Piers Palmer:
Thanks all - much appreciated. I was wrong; I have 16gb of Ram but something is clearly amiss. Autocad and photoshop would have been running so that could be eating into the amount available?
I need a separate imaging computer!
To your point that I copied above, you may not need a new separate computer. My experience with WBPP has been mostly good, but on some occasions, it does cause my system to crash and reboot. Typically, this is during the drizzle integration step. As suggested above, it is likely due to limited resources (RAM) on my machine. I do have a lot of RAM, but I also often initiate a WBPP session while doing other work on my computer. Each additional application opened on the computer reserves a certain amount of RAM and adds "stress" to the RAM. In particular, I find that the Aladin app will cause a crash. It is a RAM hog. And it is known that once opened Aladin, even if closed, somehow still impacts the RAM. So, I now reboot my computer prior to starting a run and I have few if any problems in such a situation. So try doing such intensive work on a computer that is newly booted. And don't browse, etc. while it is running. If it then fails, you will need to upgrade your system. Be sure to configure the swap files as per the PI instructions and if working with an old spinning hard drive, you will need to at least add an SSD for those swap files.
Certainly, ensure that your computer is up to the task for any of the PI functions that are used within the WBPP script. There is nothing within WBPP that inherently will cause a failure of your system to execute that doing each function separately will solve. After all, WBPP only really executes one function at a time. I think the comments to not use WBPP and go with doing PP using each individual function is kind of an odd suggestion (per the PI phylosophy, see below). But I will add, that I do not completely disagree with this suggestion. If you learn the PP process using each script separately, you will learn and better understand just what it is you are doing along the process train and learn what each option does to affect the outcome. This also, depending on the data you feed into the process. A valuable lesson to be learned!
However, the understanding of the Pre-Processing "process" was precisely the reason for the creation of WBPP! If you read the early threads upon release of WBPP, the feedback to questions by the PI insiders was that you should only use WBPP as a means to learn how to do PP. Or at the very least, it should only serve as a means for the knowledgable to do simple "quick and low effort" integrations just to see how the data will look. The expectation being that one would alway, always go back and redo the PP manually. In light of these facts, it is odd that anyone should suggest not to use WBPP as a starting point. However, what I disagree with is not that advice, but PIs' experts' point of view. I find PI in this regard to be very disingenous and elitist (from a photo processing perspective)! WBPP is written in a way that you can set up a calibration/integration quickly in the same way you would do it manually. It also saves much of the actions chosen and outcomes in a log file that the beginner can review. It also saves many of the intermediate calibrated/registered image files for the beginner to review, so that if something goes wrong, you can trace back to where it went wrong. So in that, it certainly works as a very good, logical learning tool. BUT, that can also be done (maybe better) when using each script individually. What I find as disingenous is that if one can set up WBPP to work well, and if one does understand just exactly what choices are made by the user within WBPP, then why would a user
not use WBPP as a primary PP tool?
Assuming you get your hardware system up to the task, as far as PP goes, whichever path you take to understanding what each step accomplishes and how those relate to what you want to achieve in the end, you should learn that you can take a path where you sit at the computer and execute each step individually, wait for the process to execute and then go on to the next step,
or you can set up WBPP to do the exact same processes, hit the "go" button and walk away and get on with your life! If I see two finished images that both look great, one done by individual effort and one done by WBPP, I could care less which choice was made. AstroBin doesn't ask us to list which way we do PP.
For those that use PI as their choice to do PP, anectdotal evidence suggests to me that many here, if not most, use WBPP as their primary and as they wish, not as the PI WBPP founders suggested. And my guess that with the many updates and upgrades to WBPP over the years, it is clear that even PI has succumbed to the concept of using WBPP as a primary tool for PP.
BTW, when my WBPP crashes at the Drizzle Integration step, it is a trivial fix. WBPP, saves the registered images, the drizzle files and even the normalization files and I just then go to the Drizzle script in PI and do the Drizzle integration manually. It then never fails.
I also have used the WBPP often to troubleshoot issues in the final results. It is easy to read the log file, and also to open the intermediate calibrated/process/debayered/etc. files and just look and see the results. But I agree with those who say you should learn the process by starting out by doing each step individually and learning that way.
Bottom line, do the best to learn what is going on. Generating a history of experience with success and failures is the best learning experience. Choose how you do your processing based on
your outcomes and desires. Remember these are your choices. Never feel forced to make changes based on guilt or other non-objective pressures. But, solicit and review comments and criticisms and try different things you see and fold them into your process as you have time and energy to do so. This takes time and should never cease as a process of improvement.