Local field focus feature

Having done some troubleshooting recently on some imaging trains I thought it would be interesting if Voyager could have an option in local field focus to ignore portions of the field (i.e focus on the outer portion of the frame and corners only, ignore the center x% entirely). While not a super important feature it may help some people with less than well corrected scopes obtain a reasonably good field overall. This would of course sacrifice field quality in the center but could be a useful trade-off for some.

Bill

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Hi Bill

The LocalField is very sophisticated autofocus (not sure all have understand this) and divides the selected sensor part into areas to which logic give weight according to the star shape, the deteriorated ones are removed directly. The central part of the image has its own dedicated area which by definition has a much lower weight than the other areas also because it usually contains non-stellar objects.

Instead, you can reduce the computation area as a percentage of the image center if you want to exclude non-flattened area use Central Region here:
https://wiki.starkeeper.it/index.php/AutoFocus_Setup#LocalField_Mode_Tab

You can refine the displacement of focus plane using Focus Final Offset +/- Steps here:
https://wiki.starkeeper.it/index.php/AutoFocus_Setup#Focuser_Tab

All the best
Leonardo

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Interesting to see you post that Leonardo. I did not realise that LocalField excluded distorted stars and weighted the selected areas effectively by quality, and significantly de-weights the center of field.

I normally use Robostar in any case but it is interesting to see the sophistication of Localfield. I used that when I was imaging with an SCT and it was notable that unlike my previous imaging software it did not go off chasing bright nebulosity in the centre of field, calling it a star.

This was very informative Leo. Thanks! :sunglasses:

+1… thank you Leo, I learned something new about Voyager tonight !