Question for DSLR owners - how much data do you keep?

[jsines]

(Not sure if this also applies to CCD owners, because I don't own one, but it might)

I have been using PixInsight for about 3-4 months now.  I've been careful about throwing away any images, but I'm starting to wonder about this.

For each session, I take lights and flats.  If the temperature is roughly the same, I'll reuse a master dark from a similar temperature/exposure length.  I also have a master bias.  I run these through the BatchPreProcessing script, and I end up with the registered frames.  I'm wondering if there is a reason to continue keeping the lights and flats?  I usually throw out the darks and bias after making a master of each.  In my limited time with PixInsight, I haven't found a reason to "re-register" the lights and flats again.  However, I'm new to this, may be missing some important process, so any advice would be appreciated.

When I used DSS, it made sense to keep everything because DSS continued to use them to make the master tiff file I imported into Photoshop.  But in PixInsight, everything is replaced with a registered image.

For me, it's not an issue with data storage, I've just noticed I never re-use the lights.  I've used star alignment to integrate multiple nights of the Orion Nebula, for example, but I've used the registered frames from multiple nights, never the lights.

Thanks for the input!
Jeff

[chris.bailey]

I keep everything and I always keep a copy of all the calibration frames used to create each image in with the light frames. The reason is every so often a new method comes along and it pays to go back over some of those old images using the new method. If you throw aways some of the calibration frames, you limit the ability to do this.

Chris

[jsines]

Thanks!  I appreciate the feedback.  I wasn't thinking about the possibility that new methods may come along that I'd like to try.

[pfile]

yeah me too, i save everything. keeps seagate in business.