I was trying to create some bubbles. Everything was OK in render preview, but render result becomes completely transparent image.
Here you can see render preview. I use HDRi lighting and film transperant.
First sample in render process shows a bit of "envelope" of each bulb.
Here you can see render at 2-3 samples and it's almost invisible.
here is a gif when render runs...
Here is my node setup. I can upload my .blend file if you help me how to do this:)
Yes, bubbles are visible, but it brings black background and some bugs.
And the most interesting thing i found when i tried to save this image with black background without alpha.
THIS is the saved rendered image from previous screen!
Here is the comparison between rendered image and render preview at 1 sample.
And at 2 samples.