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12-20-2013, 10:44 PM   #1
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RAW?

Something I have never dealt with but in the little reading I have done it seems like I need to learn alot more about this..... What is RAW, why should I be using it, good place to learn about it?

Thanks

Jd

12-20-2013, 10:56 PM   #2
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RAW is the full data recorded by a digital camera. The camera takes a picture in RAW, then (if you are saving as jpeg) makes a jpeg image from the RAW according to the parameters set in your camera, saves the jpeg on the memory card and then deletes the RAW.

Some cameras allow you to tweak the jpeg settings in the camera so you can tune how the camera cooks the jpeg, some cameras do not. Some cameras allow you to save both jpeg and RAW files, this is called RAW+ on Pentax cameras.

If you save the RAW files, they will show up as files in various formats. Pentax cameras use a proprietary format called .PEF or they can save in a more standard format called .DNG. Other camera makers use their own proprietary formats. The DNG format was developed by Adobe and intended to be a standard RAW format for all cameras rather than continuing with the multitude of proprietary file types.

A RAW file is just that, raw data, with usually a small jpeg thumbnail imbedded in it for viewing. To see the real image you must 'develop' the RAW file in some type of image processing software such Adobe Camera Raw, Lightroom, Faststone or a dozen others. During the processing you develop the RAW into a viewable image just like the camera would have if you set the camera to jpeg. The difference being that you can tweak the image to suit you and not be stuck with what the camera produces. You can also develop the RAW multiple times in different ways as the RAW itself is never changed only the output. Which also means you can develop an image today and then come back to it in six months with better skills and do it again.

As to where to learn more, Google is your friend, I think you can find more than you want to read.
12-21-2013, 12:14 AM   #3
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Adobe had a whitepaper titled "Understanding Digital Raw Capture" written by Bruce Fraser on its website as a pdf file, the direct link doesn't seem to work, but when it showed up as a search result from Google, I was able to follow the link and download the 3 page pdf. Failing that, you might want to start here Raw image format - Wikipedia, the free encyclopedia especially the first section. If your goal is to produce better photographic images, that should be enough to explain why serious photographers insist on saving images on their digital cameras in some RAW format or another.

Really, that's all RAW is, a category or type of file format designed for storing digital images without losing any of the information about the image provided by the camera. It's a bit of a generalization, but once a camera is too expensive for consumers who just want to point their camera at something and get a decent photograph, it has the capability of saving the image as a RAW file, instead of or in addition to saving it as a JPEG file. What you really need to understand are the disadvantages of JPEG files.

The Internet works best when images are stored in the smallest files possible while still displaying a recognizable image. Something called the Joint Photographic Expert Group developed mathematical formulas to compress millions of bytes of data representing digital images into files that could be less than 100,000 bytes in size. You can create JPEG files that are still in the megabyte range if you want, but if you need the reduce a file from a digital camera or scanner to one-hundredth of its original size or smaller, JPEG is the best way to do that. The real breakthrough was developing a formula that could discard individual pieces of information that didn't take away from the image as the human eye sees it, and save repetitive information that was still important in a type of digital shorthand. The shorthand is compression, and since not all of the original information is saved, it is called lossy compression, compared to lossless compression where no information is discarded.

The information your digital camera gets from the sensor doesn't produce a recognizable image by itself. The camera has to process the "raw" information from the sensor to produce a file that can be displayed on your computer or sent to a printer. From the camera's standpoint, the difference between RAW files and JPEG files is how much processing the camera does before it saves the image to a memory device. For JPEG files, the result is a file that doesn't need any further modification in order to be viewed or printed. For RAW files, further processing needs to be done by a computer before the image can be displayed.

Why go through the bother of converting RAW files? Because computer programs can do a much better job of adjusting exposure and sharpness, correcting different types of distortion, removing dust spots or red eye and so on, if all of the information produced by the camera's sensor is available for manipulation. It's like cutting a board, if you just measure the next cut from the last one, all of your measuring errors start to add up. You get better results by measuring all of the cuts before starting the saw. You can still use software to manipulate JPEG files, but nothing will fit like it should afterwards.

There are several good options for software to convert and clean up RAW files, and the best ones will make automatic adjustments on groups of files for you without too much trouble. And once you start experimenting with this software, doing what is called post-processing, you will be ashamed to admit that in the past you just printed, posted or emailed pictures without trying to make them look better. If you are already familiar with software post-processing, you can ignore the simplistic background information I've provided, but remember that post-processing JPEG files should be a last resort, not the way you do things.

Finally, in the beginning, camera manufacturers developed their own proprietary RAW file formats so that features specific to their cameras could be used in software written for their cameras. DNG is a universal RAW file format that came out much later, and cameras that can save photos in either their own format or as DNG require more built-in computing power. There are computer programs that will convert various RAW file formats into the DNG format, but that is another step in the process of getting photos from your camera to a human being looking at them. And really, in the end, it comes down to either the most convenience, or the most enhancement of your photos, that determines whether or not you use RAW files.
12-21-2013, 04:20 AM   #4
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As the others said, RAW files have "all" the data originally recorded from the sensor. It is sort of like a digital negative -- lots of stuff there, but no way to really see it until it is developed. Your camera is actually a little computer that is designed to rapidly develop these RAW files into jpeg images. It can do a pretty good job with it and obviously produces a lot smaller files than the original RAW file, but it does throw away a bunch of data during the conversion. What this means is that if you have an image that has shadows that you want to bring up, or really weird white balance that you need to correct, it may be tough to do with the jpeg, because the details just might not be there that were there originally.

There are a lot of RAW developers. One, based on Silky Pix, is distributed with Pentax cameras. I personally like a combo of Lightroom and Nik Effects. As to learning how to get the most out of them, there are several books out there that can help you learn the features of these programs, but figuring out what works best and how to achieve the look you want takes time experimenting. Although, once you figure it out, you can develop large numbers of files fairly quickly.

12-21-2013, 04:59 AM   #5
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Regard RAW (and DNG, which is short for Digital Negative) as the digital counterpart of film negatives. IMHO JPG is like shooting an image and thow away the negative afterwards. RAW is your digital negative, you can develop it time after time with much more data and control. The good news is that you have way more data to work with (as most DSLR`s record typically 12/14bit of information) where as the JPG is only 8bit (so the jpg lost data during the in-camera conversion which cannot be retrieved). The "downside" is that you have to develop (postprocessing) every RAWfile which, offcourse, takes more time.

To me the latter is not a problem, as I prefer more data and control over my final image but that`s a personnal preference. Besides, in the rare case I only want to convert to JPG there is allways an easy option in the software.

Last edited by TenZ.NL; 12-21-2013 at 05:31 AM.
12-21-2013, 06:54 AM   #6
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Read this article it may help your understanding Understanding RAW Files Explained

I shoot mainly in raw, with that said keep in mind if you shoot raw then every photo you shoot Will need to be post processed and it is best to have a very good post processing software if you are going to venture that direction.

Why shoot in raw?
As others have mentioned it is Lossless and all of the data is maintained.

How does that help you?
Given all of the data is there then it gives you much more latitude in making post processing corrections or adding creative aspects to the exposure of your photos prior to conversion processing for printing or uploading to the net. For example lets say you blew the exposure on a shot and it is too dark or way too light. By shooting in raw you can adjust that exposure easily by 2 stops or possibly more and make other corrections to compensate for any possible blown out highlights or too dark areas. Where as if you try that with a Jpeg file it becomes much more difficult to impossible normally to correct. After saying this it is possible to open a jpeg and process it in a raw editor which I find gives me a little more latitude or it's just I have become very used to processing in ACR 1st...LOL

Sometimes I like to shoot in jpeg to utilize some of the nifty filters and settings made for jpeg my camera has to offer. In either case whichever you decide to use I suggest, if you don't know this already, anytime you make corrections to a photo save that file as something else... That way anytime you want to go back and make changes down the road those files you downloaded from your camera are still there in their original untouched version for you to work from.
12-21-2013, 07:49 AM - 1 Like   #7
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I think of it like raw vs pre cooked meat. Pre cooked meat might taste good and be ready instantly but if youre a chef you don't serve a pre cooked cut of meat, you start fresh and season to your liking. Jpgs, like pre cooked meat, will be pretty good out of the box but if you're good in the kitchen and have the time to cook a meal why not?

Last edited by Pete_the_Irish_Guy; 12-22-2013 at 03:12 AM. Reason: for punctuation
12-21-2013, 11:25 AM   #8
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Another thing; the difference between 8 and 12 bits of information might not sound like much, but each extra bit will double the amount of information. So 12 bits will contain 16 times more information than 8 bits will. And 14 bits 64 times more.

All that extra information will enable you to save some pictures that would go right in the digital waste bin as JPEGs.

12-21-2013, 12:15 PM   #9
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QuoteOriginally posted by savoche Quote
each extra bit will double the amount of information
Sorry, but that's a rabbit hole you don't want to go into. You don't double the amount of pertinent information by adding another bit of resolution, you only add one more attribute about the pixel that can be stored as a yes or no. The binary values for however many attributes (or distinct pieces of information) are being stored for that pixel can be converted into an integer, and the magnitude of the integer doubles with each bit of information you add. Image information for each pixel is stored as quantities of red, green and blue light, but twice as much blue doesn't look twice as blue or twice as bright. Increasing the number of bits does allow the software converting a RAW file into an image for display to produce a more accurate depiction of the image, but the degree of improvement doesn't go up by powers of two. Thinking of it as increasing the dynamic range by a factor of one for every bit added, is closer to what actually happens.
12-21-2013, 12:38 PM   #10
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QuoteOriginally posted by RGlasel Quote
Sorry, but that's a rabbit hole you don't want to go into. You don't double the amount of pertinent information by adding another bit of resolution, you only add one more attribute about the pixel that can be stored as a yes or no. The binary values for however many attributes (or distinct pieces of information) are being stored for that pixel can be converted into an integer, and the magnitude of the integer doubles with each bit of information you add. Image information for each pixel is stored as quantities of red, green and blue light, but twice as much blue doesn't look twice as blue or twice as bright. Increasing the number of bits does allow the software converting a RAW file into an image for display to produce a more accurate depiction of the image, but the degree of improvement doesn't go up by powers of two. Thinking of it as increasing the dynamic range by a factor of one for every bit added, is closer to what actually happens.
Certainly. You won't double the amount of blue or double the dynamic range or any such thing. But you will be able to record more values within the range you've got, and that can in some situations be enough to get usable information out of something that would be completely uniform colour in a a jpeg. This is most noticeable near completely white and completely black (and thus increase dynamic range somewhat), but detail can be rescued at all levels in between as well.

No miracles promised, though. And even if the difference (in numbers) is vastly bigger between 12 and 14 bits than it is between 8 and 12 bits, the real life difference is bigger going from 8 to 12 bits than from 12 to 14.

But in short, what I'm trying to say is: The difference is real. Especially for someone like me who doesn't expose perfectly every time.
12-21-2013, 12:50 PM   #11
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QuoteOriginally posted by savoche Quote
The difference is real
It certainly is, but if you are dipping your toes into post-processing RAW files, you may not notice the temperature difference immediately.
12-21-2013, 01:04 PM   #12
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QuoteOriginally posted by Oldbayrunner Quote
...keep in mind if you shoot raw then every photo you shoot Will need to be post processed...
If you mean to convert the RAW to JPG or TIF then, yes. Otherwise, no. The majority of RAWs I produce don't need to be PPed or at least no more or often than I would PP JPGs which come straight out of the cam.
12-21-2013, 01:40 PM   #13
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I will only point out that post-processing is no more difficult or time-consuming than editing a jpg, the raw software may have more editing options, and you can convert a batch of files with a click or two in just about any raw processor, hands-free, while you make coffee.

By the time I chimp, rename, organize and back up images, the actual PP time is only a small percentage of the time involved. And leveling the horizon or spotting for dust or Coke cans is needed in any format.

Some software is free, such as FastStone Image Viewer, Screen Capture, Photo Resizer ... or Gimp, others cost a bit under $80 but may have online tutorials and third-party books (Photoshop Elements), or handy categorizing capabilities of Lightroom. Some have free downloadable trials.

Last edited by SpecialK; 01-07-2014 at 09:26 PM.
12-21-2013, 06:56 PM   #14
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QuoteOriginally posted by Schraubstock Quote
If you mean to convert the RAW to JPG or TIF then, yes. Otherwise, no. The majority of RAWs I produce don't need to be PPed or at least no more or often than I would PP JPGs which come straight out of the cam.
That's what I meant
12-21-2013, 08:38 PM   #15
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Thanks everyone... obvious I have alot of learning to do about this, but did take a few pics in the RAW format so I have something to play with... Probably better off learning how to operate my camera first...lol...
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