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pmrid
25-09-2022, 05:37 PM
I’m getting used to this device. I use it on an SCT and a newt. I’ve got the SCT organised alright because there is basically only the secondary mirror to adjust. But the newt is a bit less intuitive and the instructions are bleedin’ hopeless and the videos are often contradictory.

The sequence seems to me to be:
1. Load the software and start the camera.
2. Open camera properties and set the exposure, focus etc to your taste.
3. Identify the bottom of the focuser drawtube, open the green circle and activate the LeftRight and UpDown box.
4. Adjust the green circle to accurately match the size of the drawtube bottom for size and use the LR UpDown to accurately overlay it on the drawtube bottom.
5. Identify the reflection of the primary mirror. Open a red circle and adjust its size to match it.
6. Use the secondary mirror adjustment screws and overlay the red circle on it.
7. Open the blue circle and match and overlay it to cover the reflection of the OCAL device. Activate the crosshairs.
8. In the reflections, and using the focus and other camera adjustments, identify the reflection of the primary mirror center spot.
9. Using the primary mirror knobs, move the crosshairs to overlay the donut.

The result does not coincide with my laser tool. Perhaps it’s the problem. Not sure.

Does anyone use a different workflow?

mldee
25-09-2022, 10:16 PM
I've now got used to using the OCAL on the SCT, RC8 and Newt. I also have now used it on my new Sharpstar 150HNT, (which is an absolute delight compared to the C8 Hyperstar.)

With the newts, I still found that a well collimated laser, and even a Cheshire to check secondary squareness, were good steps before starting the OCAL, and then rinse and repeat after the OCAL. Eventually I always finished up with the OCAL cross hairs and the primary donut superimposed, Just took a lot of repetition.
Your workflow sounds OK, but the newts do get your head spinning with the number of adjustment variables though, including focusser tilt. I like the OCAL, but a good laser is still top of my toolbox.