifilm X-T223.6%
- Nikon D50025.4%
- Nikon AF-S 105mm F1.4E8.2%
- Olympus M.Zuiko 12-100mm F47.5%
- Panasonic Lumix DMC-G857.2%
- Sigma 85mm F1.4 Art6.7%
- Sigma 50-100mm F1.8 Art5.1%
- Sony a63006.4%
- Sony Cyber-shot RX10 III3.7%
- Sony Cyber-shot RX100 V6.3%
|Kingfisher by cjf2|
from An A to Z of Subjects- Week 11, K
|Bull Rider Being Launched by RBFresno|
from FX bodies and very high ISO