23 February 2016 The Moon - a quick way to do a mosaic

[Bizibilder]

Taken last night as the Moon approached my neighbours tree so I had to be quick!  The trick was to take 2000 frame panes along the terminator (3 panes) and the other 6 panes of 1000 frames each.  Each processed in AS2 with 100 frames stacked.  This trick ensures a decent image of the terminator and halves the "data collection time" for the rest of the mosaic.

[gnomus]

Very nice.  Your moon has a better exposure than my effort.  Can I ask how you set up your imaging camera?  (I set my exposure time so that the top of the histogram 'dances' around the 200 mark.  It did not get up near 255 once.  Yet when I look at my image it seems that odd bits (crater rims and so on) are a bit burnt out.

 

[Rodd]

Nice--I have always wanted to do a mosaic--but did not really know how.  Will Registack splice them together, or do you need another software like Pixinsight or Phooshop?  Does resolution increase or decrease with a mosaic?

 

Nice job

[laudropb]

Very nice mosaic image.

[Bizibilder]

Gnomus - To use the histogram with your camera you should set the exposure to about 65% of "full scale".  In your language the histogram "dances" around between maybe 140-180 - never let it get so the histogram touches 100% (or 255) as this means at least part of your image is saturated or "burnt out" to pure white and you cannot retrieve the data.

The trick when doing this is to first find the brightest part of the lunar disc - use the mount controls to move around the disc until the histogram "maxes" - and then set the exposure to give about 65% full scale.  Do not change the exposure at all whilst you take all your panes - some areas will be "dark" and the histogram may only reach 40% or so - don't worry, it will be correct when you combine all the panes.

Another way to "overcook" crater rims is to over-sharpen with the wavelets.  Less can be more!  I now use Lucy-Richardson deconvolution (freeware ImPPG - http://greatattractor.github.io/imppg/   ) as I find it much better overall.  Wavelets can be a real pain to get right.

 

Rodd - to combine the panes use something like Microsoft ICE (Image Composite Editor) (or Image Compost Editor when it doesn't work!! ).  Just open all the panes in "ICE" and hit the button - it works 95% of the time.  Failure is usually due to insufficient overlap of the panes.  You can sometimes get round this by making "mini-mosaics" of a few panes and then putting them back into ICE and combining them to get the full mosaic.  Always make sure that you have cropped any "rough edges" from all your panes or the combining software will throw a fit as it can't tell a rough edge from a mountain range!  I also use Photoshop Photomerge but if you don't have that software it doesn't help you much!

 

[Rodd]

1 hour ago, Bizibilder said:

Gnomus - To use the histogram with your camera you should set the exposure to about 65% of "full scale".  In your language the histogram "dances" around between maybe 140-180 - never let it get so the histogram touches 100% (or 255) as this means at least part of your image is saturated or "burnt out" to pure white and you cannot retrieve the data.

The trick when doing this is to first find the brightest part of the lunar disc - use the mount controls to move around the disc until the histogram "maxes" - and then set the exposure to give about 65% full scale.  Do not change the exposure at all whilst you take all your panes - some areas will be "dark" and the histogram may only reach 40% or so - don't worry, it will be correct when you combine all the panes.

Another way to "overcook" crater rims is to over-sharpen with the wavelets.  Less can be more!  I now use Lucy-Richardson deconvolution (freeware ImPPG - http://greatattractor.github.io/imppg/   ) as I find it much better overall.  Wavelets can be a real pain to get right.

 

Rodd - to combine the panes use something like Microsoft ICE (Image Composite Editor) (or Image Compost Editor when it doesn't work!! ).  Just open all the panes in "ICE" and hit the button - it works 95% of the time.  Failure is usually due to insufficient overlap of the panes.  You can sometimes get round this by making "mini-mosaics" of a few panes and then putting them back into ICE and combining them to get the full mosaic.  Always make sure that you have cropped any "rough edges" from all your panes or the combining software will throw a fit as it can't tell a rough edge from a mountain range!  I also use Photoshop Photomerge but if you don't have that software it doesn't help you much!

 

Thanks--I have Pixinsight and of course registack.  My sensor (Skyris 274) is actually quite large.  Should only take about 15 frames fro the whole moon with a C11 edge at f10--I would like to do f20 though!

[Leveye]

Man does that look awesome full size! Well done and inspiring work. Thank you for sharing.