Build one master photo library

Applies to: Photo Date Rescue for Windows, version 3.0.4. Last verified: 28 July 2026. Every statement on this page was checked against the shipping 3.0.4 build. If you are on an older or newer version, the behavior may differ — check What’s new for changes.

This page is the reference we cite from our comparison table. Each capability below has its own permanent link, so a claim about PDR can always be traced to the paragraph that supports it. Where the answer is “no” or “only partly”, this page says so in the same words the comparison uses.

A note on vocabulary, because this page uses three words precisely:

• Sources — the folders, drives and export archives you point PDR at. PDR opens these for reading and never writes to them.
• The Library Drive — the destination you choose. This is where the master library is built.
• The library — PDR’s own database of dates, faces, places, albums and history, which lives on your PC and mirrors itself to the Library Drive.

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At a glance

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Measuring the collection before you start

Yes. Before you run anything, PDR shows the size the run needs against the free space on the drive you chose — “Required: 84.2 GB”, and then either “212.1 GB free after this fix” or “Insufficient space”. The figure is added up from the real byte size of every file the scan found and adjusted for the output format you picked, so it is a measurement rather than a guess, and it recalculates the moment you tick or untick photos or videos. It is deliberately a slight over-estimate: duplicates the run will skip are still counted, so the check errs towards warning you rather than surprising you. What it cannot measure is a collection you have not found yet. If half your photos are on a drive still in a drawer, that drive is not in the number.

To do it

1. Add every source you want in the library — folders, external drives, or Google Takeout export archives.
2. Let the scan finish. Until it does, there is nothing to add up.
3. Tick or untick photos and videos, and choose the output format. The total changes with each, because the estimate is recalculated from the files themselves.
4. Read the size shown against the destination before you run anything.

Limitations

• It measures sources, not collections. The total covers the sources you added and ticked. Add another drive later and the number goes up; PDR never claimed to know about it.
• Room to grow is a separate question, and it is answered from what you told us. The measurement above covers this run. Advice about how big a drive to buy comes from the planner instead, which asks you to pick a size band and adds headroom to it — see choosing which drive should hold the library. If your band is wrong, that advice is wrong with it; the measurement of this run is not affected.
• The planner’s answer is remembered in your browser profile for the app, not in the library, so it does not travel to another machine with the library.

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Checking the destination, and what happens to your files

Yes. PDR reads the free and total space on the drive you chose and refuses to start a run that will not fit: the Run Fix button switches off and the screen says Insufficient space on destination. And there is no ambiguity about what a run does to your files. A Fix always writes fresh copies to the destination and always leaves the sources exactly where they are. Nothing is moved, nothing is merely referenced, and nothing at the destination is overwritten.

To do it

1. Choose the destination folder. Pick a different physical drive from your sources.
2. PDR reads the free space on that drive and compares it against the measured size of the run.
3. If it does not fit, the run is blocked until you free space or choose elsewhere.
4. Run the Fix. Copies are written into year folders at the destination.

Limitations

• A disconnected drive is blocked but badly labeled. If the destination cannot be reached at all, the space probe returns zero, so the run is still correctly refused — but the screen keeps reading Calculating space… instead of telling you the drive is missing. The explicit “reconnect your Library Drive” message exists only on the path that unpacks ZIP and RAR archives.
• The check is against free space at the moment you look. It is not a reservation, so something else filling the drive mid-run is not caught.

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Leaving the originals, sidecars and Live Photo pairs alone

Only partly — and the part we fail matters. Your original files are genuinely safe: sources are opened for reading only, and when PDR stamps a corrected date into a photo’s embedded metadata it stamps it into the copy on the Library Drive, never back into the file you came from. But the master library PDR builds is not a faithful mirror of what you gave it. Two things do not make the journey.

What does not come across

• Sidecar files. PDR collects photo and video file types. Lightroom and digiKam style .xmp sidecars, and Apple .aae edit files, are not among the types it collects, so they stay behind on the source drive. If your keywords, ratings or crops live in a sidecar rather than inside the image, they are not in the library PDR builds. PDR does read XMP that is embedded inside a photo; it is the separate file beside the photo that is left.
• Apple Live Photo pairs. Nothing in PDR links an iPhone Live Photo’s still image to its paired video clip. Both files are copied, but each is renamed independently from its own date and confidence, so the shared filename that defines the pair is discarded — even when both halves land in the same dated folder. This applies to Apple’s two-file Live Photos only. Samsung, Google and OnePlus Motion Photos keep their video inside a single image file and are unaffected.

Limitations

• Every copied file is renamed. The new name is a timestamp plus a two-letter confidence tag. That is the point of the product, but it means the library is not a mirror of your folder names, and any external tool that identified a photo by its filename will no longer find it.
• Only photo and video file types are carried across. Anything else in the source folders — documents, notes, the sidecars above — is left where it is.
• Because the sources are untouched, none of this is destructive. The sidecars are not deleted; they are simply not brought along.

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Reviewing and reversing duplicates, collisions and moves

Only partly. Every run produces a report listing each file PDR treated as a duplicate, which file it kept instead, and which method made the call. Name clashes at the destination are resolved by adding a numbered suffix, so a run never overwrites anything it has already written. What you do not get is a review step: you are never asked to approve or reject a match before it happens, and there is no undo button for a completed run.

How to reverse a run

1. Open Reports History and read what the run did.
2. If you do not want the result, delete the copies the run wrote. They go to the Recycle Bin.
3. Your sources are untouched, so nothing needs undoing on the source side. Run it again with different settings.

Limitations

• There is no one-click undo of a Fix run. The reversal above is a manual deletion of output. It is safe because the sources were never written to, but it is not the same thing as a rollback.
• Duplicate matching drops to filename and size in three cases. Normally PDR compares a content fingerprint of the file itself, which catches a copy that has been renamed. It falls back to the weaker filename-and-size test for files over 500 MB, for sources it recognizes as a network or cloud-sync drive, and for files already sitting at your destination that PDR has not indexed yet.
• The “thorough duplicate matching” setting does not override those three cases in 3.0.4. Its label reads as though switching it on forces the content fingerprint everywhere. It does not — part of the pipeline never reads the setting at all, so the fallbacks above still happen with it turned on. This is a defect we have recorded, not a subtlety. Until it is fixed, plan around the fallback rather than around the toggle.
• The duplicate report is a record of decisions already taken. Nothing pauses the run to ask you.

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Surviving a change of drive or computer

Yes. A hidden folder on the Library Drive holds a running copy of the catalog, the correction log and recent database snapshots, refreshed roughly every thirty seconds whenever there is something new to save. Plug that drive into another computer, install PDR, and choose restore: the catalog is copied onto the new machine, and if the drive has come up under a different letter the stored file locations are rewritten to match, so the links to your photos still resolve.

To do it

1. Install PDR on the new machine and enter the same license key.
2. Connect the Library Drive.
3. Choose restore. PDR takes a snapshot of whatever local catalog exists first, then copies the drive’s catalog over it.
4. Dates, faces, albums and history come back without re-importing or re-analyzing anything.

Limitations

• The restore requires the same license key that set the library up. This is deliberate — it stops a stranger who finds your drive from opening your library — but it does mean a lost key is a lost restore.
• The mirror only runs on the machine holding the write lock. If two machines share a Library Drive, only the one that currently has the lock is saving to it.
• The drive-letter rewrite covers the two places PDR stores paths: where each indexed photo is, and where each run wrote to. Paths held anywhere else are not remapped.

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Leaving with your originals and your metadata

Yes. The master library is ordinary folders of ordinary files on a drive you own, and by default the recovered date is written into each photo’s own embedded metadata — so the dates travel with the pictures into any other program without PDR being installed. On top of that, a cumulative spreadsheet is written to the top of the Library Drive by default, listing every file’s original name, new name, source location, confidence, and how its date was determined.

What you can walk away with

• The photo and video files themselves, in plain year folders.
• The corrected dates, inside the files, readable by anything.
• PDR_Catalogue.csv and PDR_Catalogue.txt at the root of the Library Drive, mapping every new filename back to where it came from.

Limitations

• The dates PDR is least sure about are not stamped by default. Files marked low-confidence keep their date in the filename and in the spreadsheet, but the embedded metadata is left alone unless you switch that on. That default is deliberate: we would rather leave a field empty than write a date we cannot stand behind.
• The spreadsheet describes date work only. Faces, names, tags and family-tree data have no equivalent export and remain inside PDR’s own catalog file.
• The spreadsheet lists files that still exist on the drive, so files you deleted by hand drop out of it.

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Where processing happens, and what leaves the machine

Only partly. The important half is true and unqualified: all the work happens on your computer, there is no cloud storage, and no photo or video content is ever uploaded. There is no code path in PDR that sends image data off your machine. Even the “send to phone” feature runs a short-lived server on your own wi-fi rather than through anyone’s service. What holds this section short of a clean pass is narrower: PDR is not usable with no online steps at all.

There is no PDR account. No sign-up, no email and password, no profile, no login. The only credential anywhere in the app is a single license-key box, and our in-app wording claiming “no account” is accurate. Your license key is issued by our payment provider, which needs an email address to send it to you, so you are not anonymous — but that is a receipt, not an account.

What actually leaves your machine

• Your license key and an anonymous machine ID, sent once to our payment provider when you activate. The machine ID is a one-way hash; no email, no hardware serial and no file information is sent with it. After activation PDR does not phone home — it re-checks only when you refresh or move a license, and it keeps working offline for seven days. First activation does need the internet.
• A file count, on free trials only. A free trial reports the number of files it is about to process so the trial allowance can be counted. The message contains the key and a number and nothing else — no device details, no filenames, no dates. A paid license sends nothing.
• Optional AI model downloads, if you enable a feature that needs one. These are downloads to you, not uploads from you. The models then run on your machine; your images are not sent anywhere to be analyzed.

PDR collects no analytics or telemetry of any kind. There is no analytics library of any sort in the shipping build.

What never leaves

• Your photographs and videos. There is no upload endpoint for media anywhere in the product.
• Your library database, faces, names, places and albums.
• Filenames, folder names and paths.

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Choosing which drive should hold the library

Yes. Before you pick a destination, PDR looks at every drive attached to the machine and ranks them for you. It reads each drive’s type and speed, its total size and its free space, compares that against the size of collection you told the planner you expect to end up with, and marks one drive Recommended. It also argues against the two choices people most often make by accident. Your Windows system drive is pushed to the bottom of the list, with the reason spelled out: a growing photo library takes the space Windows needs for updates and virtual memory, and that causes crashes and boot failures. A network location is pushed down too, as too slow and unreliable to process a library across.

To do it

1. Answer the planner’s question about how large you expect your collection to become. The advisor needs this to judge whether a drive has a future, not just a present.
2. Open the Library Drive Advisor. It appears on its own when you are choosing or changing a Library Drive.
3. Read the ranked list. Each drive shows its type, a space bar, an estimated copy time, and any warnings that apply to it.
4. Choose a drive. Choose Library Drive confirms it.

Limitations

• It advises; it does not refuse. The system drive and network locations are heavily penalised and carry explicit warnings, but if you read the warning and choose them anyway, PDR lets you. We think that is the right way round, but it does mean the advisor cannot save you from a determined bad choice.
• The advice is only as good as your answer about size. If you skip the planner question, the advisor only knows about the run in front of it. A drive that comfortably fits today’s sources can still be the wrong long-term home, and without your figure the advisor has no way to say so.
• Recommended means it fits the whole collection. A faster drive that holds only part of your expected library will not be marked Recommended, even though it would be quicker for the run in front of you.
• Drives are read when the advisor opens. It does not keep watching, so a drive unplugged after you have chosen it is not noticed here.

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Bringing folders, drives and export archives into one run

Only partly — and the gap has a name. Loose folders, whole external drives, ZIP and RAR archives and Google Takeout exports can all be added as sources to the same run, and you do not have to unpack or tidy any of them first. PDR opens both a ZIP and a RAR itself, with nothing else installed. It recognizes a Google Takeout export for what it is and reads the JSON records inside it. A large archive is extracted to working space on the destination drive rather than your system drive, so unpacking a Takeout does not fill up Windows. What holds this short of a clean pass is a ceiling on how much can sit unpacked at once, and what it explicitly does not do is understand an Apple export.

To do it

1. Add each source in turn — a folder, a drive, or an archive file. There is no limit on mixing types in one run.
2. Let the scan finish. Archives are extracted during this stage, so a large Takeout takes a while before anything else can happen.
3. Check the totals, then choose your destination and run the Fix.

Limitations

• Only ZIP and RAR are unpacked for you. Both are handled by PDR itself and need nothing installed. A 7z, tar or any other archive is not recognized as an archive at all — unpack it yourself and add the resulting folder instead. RAR needs no WinRAR installation; 3.0.4 carries its own extractor.
• There is no Apple or iCloud importer. PDR understands the structure of a Google Takeout export and reads its metadata records. It has no equivalent for Apple. Photos exported from iPhoto, Apple Photos or iCloud are still processed — PDR reads the files themselves, which is where an Apple export keeps its dates — but there is no album or metadata file being parsed, so nothing beyond the files survives. See what actually happens to an Apple export.
• Working space comes out of the destination drive. Extracting a large archive needs room for the archive’s contents on top of the finished library. A destination with just enough space for the result can still run out during extraction, and that failure is reported separately from the ordinary space check.
• There is a ceiling on how much can sit unpacked at once. PDR keeps unpacked archives in working space until you run the Fix, and refuses a new archive once about 55 GB is already waiting there, asking you to run your Fix first — which clears the space. A very large multi-part Google Takeout therefore goes in as two or three rounds of add-then-fix rather than one. Only one archive over 2 GB is unpacked at a time; add a second and you are asked to wait for the first to finish.
• An extracted archive is not verified against its own manifest. A truncated or corrupted archive can produce fewer files than it should without PDR saying so.
• Dropbox, OneDrive and other services’ own export formats have no special handling. They are read as ordinary folders.

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Tracing a renamed file back to where it came from

Only partly — it is all recorded, and only some of it is shown to you. PDR renames the copies it writes, and it keeps the thread back. For every file in the library it stores the original filename it arrived with, the path it came from, and the source the date was taken from — whether that was the photo’s own EXIF, a Google Takeout record, the filename, or your own correction. The confidence is written into the new filename too, as a _C, _R or _M suffix, so a folder of finished files carries its own summary without PDR open. Searching finds a photo under its original name as well as its new one. The shortfall is that most of this is stored rather than surfaced.

To do it

1. Open Memories, then Needs dates. Select a file.
2. The panel shows the current date alongside where it came from, so you can see the reasoning before you change it.
3. To find a file by the name it used to have, type that name into search. Both the original and the current name are indexed.

Limitations

• The file information dialog does not show it. The original filename and the date source are recorded for every file, but the place you would naturally look — the file details in the viewer — shows neither. Today the date source is only visible in the Needs dates editor, which means you can see the reasoning for the files PDR was unsure about and not for the ones it was confident about.
• There is no per-decision audit trail. PDR records that the date came from EXIF, or from a Takeout record. It does not record which tag, which record, or which of several candidates it preferred and why.
• The confidence suffix on the filename is yours to remove. If you rename files outside PDR the suffix goes, and the on-disk trace goes with it. The database record survives.

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Being stopped before a run that will not fit

Yes. PDR compares the measured size of the run against the free space on the destination you chose, and if it will not fit, the run cannot be started. The Run Fix button switches off and the screen reads Insufficient space on destination. This is a real block rather than a warning you can click past: there is no confirm-anyway path. Nothing is copied, nothing is renamed, and no partial library is left behind for you to clean up.

To do it

1. Add your sources and let the scan finish, so the size shown is measured rather than estimated.
2. Choose the destination. The comparison happens immediately.
3. If the run is blocked, free space on that drive or choose another. The button comes back on its own.

Limitations

• There is no safety margin. The test is whether the run fits, not whether it fits comfortably. A run that needs very nearly all the remaining space is allowed to start.
• It is a reading, not a reservation. Free space is checked at the moment you look. Anything else filling the drive while the run is going is not caught.
• Unpacking an archive is checked separately. The space needed to extract a large ZIP or RAR is not part of this comparison, and running out during extraction produces a different failure at a different moment. See bringing archives into a run.
• If the destination cannot be reached at all, the run is still correctly refused, but the screen says Calculating space… rather than telling you the drive is missing. See checking the destination.

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Running with no account, and nothing uploaded

Only partly, and the part that fails is narrow. There is no PDR account — no sign-up, no email and password, no profile, no login. Your photographs, your library, your filenames and your folder structure never leave the machine; there is no upload endpoint for media anywhere in the product, and the analysis, the renaming and the copying are all local work on your own hardware. What stops this being a clean yes is licensing. A paid license, once activated, runs a Fix with no network at all. A free trial does not: before a run starts it has to reach our service to ask how much of the trial allowance is left, and if it cannot, the run is refused rather than allowed.

To do it

1. Install PDR and activate your license once. First activation needs the internet.
2. After that, disconnect if you like. A paid license keeps working offline, and re-checks only when you refresh or move it.
3. Run scans and fixes normally. No photo, filename or date is transmitted at any point.

Limitations

• A free trial cannot run offline. The trial allowance is counted on our side so it cannot be reset by reinstalling, which means a trial Fix needs a working connection to start. This is deliberate, but it does mean the offline promise applies to paid licenses and not to trials.
• First activation needs the internet, and a license re-check is needed periodically after that. PDR keeps working offline for seven days between checks.
• Some AI features download a model the first time you use them. That is a download to you, not an upload from you — your images are never sent anywhere to be analyzed — but it is a network step, and the models are large.
• PDR checks for updates on its own. It reports no analytics or telemetry of any kind; there is no analytics library in the shipping build.

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Known gaps in 3.0.4

Collected in one place, because these are the things a reader choosing a tool to build a master library most needs to know, and because the same ones appear against PDR on our comparison page:

1. Sidecar files are left behind, and Apple Live Photo pairs are split. See preserving originals.
2. No review step and no one-click undo for a Fix run. The reversal is deleting the output. See duplicates and collisions.
3. Sizing covers the sources you added. The allowance for growth is a figure you supply. See measuring the collection.
4. A license key is required and the first activation needs the internet. There is no account and no sign-in, and photos never leave — but PDR is not usable with no online step at all. See what leaves the machine.

When any of these changes, this page and the comparison table change together, and the “last verified” date at the top of this page moves with them.

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How to check this page is still true

Every claim here describes behavior you can observe in the shipping build. If something on this page does not match what PDR does on your machine, that is a defect in one of the two, and we want to know: contact support. Tell us the anchor — for example /help/plan#preserve — and we will either correct the software or correct the page.