Apply ROI

[Jonathan Shields]

First just to say the Colour Noise reduction feature works very well. In 8 second exposures of M101 in the current "never gets dark" UK conditions it was a noticeable improvement over Bilateral Filter.

I noticed the Apply ROI button which seems to restart the live stack with the selected value applied. I can see why that would be necessary but the diagram of the ROI seems to imply you can move the ROI with the pan and tilt buttons...is that correct ?

[admin]

Hi,

yes, the results of colour noise reduction can be very impressive, particularly in the early stages of a stack when there are not may frames so far. Later on as the number of frames builds up and the noise level generally drops, the effect tends to be smaller.

As you noticed changing the ROI to a different size will reset live stacking - in theory I suppose it would be possible to avoid that, but it would add a good deal of complexity to the live stacking code for an ability that would rarely (if ever) be intentionally used.

You can move the existing ROI (if you are already at a size less than the full camera size) by draging the darker grey box in the ROI selection control (or by clicking on that control and using the keyboard arrow keys).

Using the 'Select ROI' and then 'Apply ROI' buttons lets you select a new, smaller, custom ROI by drawing the required area on screen using the red selection rectangle before pressing 'Apply ROI'. This process will always change the size of the ROI, so will reset live stacking. Once you have completed this process, you can move the new ROI around using the dragging or keyboard (or pan/tilt control values) as mentioned above.

hope this helps,

Robin

[MikeT]

Robin,
I'm experimenting with the select/apply ROI as a work method for an earlier feature request for planetary imaging automatic ROI selection (I think that was in the feature request forum).

So far so good... I manually select a small ROI around Venus and apply it.
This gives some random sized small ROI
I centre the planet in this ROI using the Feature Tracking tool
Then I switch the ROI to one of my standard sizes (240x240)
This stops Feature Tracking guiding so I have to remember to turn that back on.

But overall this is a good improvement and saves quite a bit of faffing around trying to get the planet in the centre of a small ROI

Thanks,
Mike

[admin]

Hi Mike,

glad that it is proving useful. I will add that I am not sure how using a 'flip' setting in the camera controls will interact with Select/Apply ROI. Probably best avoiding that combination!

cheers,

Robin

[Jonathan Shields]

Hi,

yes, the results of colour noise reduction can be very impressive, particularly in the early stages of a stack when there are not may frames so far. Later on as the number of frames builds up and the noise level generally drops, the effect tends to be smaller.

As you noticed changing the ROI to a different size will reset live stacking - in theory I suppose it would be possible to avoid that, but it would add a good deal of complexity to the live stacking code for an ability that would rarely (if ever) be intentionally used.

You can move the existing ROI (if you are already at a size less than the full camera size) by draging the darker grey box in the ROI selection control (or by clicking on that control and using the keyboard arrow keys).

Using the 'Select ROI' and then 'Apply ROI' buttons lets you select a new, smaller, custom ROI by drawing the required area on screen using the red selection rectangle before pressing 'Apply ROI'. This process will always change the size of the ROI, so will reset live stacking. Once you have completed this process, you can move the new ROI around using the dragging or keyboard (or pan/tilt control values) as mentioned above.

hope this helps,

Robin

Thanks for your reply. All in all the new version has some decent features. Clearing the stack when the ROI is changed seems pretty reasonable to me just logically as stacking images at different resolutions surely wouldn't work. The ability to drag the ROI as you describe sounds potentially quite useful as I generally use it with small planetary nebulae etc and its quite tough to get such things right in the middle with an alt-az goto dob. I'll try it at the next clear night.

I also saw Tiago Ferriera using the new push-to assistant on his channel and I will look forward to trying that in my next session as it seems likely I can then do push-to without Stellarium and the ASCOM telescope simulator. Stellarium on Windows is pretty crash prone for me so that's a good thing.