Processing Drizzled Integration Images - Fullframe DSLR

[fulatoro]

I am using a Fullframe Camera and using DrizzleInteggration. I end up with LARGE images that take considerable amounts memory and CPU to process.

Here is my question.  Should I rescale the image before doing any processing?
Or alternatively, rescale, process a smaller scale image until I am satisfied with the workflow then reapply to original image?

Advice?

Moussa

[pfile]

maybe it makes sense to use super-pixel debayering and then drizzle? the full-sized files from the camera are interpolated anyway, so maybe the drizzling would be a better way to recover the full-frame image than the interpolation that takes place during debayering. super-pixel debayering does not do any interpolation at all, so the RGB files are 1/2 the height and 1/2 the width of the sensor.

rob

[gvanhau]

Hello
 For DSLR, you can use the bayer drizle option presented here:

http://pixinsight.com/forum/index.php?topic=7184.0


Regards
Geert

[fulatoro]

Thank You Geert. I am using that option. The issue is that with a fullframe images after drizzle, you are looking at 9000x5000 pixels images.  My question was whether or not one should resize the image before processing or simply start the processing and go get coffee :-).

Some of the operations on such large images can take quite a while.  Was just wondering what most people do when dealing with large images. I do crop the originals off course which does reduce the size but still.

Moussa

[fulatoro]

maybe it makes sense to use super-pixel debayering and then drizzle? the full-sized files from the camera are interpolated anyway, so maybe the drizzling would be a better way to recover the full-frame image than the interpolation that takes place during debayering. super-pixel debayering does not do any interpolation at all, so the RGB files are 1/2 the height and 1/2 the width of the sensor.

rob

Rob,

Unfortunately, I am not in a position to truly respond to your suggestion...I was hoping some of the old hands could...

Moussa

[pfile]

ok, i didn't realize you were already using Bayer Drizzle.

generally speaking, drizzle trades noise for spatial resolution. so if you downsize your image after drizzle, you just destroyed the spatial resolution you gained, and it's not clear that the noise in the resampled image will be equivalent to the noise if you had not used drizzle at all. if the noise is higher, then i think the whole drizzle/resample process could be worse than just not using drizzle in the first place.

having said all that, since normal debayering involves interpolation, it could be that the drizzle + downsized image is superior to the non-drizzle image.

i think you'll just have to do some experiments to find out the answer...

rob

[Don]

You can also set the Scale to 1 instead of the default 2 when you perform the DrizzleIngegration process.  This will give you at least some of the benefits of drizzling without increasing the image size.  It will be up to you to determine if the benefit of drizzle integration is worthwhile in this case.

Don

[jkmorse]

Moussa,

This is why I keep my IPad handy.  Can always check emails and play solitaire while PI churns along 

More seriously, I did what I could to speed up my system and the biggest boost was when I traded out my hard drive for an SSD.  It helped immensely, even with big drizzle files.

For what its worth,

Best,

Jim