EAF Pro attachment for EDGEHD8 needs some thought

Scott Horton

Hey team,
I just received the updated bracket for the EDGEHD8 and EAF Pro. The coupler is way too long. At native focal length with the celestron TPiece, ZWO EFW and ZWO CAA, the EFW will NOT clear the charge and temp probe cables when the image train is rotated.
I dont mind unplugging the EAF since this was the advantage of the Pro model, but now I cannot use the temp probe.
Please design a shorter coupler so we can move the bracket inward.
An alternative software fix would be to allow user defined CAA 180° rotation limits.
Thanks!

Tech@ZWO

Scott Horton What software are you useing now?ASIAir and NINA support rotation limits.What does it refer to “a shorter coupler”? Additionally, could I take a look at how your equipment is set up and have you take some photos? You can mark the parts you mentioned in the photos.

Scott Horton

Tech@ZWO. Setup: EDGEHD8 native focal length. Image train in order from OTA: celestron T adapter -->CAA-->7x36 EFW-->2600mm pro. I have an EAF pro installed. As you can see in the photo (photo 1) - when the CAA rotates the image train - the EFW just clears the EAF; however, it has to be unplugged or it will run into the power and temp probe cables. It's fine to unplug the power on the Pro model, but now I cannot use the temp probe cable.

The "coupler" is your connection from the EAF Pro to the focus knob on the HD8 - see photo 2. If the coupler was shorter, I could move your adjustable bracket forward and give more clearance.

Software - ASIAIR, the most recent beta, I believe 2.4.4. Yes, 180° CAA is supported, but it's not user defined. It just picks 180° based on where the camera is sitting for the first frame. There should be user defined limits of rotation to toggle to prevent the CAA rotating one direction or another or the real fix would be a shorter coupler.

Thanks!

Tech@ZWO

Isn't the EAF (Electronic Auto Focuser) connection for mounting your focuser on the side? That's why there's an obstruction. The standard installation is the one shown in the picture. You can try making a shorter connector, and we will also record your request and feed it back to our team to improve the software's custom rotation range settings.Alternatively, manually add gaskets to the CAA to change its initial zero position and see if this works.

Scullbone

Tech@ZWO nope, it connects off the back with a C8.

Scott Horton

Tech@ZWO What!!?? No offense, but thats a ridiculous answer especially from a ZWO tech... these are your products. You should know this is the bracket you sell to install the EAF to the back of an SCT... SMH. Also, how could I possibly add spacers there and not affect backfocus. This is wild.
Ok, please consider user defined limits for the 180° rotation of the CAA and or a shorter coupler for the EDGEHD series SCT couplers you make for the EAF.
Thanks!

Scullbone

Here’s what I used to solve the clearance issue I think you’re describing. https://mwdastronomy.com/wp/product/edge-hd-eaf-clutch-kit/

Scott Horton

Scullbone Thank you!

Tech@ZWO

Scott Horton This is mainly caused by the design of the mounting position of your telescope's focuser. Currently, the official side does not provide a better solution. The spacer does not need to be too thick, and it is not used to increase distance—instead, it is for adjusting the initial zero position of the CAA. You can adjust it gradually, and it will not have a significant impact on your back focus. If the method of adding a spacer does not work, no other solutions can be provided temporarily, or you may limit the rotation to 90 degrees.

Scott Horton

@Tech@ZWO and anyone with similar issues.
I used a #30 bit, drilled pilot holes just a few mm above the flexible portion of the coupler, used a 4mm fluted thread tap, re-threaded then chopped off 18.5mm of coupler. The bracket now slots in on the 3rd slot from the inside and gives way more clearance and works like a charm. Will follow up with some photos. Hopefully ZWO can start producing shorter couplers to fit their accessories. I can now use my CAA and EFW without worring about it running into the EAF, or my EFW and OAG combo.

Scullbone

Scott Horton Photos would be great! I haven't noticed any bloat in my star sizes, but the solution I posted has resulted in more outliers in my focus run. I have a hunch that it introduced some backlash. Be good to go back to a direct drive to eliminate variables.

Farhadharati

there are a few shorter coupling in the EAF bracket set that are made for other scopes that can be modified to solve ZWO CAA clearance issue with celestron edgeHD 8", I just upsized the shorter coupling hole ( on the telescope focuer side) to 1/2" usinga drill, and now this problem is solved, I also ordered a few thin spacer to add between the CAA and telescope so the CAA sit upright. here is m image train: Edge HD8, 0.7 reducer, SCT/M48 adapter, 12mm spacer, ZWO CAA with M48 adaper,18.8mm spacer, SVBON new OAG, ZWO 36mm EFW, 42/42 2mm male to male adapter, ASI294MM PRO,
I am going to reduce my spacers by 2mm or perfect back focus,
I replaced the original Celestron OAG with the new SVBON OAG that has a wider prism and way less backfocus( only 16.4mm).