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Lightroom to Photoshop file size becomes massive

Forum|Forum|2 years ago
August 22, 2023
10 replies
1822 views

I was editing an image in Lightroom, and needed to do some quick clean up. So I used the "import to Photoshop" feature in order to do this. I made one copy of the file, and then a new layer. I used various heal tools on the new layer. Nothing exotic on the healing, just removing dust spots. When done with the healing, I made a consolidated stamp layer (al+ctrl+shift+E). I then closed the document to import back into Lightroom. I sat and waited for the image to upload to the cloud so I could edit it. After 2 hours, it still hadn't uploaded. So I just left my computer on and went home. Several hours later, it finally updated. At home, I tried to finish the editing the image in Lightroom mobile, and then export. After pressing the export button, I again waited over 2 hours for the image to download so it could be exported. I simply gave up after 2.5 hours, and just made the changes in Lightroom.

I am now looking at the file in my Lightroom library, and it is 1.15gb. This is massive. The file is saved as a .tif, and I thought that when Photoshop exported the file, it flattened the image into one singular image. This seems to be true, as pressing "edit in photoshop" on that same file opens it as a single image again in Photoshop with all the changes that were previously made saved, and no layers to edit. So if it isn't saving the layers, why is the image so large?

My file dimensions are 6720x4480 (240ppi). The entire Photoshop image was 4 layers, with one of them being a clear new layer used for healing. Photoshop and Lightroom are the latest versions. If I flatten the image in Photoshop, it drops it down to 175mb. Still large, but far more managaeable. I haven't tried uploading this image, as I don't have 4 hours to wait on the file to upload. This seems like a massive bug, as saving just a few of these images would rapidly take up all of my storage. Not to mention that several hours to upload and download 1.15gb from the cloud is a bit crazy. I used my work computer and wifi to upload, and then my phone on my home wifi to download. Both internet services are running at normal wifi speeds.

Correct answer D Fosse

You still misunderstand. The image is not imported "back into Lightroom". Photoshop just saves out to a location on disk like it always does. It saves with layers and everything else.

The reason it reappears in Lightroom is that a background script is running, which tracks the location and imports the saved file into the Lightroom catalog.

A LIghtroom import is not a physical import of the file. It's just a record of where the file is. Similarly, any Lightroom adjustments are not physical adjustments to the file. They are just text instructions in the Lightroom catalog. If you Export from Lightroom, those instructions are applied and baked into a flat exported file.

In short, Photoshop and Lightroom operate on different basic principles. As a one-way workflow from Lightroom to Photoshop this is invisible and seamless. The problems start when you try to reverse that basic flow. It can be done, but you do need to understand what's happening and take the necessary precautions.

K-ozDragonAuthor

Known Participant

Ok that makes more sense, thank you for explaining how it works. Since the workflow is supposed to be streamlined, wouldn't it make more sense for Photoshop to take note that the file is being imported automatically from Lightroom, and will be imported back in as a flat file? Therefore it would make sense to automatically do this in order to streamline the workflow?

As it exists now, I have to flatten the final image in order to stamp all of the layers into one image, thereby erasing all of the layers. Or I have to turn on a setting which seems like it should be turned on by default within Photoshop when importing from Lightroom. As part of a steamline experience, having to setup the program to interact specifically with another program made by the exact same company doesn't make a whole lot of sense to me.

K-ozDragonAuthor

Known Participant

Since this is still getting views, I can actually answer my own question now that I fully understand how this works. Funny enough, I was correct the first time with my initial statement.

When working in Lightroom, your image remains in RAW format (or whatever you're working with). Once it's put into Photoshop, it is razterized. As you add layers to the photo, the file size gets larger. This makes sense. However, the issue is importing BACK into Lightroom. Normally the layers would be stored so they could be open as a complete set of instructions with additional data for modifications made in Photoshop. Which in turn makes the file larger. When you import back into Lightroom, your edits are saved as a rasterized .tiff file. The issue is that the full file size is saved, yet none of the layers are saved or readable by Lightroom or Photoshop. What you get is identical to flattening the image & reducing the file size dramatically - but in actual practice you just get a massive bloated file which takes hours to upload to the cloud & eats up storage space.

So let's say you edit in Lr, then export to Ps. You make a heal layer & an adjustment layer. You save the file & export back to Lr. It will make a new, massive file in Lr. If you decide to edit in Ps again, one would expect your layers to be saved in this huge file - but this is NOT the case. You will just have a single flat image with no saved layers, yet the file size would indicate that there are saved layers. This extra data is totally superfluous & just balloons files which causes hours of uploading to the cloud & storage being eaten up. It is unnecessary.

If you edit a few layers in Ps & export back to Lr, your file will jump from 26mb to 300mb. Edit more than six layers, & you'll have a 1.5gb file. The file keeps growing, yet what you are left with is one single image upon export. So if you use a workflow where you move from Lightroom to Photoshop & then back to Lightroom, be sure to select all layers & flatten your image. This will combine all the layers, which is going to happen as soon as you export anyways, & will drop a massive file down to roughly 125mb or so. The file is larger than the original due to being rasterized & uncompressed, but still vastly more manageable than the gigs of data you would have if the image isn't flattened. So it's still a fairly large file, but way better than gigs of data for no reason.

It seems perfectly obvious that Photoshop should flatten the image before exporting back to a cloud based editor, but it does not. It simply saves a bloated file with information that cannot be used in any way. So just be sure to flatten everything when you save so the file isn't massive in Lightroom. If you want to actually save your layers so they can be revisited & modified later, save a seperate copy of the .tiff file. Also remember that your Photoshop export will be a rasterized file (in a lossless format) & no longer a RAW file. So do as much of your edits as possible in Lr before exporting to Ps. That way you maximize your edits in RAW with all the data, as the rasterized file won't be as flexible.

If anyone needs further clarification, I'm always happy to help. Just drop a reply.

davescm

Community Expert

You are still incorrect in your understanding. Layered files are not 'bloat' but an essential way to save files as master files that you can go on to re-edit again. I use Lightroom Classic and Photoshop daily and always save master files as PSD or PSB depending on file size and of course they are editable.

When you select a layered file in Lightroom Classic and reopen it in Photoshop then you have a choice of three options:
Edit Original - which means open the PSD or TIFF as you saved it. All layers remain intact.
Edit a Copy - which means open the PSD or TIFF as a new copy. All layers remain intact.
Edit a Copy with Lightroom Adjustments - This means any additional adjustments that you made in Lightroom since you saved the file from Photoshop. In this case the file is flattened and the additional Lightroom adjustments applied. In this case the file is reduced to a single layer with those additional Lightroom adjustments applied to the file.

There is however a fourth way which is a better option especially if you are starting with raw files. When you first move from Lightroom to Photoshop use 'Open as Smart Object in Photoshop'. This allows you to re-open the Lightroom adjustments, within Photoshop, by clicking on the Smart object in Photoshop which opens Adobe Camera Raw. When you close the smart object, the image in the file is updated. You can add your layers and save as PSD or TIFF. Another advantage of this method is if you copy that smart object layer (Ctrl+J) you can open, edit, and update any of the copies and all those smart objects will update with the same edits.
Then, to re-edit you can just open as original from Lightroom and make Raw or other layer adjutments as required.

Dave

D Fosse

Correct answer

Community Expert

You still misunderstand. The image is not imported "back into Lightroom". Photoshop just saves out to a location on disk like it always does. It saves with layers and everything else.

The reason it reappears in Lightroom is that a background script is running, which tracks the location and imports the saved file into the Lightroom catalog.

A LIghtroom import is not a physical import of the file. It's just a record of where the file is. Similarly, any Lightroom adjustments are not physical adjustments to the file. They are just text instructions in the Lightroom catalog. If you Export from Lightroom, those instructions are applied and baked into a flat exported file.

In short, Photoshop and Lightroom operate on different basic principles. As a one-way workflow from Lightroom to Photoshop this is invisible and seamless. The problems start when you try to reverse that basic flow. It can be done, but you do need to understand what's happening and take the necessary precautions.

K-ozDragonAuthor

Known Participant

Thank you. I am aware that Lightroom does not read layers, which is why this makes no sense to me. It seems like the image would be automatically flattened upon export from Photoshop when it is automatically imported back into Lightroom. Especially since this is the automatic feature of editing in Photoshop from Lightroom, shouldn't this occur automatically? The fact that it doesn't is why I believe this to be a bug. The image size is being massively inflated, despite the fact that what is being exported is technically a flattened image for Lightroom editing.

D Fosse

Community Expert

LIghtroom does not support layers. It cannot read layers.

A layered Photoshop file has to be saved with "maximize compatibility" on to be visible in Lightroom. This inserts a flattened composite into the file, and this flattened composite is what Lightroom uses.

For this reason, roundtripping via Photoshop back to Lightroom is very risky and a recipe for confusion - unless you fully understand the implications of this.

K-ozDragonAuthor

Known Participant

If it's that basic, it should be easy to explain. I'll just have to wait for someone more intelligent to answer, and hopefully less rude.

Earth Oliver

Legend

Sorry, but everything you believe about how this works is totally wrong. Hopefully someone with more patience will be able to help you from here.

K-ozDragonAuthor

Known Participant

I do have smart layers on two of the images. However, should this matter when the image is imported back into Lightroom? I understand that it would make the file much larger within Photoshop, as I am altering the data and adding more to it. That makes perfect sense. However, when the image is automatically imported back into Lightroom, all of the layer data is lost, as the image is flattened into one final image, and then brought back into Lightroom.

As an example, if I flatten the image within Photoshop, I get a file size of 175mb. When imported back into Lightroom, this stays the same and I get exactly the same image as I do if I don't flatten the image and let Photoshop import back into Lightroom. So why the difference in file size?

Also, if I had edited in 16 bit, that would only double the data to 350mb. It wouldn't make it over 8x larger.

K-ozDragonAuthor

Known Participant

Correct, I understand that within Photoshop, the file size gets bigger the more layers you add because each additional layer is data. However, I'm referring to the file size once the image is closed and then put back into Lightroom. Lightroom does not get those additional layers. They are not stored within the file. If I open the photo again from Lightroom and import into Photoshop, there is just a single image. No layers, no saved data, just a single image. I have done this before with images that had way more data in them, and had up to 13 layers, and the file size once imported back to Lightroom was around 300mb at the most. This was just a copy layer, a very tiny heal layer (done on a clear background), and then a stamp layer - yet it was 1.5gb.

Essentially, shouldn't the image be flattened once it is imported back into Lightroom? If I flatten the image within Photoshop, it becomes 175mb. This is reasonable, as the compression changes from raw to .tif. The file is apparrently flattened automatically when imported back into Lightroom, as all of the layers and extra data are gone. So why would the file be 5 times the original size?

Earth Oliver

Legend

no, that's how adding several layers to an image has always worked... for decades. If you don't want massive files, then don't duplicate the layers several times.
And are you working in 16 bit?

Kevin Stohlmeyer

Community Expert

Hi @K-ozDragon are any of your layers smart objects?

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