Observatório Astrográfico do Boqueirão avatar
Hello fellows,

I'm in need of help. Today I discovered that ZWO realese an update that can push the EAF focuser from the default maximum steps 65000 up to 600000 steps. That sounds great since I had that problem / situation with my SCT regarding the limit of 65000 steps, as many users do. 
So, I made the firmware update on my EAF's with the latest provided by ZWO (FW 3.3.8) and then I updated the Ascom Driver to the latest version (V. 6.5.19).
Everything went smothly but when I open the EAF on my program for image acquisition, problems started (which the previous driver I never had this problem).

I use the Astrophotography Tools V. 4.30 and I love it. When I do shift+clic on focuser to select the brand and Ascom driver, he turned on and I put the data refering to the steps, like you see in the image:



After this he's apparently working, don't give me any error, but the problem is when I open the settings (red rectangle) to open the ASCOM driver things are this way:



I can't controll him through the ASCOM properly as I use to do with the previous driver (which the privious driver doesn't allow me to go up to the 600000 steps) and the only way I can make it properly function is if I do shift+click in focuser as in the first image that I've posted here or through those settings (which they are very roughly to work with and susceptible to errors - Red box in the image bellow):



Can anyone help me with that? I've tried to remove and install everything grom sratch, nothing worked.. Only if I go with the older version of ASCOM that doesn't allow me to go with the steps above 65000, which is a problem for me when using the SCT telescope.
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AstroDarkSky avatar
I don't have a set up where I can reproduce the problem unfortunately, but the last ZWO driver update before .19 completely broke my guide camera where it wouldn't download any images until reverting to .17 so I can't rule a driver bug out based on that bad experience.

However, you mentioned the firmware update…. have you set the zero position again? I had weird problems when I ran a ZWO firmware update and after setting the zero point again, everything was back to normal.
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Observatório Astrográfico do Boqueirão avatar
Thank you for your input.. Yes, I set the zero point again. It was one of the first things to make the physical focuser to work properly. But the problem persists..
You don't actually have the 0.17 driver around that you can send?
AstroDarkSky avatar
Looks like I cleaned up old versions so I don't have it anymore . It 'used' to be available by clicking on "Other ver x.86" on the driver page under the main download button, but now it points to... .19 which is the same as the download. There are comments/complaints about ZWO not listing their changelogs accurately and requests for older driver versions on the blog site for this reason. It is a bit hidden, but maybe somebody there has a lead:ZWO user forum

That's how I found out about how widespread the last driver problem was.
Observatório Astrográfico do Boqueirão avatar
I've solved the problem. Like you said.. This is a bug from the driver. The latest driver allows the EAF to go above the standard 65000 steps but the interface freezes and doesn't allow to use the commands properly. So what I did was I too the two dll files from C:\Program Files (x86)\Common Files\ASCOM\Focuser\ZWO_EAF named: "EAF_focuser_ASCOM" and "EAF_focuser_ASCOM_x64" out of the folder and kept them in the desktop.. then I remove the ASCOM driver completly. I had in my backup the old driver setup and install all over again. Then I went to the same folder and substitute the two dll files and voilá. Everything is back together fully working and I can go up to the 600000 steps.

If anyone have this kind of problem and don't want to wait for ZWO to solve this issue, just contact me and I gladly pass a copy of the files and explain more in detail the process. Thank you very much @AstroDarkSky for trying to give all the help you can get and bring me light that push me to try this. Here's the proof of work.

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