Thank again. I wasn’t sure I understood the issue correctly. Not being a programmer has its downsides. Of course the upside is that no one can expect me to fix anything. 
I did this re-wire on Robofocus… Pretty straight-forward; or, as you said, you could make an additional cable. I posted the required changes in a different thread a few months ago.
To state the obvious for anyone who have might missed it (as initially happened to me), the direction is dependent on the side of the focuser that the motor is mounted. In a setup like Moonlight’s, the stepper is always on the same side, so no directional considerations. In Robofocus or similar where there are different mounting options, it becomes more important.
While not ideal, the path of least resistance, today, might be to mount the motor on the side that matches the software’s expected direction.
Craig
Just to follow up on this, the Rigel Systems folks adjusted their code so that my focus motor now runs in the proper direction. Just like SGP, Rigel Sys has always been very responsive to these kinds of requests. I would never survive AP if I had to code for myself.
Kevin
Hi Frank,
I ran into the same issue with Robofocus and SGP - the direction of autofocus being high to low numbers meant the focus curve was removing backlash on each step. The “curve” I get is not much repeatable and also not much of a curve. So I wanted SGP to focus in the preferred direction where the curve is generated with CCW movement of the focus knob on my C14 Edge. But the direction it was going (high to low numbers) meaning the knob was turning CW.
In Robofocus I had the following settings :
In = reducing value - CW movement
Out = increasing value - CCW movement
Backlash compensation = Out ; 150 steps
With the above settings that I have been using for years in Focusmax, I could not get SGP to get me the CCW movement on reducing numbers. Also swapping the settings in Robofocus software panel did not help.
I read up the Robofocus manual and there is a way to swap In/Out. What I needed was reducing focuser position should correspond to the CCW movement. I held the “Out” button the Robofocus unit and powered it on…after a few seconds the focuser was moving CW …and then I released the button.
Now, I see the following behavior.
In = reducing value - CCW movement
Out = increasing value - CW movement
I changed the Backlash compensation = In ; 150 steps
I think this should work but I need to test it out under the stars hopefully tonight.
Hi-
I’m aware of that robofocus trick and I did try it - but I don’t think it helps. It only changes the direction of the In and Out buttons - but it does not change the numeric values of the positions. So I believe SGP will still take the curve from high to low and it will be going the wrong way.
I could be wrong but I recall a moment of hope that did not pan out - so I had to change the wiring.
Frank
Hi Frank,
I will test it tonight but I am hopeful. I see the reducing focus position value are now corresponding to CCW rotation of the mirror knob. Previously that was “Out” and it was increasing focus positions. Will update what I get.
It will be very disappointing if it does not work. I did not realize this until my trial expiration and not being able to get too many clear nights to fully test everything. I now have purchased the license, but if this does not work (I dont want to do expensive/time consuming workarounds) I may be asking for a refund.
If your test does not work, why not simply reverse the wiring like Frank did. If you are unsure of the wiring, ask Frank.
SGP is incredibly awesome for such a low price. You won’t regret it. Ever since my first successful automation with SGP, I’ve had about eight consecutive successful and unsupervised automations since then.
Peter (aka “Peter in Reno” from CN)
Hi Peter and Korborh-
My robofocus is many years old - but the controller died last year and I got a replacement - and I think it may behave differently because it is a newer version. Even so I could have made a mistake - but I definitely remember getting the directions to reverse - but then realizing it had no effect on the numeric values. So I could have made a mistake or the contollers may be different - so I hope things do work for you.
Both the controller and sgp offer ways to change the meaning of In and Out - but my main suggestion is to let the user define focus compensation direction one way or the other - and then make sure autofocus happens in the right way - going up or down - to make sure backlash compensation isn’t invoked on each step. So I think sgp should just do the right thing during autofocus - and the user should only specify which direction gets no backlash.
Korborh I’m sorry if you didn’t get to test many things but one thing to try is plate solving with PlateSolve2 - which for me works very well and quickly. I had used Maxim with the built in version of pinpoint LE - and this is much better.
The autofocus does work well in sgp and I really prefer multi-star autofocus near the focus point - but it does take tweaking to get things set right - along with long backlash removal if focusing with the primary. The main thing I have trouble with is tiny specks that get counted as stars and throw off the focus curve - but if you can avoid that happening it works well.
Frank
Hi Frank, Peter,
I am happy to report that the Robofocus startup trick worked in reversing the movement so that SGP focus direction now (reducing counts) is moving the focus knob CCW. So far in my testing it seems to be working and producing a reasonable v-curve. I still need to play with it a bit more.
One issue I ran into was for some focus images, a large saturated star in the FOV was being detected (with bad HFR) and for some it was not. So it was throwing off the avg. HFR as there were not very many stars. I can appreciate the other concern of detecting too many false stars (hot px)…will be running into that one soon. Perhaps it would have been good for SGP to include some false HFR using some rejection.
On plate solve - just got that working and yes PlateSolve2 is really fast. Liking it so far.
Peter - I have my MaximDL/Focusmax setup working well but I wanted to move away from it for a couple of reasons. I feel FocusMax I have to try focus several times until I get something I am happy with. Automation is an attraction of SGP but then I will be moving to PHD2. I am willing to try some workarounds but re-wiring the hardware just for SGP (when Maxim/Fmax was fine) would be hard for me to justify. Fortunately I may not need to do that and hoping to get up and running automated…
Hi Korborh-
Well - glad it is working and I hope you get some more autofocus trials. Bright stars are a problem so some objects with bright stars in the center of the field will need special handling. I use cropping of about 40% to give more control over the field stars.
There should perhaps be both a min and max star size - in arc-seconds - to avoid outliers. I don’t consider these features to be “bells and whistles” because they are important to a key feature of imaging: focusing.
In my case I am not automated because I am using OAG with a cge-pro - and the solve/slew system for centering tends to leave an offset. For a high end mount like yours this shouldn’t be a problem - and you should be able to place guidestars on the OAG - I think.
When I reversed my robofocus and the numbering direction didn’t change - I wasn’t surprised because when you flip direction something has to give - if you have a min/max range set. If your range is 0-1000 and you are at 100 - then when you reverse direction - suddenly it thinks you can only go 100 in the ‘good’ way and 900 in the ‘bad’ way. Or - otherwise - when you flip the direction it suddenly says you are at 900 instead of 100. But I’m glad it works.
Frank
Hi Frank,
So even though the focusing direction and focus knob movement are as I want, I am still getting suboptimal results. I am still tuning the settings so the focus does not wander off and take too long. I am setting bin2 and 10sec for focus images with the nebula and star sliders half way (I guess that will depend on particular field). It does seem to work better than Focusmax when seeing is not that great. But with good seeing so far SGP is slower and not necesarrily better converged on focus - I have work to do. Hopefully SGP will add more features to get a robust whole image HFR.
Another issue is guiding. Since I am keeping my equipment same (moving from MaximDL), I am having to use PHD2. And there too I am getting worse results than Maxim - mainly in DEC. Have been playing with setting etc…but will need another good night to work on.
With both SGP and PHD2 - why do these programs not display RAW images (showing pixels) and instead some compressed blurred as you zoom in? I am used to seeing individual pixels with zoom and that view give much more information of the image.
So it is all not working as I need it to be. I will be working a few more nights to sort it out.
Korborh,
I am glad you got RoboFocus to work the way you wanted.
For PHD2, try to lower aggressiveness to about 60% for both axes. I thought you use Metaguide and it’s supported with PHD2.
Minimum Move is another important PHD2 parameter. The larger image scale for autoguider camera the larger Minimum Move in pixels for PHD2. Here are my settings for TEC 140 APO (980mm f/l) and SX Ultrastar autoguider for PHD2:
Image scale: 1.36"/pixel
Pixel size: 6.45uM
Search Region: 40 pixels
RA/Dec Aggressiveness: 60%
Minimum Move: 0.45 pixels
SGP dither: Extreme Dither
SGP Settle: < 1.0 pixel for 8 seconds
SGP Auto Guide: Pause auto guide during Auto Focus
PHD2 Noise Reduction: None
I hope the above settings will give you a good head start. Try to use my image scale and Minimum Move and calculate to match to your scope/autoguider setup.
Peter
I use 9 focus steps, binx2, exposures of 2 seconds with clear filter, with 40% cropping. The main time in focusing is in backlash removal - which involves about a full turn of the focus knob - and that takes perhaps 1-2 minutes to go out and back. I only sample a shallow part of the focus curve near focus - so it assumes the system is already near focus. This will not be as fast as FocusMax, but I find the accuracy to be about as good as possible - and it doesn’t take too long - and you have a sense of how good it is in the context of the focus curve.
I only use MetaGuide for guiding and I knew that Korborh used MG only for collimation. phd2 is better integrated with SGP but I have never used it - and MG does work well with SGP dithering. But other aspects of automation with MG are less implemented. My imaging is mostly manual because I don’t have the accuracy to place the guidestar on the sensor with OAG using SGP’s sync/slew centering method. In short - I can’t speak for how well phd guides compared to maxim. With a high end mount I didn’t think the guiding software could have a strong impact on the guide quality.
I agree that the smoothing/interpolation behavior on zoom-in is undesirable. I have used such features in windows graphics and it is built into the graphics API for displaying images - and it can be turned on or off. I agree it should be an option because some people like everything to be smoothed - but at least two of us don’t.
Frank
One thing that surprised me about autofocus is that I believe the “reject nebulosity” value is stored with the target sequence - or something. So it isn’t global and if you pull up and old sequence it will switch to the value you used with that target.
So that is something to be aware of.
Frank
Thanks you Frank and Peter.
Not being able to see and zoom in as RAW pixel level images is irritating. I am having to save the images and open them in Maxim as I want to pixel peep. I don’t think I am going to get used to it…will just continue using another application to view. I hope SGP and guiding programs show RAW images.
Peter, like Frank mentioned, I use Metaguide for perfecting collimation on my two SCT’s but have not used it to guide. I have a setup that worked with 1sec exposures since the AP1200 mount is very easy on guiding.
I read through the PHD2 help and I will need to experiment a bit to get the guiding results I am used to with Maxim. I don’t know what specific hysteresis or other assumptions Maxim uses, but it has been working well for me. I am hopeful PHD2 will do good. My only concern is if there are any inaccuracies in the centroid calculation itself when integrating 1sec exposures.
So focusing is the main one in SGP I need to get working optimally. Thanks to the suggestions here I have a good chance of success.
Actually I use sgp in concert with other things like maxim. SGP is mainly meant as an acquisition software and not so much on the processing and analysis side - except things to monitor the subexposure quality as images arrive. For people like you and me who already have an older version of maxim, the two work well together. I use many tools for analysis - and sgp recently made the acquired images available for direct loading in ‘watch file’ mode in a certain directory.
So I don’t think it’s bad to use maxim along with sgp - especially if you already have it. I prefer sgp for acquisition and like its autofocus, and support for dithering with guiding apps. But that’s just my preference. And sgp is improving over time.
Frank