Tilt issues return!

[symmetal]

Did you not make the test jig Stefan? 🤔

If you post a full size sub it would be easier to assess what the actual tilt effects are. From your test image the stars look OK but it's too small really to tell.

Even if there was tilt elsewhere in the system reversing the orientation of the shim would have made a difference if it was actually working. It's possible your threaded pieces are too well meshed, and not allowing enough free movement to react to the shim face, and are just locking down on the thickest part of the shim, and not introducing any 'wanted' tilt at that point. I imagine you only want a few mm of thread meshing where the shims are introduced to enable some free movement to occur.

Alan

[04Stefan07]

On 14/09/2022 at 06:41, symmetal said:

Did you not make the test jig Stefan? 🤔

If you post a full size sub it would be easier to assess what the actual tilt effects are. From your test image the stars look OK but it's too small really to tell.

Even if there was tilt elsewhere in the system reversing the orientation of the shim would have made a difference if it was actually working. It's possible your threaded pieces are too well meshed, and not allowing enough free movement to react to the shim face, and are just locking down on the thickest part of the shim, and not introducing any 'wanted' tilt at that point. I imagine you only want a few mm of thread meshing where the shims are introduced to enable some free movement to occur.

Alan

Oh, I completely for about that! I did buy the parts for it too.

Have attached the sub.

frame_and_focus_1.fit

[symmetal]

Your latest image is actually very good and many people would be happy with it. 🙂 Here's the CCDI analysis. Your min and max FWHM figures are much better compared to your previous postings.

Pixel peeping, the top left is visually the worst showing slight triangular stars which I've found with my WO scopes means that corner FF spacing is a bit too much. Stars on the left are a bit larger than those on the right so slightly out of focus down the left. The tilt looks like it's purely left to right.

Fixing tilt like this requires very small adjustments and the tilt jig is really the only way to improve this. As you have the bits you may as well build it. 😊 Using the tilt shims, it depends a lot on how tightly the parts are screwed together so is hard to reproduce reliably. On the jig you should be able to fit your Zwo tilt adjuster with a spacer between it and the filter wheel to allow allen key access, followed by the camera, such that you have the correct 55mm FF backspacing when it's fitted back on the FF. You'll then appreciate the tiny adjustments needed on the tilt adjuster which you would never manage trying it in the field. If you need to use the shims instead you can easily see the effect of rotating them and how tight they need to be screwed together.  

Alan

[04Stefan07]

Thanks, Alan.

I've got a long weekend coming up so I can spend some time building the rig. Luckily my 3D printer will come in handy.

I'll report back with my findings.

I've got my RC6 with my 1200D I need to setup as well!