The Iris Nebula - my biggest project so far.. and the one where everything went wrong.

August. It started with cloud issues. I lost 4 nights worth of imaging time due to tiny clouds just plopping up right above me... and clear nights are rare in Germany. Even a tiny thunderstorm appeared in the middle of the night out of nowhere. Luckily I was still awake and checked the forecast. That was close.
I did however manage to get 6 hours of total integration time this month. But then it happened... the disk space of my laptop was full. So I got out of bed to free some space and restart the session. But instead of deleting my flats and bias frames folder I accidentally deleted the lights folder. 5 hours of data gone. Due to the size of the folders the files didn't go to the recycle bin. No program was able to restore my files.
September. The moon disappeared and I could get back to imaging. After setting up my telescope I tried to collimate it. The stars looked horrible. Turns out my Hotech collimator was out of collimation and I had to collimate the laser again. But what happened to my guiding? I used to have 0.5"rms and suddenly I couldn't get below 1.2". After updating Phd2 and playing with the settings could get it back to 0.7". The following night my sister knocked at the door to tell me there's a fire nearby. The sky was covered with smoke and the lights of the firefighter trucks were really bright. Luckily nobody was hurt.
Anyways.. I finally got 26hrs of data. I deleted 5 hours due to clouds and guiding errors and started stacking. I usually stack with Astro Pixel Processor. But for some reason it needs 2.5 terabytes of free disk space to stack my 630 images with 2x drizzle. Would be nice if it could tell me that before calibrating, registering and normalizing all the images. So I turned the drizzling down to 1.5x which "only" takes 1.3 terabytes of disk space. The slow HDD had 1.6 terabytes left. The stacking process took over 24hrs just to show me an image without proper calibration and huge vignetting. What happened? Before I stack my images I use the channel alignment in APP to get rid of the atmospheric dispersion on my stars. Then I put the images in Pixinsight to check the quality with SubframeSelector. Pix however converts the images into .xisf files so I had to convert them back to .fits for APP to process them. But somewhere in this process the geometry of the files changed and I couldn't calibrate them anymore. Using SubframeSelector first and then aligning the channels afterwards fixed my issue.
After stacking the images for the 3rd time I ran into a different error. For some reason ASTAP gave me the wrong rotation as I platesolved an image of my August session to get the right coordinates and rotation for the September session (I imaged the planets during full Moon and removed my camera). So 1/3rd of my images had a different rotation and final stack looked horrible due to the light pollution gradients. Luckily APP is amazing at combining mosaics with wild light pollution gradients. All I had to do was to separate the data according to its rotation and stack it all over again.  After 4 days of stacking I was finally able to properly process the data. I've spent a couple hours on the image until I was too tired to process and went to bed. The next day I tried to open my file to finalize my edit and I got the message: "Failed to open. The files appears to be truncated". I couldn't fix the file. What a roller coaster of events.
Anyways, I hope you like the result! Iris is one of my favorite targets so it was worth all the struggles!

Bortle class 4.9