# DNG vs RAW: What Converting Your RAW Files to DNG Changes, Tested on 16 Files > DNG vs RAW, measured: we converted 16 camera RAW files to lossless DNG. The raw data matched; sizes ran from 45% smaller to 93% larger. - Canonical HTML: https://revelraw.com/blog/dng-vs-raw.html - Markdown mirror of this page: https://revelraw.com/blog/dng-vs-raw.md - Published: 2026-11-09 - Language: English - Machine-readable site index: https://revelraw.com/llms.txt · Full site as one file: https://revelraw.com/llms-full.txt Published November 9, 2026 · [Daniel Tello](https://revelraw.com/about.md) · RevelRaw **DNG vs RAW:** In RevelRaw's November 2026 test, 16 camera RAW files converted to lossless DNG kept their raw sensor data, by the converter's own check. Most of the size saving came from a smaller preview (12.1% smaller in total, only 3.3% with previews set aside), and the DNGs lost the camera's maker notes, such as picture style and focus mode. Keep your originals; convert only for a reason. Many DNG vs RAW articles repeat that DNG is 15 to 20% smaller and "lossless". We converted real files from six camera brands and measured. Only need to open one? See [opening a DNG on your Mac](https://revelraw.com/blog/how-to-open-dng-files-on-mac.md); for the format itself, read [what a DNG file is](https://revelraw.com/blog/what-is-a-dng-file.md). Open your RAW files free on a Mac. RevelRaw · Your first full-quality export is free · macOS 26 or later · Apple M1 or later [Open RAW files free](https://apps.apple.com/app/apple-store/id6773942240?pt=120914369&ct=BlogDngVsRaw&mt=8) ## DNG vs RAW file size: 16 conversions measured Across all 16 files, the lossless DNGs came to 562.73 MB against 640.48 MB of originals, 12.1% smaller in total, but single files ran from 44.8% smaller to 92.7% larger. | Camera | Change | Format and mode | Original | Lossless DNG | | --- | --- | --- | --- | --- | | [Canon EOS R6 Mark II](https://raw.pixls.us/getfile.php/6402/nice/Canon%20-%20EOS%20R6%20Mark%20II%20-%203:2.cr3) | −9.7% | CR3 RAW (lossless) | 29.40 MB | 26.54 MB | | [Canon EOS R6 Mark II](https://raw.pixls.us/getfile.php/6409/nice/Canon%20-%20EOS%20R6%20Mark%20II%20-%203:2.cr3) | +60.0% | CR3 C-RAW (lossy) | 16.47 MB | 26.35 MB | | [Canon EOS R5 Mark II](https://raw.pixls.us/getfile.php/7881/nice/Canon%20-%20EOS%20R5%20Mark%20II%20-%20RAW%20(3:2).CR3) | −20.4% | CR3 RAW (lossless) | 54.44 MB | 43.33 MB | | [Canon EOS Rebel T7i](https://raw.pixls.us/getfile.php/4067/nice/Canon%20-%20EOS%20REBEL%20T7i%20-%20RAW%20(3:2).CR2) | −13.7% | CR2 RAW (lossless) | 29.63 MB | 25.57 MB | | [Sony a7 IV](https://raw.pixls.us/getfile.php/6928/nice/Sony%20-%20ILCE-7M4%20-%2014bit%2014bit%20uncompressed%20(3:2).ARW) | −44.8% | ARW Uncompressed | 73.46 MB | 40.54 MB | | [Sony a7 IV](https://raw.pixls.us/getfile.php/6929/nice/Sony%20-%20ILCE-7M4%20-%2014bit%20(4:3).ARW) | −22.4% | ARW Lossless compressed (L) | 49.18 MB | 38.18 MB | | [Sony a7 IV](https://raw.pixls.us/getfile.php/6932/nice/Sony%20-%20ILCE-7M4%20-%2014bit%20(3:2).ARW) | +0.4% | ARW Compressed (lossy) | 40.67 MB | 40.82 MB | | [Sony a7 V](https://raw.pixls.us/getfile.php/8845/nice/Sony%20-%20ILCE-7M5%20-%2014bit%20(4:3).ARW) | −22.0% | ARW Lossless compressed | 44.20 MB | 34.48 MB | | [Nikon Z fc](https://raw.pixls.us/getfile.php/8562/nice/Nikon%20-%20Z%20fc%20-%2014bit%20compressed%20(Lossless)%20(3:2).NEF) | −14.9% | NEF 14-bit lossless | 27.82 MB | 23.69 MB | | [Nikon Z f](https://raw.pixls.us/getfile.php/6885/nice/Nikon%20-%20Z%20f%20-%2014bit%2014bit%20compressed%20(3:2).NEF) | −15.4% | NEF 14-bit lossless | 31.11 MB | 26.31 MB | | [Nikon Z50 II](https://raw.pixls.us/getfile.php/7762/nice/Nikon%20-%20Z50_2%20-%208bit%20compressed%20(3:2).NEF) | −17.1% | NEF lossless | 27.50 MB | 22.80 MB | | [Nikon Z50 II](https://raw.pixls.us/getfile.php/7764/nice/Nikon%20-%20Z50_2%20-%208bit%20compressed%20(3:2).NEF) | n/a | NEF High Efficiency | 12.44 MB | Failed | | [Fujifilm X-T5](https://raw.pixls.us/getfile.php/6124/nice/Fujifilm%20-%20X-T5%20-%2014bit%2014bit%20uncompressed%20(3:2).RAF) | −38.4% | RAF Uncompressed | 85.71 MB | 52.78 MB | | [Fujifilm X-T5](https://raw.pixls.us/getfile.php/6122/nice/Fujifilm%20-%20X-T5%20-%2014bit%2014bit%20compressed%20(3:2).RAF) | +24.5% | RAF Lossless compressed | 43.11 MB | 53.67 MB | | [Fujifilm X-T5](https://raw.pixls.us/getfile.php/6123/nice/Fujifilm%20-%20X-T5%20-%2014bit%2014bit%20compressed%20(3:2).RAF) | +92.7% | RAF Compressed (lossy) | 28.04 MB | 54.02 MB | | [OM System OM-1 Mark II](https://raw.pixls.us/getfile.php/7262/nice/OM%20System%20-%20OM-1%20Mark%20II%20-%2016bit%20(4:3).orf) | +1.2% | ORF 12-bit | 22.44 MB | 22.71 MB | | [Panasonic Lumix S5II](https://raw.pixls.us/getfile.php/7790/nice/Panasonic%20-%20DC-S5M2%20-%2014bit%20(3:2).RW2) | −17.1% | RW2 14-bit | 37.31 MB | 30.94 MB | MB is 1,000,000 bytes. "Lossless DNG" is dnglab 0.8.0 with `--embed-raw false`; dnglab's default, which stores the whole original inside the DNG, is covered below. The raw sensor data matched in all 16 pairs. Each camera name links to the CC0 source file. Method in brief: 17 public-domain camera files from raw.pixls.us, tested on November 9, 2026 on macOS 27.0.1 with dnglab 0.8.0; one wouldn't convert. [How we tested](https://revelraw.com/blog/dng-vs-raw.md#method). ### Why some DNGs get smaller and some get bigger The DNG's size barely depends on how the camera packed the file: the three Fujifilm X-T5 files became DNGs of 52.78 to 54.02 MB whether the original was uncompressed, lossless or lossy, and the three Sony a7 IV files 38.18 to 40.82 MB. So the original decides the percentage: - **Uncompressed originals shrink the most:** Sony a7 IV 44.8%, Fujifilm X-T5 38.4%. They store every value at full size with no packing. - **Lossless-compressed originals mostly shrink a little:** 9.7% to 22.4% for Canon, Sony, Nikon and Panasonic. The Fujifilm X-T5 lossless file grew 24.5% and the OM-1 Mark II 1.2%; there the camera's own packing beat dnglab's single lossless method, lossless JPEG. - **Lossy originals grow:** Canon C-RAW 60.0%, Fujifilm Compressed 92.7%, Sony Compressed 0.4%. The camera saved space by discarding precision; a lossless DNG stores the decoded values in full. **Most of the saving is the preview.** Originals carry the camera's own JPEG preview, often full size, and the DNG swaps it for a small one. Take each original's largest preview out of the count and the 16 DNGs come to 3.3% smaller in total, not 12.1%, and the Canon R6 Mark II's RAW goes from 9.7% smaller to 4.7% larger. The smaller DNG mostly comes from the smaller preview, not from tighter packing of the sensor data. To save space going forward, change the camera setting instead: lossless compressed beats uncompressed with no conversion, as our [test of every Sony RAW compression mode](https://revelraw.com/blog/sony-compressed-vs-uncompressed-raw.md) and the [RAW file size study](https://revelraw.com/blog/how-big-is-a-raw-file.md) show. And skip uncompressed DNG: on the four files we tried, it came out 49.9% to 90.2% larger than the original. ### dnglab's default doubles up: the original goes inside Run dnglab with no options and it embeds the whole original RAW in the DNG, its documented default. Every default DNG was 32.9% to 190.6% larger than its original, 80.4% more in total (640.48 MB became 1,155.55 MB). The upside: the original came back out of all 16 byte for byte. The command for a DNG on its own is in [how to convert](https://revelraw.com/blog/dng-vs-raw.md#convert). Dropping the preview and thumbnail too saved only 0.18 to 0.32 MB more (four files). Conversion takes about 0.2 seconds per file on this Mac with the original left out, about 0.3 seconds with it. ## Does converting RAW to DNG lose quality? Not the sensor data, in our test. dnglab can take a fingerprint of the raw sensor values alone, ignoring previews and metadata; change a single value and the fingerprint changes. The DNG's raw data matched the original as dnglab reads it: 40 of 40 fingerprints, across 16 originals and four settings. A second free RAW reader agreed on 12 of the 16 pairs. On the other four, the three Nikon NEFs (about 75% of values off by exactly 1) and the lossy Sony a7 IV ARW (off by up to 8), we compared dnglab and the second reader on the original files alone, with no DNG involved, and they disagreed in the same way. The Nikon differences are spread evenly through the frame. On a lossless Sony a7 IV file, our control, the two agreed on every value. So the two programs read those four originals slightly differently, and the DNG holds exactly what dnglab reads. Which reader is right we can't say; the difference exists before any conversion. One caveat: Canon C-RAW, Sony Compressed and Fujifilm Compressed discard some data in the camera, and converting can't bring it back. "Identical" there means no further loss. ## What a DNG conversion drops: maker notes, picture style, focus data dnglab kept the standard exposure data and dropped the maker notes. Cameras write two layers of information: standard EXIF that any app reads, and maker notes, a private block for everything else. ExifTool counted 85 to 449 maker-note tags per original and none in the 16 DNGs made with the original left out; all tags together fell from 191–561 per file to 72–83. In dnglab's default DNGs the maker notes survive inside the embedded original, but the DNG doesn't show them to other apps. | Information | Kept in the dnglab DNG | | --- | --- | | Shutter speed, aperture, ISO, capture time, orientation | 16 of 16 files, unchanged | | Camera make and model, lens name | 16 of 16, but often reworded: the make in 10 files, the model in 8, the lens name in 9 ("Canon EOS R6m2" became "EOS R6 Mark II") | | Artist or copyright | 9 of the 9 files that had it | | White balance setting | 15 of 16 (lost on the Panasonic; the Nikon Z fc's "Sunny" came out as "Manual") | | Camera serial number | 12 of 16 (lost on two bodies: the three Sony a7 IV files and the OM-1 Mark II) | | Lens serial number | 9 of the 11 files that had it (two of those are Canon's placeholder, 0000000000) | | Picture Style, Picture Control, Creative Style, Film Simulation | 0 of 16 | | Focus mode | 0 of 16 | | AF area mode | 0 of the 15 files that had it | | GPS location | Not tested: none of the originals had it | What's lost describes how the camera's own JPEG looked and how the camera focused. Check your own files before and after with our [free EXIF viewer](https://revelraw.com/exif-viewer.md). **Previews shrink too.** Every DNG got a 1024-pixel-wide preview (about 43 to 311 KB) and a thumbnail (180 × 120; 160 × 120 on the OM-1 Mark II); the four test DNGs made with both switched off carry neither. The originals carried previews up to full size, such as 7008 × 4672 on the Sony a7 IV. In an app that shows embedded previews, you'll see a small image instead of the camera's JPEG. For the Canon R5 Mark II and OM-1 Mark II, dnglab found no usable preview and made its own. ## Why your Mac shows the DNG differently from the RAW Open an original and its DNG side by side on a Mac and they may not match. We had macOS render every pair with its built-in RAW support. Across the 13 pairs that aren't Fujifilm, brightness moved both ways, from about 20 levels darker (Nikon Z50 II) to about 22 brighter (Nikon Z fc) on a 0 to 255 scale, and barely at all on others, such as the OM-1 Mark II. Colors shifted too, and by eye the Canon R6 Mark II and OM-1 Mark II DNGs were framed differently. Separately, none of the DNGs carry lens-correction instructions (0 of 16), so in-camera lens corrections didn't come along. The raw data matched in every pair: what changed is how the Mac shows the file, not what it holds. ![Rooftops with solar panels: natural color from the original RAF on the left, a heavy magenta cast from the converted DNG on the right.](https://revelraw.com/images/dng-vs-raw-xtrans-magenta-1600.jpg) *Fujifilm X-T5 lossless RAF (left) and its dnglab 0.8.0 DNG (right), both rendered by macOS 27.0.1 itself. Photo: CC0 from raw.pixls.us.* **macOS shows dnglab's X-Trans DNGs magenta.** All three Fujifilm X-T5 DNGs rendered magenta when macOS opened them. Quick Look showed them magenta too, except dnglab's default DNGs, where it showed the normal-looking embedded preview. On the lossless file, average brightness fell from 105.3 to 75.8 and green dropped to about half. The second reader didn't render the two we tried properly either. The raw data matches, and a recheck found the DNG's 6 × 6 X-Trans color-pattern tags agree with the RAF's on every pixel of the image, so we can't say where the fault lies. We tested only dnglab's DNGs, on macOS 27.0.1 and one other free RAW reader. dnglab's own issue tracker has an open report ([issue #525](https://github.com/dnglab/dnglab/issues/525), March 2025) of X-Trans DNGs from an earlier dnglab version showing red in RawTherapee. **What it means for you:** a conversion that checks out on paper can still look wrong in the app you use. If you shoot X-Trans, open converted files in the app you'll actually use before deleting any original; with any camera, compare a handful of converted files with their originals first. Open your RAW files on this Mac in the next minute. RevelRaw reads RAW straight from Finder, no plug-ins or converters. Your first full-quality JPEG export is free. macOS 26 or later · Apple M1 or later [Open RAW files free](https://apps.apple.com/app/apple-store/id6773942240?pt=120914369&ct=BlogDngVsRaw&mt=8) ## Should you convert RAW to DNG? A verdict for each situation - **You edit on a Mac and your apps open your RAW files:** don't convert. You gain no quality and lose maker metadata. - **You shoot Canon C-RAW, Fujifilm Compressed or another lossy mode:** don't convert to save space. Those files grew by up to 92.7% in our test. - **You shoot Nikon High Efficiency:** dnglab 0.8.0 can't convert it; keep the NEF. - **You shoot uncompressed and need space:** converting saves the most here, but switching the camera to lossless compression saves space without converting. - **An older app can't read your new camera's files:** Adobe says its converter provides "backwards compatibility for the latest cameras for use in older versions" of its apps. Convert copies and keep the originals. - **You rely on Canon DPP, Nikon NX Studio, Sony Imaging Edge or Fujifilm X RAW Studio:** keep native RAW. - **You shoot Fujifilm X-Trans and planned to use dnglab:** check converted files in the app you'll actually use first; macOS 27.0.1 showed dnglab 0.8.0's X-Trans DNGs magenta. - **You want an archive copy in a published format:** a DNG alongside the original is reasonable. Delete the original only if you've embedded it in the DNG and checked that you can get it back. When a RAW file won't open, the cause is often something other than the format: [find out why your Mac can't open a RAW file](https://revelraw.com/blog/raw-files-wont-open-on-mac.md) before reaching for a converter. ### How to convert RAW to DNG on a Mac (and keep the original) We didn't test these two Adobe routes in our lab; the steps come from Adobe's help pages. - **Adobe DNG Converter** is a free Mac app. In [Adobe's steps](https://helpx.adobe.com/camera-raw/desktop/dng-and-file-formats/adobe-dng-converter.html), you select the folder of images to convert, select where to save the DNGs, pick a naming pattern and click Convert; Change Preferences holds the compatibility settings. It writes new files to the place you chose, so keep the originals where they are. Adobe says the original can also be embedded in the DNG "to ensure that proprietary metadata from the manufacturer is not lost". - **Lightroom Classic** can convert as you import: at the top of the import window, choose [Copy As DNG](https://helpx.adobe.com/lightroom-classic/help/import-photos-video-catalog.html), which "copies photos to the folder you choose and converts any camera raw files" to DNG. Keep the card, or another copy of the originals, until you've checked the DNGs. One point in DNG's favor if you edit in Adobe's apps: Adobe's [DNG vs RAW page](https://www.adobe.com/creativecloud/file-types/image/comparison/dng-vs-raw.html) says that with DNGs, "edits and changes are written directly into the file", while a native RAW keeps them in a separate .xmp sidecar file beside it. If you're comfortable in Terminal, dnglab is the converter we tested: `dnglab convert --embed-raw false photo.ARW photo.dng` `--embed-raw false` leaves the original out, so you get the DNG on its own. Without it, dnglab puts the whole original inside the DNG, which made our files 80.4% larger in total but lets you get the RAW back. ## DNG vs NEF: what Nikon shooters should know Keep the NEF. Converting saves a little space and drops Nikon's own data. The three lossless NEFs, from the Nikon Z fc, Z f and Z50 II, became DNGs 14.9% to 17.1% smaller with matching raw data by dnglab's fingerprint (the off-by-1 values above are a reader disagreement about the NEF itself). Each lost its maker notes and Picture Control setting. The Z50 II's High Efficiency NEF didn't convert: dnglab 0.8.0 stopped with "NEF compression Some(HighEfficency) is not supported", and its camera list shows the Z50 II under 14-bit only. Nikon's own software is the other catch: [NX Studio's supported-format list](https://nikonimglib.com/nxstdo/onlinehelp/en/supported_formats_4.html) names "RAW pictures in NEF and NRW formats", not DNG. If a NEF won't open on your Mac, our guide to [opening NEF files on a Mac](https://revelraw.com/blog/how-to-open-nef-files-on-mac.md) is a better first stop than converting. ## DNG vs CR3, ARW and RAF: what changed by brand Most CR3 and ARW files shrank a little and uncompressed ones the most; Canon C-RAW and every Fujifilm RAF except Uncompressed grew, and each maker's own software is built around its own format, not DNG. **Canon CR3 and CR2.** Full RAW CR3s shrank (the R6 Mark II's 9.7% is all preview), and so did the T7i's CR2. C-RAW is the trap: a 16.47 MB C-RAW became a 26.35 MB DNG. [Canon's Digital Photo Professional](https://cam.start.canon/en/S002/manual/html/UG-00_Before_0060.html) lists ".CR3 .CR2 .TIF .CRW .CIP .CRN" as its RAW formats; DNG isn't there. **Sony ARW.** Uncompressed shrank most and Compressed stayed level. Lloyd Chambers [reported in 2022](https://diglloyd.com/blog/2022/20221215_0830-SonyA7R_V-AdobeDNGConverter-SonyWorkflowTax.html) that "the Sony software doesn't work with DNG", and Sony keeps building on its own software: Imaging Edge Desktop's [May 2026 update](https://support.d-imaging.sony.co.jp/app/imagingedge/en/) added Pixel Shift Multi Shooting synthesis for the ILCE-7RM6. **Fujifilm RAF.** Only Uncompressed shrank, before counting the magenta rendering. Fujifilm's [X RAW Studio](https://fujifilm-x.com/global/products/software/x-raw-studio/) processes RAF files with the camera itself, so it's built around the original RAF. ## How we tested: 17 files in, 16 DNGs out **Converter scope.** We tested [dnglab 0.8.0](https://github.com/dnglab/dnglab/releases/tag/v0.8.0), a free, open-source converter run from Terminal, which its makers still call "alpha state". We did not test Adobe DNG Converter. Every measured number here is dnglab output; Adobe's own statements are quoted in [the background section](https://revelraw.com/blog/dng-vs-raw.md#background). **Setup.** On November 9, 2026, on an Apple M5 Pro Mac running macOS 27.0.1, we took 17 public-domain (CC0) RAW files from 11 camera bodies in the [raw.pixls.us](https://raw.pixls.us/) archive, linked in the table; all matched the archive's own file fingerprints. They cover Canon CR3 and CR2, Sony ARW, Nikon NEF, Fujifilm RAF, OM System ORF and Panasonic RW2, in several compression modes. We converted each three times, with dnglab's default and with the original left out, and compared sizes, raw sensor values (dnglab's fingerprint, plus LibRaw 0.22, a second free, open-source RAW reader), metadata (ExifTool 13.55), previews, and how macOS and Quick Look show each file. A Nikon High Efficiency NEF wouldn't convert, leaving 16 pairs. ## DNG background: the standard, cameras that shoot it, Adobe's converter DNG (Digital Negative) is a raw format Adobe introduced in 2004. Its specification, version 1.7.1.0 from September 2023, is a free download under a [royalty-free patent license](https://helpx.adobe.com/camera-raw/desktop/dng-and-file-formats/digital-negative.html) with conditions: openly published, not open source. Since March 2026 it is also [ISO 12234-4:2026](https://www.iso.org/standard/86123.html). Some cameras write DNG themselves. The [Leica M11](https://leica-camera.com/en-US/photography/cameras/m/m11-black/technical-specification) records "DNG™ (raw data, loss-free compression)", the [Pentax K-3 Mark III](https://www.ricoh-imaging.co.jp/english/products/k-3-3/spec/) offers PEF or DNG, the [Ricoh GR IV](https://www.ricoh-imaging.co.jp/english/products/gr-4/spec/) writes "RAW (DNG) 14bit", and [Apple says](https://support.apple.com/en-us/119916) iPhone ProRAW "uses the industry standard digital negative (DNG) file format". Adobe's comparison page also names Hasselblad, but Hasselblad's X2D writes 3FR, not DNG. If your camera writes DNG, there's nothing to convert. On archiving, Adobe's [DNG vs RAW page](https://www.adobe.com/creativecloud/file-types/image/comparison/dng-vs-raw.html) says "the United States Library of Congress uses DNG files for this purpose". The Library's [format description](https://www.loc.gov/preservation/digital/formats/fdd/fdd000188.shtml) lists DNG as "an acceptable format for photographs", with "LC preference: None established". **Adobe DNG Converter (we didn't test it).** Adobe's free converter is at version 18.7 (September 2026), needs ["macOS Ventura (version 13) or later"](https://helpx.adobe.com/camera-raw/desktop/dng-and-file-formats/adobe-dng-converter.html), and, Adobe says, "converts files from more than 600 cameras to DNG". The rest is Adobe's description, not our measurement: - **Lossless is the default.** The command-line guide lists "Output lossless compressed DNG files (default)", an option to "Embed original raw file inside DNG files", and lossless and lossy JPEG XL. Lossy DNGs are a different trade from anything we tested. - **Linear DNG is one-way.** The converter can store the image already turned into full-color pixels, a "linear" DNG, and Adobe's help says that can't be turned back into the raw form. - **Metadata may not all survive.** The converter "may, in some cases, ignore some of this proprietary metadata", Adobe's help says, suggesting you embed the original so it "is not lost". A reply [Lloyd Chambers published in 2022](https://diglloyd.com/blog/2022/20221215_0830-SonyA7R_V-AdobeDNGConverter-SonyWorkflowTax.html), written in the converter maker's voice, says Adobe includes "Canon, Nikon, and Sony MakerNote data when converting from CR2/CR3/NEF/ARW/ARQ to DNG", but adds: "we deliberately exclude the private MakerNotes from lossy-compressed DNGs". So Adobe's lossless output may keep maker data that dnglab's dropped; we haven't measured it. Adobe's page also says DNGs are "generally 15-20% smaller than RAW files", without a test. Our dnglab results ran from 44.8% smaller to 92.7% larger, but a different converter isn't a direct test of Adobe's figure. You don't need DNG to edit on a Mac. RevelRaw, the Mac RAW editor we make, opens 24 RAW formats directly, CR3, NEF, ARW, RAF and DNG among them, so you can edit the file your camera wrote. We didn't run RevelRaw on this test's DNGs. Editing is free, your first full-quality export is free, and Pro adds unlimited exports and batch export. The full list is on the [formats page](https://revelraw.com/formats.md). Open your RAW files on this Mac in the next minute. RevelRaw reads RAW straight from Finder, no plug-ins or converters. Your first full-quality JPEG export is free. macOS 26 or later · Apple M1 or later [Open RAW files free](https://apps.apple.com/app/apple-store/id6773942240?pt=120914369&ct=BlogDngVsRaw&mt=8) ## FAQ ### Is DNG better than RAW? Not for image quality when the DNG is lossless: in RevelRaw's November 2026 test of 16 camera files converted with dnglab 0.8.0, the DNG's raw data matched the original as the converter decodes it in every file. DNG is an openly published ISO standard; native RAW keeps all the maker's metadata and works in the camera maker's own software. Keep the original unless you have a reason to convert. ### Does converting to DNG lose quality? Lossless conversion didn't change the raw data in our test: dnglab's fingerprint of the raw sensor values matched in 40 of 40 DNGs made from 16 originals. What you can lose is information. Maker notes, including the picture style or film simulation and the focus mode, were gone from all 16 DNGs made without the original embedded. Lossy DNG options in Adobe's converter are a different trade. ### Is DNG smaller than RAW? Sometimes. In our test lossless DNGs ranged from 44.8% smaller (an uncompressed Sony ARW) to 92.7% larger (a Fujifilm compressed RAF), and 12.1% smaller across all 16 files, mostly because the DNG carries a smaller preview: without previews the saving was 3.3%. Lossy originals such as Canon C-RAW grow. With the original embedded, dnglab's default, every DNG was larger. ### DNG vs NEF: which should Nikon shooters keep? The NEF, for most people. Lossless NEFs from the Nikon Z fc, Z f and Z50 II became DNGs 14.9% to 17.1% smaller with matching raw data by dnglab's fingerprint, but lost their maker notes and Picture Control setting. dnglab 0.8.0 couldn't convert a High Efficiency NEF, and [Nikon NX Studio's format list](https://nikonimglib.com/nxstdo/onlinehelp/en/supported_formats_4.html) doesn't include DNG. ### Should I delete my raw files after converting to DNG? No. Conversion drops the maker notes, and in our test the Mac showed some DNGs differently from their originals, including Fujifilm X-T5 DNGs in magenta. Keep the originals, or embed them in the DNG and check you can get them back, and test converted files in the app you'll actually use first. ### Can you convert a DNG back to RAW? Only if the original is inside it. dnglab's default embeds the original RAW file, and in RevelRaw's November 2026 test all 16 came back out byte for byte. A DNG made without the original can't be turned back into the camera's file. ### Can my Mac open DNG files? Yes. [macOS has built-in DNG support](https://support.apple.com/en-us/127493), so Preview, Photos and Quick Look open most DNGs; in our test Quick Look made a thumbnail for all 40 dnglab DNGs, though the Fujifilm X-T5 ones made without the embedded original were magenta. RevelRaw opens DNG and native RAW files directly, so you don't need to convert to edit. Related reading: [What is a DNG file?](https://revelraw.com/blog/what-is-a-dng-file.md) · [Open DNG files on a Mac](https://revelraw.com/blog/how-to-open-dng-files-on-mac.md) · [How big is a RAW file?](https://revelraw.com/blog/how-big-is-a-raw-file.md) · [NEF](https://revelraw.com/blog/what-is-a-nef-file.md) · [CR3](https://revelraw.com/blog/what-is-a-cr3-file.md) · [ARW](https://revelraw.com/blog/what-is-an-arw-file.md)