Check the Real-Time number of the HFR Stars

Hello everyone, I am a new user of SGP I can not figure out if there is a function to check the focus (manual operation) to make me see real-time dynamically HFR (number of graphics) of the stars, as present in all of the CCD software.

I’m not sure if this is what you are looking for, but right click on the image and choose “calculate HFR”.

1 Like


If you are looking for real time feedback on the lowest HFR seen while focusing manually, simply turn on image history. We need to better document this…

When you do so, each frame will show large print of HFR in the upper left corner and the image history graph will show trends and also records the lowest HFR seen.

1 Like

Would that work when using a dslr live view or would you need to loop exposures?

You need to loop exposures

Thanks Ken, I tried and it is correct what you told me.
For those not lucky enough to have an automatic focuser, perhaps it would be better (you could implement in future versions?) that the HFR calculation was done only on a star choice by clicking on it with the mouse, would give more speed to the calculation and give the user the star’s choice to control, exactly as you do in Artemis software on Atik cameras.

Best Regards, STRA


You can select a sub-frame for a single star if this is what you want to do (and/or choose fast download if your ccd permits it) in the Frame and Focus module.

I’m not sure whether Image History will then display only the HFR of the sub-frame (I use a stepper motor to automate focus) - but it may well be worth trying. The manual is very helpful if you haven’t already looked through (see extract below); apologies if you have :=).

I can recommend automating focus with an ascom compliant absolute stepper motor as a very efficient and effective way of focusing.


Thanks Barry, I’ll definitely try the next evening.

Previously when ‘looping’ exposures for a manual focus run the HFR analysis for the entire image would fresh continuously
giving you a single HFR average for the image. That stopped working some time back and turning on image history has not restored that functionality. They are not the same thing.

You have to turn the the analysis off and back on again to force it refresh for the current image which is tedious
I used to be able to just let it run while adjusting focus and getting continuous real-time feedback.

I also use auto-focus which works very well as long as the starting value is good.
I used to be able to run a a quick check on each filter to make sure each one was in the ‘zone’, otherwise it can pick up and old value and is so far out that auto-focus fails and you find out when you have to toss out all the subs on that filter for the run.

It used to work perfectly and I really REALLY look forward to the simple bug getting fixed.

1 Like


No idea how to reproduce the issue you describe. Please see here:

Sorry if my grasp of the English language failed me.
I did mention this previously and was it was confirmed by one other as an issue.

Good News. As of Sequence Generator Pro Beta it’s working again and Image History is back in control.
I jumped on Image History as the cause in earlier betas but to no avail so thanks for that.

Tempting as it is prepare and submit logs for every ‘Sequence Generator is not working’ or centering error I receive I usually read the manual and check the forum to see if there are relevant active issues before wasting your time. I can see you are very very busy so first I will go back to the last Non-Beta Version and see how that goes as a reference point, as I really don’t have enough clear nights to waste, before deciding if I will be able to make any further ‘contributions’