[RESOLVED] STXL 11002/FW8G settings in Maxim

Can anyone advise on the correct settings in Maxim DL v6 for the camera w/self guided FW? See below for an example of what I'm using and the results. The CCD image file is clearly not correct, but the autoguider image seems reasonable.

Thanks,

Bill

 

Thanks Doug. Made those changes. Guide image still looks black (in daylight). I notice the shutter opens/closes for the duration of the guider exposure when taking a guide exposure. That doesn't seem right. Any thoughts?

Bill

 

OK, so I tried it tonight. Focused the main sensor and then tried to focus the guider. I'm getting zero signal when using ambient light, however if I shine a light into the OTA the guider signal maxes out so it appears to be capturing photons. I moved the guider focus knob through its range but only see hot pixels. I've attached a screen shot of the settings. Any thoughts appreciated.
Thanks,
Bill

 

Have you checked the positioning of the pick-off?

 

Yes, I checked the positioning just before imaging and adjusted such that the "shadow" is just outside the FOV.

The more I think about it it seems that the guide sensor is in its proper place, active and detecting photons (at least when I operate in daylight or shine a light onto it). I wonder if for some reason there were just not any stars in the FOV, although it seems there should be something above zero detected by the sensor. It also seems strange that the main sensor shutter activates when taking a guide exposure (the pick-off mirror for the guide chip is in front of the shutter, correct?). Does this suggest something wrong in the settings?

Thanks for any thoughts.

Bill

 

Thanks Bill. Will any HDMI cable suffice or do I need a specific one?

 

Hi guys,

Well, I was able to get the autoguider working. As I suspected it was a question of having visible stars in focus. So- no hardware problem. But I'm still having the same issue with the main camera shutter activating during autoguider exposures. And now, when I take a main camera exposure, the autoguider exposure sequence stops for the duration of the main exposure. This must be a Maxim settings issue, but I can't seem to figure it out. Following screenshot shows the camera settings I'm using. Same for both cameras. Any comments welcome.

 

Thanks for the reply. No, I actually turned separate thread on to see if that resolved it, but did not so I reset to off.

 

From what you describe about the camera shutters making the click, click every time a guide exposure is taken, when you start imaging with the main sensor, you won't hear that shutter anymore. It's actually the guider shutter you are hearing. So, when you aren't exposing the main sensor, the guider shutter keeps cycling while taking guide exposures, but once you start a main sensor exposure, it stops and the shutter stays open. Are you sure that the guide chip isn't really taking exposures and guiding?

P.S. If I remember correctly, the STXL cameras were built the same way as the older STL cameras in that they had the guide sensor behind the main shutter so guide exposures had to be shuttered by the main shutter and that transferred over to the STX line of cameras also. So, while taking only guide exposures, the click, click you hear is the actual guide shutter on the filter wheel, but if you look down the scope at the main CCD, you'll also see the main shutter cycling also, until you start a main chip exposure.

 

Thanks for your response. I've now tried a simulation on the benchtop and found the same as described above in the field, as follows:

The imaging sensor and guide sensor both activate (i.e. both shutters open) when either a main image or guide image is separately requested (by Maxim DL, although was the same using CCDOPS) and whichever exposure was requested works. When both the imaging sensor and guide sensor are activated as in an image capture/guide sequence, the imaging sensor collects data but the guide sensor stops collecting data, although its shutter remains open, for the duration of the main sensor exposure (I could see this clearly in the field because the guide tracking graph stopped showing new data points). When the main sensor exposure ends, the guide sequence resumes but the result is no guiding during the main sensor exposure. As indicated I tried this simulation using CCDOPS with the same result so no longer believe it is a Maxim settings issue. The SBIG drivers are updated and all other connections/commands seem to work properly. Bill from SBIG suggested changing the HDMI cable connecting the remote head and main camera, which I have not tried yet. Any other thoughts welcome!

Bill

 

Thanks Bill. You are understanding the problem correctly. I agree that software makes sense (why I initially suspected Maxim settings), but using two different software apps I'm getting the same issue. Perhaps I should try reinstalling the drivers...

 

Let me try and describe the problem statement as I understand it: When operated independently, both sensors acquire and download images. This can be seen in the post above (from Nov 4) where both an autoguider image and primary sensor image are shown (both are the correct size for the respective sensors). The problem is that when operating together (as when taking a guided exposure), the guider sensor does not download data while the primary sensor is exposing even though both shutters are open. After the primary image completes, the autoguider download sequence resumes. I think for the images above the main sensor exposure was 60 sec and the autoguider exposure 3 sec.

The main symptom I observe is that whenever the main sensor or autoguider is set to image, separately or together, both shutters open. Since the autoguider sensor is in the FW in front of the main sensor/shutter, it does not seem right that the main shutter opens (exposing the main sensor) when only a guiding exposure is being taken nor that the guider shutter should open when taking only a main exposure. They open/close in synch with the main sensor having exposure priority if both are operating. By the way I was not able to fully reproduce the dual imaging problem in CCDOps (I've never used it for actual imaging) but the same shutter "symptom" was evident in my benchtop simulation.

Thanks again for your comments and ideas.