Moving files from CCD Stack to PI

[andyc67]

This has been marginally discussed before. I am trying to debloom my FITs first with CCD stack and then calibrate/process as usual with PI. I have no idea how CCD Stack saves FIT files but I can not make PI work with the output from CCD Stack.
It will work if I save the files in 16 bit TIFF format.
Rather than dealing with figuring out how the FITs are saved I prefer this route. However, are there any downsides to doing this?

Thanks!

Andy

[jkmorse]

Andy,

First things first, I strongly encourage you to move over entirely to PI and stop using CCDStack.  You get much more control and far better results in PI.  I have a cribsheet that walks you through all the details if you are interested.  Just send me an email at jkmorse57@gmail.com and I will be happy to send it along.

As to TIFFS, the downside risk is that you will want to be in 32bit space as you process your images.  I know Photoshop works in Tiff space, but you are losing depth of image which as a part of processing often well exceeds 16bits.  As such, once you get those images into PixInsight and working, convert them to 32bit floating point files as soon as you can, preferably in the .xisf format (though straight 32 bit floating point FITs works as well).

Only other thing you are surrendering is the information in the FITs header which is all lost when you convert to TIFF.  No a terrible loss, but something to consider.  Note I have tried to help folks experiencing this problem in the past.  Check out this post:

http://pixinsight.com/forum/index.php?topic=8021.msg52728#msg52728

Best,

Jim 

 

[andyc67]

Thanks Jim!
I actually have been using PI only for a few years now. The issue is that I can never get a good bloom rejection, even when I do HDR composition using different length exposures. CCD Stack does a very nice job rejecting blooms, of course there is some data loss but the effect is aesthetically pleasing.
Here is an example of a bloomed star that I tried to mitigate with HDR composition in PI. I will start a new thread about this topic.

Andy

[jkmorse]

Andy,

I will be really interested in that thread.  I have been toying with the idea of upgrading to the SBIG STXL 6303E which has a nice deep 100,000 count well and good QE at the cost of no deblooming.  Finding out how to fix those blooming stars in PI would be great.

Best,

Jim

[cardiofuse]

I deb loom in CCD Stack as it is flawless and save as floating point 32 and PI opens them fine.

I'm evaluating PI and the deb loom this is whats hold me back as my camera ST10XME will bloom under most long exposures.

[andyc67]

Interesting, I wonder why it's not working for me. I'll look further into it when I get home this coming Friday. I might ask you for what settings you use on both programs if you don't mind.
One o my CCDs is the qsi532 which has the same chip as yours.

Andy