Getting the best from On1 Photo Raw and Lightroom Classic

If you would rather head straight to a concise summary, the TL;DR is at the foot of the page — or jump directly to the FAQ.

On1 Photo Raw is a post processing program that in my opinion exceeds the capabilities of Lightroom Classic in many ways. It’s become my default software for both birds in flight and landscape/seascape work. However, I have been using Lightroom classic for 15 years and it houses my complete portfolio and provides unmatched workflow and metadata capabilities and is the basis of my backup system. These two programs have been diverging in recent years, so that On1 Photo Raw no longer acts as a plugin for Lightroom Classic , and once On1 photos are exported to Lightroom, they can no longer be edited in Photo Raw.

In this post I describe a workflow that overcomes both problems. The information provided might also be useful for users of On1 Photo Raw alone.

On1 Photo Raw problems with Lightroom Classic

1. Backup
   • Backup of my portfolio (and associated images from the same shoots) is absolutely key – probably the most important aspect of good PC practice. All my images are stored in a structured file format (by year/month/shoot name), automatically handled by LR on import. All these images are then backed up (four times, one to local portable HD, one to server HD, one to offsite HD and one to the cloud). It’s critical for me therefore that images worked on with On1 are integrated into this backup structure, which means that all files, including On1 files have to be stored in the LR folders and not elsewhere.
2. File names
   • Because (unlike Lightroom) On1 allows you to start editing without import, the temptation is to do just that, using the “DSC9937.ORF” type RAW file name straight out of camera. However, one of the benefits of LR is giving a descriptive file name on import. When that is done, it is almost impossible to match the edited On1 file to the imported LR file because the names are different. So you have to match the naming between On1 and Lightroom.
3. Editability
   • Once a file is exported from On1 to LR, it is no longer re-editable in On1, because all On1 layers, effects, and other edits are lost/flattened in the export. For simple Bird in Flight edits, this is not so much of a problem. But when hours have been spent in on a single landscape or seascape image, losing those edits is a huge problem. The ideal is to be able to edit the exported image in Lightroom, but also to still keep an On1 editable file.
4. Interoperability
   • Earlier versions of On1 Photo Raw had the ability act as a plug-in from Lightroom. However, the 2022 version of Photo Raw does not have this capability, in a very user-unfriendly attempt to sell separate stand-alone versions of the software. There is a work-around hack, but a little bit of setup work (one time) is required as shown in this article and video. It’s also a single photo process, and does not work well in batch (say for 200 images).

On1 and LR file formats

A key to solving the problem is understanding the file formats used by On1 and LR. Here’s how that works.

• On1
  1. RAW file. On1 uses a non-destructive process for the most part, so it will use the .ORF or .NEF file for this. These files are readable by Lightroom and On1 of course. But On1 stores the edit information in a separate file.
  2. ON1 file. The edit information about a RAW file is stored by ON1 in a sidecar file with the same prefix, but a .ON1 suffix. This is an absolutely critical file, and must not be lost, or the edits cannot be recreated. It is not readable or even recognised by Lightroom.
  3. XMP file. The metadata about an image (locations, ratings, keywords, IPTC, EXIF etc) is stored by ON1 in a .XMP sidecar file, readable by Lightroom (see Lightroom note 2 below)
  4. ONPHOTO file. If several images are combined in layers (or one image is duplicated into layers) in On1, a new and enormous file is created. This is necessary so that all the images can be worked on together for masking etc. A 55Mb Nikon Z7 NEF goes to 350Mb if used with 3 layers for example. The same file expansion happens with Photoshop or any other layering software, but it’s critical to be aware of this. If you wish to re-edit or revisit the layers, this file must be retained. Once again, this file is not readable or even recognised by Lightroom.
• Lightroom
  1. RAW file. LR uses a non-destructive process so it will use the .ORF or .NEF file for this, and will read the same file that has been used by On1. However Lightroom edit information is usually stored in its catalogue (which is why the import process is needed).
  2. XMP file. By default, Lightroom stores edit and metadata information about an image in its catalogue, but you can explicitly tell LR to store this information in a separate sidecar .XMP file as well (useful for interoperability and as a backup to the catalogue). If you do, the XMP file can be read and changed by both LR and ON1, but testing seems to show that editing is unaffected if this file is changed by either or both programs, and LR and On1 both recognise metadata changes made by the other program into the XMP file.

Key takeaways on using LR and On1 together

1. You have to keep all the ON1 files if you want to be able to edit after the post processing is over
2. All the On1 files have to be transferred into the LR data store, if that is your central backup point.
3. You don’t need to store or back up the On1 catalogue as all the edit info is in the sidecar files
4. You need to keep file names identical through the process, and not have different names in On1 and LR

On1 Photo Raw workflow with Lightroom Classic

The workflow is based on the detailed process I describe in this post. I recently used it to process these long exposure seascape images, some of which were extremely complex in production. The basis of the workflow is that instead of starting with Lightroom (LR) I finish with it. Here is how it runs.

1. Select files for editing in FastRawViewer
2. Save selected Raw files in scratch/temp folder on main PC system
3. (Optionally denoise in DxO prime, and export as DNG back to scratch disk)
4. Open Raw/DNG files in On1 and rename all files in numbered sequence with descriptive text (my format is {date} descriptive text {sequence number})
5. Edit in On1 using layers and local masking etc.
6. Rate all portfolio images with 4 stars
7. Export all selected files to DNG (Adobe standard RAW format) to scratch disk and resize/denoise as appropriate in the process
8. Copy (not import) all raw files and all On1 sidecar and special files (see below for list of files) to the LR directory that LR would use (based on year/date)
9. From the same directory, import RAW and DNG files that appear in LR import dialog, into Lightroom without changing the file name
10. In LR apply keyword and IPTC metadata to portfolio images and complete LR workflow.
11. Backup LR data store as normal.

One problem at the moment is that On1 Photo Raw 2022 does not support the spiffy new OM1 camera, whereas LR seems to be able to at least read and edit them. So for a temporary solution, OM1 files could be imported into LR as ORFs and then immediately batch exported to On1 as DNGs. For those who don’t own Lightroom, the free Adobe Digital Converter software can convert OM1 files to DNG, and these can then be read happily by On1 Photo Raw 2022.

Annoyingly the new (free) OM Workspace product does not support DNG export, and I find it slow and unintuitive, so I recommend the Adobe route above.

Why not completely take the plunge?

The workflow would be a lot easier if I never left On1. However, what to do with the15 years of Lightroom work is a problem. Either I would have to leave the whole LR portfolio to that date stuck in time (and only accessible with LR, which would still require a subscription), or I would have to migrate the entire LR catalogue and all the photos to On1. That’s still a step too far for me for these reasons.

1. Adobe is a huge company and is probably never going to go away. It’s got a massive subscription revenue stream from dozens of products that enables it to survive any individual business hiccup. Its also too big to be bought. On1 on the other hand is tiny by comparison, is dependent on a single product, and could easily be bought. A similar player in the market many years ago used to be Nik software. Google bought it, destroyed it, and left it by the wayside. The tattered remnants were later picked up by DxO, but product development effectively ended the day Google came on the scene (it’s still a great product, but functionally unchanged from 2012 in most areas). I don’t want to risk my whole portfolio and catalogue on some currently attractive software features in On1 and then find it’s disappeared.
   
2. There are still a few things that I can do in Photoshop that I can’t in On1. Content aware fill is the biggest of these. I use this mostly to move a bird from the edge of a frame to the middle of the frame using CAF to create the missing space to the left or right, and it’s brilliant. There is also the amazingly powerful TK8 luminosity masking from Tony Kuyper, which no other program can match. If I have to have Photoshop anyway, I may as well have Lightroom.
   
3. On1 performance is only just acceptable on my pretty fast 2021 gaming laptop. If it gets worse, I may have to stop using it. I am told by a senior On1 development exec that the M1 Macs run On1 very well, so that may be solution for some. But I am not ready to be consumed by Beelzebub in the PC space just yet.

As long as On1 continues to outpace Adobe (and my laptop can keep up) I’ll stay with Photo Raw, and I’ll make the final move from LR at some point in a few years probably. In the meantime, the workflow above suits me just fine, and is no less complex than bouncing between Lightroom, Photoshop, and Topaz, as very many professionals still do these days.

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TL;DR

• On1 PhotoRaw 2022+ does not work as a Lightroom plugin: Must run as standalone software, making integration complex but not impossible
• On1 files cannot be re-edited after Lightroom export: Save sidecar files (.ON1, .ONPHOTO) alongside RAW files in LR directories to preserve full editability
• Backup strategy requires keeping On1 sidecars in LR folders: All .ON1, .XMP, and .ONPHOTO files must reside in the same LR directory structure for proper backup and restoration
• Workflow starts with On1, ends with Lightroom: Edit in On1 with layers/masking, export DNG or RAW, copy sidecars to LR folders, import to LR for final metadata and keyword management
• File naming must match between software: Use descriptive, consistent naming (e.g., YYYYMMDD_description_##) to avoid orphaned or duplicated files during import/export cycles

Back to the article.

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Frequently asked questions

Why did On1 stop supporting Lightroom as a plugin?

On1 Photo Raw 2022 and later versions no longer function as a Lightroom plugin. This change forces users to choose standalone On1 workflows. While this increases friction for existing Lightroom users, it reflects On1’s business strategy to promote standalone use and encourages migration away from Adobe.

What happens to On1 edits when I export to Lightroom?

On1 exports flatten all layers, effects, and masking into a final RAW or DNG file. Once exported, the layered edits are lost. However, if you preserve the original .ON1 and .ONPHOTO sidecar files alongside the exported image, you can still re-edit in On1 later by reopening those sidecars.

Which sidecar files must I keep to preserve On1 editability?

.ON1: Contains all On1 edit information (critical). .ONPHOTO: Created when layering multiple images; essential if re-editing layered compositions. .XMP: Metadata file readable by both On1 and Lightroom. Always preserve all three alongside RAW/DNG files.

Can I edit On1-processed images in Lightroom without losing edits?

Yes. Once exported as DNG or RAW, the file is Lightroom-editable independently of On1 edits. However, you cannot round-trip—Lightroom edits to an On1-edited file won’t sync back to the original .ON1 sidecar, so keep both version streams separate in your backup.

How do I back up an On1/Lightroom hybrid workflow?

Place RAW files + all On1 sidecars + Lightroom catalogue in the same folder structure (organized by year/month). Back up this single directory tree 3–4 times (local, portable HD, offsite, cloud). This ensures On1 editability is preserved on restore, and Lightroom catalogue remains in sync with files.

Should I migrate completely away from Lightroom to On1?

Not immediately. On1 is a smaller, single-product company and could be acquired or discontinued. Adobe is massive and unlikely to disappear. If you have 15+ years of Lightroom work, the cost-benefit of full migration is unclear. A hybrid workflow lets you retain Lightroom as insurance while enjoying On1’s superior editing capabilities.

Back to the article.

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