CRW/CR2 vs DNG

[tim]

What do you guys think about using these for archival of digital images? I have everything in CRW/CR2 at the moment, but I suspect as years go by support for the formats will be dropped. I'm wondering if I should be batch converting my images to DNG so I know i'll be able to read them in the future. Maybe holding off for a year or two would be a good idea, until DNG gains ground and settles down?

TIFF isn't a practical option, IMHO, it's just too large. I've no idea what size DNG is, I have to assume it's not too different from CRW.

[jbradc]

DNG is a proposed standard by Adobe, I would wait and see if any of the major camera companies (Canon, Nikon, Olympus, etc..) adopt the standard. As long as you keep the software (Photoshop, Capture One, EOS Viewer Utilty, etc...) you are using now to convert CRW/CR2 you will be fine.

[tim]

I tend to convert my best images to JPG for display on my website, so even if I couldn't open all my RAW files i'd still have the best of them visible.

[robertwgross]

I find TIF to be the most practical solution. It is certainly the most universal uncompressed format.

---Bob Gross---

[Jon]

Well, DPP doesn't support my D60's RAW, so Canon's already put that out to pasture. Somewhere along the line I'll need to decide on an alternative data format, and getting one that is camera-independent but allows me the flexibility of raw sounds good. How are TIFF or other "decoded" formats for reprocessing for colour balance, or exposure compensation when that's necessary? As a raw substitute, this would be important, since you're looking at (initially, at least) bulk converting everything to the new format, and if TIFF needs me to make the colour balance and exposure compensation calls up front it's a non-starter.

[CyberDyneSystems]

If anyone intends to convert the RAW data from ANY camera to a specific universal format and save that converted image as the archive.. the file type should be Tiff.

Whatever Adobe's flavor of the month is has not been time tested.

Frank;y I'm happy archiving my RAW files,. if for some reason I begin to feel that the platform on which the software required to work with these raw files is doomed,. it will be then that I will convert the whole shooting match to a PROVEN STANDARD.

Now I save th raw files,. and any files that I do convert to print,. I save the conversion as well. DVD's are cheap.

[CyberDyneSystems]

Jon ,. regarding the Tiff question..

It's a good one.. what I would suggest is if doing a "tweaked to the limits" conversion on all your files is out of the question,. then fro archiving a batch conversion leaving all the levels, saturation, contrast etc.. "flat" would be the safest tiff file.

Maybe doing them in batches where you could take the time to fix WB and exposure to as close to perfect would make sense as well.

Is Adobe proposing a method to make mass conversions of propreitary RAW files to there format?

If so .. wait a few years,. if this thing really does catch on then it may be the answer,.. but for now it looks to be too early to tell.

[mdr]

I agree. Why not backup every picture as RAW, TIFF and JPEG. You'll never loose.

[mdr]

As I said before, backup as tiff, jpeg and raw, and you'll vever loose... unless your backup media becomes antique.

[tim]

A 6MP RAW can work out to be a 40MB TIFF - that's prohibitive for many people, including myself. I think for now i'll just convert the best of the photos to high quality JPG just for when support for the CRW/CR2 format's dropped.

Edit - here's an interesting piece by Ken Rockwell that Lisa Marie posted in another thread. It makes for very interesting reading, whether you agree with him or not.

http://www.kenrockwell.com/tech/raw.htm

[jbradc]

At a minimum you need to back up as RAW and/or TIFF because JPEG is a compressed format. When you convert any image to JPEG you lose data and that affects quality. JPEG is a lossy compression method and RAW is a lossless compression method so no data is lost even though the file size is smaller with RAW.

[tim]

I understand compression quite well, it was covered in my degree. The point Ken Rockwell makes is JPG is a very, very widely used standard, is compressed using a lossy algorithm, but is pretty damn good at high quality. The whole article I linked to is worth reading, here's a small part.


If you're a tweaker you'd be interested to learn RAW and JPG also have the same effective bit precision. JPG has 8 bits per color per pixel and RAW may have 12 bits, but here's the big catch: RAW is 12 bit linear, and JPG is 8 bit log, gamma corrected or some other non-linear transform derived from the 12 bit linear data. Thus in the shadows where this might matter the two are the same, since the full 12 bit resolution in the dark areas is preserved by the non-linear coding. Even if the two formats differed in dark resolution the sensor noise is still greater than one LSB anyway making it a moot point.

[KennyG]

Ken has been banging his JPG drum for so long it has gone beyond boring.

Tim, storage is cheap, really cheap. There is no excuse for not having enough of it. For around the price of the cheap and cheerful 50 1.8 lens you can get 160GB of storage, or enough for 8,000 TIF files which are around 20mb each, not 40mb. Keep all RAW files and your best in TIF. At worst, keep the RAW and throw away everything else after a period of time as they can always be re-created if software is available in the future.

As far as Adobe is concerned, the price of bacon will have gone orbital before all manufacturers agree to toe this line.

[jbradc]

I understand compression quite well, it was covered in my degree. The point Ken Rockwell makes is JPG is a very, very widely used standard, is compressed using a lossy algorithm, but is pretty damn good at high quality. The whole article I linked to is worth reading, here's a small part.

There may be others in this forum that do not understand compression as well as you do, so that was for their benefit :)
You are correct that JPEG is a widely used standard and the quality is very good, but the truth is you can never get back what is lost when an image is compressed. For me JPEG is a destination, not a starting point, depending on how an image is going to be used JPEG may often be the best format. So as long as I have my uncompressed TIFF's or lossless RAW file I can make as many edits and JPEG's as I want and my original remains in tact.

[tim]

Tim, storage is cheap, really cheap. There is no excuse for not having enough of it. For around the price of the cheap and cheerful 50 1.8 lens you can get 160GB of storage, or enough for 8,000 TIF files which are around 20mb each, not 40mb. Keep all RAW files and your best in TIF. At worst, keep the RAW and throw away everything else after a period of time as they can always be re-created if software is available in the future.

If you have a laptop like me, you need external storage. I take a lot of photos, maybe 30GB per year RAW (guess), which would be 170GB of 16 bit TIFFs.

I think i'll just convert my best to TIFF, just in case.

[robertwgross]

If anyone intends to convert the RAW data from ANY camera to a specific universal format and save that converted image as the archive.. the file type should be Tiff.

I could not agree more.

TIFF (or TIF or Tiff) has been around for a long time, almost as long as CDS.

I archive my RAW files to CDR, but I vitually never use them again. TIFs get archived to DVD or other hard disks, and I refer to them occasionally. JPEGs are used a lot, but I almost never archive them.

---Bob Gross---

[robertwgross]

A 6MP RAW can work out to be a 40MB TIFF - that's prohibitive for many people, including myself.

6 MP RAW converts to 18 MB (in 8-bit-per-channel TIF) or 36 MB (in 16-bit-per-channel TIF). With the cheap cost of huge hard disks these days, 18 MB doesn't even scratch the surface.

---Bob Gross---

[boone]

You guys could give JPEG2000 a shot. It has a "lossless" storage format and from my tests the lossless JP2 file was nearly half the size of an uncompressed TIFF. There's a free Photoshop plugin:
http://www.fnordware.com/j2k/

It has worked well for me, but I haven't put a lot of images in that format because I'm concerned about the outstanding patent claims made by "Lizardtech" on the format. It might become another "crippled" GIF format. It would be nice to see the litigation concluded and the format become widespread.