Panoramas taking up excessive space in Lightroom

[militarybrian]

Hello,

I just downloaded Lightroom CC and I have 15 raw files that I am trying to combine into a Pano via lightroom. I am not using the GPU to speed up the process so its very cpu intensive. I get that raw files are bigger than jpegs. But there is no reason why when I try to create a pano it takes 20 gigs and counting to create a single Pano. Any help in understanding this would be helpful. I don't even know where to start to get it working.

[dj_paige]

But there is no reason why when I try to create a pano it takes 20 gigs ...

20 gigs of what? Memory? Disk space?

How big (in megapixels) are the original raw images?

Since there are very few options you can set when creating a panorama in LR, I think there is a reason for all of this, that's the way the panorama algorithm in LR does things.

[militarybrian]

20 gigs of HDD space. Each photo is 16 megapixels. I actually get to the point where it eats up my the HDD space and gives me the it cant finish cause of low space.

[JP Hess]

How large are the raw files? I created a panorama consisting of 21 raw files (24 MP files, averaged about 24 MB each) and the finished DNG panorama is 485 MB.

Added later. My response was posted after you made your clarifications. How much free disk space do you have? That might be a contributing factor in this case.

[militarybrian]

32 MB each, even with that plus a little overhead a I would be fine with a 1GB file. It just seems to keep eating away at the storage though

[militarybrian]

I think my question might actually be obsolete now. From the looks of it Lightroom doesn't understand the 360 Panos which I am trying to create anyways for this project. Am I correct in saying that?

[JP Hess]

Never tried a 360, but I don't think that's the problem. If you're getting a low disk space warning you probably don't have enough disk cache space available that Lightroom needs to complete the panorama creation process. You could try increasing your Lightroom disk cache.

[Conrad C]

Just curious, how much RAM is installed in your computer?

[militarybrian]

I'm sitting at 10GB currently. I will increase the photo cache. But that still doesn't explain how the photo cache is using 10-20GB of storage when the default cache is 1GB. I am able to sit and watch my C:\ Drive just tick down as it creates it.

[Conrad C · Accepted solution]

OK. Here's my theory.

I'm guessing that merging the panorama might need more RAM than your computer has, because it sounds like what you are seeing is Lightroom asking the OS for more RAM, because if it isn't there, the OS must start consuming drive space to use as temporary virtual memory.

Using my laptop with 16GB RAM installed, I ran a test on a panorama I have that's 13 raw images, 20MB each, with some other applications also open. Total RAM (all applications) use jumped from around 9.5GB before the merge to peak at 13.5GB and back down around 8GB when finished. Virtual memory swap file use jumped from 41MB at idle to 422MB during the merge. This is pretty typical of how RAM behaves when I merge panoramas. But I usually don't see a significant drop in the amount of free drive space. I think this is because my system has enough RAM (16GB) to perform the entire panorama in RAM without going to virtual memory.

Your raw files are larger than mine, and you have more of them. It’s reasonable to assume that during a pano merge, your RAM usage would peak higher than mine. With 10GB RAM installed on yours, the system would definitely have to start using drive space to complete the merge, and since total system RAM usage during my merge was almost 14GB, 20GB is not out of the question for yours. VM is temporary so the system will eventually release the drive space used up during the merge, but if you want to get that space back right away, restart your computer.

It might not be the Lightroom disk cache…on my laptop it's only set to 1GB (I set it much higher on my desktop since the drive is larger there).

And by the way, while I didn’t lose any drive space when merging my 13 images in Lightroom, when I tried this in Photoshop I temporarily lost around 10GB of space to the VM swap file. So Lightroom may actually be doing this more efficiently than Photoshop.

[militarybrian]

Ok, That makes sense, didn't know Lightroom created VM by eating up HDD space. It wouldn't be an issue if I had a bigger SSD. Im only running on a 64GB one currently. Looks like I might have to invest in some more RAM and a bigger SSD. I have a newer GPU coming that runs opengl 4.5 and DirectX 12, so I can use the GPU to help as well.

Thanks for clearing that up Conrad

[Conrad C]

militarybrian  wrote

Ok, That makes sense, didn't know Lightroom created VM by eating up HDD space. It wouldn't be an issue if I had a bigger SSD.

To be precise, it's not Lightroom directly eating up the space, Lightroom is just asking the OS for more RAM and when it isn't there, the OS starts using available drive memory as a RAM substitute. In other words, the OS does that for any program that needs more RAM than is available, it's not Lightroom specific. Anyway, you're right that a drive with more free space would help.

[Martin326291356lv2]

Thats the thing, you just saved me!! I restarted my laptop and got 82GB space back...!!!