Robert, welcome aboard!
Your timing problem with the StackShot rail sounds like its "Tpulse" setting has gotten changed to some value around 10-12 seconds. To correct this, press the Config button for a moment, then in the Global Config menu, press the Select button until Tpulse is selected (has the ">" character in front of it), then press or press-and-hold the Down button until the value is around 500 ms.
The reason I think your problem is Tpulse is that you say "
StackShot light stays on 10-12 seconds". As far as I know, the duration of that light is controlled entirely by Tpulse.
You also say that "
Luckily StackShot knows to wait until the exposure is over before the next shot", but actually it doesn't. The StackShot just runs "open loop" with no feedback from the camera to the controller. If the camera is slow, the controller just runs on ahead while the camera gets behind. That's another reason why I think the StackShot is running slow, not the camera.
I notice that you're using mirror lockup.
Does that require two shutter pulses per frame, or with the 70D can you keep the mirror locked up forever and just cycle the shutter with one pulse per frame?
If it's the former, requiring two shutter pulses per frame, then you might also be having extended times per frame because the StackShot controller box will make your total time per frame be Tsettle + Tpulse + Toff + Tpulse + Toff, as shown in Figure 4 on page 9 of the StackShot manual that you can download from
https://www.cognisys-inc.com/downloads/ ... al_1_4.pdf . This use of a single Toff parameter for two conceptually different purposes -- time for mirror lockup versus time for actual exposure -- is one of the few design deficiencies in the StackShot controller. It can be overcome by using the StackShot controller panel built into Zerene Stacker, which provides two separate parameters for those functions ("Time between shutter pulses" and "Time after last shutter pulse").
Zerene...strips my EXIF data. Any way to prevent this? Or add EXIF back to the final image?
At this time, there's no way to prevent it. The simplest way to add EXIF back to the final image is to use some photo editing program such as PhotoShop. The procedure goes like this: Open the Zerene Stacker final image and any one of the source images. Use select_all/copy/paste to move all the pixel values from the ZS image into the source image. Then flatten and save the resulting image to a new file. The result will be the pixel content of the ZS final image, merged with the EXIF settings from the source image.
I hope this helps!
Best regards,
--Rik
Sorry 
