Native SGP interface to SmartLock?



Any thought been given to offering a priced drop-in using Innovation Foresight’s SmartLock focusing technology for ONAG users? I realize that: (A) There are few ONAG users and (B) Gaston (rightly so) charges a licensing fee but it sure would be nice to have.

SGP and FocusLock Connection

I have been looking at SmartLock myself for use with my SX AO-LF OAG.


Yes, we talked extensively with them at NEAF and will almost certainly add support for the SmartLock in some capacity.

We’re trying to figure out what integration with the SmartLock looks like. Gaston’s software already does the focusing and integrates with PHD for guiding. So I believe SGP would just need to adjust focus per filter and start/stop the SmartLock focusing at key times (meridian flips, slews, maybe during image integration?)

But yes, it’s most certainly in our crosshairs and fairly near the top on the “things to do” list.



That is good news.

I’ve been testing the trial version of Optec’s FocusLock, which seems to work, but will not interface with my SBIG filter wheel so I have to handle filter offsets manually. If you need access to an ONAG, or an alpha tester for new code, let me know, I’m just down the road in the Drifwood/Wimberley area.


Good news for ONAG users, but how many are there out there and using SGP, probably can be counted on 2 hands I guess … I really would love to see this technology available to OAG … but then one needs to be 100% sure oag and main are identical in focus point.
I could think of other items much higher in the priority list.



Agreed! I also have considered the SmartLock system and would love to see support in SGP!


Is what is needed is a standard interface to a guider?

I can think of a few things:
void StartGuiding();
void StopGuiding();
GuideStateEnum GuideState { get;}




SmartLock is a focusing system - not guiding. It looks at the shape of the image from the guide camera and does continuous focusing so interfacing with SGP might involve coordinating focusing to happen between exposures.


I’m an ONAG user. Very happy with it. I AF with SGP "in the normal way."
I haven’t used Focuslock though.
I don’t understand why one wants to have SGP communicate with Focuslock in any way.
Should not AF just be disabled in SGP if you’re using Focuslock?


As I understand it, FocusLock is a continuous focuser which means it may be changing focus during an exposure. If you have a focuser that does not vibrate, that might be ok. Otherwise, an interface to SGP is needed to coordinate focusing to be between exposures.


All true. If we gain access to the API we can do some pretty cool stuff though:

  • Lock focuser movement during exposure
  • There are 3 zones for focus, green, yellow, red where red is bad.
  • Only allow for focus between frames
  • If during a frame, focus moves to “red”, stop the frame, refocus and then restart it.

While you are probably right… sometimes we just do stuff for no other reason than because we think it’s cool.


It will absolutely work with an oag. They have a device called the Lacerta which creates a similar diffraction pattern and that can be monitored by FocusLock in the exact same manner. This is how I plan on using it. I believe it threads into any guider that can take 1.25" filters but I believe their target is the lodestar.



I just wanted to add my name to the list of peole using the ONAG and the focuslock software. I’m using it in real-time with my Edge 800, FR, moving the primary mirror. I’ve done careful analysis of subs with and without the focus movements and have not been able to detect adverse impacts on star HFR. Th focuslock movements are very small. No more pauses for autofocus routines! The down side is that Focuslock does not inteface with SGP for filter offsets. While my Astrodon fliters are supposed to be parfocal they are not perfect. Hopefully SGP and focuslock can talk to each other in the future.
Thanks for the great software! Tim


I actually need to talk with the SmartLock folks about how this piece specifically works. How do you handle filter offsets manually since the guider doesn’t go through the filters I would think this may present a problem for offsets?



Jared has a valid point, you’re probably not going to be able to do direct real time focusing when filters are in use. I think we will have to manually characterize any filter offsets, store those in the SGP Equipment Profile, and have an SGP routine that talks to SharpLock (I think FocusLock is the name of the Optec software, SharpLock is IF’s technology) which in turn can drive the focuser in real time.

I’ve tried FocusLock but it has no SBIG native support, only ASCOM (SBIG’s fault, not Optec’s) so I can’t read the filter positions to apply offsets.

And, I may be all wet :>).

BTW, for the first time since becoming an SGP user, the latest autofocus routines work with my RC scope. I’m getting very nice V curves. Thanks!

Driftwood, TX


Jared, the answer is that I currently do not do my offsets. I’ve set it up so that Lum is always spot on. The B, G, and Ha channels suffer (R is parfocal). Given that I’m doing LHaRGB combinations and collecting the color data Binned 2x2, I can tolerate slighlty worse color data for now. I’d just like to get it better in the future. Best. Tim


To state an obvious point, the need for filter offsets depends on whether the filters are in front of both the main and guide camera or just the main camera.


Given the way the ONAG is set up and the way it works best filter offsets are almost always required if the filters are not parfocal. Check out the documentation.
To be sure some might choose to put the filters ahead of the ONAG but they would likely lose a lot of signal for the guide camera. Best–Tim


Sorry I missed the source of confusion. Hopefully I can clarify (sometimes I fail).

  1. When you set up the ONAG you make the guider parfocal to the camera/ filterwheel combination. Usually using the Lum filter.
  2. Focuslock uses the guidecamera image to determine what side of focus you are on. Note the the ONAG is using the same field of view as the imaging camera, it is just using the IR portion of the spectrum.
  3. Focuslock moves the focuser to achieve focus of the guidestar and because this is parfocal with the imager it is also focusing the light for the imager simutaneously.

Ths works well for the filter for which you established parfocal"ness" but not other filters that are not parfocal.

  1. To deal with offsets Focuslock can be set up to change what it considers “focus” to be for the guidestar. Because the system knows which direction it is out of focus it knows exactly what it’s offset is from focus (either inside or outside).

  2. You can set the filter offsets on Focuslock by focusing your camera with the filter in question and then tell Focuslock that this position is the focus point for the filter in question.

This only works if there is someway to tell Focuslock what fliter is currently in use bu the camera. Right now the system works fine “dumb” because I am taking a hit on my focus points for the filters that are not parfoal with my Lum filter.

Hopefully this helps…it may not…best. Tim