Mosaic tile edges

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Mosaic tile edges

Postby Kingsley » Wed Mar 16, 2016 4:09 am

Hi,
Is there any way to suppress the square tile edges when mosaicking? I thought maybe it was a weighting issue but can't seem to figure it out
I'm just re-manufacturing the old 1992 HI cube

Thanks for your help.
K
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Re: Mosaic tile edges

Postby ste616 » Wed Mar 16, 2016 9:12 am

Hi Kingsley,

Can you please provide us an example of what you mean by "square tile edges"? I am afraid I don't know what you're referring to.
cheers
Jamie Stevens
ATCA Senior System Scientist
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Re: Mosaic tile edges

Postby Mark.Wieringa » Wed Mar 16, 2016 9:44 am

Hi,

Not sure I understand exactly what you are referring too. Maybe you can show a picture?
If you are seeing square tile edges in the middle of your mosaic you probably need to increase your image size - it means the primary beam response hasn't gone down far enough yet at the edge of the individual images.
Square edges at the outer boundary of the mosaic are normal.

Cheers,

Mark
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Re: Mosaic tile edges

Postby Kingsley » Wed Mar 16, 2016 9:53 pm

Thanks, It could be that Mark, It's in the middle, and looks like a jigsaw puzzle type thing.. I've attached a bit of the image as I don't think I'm doing a great describing job!
Attachments
edges.png
edges.png (5.11 KiB) Viewed 3376 times
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Re: Mosaic tile edges

Postby Kingsley » Thu Mar 17, 2016 2:59 am

Aha! changing the image size does indeed appear to have fixed it! would there be an ideal value, I put it at 4,4, beam just to quickly see what it did
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Re: Mosaic tile edges

Postby Mark.Wieringa » Thu Mar 17, 2016 8:40 am

Hi,

normally imsize=2,2,beam would be sufficient, but if your mosaic is sparse (below Nyquist sampling) you may need to increase this a bit.

Cheers,

Mark
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