Raw File Size

[leosantare]

Hello,

I'm just trying to get a good idea of the space I will need for my picture collection. This way, I can choose an appropriate size hard drive. I'm looking to get a new camera and plan to shoot exclusivley in the largest raw format option. Let's take the Cannon EOS Ra for example or any other 30 megapixel camera. That should be around 6720 x 4480 and the raw file size being about 50MB per image. Is this correct?

My main question is what else is involved. For example, I will have to convert all my raw files to DNG so I can edit them in older camera raw software. At that point, I would delete the origial raw file. What would a DNG file size be when converting it from a 30mp raw file?

Now, I have just a DNG file. In order for me to edit or view this picture, will I need a copy of the image in another format, such as Tiff? Basically, will I end up with 2 copies for each picture, a DNG and a Tiff? I guess I could edit the DNG, save it as a Tiff and then delete the DNG file.

Once I know about how much space I need for one picture, I can then detrmine how much space I need for my collection.

Thank you,   

[Per Berntsen]

Raw files are compressed, and file size will vary with image content.

Lots of sharp, busy detail (and noise) does not compress well, and will lead to a larger file size, and predominantly flat, smooth areas do compress well, and will lead to a smaller file size.

I found a collection of sample files for the 30 MP Canon EOS R, and the file size varied between 27 and 48 MB.

I downloaded a 40.6 MB file, from which I made two conversions to DNG – one with a medium size embedded jpg preview (1024 pixels on the long side), and one with a full size preview.

They came out at respectively 37.4 and 46.6 MB. The image happened to be very noisy, which explains the large size of the full size preview (image content has a large influence on jpg file size).

I routinely convert all my raw files to DNG, and use the medium size preview, which saves some space.

I usually delete the original raw files soon after the conversion, but not until the DNGs have been backed up.

As an additional precaution, I have set Lightroom Classic to automatically write changes into XMP, which saves the edits to the header of the DNG files, with no need for sidecar XMP files, as with proprietary raw files. (you can probably do the same thing in Bridge/Camera Raw)

I also don't format camera cards until I have to, which works as an extra, temporary backup.

You don't have to create Tiff (or jpg) copies of every DNG file.

If you need a copy for a particular purpose, export from Bridge. If you don't need a copy, don't export.

Never delete raw files (unless they are rejected).

They are like film negatives, containing large amounts of information that is not immediately visible until you make a print.

A raw file is a hundred times more worth than a tiff, and a thousand times more worth than a jpg.

You will get much better and higher quality results from editing a raw file than from editing a tiff.

And although you may be pleased with the way you have edited an image, as your skills improve, it is likely that you'll want to edit it again at a later stage. I've been working with raw files for almost 20 years, and I often re-edit older work, also because Camera Raw (or Lightroom Classic, which I use) is getting new features that makes is possible to do things I couldn't do previously.

[TheDigitalDog]

Generally, DNG converted raws take up less space than proprietary raws. There are other advantages and a few disadvantages of DNG but for me, everything gets converted.

As to keeping the proprietary raws, that's up to you. Some suggest always save them. Some suggest a DNG (which is as raw as the original) is fine and being openly documented like TIFF, is fine for future access. If you ever decide you'd go back to the camera makers proprietary software, then yeah, keep the proprietary raws. I have zero intention of ever doing so. You can embed the proprietary raws into the DNG, seems pointless to me but that's yet another option. Consider TIFF (and JPEG) as an output specific format. You need a JPEG to upload to say the web, and it has to be sized so you'll render the DNG/raw to the size, color space and format needed. The same may be true for TIFF if you send the image out for printing. Or you want to work in Photoshop from the rendered raw. At this point, you've got a new version in TIFF and of course, you want to keep that too.

[leosantare]

Okay, so for 30MP proprietary raw files, I should fiqure about 50MB each.

When I convert the proprietary raw file to DNG, do I have to include a preview? I thought when converting a proprietary raw file to DNG you end up with a slightly smaller file. Either way, I need to know what a 50MB proprietary raw file becomes in size when converted to DNG. I will be deleting my proprietary raw files once converted to DNG.

I only plan to use Photoshop (13.0.1) and Carema Raw (9.1.1) for my pictures. 

Can I open/edit a DNG file in Camera Raw and save it as a DNG? 

(Meaning, save the DNG file as a DNG by overwriting the current DNG file. This way, I don't end up with (2) DNG files for the same picture.)

I guess this isn't recommended, the original DNG file should remain as is and backed up. Since you can't really do anything with a DNG file, (other than view/edit it in Camera Raw) should I edit and save it as a TIFF or JPEG? (I personally would be going with TIFF.) 

If this is the case, I will end up with (2) copies for each picture, (one DNG and one TIFF.) How much space will a TIFF file be coming from a DNG that was 30MP?

Thank you,

[TheDigitalDog]

The DNG will work in ACR/LR just like the proprietary raw, with respect to previews and parametric edits. No, you don't need any more than the one DNG and after getting, the instructions (depending on the product and settings) are simply instructions to render a new image as a TIFF, JPEG, PSD etc. Yes you want to backup the DNG and other settings. And again, if you render the DNG as a TIFF then edit that TIFF, you'd want to backup both. They are no longer the same.

You might want to view at least these two pieces on DNG to get a better idea of what it provides:

http://digitaldog.net/files/ThePowerofDNG.pdf

https://www.cnet.com/news/adobe-offering-new-reasons-to-get-dng-religion/

As for space: HDs are inexpensive and your images are valuable. Get the biggest drive you can afford, understand that in the future, prices will continue to drop, they drives will get bigger and you'll be making more images. It isn't a big deal, it is expected that you may need to copy your assists from one driver to another bigger drive in the future.

[leosantare]

This was about file size. I'm not just giong to get the largest hard drive I can afford. I want to know beforehand. 

It would be a lot easier for me to find out myself. Can anyone proivide me a 30-40MP raw file? I will convert it to DNG and then make a TIFF/JPEG copy. At that point, I will know what I need. 

Also, for someone who takes pictures as a hobby, what would be an average size library, 500, 1000, 2500, 5000 pictures? That might be a hard question to answer. I'm just thinking, realistically how many pictures I would want to have and what is about average for hobbist.

[TheDigitalDog]

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@leosantare wrote:

I want to know beforehand. 

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You do realize that a 16-bit TIFF is twice the size on disk as the 8-bit version and both increase in size depending on how many layers and what is on the layer(s) you may make in Photoshop? IOW, it's impossible to answer the question based just on those attributes of a rendered image.

[leosantare]

Can anyone provide me a 30-40 MP raw image?

Thank you,

[Per Berntsen]

This is where I downloaded a sample file, after doing a Google search for "canon eos r sample images raw"

I couldn't find any sample raws for the EOS RA.

https://drive.google.com/drive/folders/1-ZoYTZlIOqkNJSXUrGPES_OWEBinD_cq

[TheDigitalDog]

Go to DP Review and download one or more (and yes, they will all vary somewhat in size depending on a number of factors including your OS and HD are) AND compression, type of raw, and more. 

[Per Berntsen]

When I convert the proprietary raw file to DNG, do I have to include a preview? I thought when converting a proprietary raw file to DNG you end up with a slightly smaller file.

You don't have to include a preview.

The preview is only used by applications that cannot render the DNG file.

But medium size previews add very little to the file size.

DNG files will not always be smaller than the original raw files.

I have found that creating DNGs from Nikon NEF files result in roughly 15% smaller files.

With RAF files from my Fuji GFX camera, there is very little difference, sometimes the DNGs are slightly larger.

I'm shooting compressed raw with both cameras, and if I had shot uncompressed raw, there would have been a substantial difference in file size.

[leosantare]

I went to DP review and found a 51.1MB .NEF raw file. I wanted to test that since I was told that 30MP proprietary raw files are about 50MB each, on average. If this is incorrect, please let me know.

I converted the NEF to DNG without a preview, without embed fast load data, without use lossy compression and without embed original raw file. I ended up with a 42.7MB DNG file.

Next, I opened the DNG in Camera Raw and saved it a JPEG with (12) maximum quiality and ended up 16.5MB. I also saved the DNG as a TIFF and it became a crazy 130MB!

If that is the case, I will be definetley saving my DNG's as JPEG's. With 42.7MB for the DNG's and 16.5MB for the JPEG's, I should figure about 59.2, or 60MB for each picture. Is this pretty accurate?

Now, you do have some Color Space options in Camera Raw and assume these would change the size of the JPEG and TIFF files. I had them set to Adobe RGB 1998 and 8Bits/Channel. I assume these are the default settings and what most people use. Any reason why I would want to change these Color Space settings in Camera Raw?

Thank you,

[TheDigitalDog]

If that is the case, I will be definetley saving my DNG's as JPEG's

By @leosantare

You can't save your DNGS AS JPEGs, You can render the raw and save that rendering as a JPEG. The JPEGs are no longer raw (the DNGs are).So you have a JPEG and a DNG. And you'll want to keep both, but certainly the DNG; you'd never throw it away in exchange for a DNG.

Would you make an 8x10 print then throw away the original film?

They are only 8-bit per color now.

You've thrown away a HUGE amount of data!

Ideally you want to stick with the raw data. And your DNGs! The JPEG engine that processes the raw

massively clips and compresses highlights. We often don't when editing the raw. This compression can clump midtones as much as 1 stop while compressing shadow details! People incorrectly state that raw has more highlight data but the fact is, the DR captured is an attribute of the capture system; it's all there in the raw but maybe not in a camera proceed JPEG.

A raw capture that's 10 or 11 stops of dynamic range can be compressed to 7 stops from this JPEG processing which is a significant amount of data and tonal loss! So when we hear people state that a raw has more DR than a JPEG, it's due to the poor rendering or handling of the data to create that JPEG. The rendering of this data and the reduction of dynamic range is from the JPEG engine that isn't handling the DR data that does exists as well as we can from the raw! Another reason to capture and render the raw data, assuming you care about how the image is rendered!

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I had them set to Adobe RGB 1998 and 8Bits/Channel. I assume these are the default settings and what most people use.

No. And you can't replicate the original color space of this raw data.

[leosantare]

Should I figure about 75mb for each picture, with a 30mp camera?

(50mb for the dng and 25mb for the jpeg)

Therefore, a 1000 picture libary would be about 75gb, is this correct?

[Per Berntsen]

As I explained in my first post, the size of a raw file depends to some degree on image content, so the file size of a 30 MP image will vary considerably. But they will be closer to 30 MB than 50 MB on average.

A 30 MP (6720 x 4480) 8-bit Tiff will be 86.1 MB. This is perfectly normal for an uncompressed file. Raw files as well as jpg files are compressed. The tiff format also offers lossless compression, LZW compression for 8-bit files can be very effective.

ZIP compression works best for 16-bit files.

For jpg files, image content has an even greater influence on file size than for raw files.

Consider the image below, a 50 MP image exported at full size, 100 quality, in three versions.

The blurred version is significantly smaller than the original, and the noisy version is considerably larger than the original.

To get a better understanding of how digital images and various file formats work, you may find these articles helpful.

What is a digital image?

File formats 

Original, 43.7 MB

Blurred, 11.5 MB

Noisy, 90.2 MB

[Conrad_C]

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@leosantare wrote:

I went to DP review and found a 51.1MB .NEF raw file. I wanted to test that since I was told that 30MP proprietary raw files are about 50MB each, on average. If this is incorrect, please let me know.

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It’s just not easily predictable. The size of a proprietary raw file can vary greatly depending on factors such as:

• What method do they use to store the data? Different camera makers use different methods, and being proprietary, format documentation is often not provided to anyone outside the company. 
• At what bit depth was the data recorded? Of course, that can vary depending on the camera model.
• Does that camera maker apply compression to their raw files? Some apply no compression, some apply lossless, some apply lossy but only enough that you can’t see the difference. 

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@leosantare wrote:

Next, I opened the DNG in Camera Raw and saved it a JPEG with (12) maximum quiality and ended up 16.5MB. I also saved the DNG as a TIFF and it became a crazy 130MB!

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Not crazy. The TIFF size is the natural file size of the image. To calculate file size of a normal RGB image, not specific to any software, you multiply:

number of pixels * bits per pixel * channels

If you do that for the pixel dimensions of your image, it should be in the range of 130MB. Totally normal.

JPEG is smaller because so much original data has been thrown out. Raw is smaller because it’s just a one-channel raw stream and not yet a demosaiced three-channel RGB image, but in that form, a raw file is not immediately usable by most software, which expect a standard RGB image. So while it is nice that JPEG and raw are much smaller files, that only comes with serious compromises in both cases. The TIFF image has the fewest compromises (the most usefulness) in terms of editability and wide compatibility, but the biggest compromise for it is large file size. If I need TIFF, I always apply one of the lossless compression options to reduce the file size somewhat.

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@leosantare wrote:

Now, you do have some Color Space options in Camera Raw and assume these would change the size of the JPEG and TIFF files. I had them set to Adobe RGB 1998 and 8Bits/Channel. I assume these are the default settings and what most people use. Any reason why I would want to change these Color Space settings in Camera Raw?

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The options in the Workflow preferences affect the conversion from Camera Raw directly to Photoshop (e.g., the Open button at the bottom of the Camera Raw window). If you are not going directly from Camera Raw to Photoshop, they (mostly) don’t apply. For example, if you are saving JPEG or TIFF files directly from Camera Raw to a hard drive, you will be going through the Save Options dialog box, so the Workflow Options won’t apply. In this example, you must set Color Space and Bit Depth correctly in the Save Options dialog box.

Color Space probably doesn’t affect file size significantly, but it can affect how much of your image’s original color range is preserved in the JPEG or TIFF. For example, if you want to take full advantage of the range of colors of a pro photo inkjet printer, sRGB is not big enough.

Bit Depth will affect the file size; an image is generally twice the file size at 16 bits per channel files than at 8 bits per channel. But if you are using a larger color space such as ProPhoto RGB (some would say Adobe RGB or P3 as well), you should also be choosing 16 bpc so that each channel has enough levels to reproduce more colors smoothly (without banding).

[floramc]

I am slightly off topic but I wanted to say that I enjoyed reading your post. Personally I never got routined to convert my raws. I work on a D750 (Nikon) and my raw files are not that invasive in termed of space. 

I would never delete my RAW as dngs are neglected outside of the Adobe environment, more or less, hence instead of saving space, I would clutter my hard disks. This is why I am slightly off topic. 

Nontheless I found reading your reply very interesting: your no intentions in relation to raw is a new for me. I do not want to carry this message off topic, I just wanted to say I found this post somewhat revealing and thank you for that.

[TheDigitalDog]

I would never delete my RAW as dngs are neglected outside of the Adobe environment....

By @floramc

I have no less than three very good raw converters that are not an Adobe product that fully support DNG. And there are more than just those. Like it's cousin TIFF, any software that wishes to support DNG can do so for no cost; it is an openly documented file format.

[Lumigraphics]

There isn't a way to pre-determine how much drive space you need. As everyone is telling you, file sizes will vary depending on numerous factors.

Right now, you can get a 4-6TB hard drive for under $US100. Storage prices will continue to fall, by the time you are close to filling one drive, a second one will be larger and cheaper.

[leosantare]

Thanks everyone. I insist there be a way to predetermine how much space my picture library will be. Atleast to some degree. Again, I'm not looking for a exact amount, just a calculated idea.

You said, 30mb is more of an average for 30mp raw files, instead of 50mb. Are you referring to the proprietary raw files or the converted dng files?

After I convert to dng, I plan to open in camera raw, make adjustments if needed and then render as jpeg or tiff. Although, I'm undecided as to which one right now. 

Plus, I'm undecided on which camera raw workflow options to go with. It looks like 16bit is best and/or more common.

After spending time processing/correcting the raw(dng) file and rendering it to a jpeg or tiff, why keep the dng? 

I may process the dng and render in both tiff and jpeg. Then, discard the dng.

[elie_dinur]

"After I convert to dng, I plan to open in camera raw, make adjustments if needed and then render as jpeg or tiff. Although, I'm undecided as to which one right now.

Plus, I'm undecided on which camera raw workflow options to go with. It looks like 16bit is best and/or more common.

After spending time processing/correcting the raw(dng) file and rendering it to a jpeg or tiff, why keep the dng?

I may process the dng and render in both tiff and jpeg. Then, discard the dng."

I absolutely disagree. Why keep thousands of tiffs and jpgs? (My current collection of Raws - proprietary or dngs - is 30,000, which would probably be considered small for 20 years in digital.) If you have no immediate need for those rendered files, automatic conversions are just piling up deadwood. Once you have edited and backed up the Raws there are only a number of reasons why you might want to render RGB files; 16 bit tifs are needed if you want to do more editing in a pixel level editor and should be saved if can't or don't want to recreate that editing in the future, jpgs are needed for sharing as web postings or emails or for sending to a print lab. Once they have served that immediate purpose, the jpgs can be deleted, Should you need them again in the future, they can easily be rendered again in seconds.

Moreover, the technology is still evolving, but you cannot add more editing to a rendered file without doing a certain amount of damage - lesss to a 16 bit tif, more to a jpg. You can return endless times to a Raw without loss. The Raw is your source file which must always be preserved.

[Lumigraphics]

Well, this is wrong too. A RAW file is a starting point, but if I fix dust spots or acne or stray power lines or whatever, I'm not going to keep going back and doing that again. I save my retouched files as PSD format and those are my finished masters. I keep RAW files because sometimes I will go back and find a new one I want to use.

I've been a photographer for 39 years and have my old slides and negatives plus I'm well over 250,000 original RAW files. Storage is cheap and getting cheaper.

[elie_dinur]

You missed something that I wrote:

"16 bit tifs are needed if you want to do more editing in a pixel level editor and should be saved if (you) can't or don't want to recreate that editing in the future..." For purposes of this discusssion, I consider Tiff and PSD as equivalent.

[TheDigitalDog]

You missed something that I wrote:

"16 bit tifs are needed if you want to do more editing in a pixel level editor and should be saved if (you) can't or don't want to recreate that editing in the future..." For purposes of this discusssion, I consider Tiff and PSD as equivalent.

By @elie_dinur

Indeed! And for further reading for the OP:

http://digitaldog.net/files/TheHighBitdepthDebate.pdf

And perhaps more importantly for him, the idea of a raw workflow based on rendering the image. A must read:

http://www.lumita.com/site_media/work/whitepapers/files/pscs3_rendering_image.pdf

[TheDigitalDog]

Thanks everyone. I insist there be a way to predetermine how much space my picture library will be. Atleast to some degree.

You can do so, but the experts and experienced users here all disagree. Its a silly insistance IMHO. Considering the low cost of HD space, the fact you simply can't (nor should not) limit the number of images you may create or edit, that you have no idea how many iterations of edits you may make (limiting your creative considerations), the idea just doesn't wash.

It's like going on a trip with a film camera and deciding before getting there, you'll take one roll of film and promise no matter the circumstances, you will refuse to buy another roll, or a dozen rolls of film. Pointless, limiting, of no benefit.

Just buy a big drive you can afford and move on making images! You, like most of us here, will have to buy another, bigger drive sometime in the future unless you cease making images. Which will happen to all of us some day.

After spending time processing/correcting the raw(dng) file and rendering it to a jpeg or tiff, why keep the dng? 

After making an 8x10 print from a piece of film, why keep the film? See how silly a concept that is?