RE: [APML] What's the Best Way to "Combine" Two ImagesofDifferingTimes?

["Carlos Milovic F." <cmilovic@yahoo.es>]

>>Then we can measure the standard deviation (rms) in the images and
use the inverse-squares
>>of the rms as the weights.
>What program can handle inverse-squares. Do you have a snapshot?
>I'm a little slow in visualizing where/what values need to be
>entered.

Hi Wade

 

PixInsight, throught the PixelMath process, has included the power operator, wich allows you to perform a square... Anyway, you don't need this feature. What you have to do is the following:

 

- Make a preview of a "pure" background area in every image, or in the object of mayor interest (a small section).

- With the Statistics tool calculare the standard deviation of the samples.

- Now copy this value in a paper and calculate the square. Inverse the result (1/x).

- In the PixelMath process, use those calculated values as the weighting factor for the propper channels/images.

- It is a good idea to check the Rescale box just in case the values go out of range. Remember that the 32bits acuraccy is distributed in the normalizated range as floating point numbers, not integers.

 

 

Good luck!

 

 

Regards,

Carlos Milovic F.
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