iOptron IEQ45TM instruction manual Set Anti-backlash, Meridian Treatment

5.4.3. Set Anti-backlash

All mechanical gears have a certain amount of backlash or play between the gears. This play is evident by how long it takes for a star to move in the eyepiece when the hand control arrow buttons are pressed (especially when changing directions). The Go2Nova anti-backlash feature allows user to compensate for backlash by inputting a value which quickly rewinds the motors just enough to eliminate the play between gears.

To set the anti-backlash value, scroll down and select “Set Anti-backlash”

Set Up Time and Site

Set Display and Beep

Set Anti-backlash

Meridian Treatment

Set Eyepiece Light

Heating Controller

Upgrade R.A. and DEC

Firmware Information

Press ENTER. A R.A. anti-backlash screen will display:

R.A. anti-backlash:

0000 steps

One step equals to 0.09 arc second.

To adjust steps move the cursor to each digit and use the number keys to input number directly. Press ENTER – “DEC anti-backlash” will display:

DEC anti-backlash:

0000 steps

One step equals to 0.10 arc second.

Move the cursor to each digit and use the number keys to set the anti-backlash. Press ENTER to go back the previous screen. Press BACK button to go back to main menu.

While viewing an object in the eyepiece, observe the responsiveness of each of the four arrow buttons. Note which directions you see a pause in the star movement after the button has been pressed. Working one axis at a time, adjust the backlash settings high enough to cause immediate movement without resulting in a pronounced jump when pressing or releasing the button. The hand controller will remember these values and use them each time it is turned on until they are changed.

The 8407 hand controller has a function to test the mount backlash number and can store the anti- backlash steps here. The maximum steps are 9999.

5.4.4. Meridian Treatment

This function tells mount what to do when it tracks across the meridian. There are three options. Stop Tracking will stop the mount when it passes the meridian. Telescope Flip will flip the telescope and continuous to track the object. The third option is Continue to Track. In this case, the mount will keep tracking and the OTA could hit the tripod leg if the mount is not monitored.

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