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10/13/2006 02:47:02 PM · #1 |
I'm a RAW newbie. I'm interested in the salient differences between RAW and .jpg at capture time so want to compare the same picture captured simultaneously in RAW and in .jpg for comparison.
The extracted .jpg from a RAW+jpeg file is different from the RAW converted picture using "camera settings" with Adobe CS2's raw image converter.
Questions:
1-Why is the extracted .jpg different from the RAW converted file using camera settings?
2-For those that say, "RAW is 'better' than .jpg, I'd never go back", can you specify your MAIN reasons for saying that?
I understand the inherent technical advantageous of RAW over .jpg. For that alone I will use it for better enlargements, color transitions and prints. But I'm thinking those advantageous make very little difference in the type of web graphics we create for DPC challenges. Am I wrong? If so, why?
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10/13/2006 03:00:58 PM · #2 |
I don't know exactly, but generally I believe that JPEGs have more processing in camera to make them palatable to the end user. This might include sharpening or boosted contrast, etc.
The raw file however should just be what is captured, and I guess the "in camera" will still not be the same as the jpeg because the jpeg is processed. |
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10/13/2006 03:22:39 PM · #3 |
A JPEG file is compressed (I believe, 8bit), the RAW file gives you all the details (I think 24bit). If you want to modify (process) the RAW file you have more data to work with giving you better details. Eventually you'll convert the RAW file to a TIFF format (at least that's how I see it) that is a 16bit file. Still more data on-hand to manipulate than an 8bit JPEG. Make additional processing changes if desired using a photo editing program (PS, PSP, GIMP, etc..). When finished you can save as a JPEG. Some steps in PP (at least using PSP X) will require reducing the file to 8bit first (from TIFF 16bit) - Histogram adjustment is one, using the Neat Image plugin is another, borders also...
Hope some of that makes sense. No guarantees on it being correct. :D |
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10/13/2006 04:03:33 PM · #4 |
Originally posted by stdavidson:
Questions:
1-Why is the extracted .jpg different from the RAW converted file using camera settings? |
1. What software are you using to convert the RAW file to JPG?
2. Where are you getting the camera settings from, and how are they being applied to the conversion?
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10/13/2006 04:15:16 PM · #5 |
Originally posted by glad2badad:
A JPEG file is compressed (I believe, 8bit), the RAW file gives you all the details (I think 24bit). |
JPEG compression has nothing to do with the bit-depth (color range) of the image -- an "8-bit" image is actually 8 bits per channel or a 24-bit (6.7 million colors) color space. "16-bit" color is likewise 16 bits/channel, or 48-bits overall. |
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10/13/2006 04:16:33 PM · #6 |
Originally posted by micknewton:
Originally posted by stdavidson:
Questions:
1-Why is the extracted .jpg different from the RAW converted file using camera settings? |
1. What software are you using to convert the RAW file to JPG?
2. Where are you getting the camera settings from, and how are they being applied to the conversion? |
I'm not using anything to convert to .jpg. I'm extracting the imbedded .jpg captured by the camera for comparison. The .jpg is unmodified and of highest quality just as I would capture if I were not using RAW.
For RAW conversion I am using CS2's built-in RAW image converter with default settings. The difference from .jpg shows up before it is saved in any format. My defaults are unchanged from Adobe's distributed software (for Canon 10D .crw RAW). In other words, I'm doing a "straight" conversion from RAW.
The converted RAW file has a different histogram display so that is how I know it is not the same.
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10/13/2006 04:19:47 PM · #7 |
| The embedded JPEG is probably modified by your camera settings, exactly as if you were shooting JPEG only and not capturing the RAW file. Those settings are probably not identical to the default settings in the RAW converter. |
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10/13/2006 04:28:46 PM · #8 |
For simplicity's sake, when I say "8-bit" it means 8-bit/channel and "16-bit" means 16-bit/channel. That makes it easier to know what you are really talking about regardless the number of channels your color space has.
For example, RGB has 3 channels and CMYK has 4. In both I'd call it "8-bit" color, rather than 24-bit in RGB and 32-bit in CMYK which is more confusing.
For the record, .jpg is limited to "8-bit" sRGB color (The "s" is for small).
Note:
Hmmmmm... maybe I answered my own question. Maybe the issue is that the imbedded file is already 8-bit sRGB limited but the RAW is not (yet).
Message edited by author 2006-10-13 16:49:29.
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10/13/2006 04:42:50 PM · #9 |
Originally posted by stdavidson:
Questions:
1-Why is the extracted .jpg different from the RAW converted file using camera settings? |
Different program doing to processing: the program on your PC can take more time and do a better job (*potentially*).
Originally posted by stdavidson:
2-For those that say, "RAW is 'better' than .jpg, I'd never go back", can you specify your MAIN reasons for saying that? |
White balance! Seems a small reason, but really is probably #1 for me. You can adjust the actual WB in RAW processing. Really recovering a JPEG with a WB more than just a tiny bit off is not possible.
There are tons of reasons I love RAW now, and I'm sure others will continue to tell you many of those.
Discover your own reasons to use RAW, or not to, as the case may be. JPEG is nice for snapshots, but even then I sometimes wish I had the greater color-precision of raw. |
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10/13/2006 04:52:25 PM · #10 |
Originally posted by skylen:
Originally posted by stdavidson:
2-For those that say, "RAW is 'better' than .jpg, I'd never go back", can you specify your MAIN reasons for saying that? |
White balance! Seems a small reason, but really is probably #1 for me. You can adjust the actual WB in RAW processing. Really recovering a JPEG with a WB more than just a tiny bit off is not possible.
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Steve, did you ever shoot something indoors and it has that 'yellowish' tint to it? That's from the light bulbs in your home. If you're shooting in RAW, you can make the WB change to whatever you want....from blue to white to yellow all the way up to orange.
Message edited by author 2006-10-13 16:54:41.
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10/13/2006 04:54:54 PM · #11 |
Originally posted by skylen:
White balance! Seems a small reason, but really is probably #1 for me. You can adjust the actual WB in RAW processing. Really recovering a JPEG with a WB more than just a tiny bit off is not possible. |
I'd agree. That and its associated color temperature adjustment will probably be my main post processing reason to. But I've seen people say in the forums that WB was not that big a deal to them but still prefer RAW.
I'm just trying to get a handle on why folks like RAW so I can judge for myself what will be most useful to me.
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10/13/2006 04:59:41 PM · #12 |
Originally posted by stdavidson:
2-For those that say, "RAW is 'better' than .jpg, I'd never go back", can you specify your MAIN reasons for saying that? |
I use RawShooter Premium (no longer on the market, but you can still get RawShooter Essentials): After shooting a couple hundred pictures at a wedding, I can very quickly go thru my raw images, make quick adjustments to exposure and white balance and produce a set of proofs that are of high enough quality that I can show them in the slide show running at the reception only a few hours later.
If I were to shoot jpeg, I'd have to manually edit each image in order to adjust exposure or white balance. And the quality of the image would degrade in the process because I have edited a jpeg and saved it out as a new jpeg. (so it will have been compressed twice at this point)
For me, raw is a faster workflow and higher quality output.
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10/13/2006 05:00:32 PM · #13 |
Originally posted by MrEd:
Originally posted by skylen:
Originally posted by stdavidson:
2-For those that say, "RAW is 'better' than .jpg, I'd never go back", can you specify your MAIN reasons for saying that? |
White balance! Seems a small reason, but really is probably #1 for me. You can adjust the actual WB in RAW processing. Really recovering a JPEG with a WB more than just a tiny bit off is not possible.
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Steve, did you ever shoot something indoors and it has that 'yellowish' tint to it? That's from the light bulbs in your home. If you're shooting in RAW, you can make the WB change to whatever you want....from blue to white to yellow all the way up to orange. |
Yes, we all have, haven't we? lol! Having worked in .jpg for so long I've made the effort to learn how to correct for various color cast problems.
I'm still in the experimental stage deciding if WB (temperature) adjustments when converting from RAW is 'better' than normal color cast corrections within PS. My guess is that it is, but how much I don't know.
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10/13/2006 05:00:47 PM · #14 |
This isn't the best example but......you can go from
this (default RawShooters Essential settings) 
to this 
to this 
and everything in between. It's not just WB, it's exposure compensation, highlight/shadow contrast, saturation, sharpening, and a couple more.
TECHNICALLY, you can make those changes and say it's 'straight from the camera'.....or am I wrong?
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10/13/2006 05:02:28 PM · #15 |
Originally posted by stdavidson:
I'm a RAW newbie. I'm interested in the salient differences between RAW and .jpg at capture time so want to compare the same picture captured simultaneously in RAW and in .jpg for comparison.
The extracted .jpg from a RAW+jpeg file is different from the RAW converted picture using "camera settings" with Adobe CS2's raw image converter.
Questions:
1-Why is the extracted .jpg different from the RAW converted file using camera settings?
2-For those that say, "RAW is 'better' than .jpg, I'd never go back", can you specify your MAIN reasons for saying that?
I understand the inherent technical advantageous of RAW over .jpg. For that alone I will use it for better enlargements, color transitions and prints. But I'm thinking those advantageous make very little difference in the type of web graphics we create for DPC challenges. Am I wrong? If so, why? |
A Jpg is a compressed graphics file the name stands for something Johansenberg (something like that) processed graphic (or is it Gif), and is actually a compression of a Gif (graphics interchange format)devloped by compuserve as a way to trade pictires on the orginal compuserve service way back when. When a image is converted to Jpg data for color and details are stripped from the image in theory in a way that you cant see a diffrence, but the ammount of compression can change that and make them look way diffrent. The whole point behind a JPG is to make the file size smaller so it can be transported easier via disk or transmitted quicker because it is smaller while still a high quality. RAW on the otherhand is closer in line to a TIFF but basically speaking it is exactly what the camera see's plus the adjustments in contrast and noise ect you have set on your camera. Because it is not compressed it is a larger file but has more of the image details and color data ect to work with, it is the closest thing to a negative you will get in a digital camera, where the jpg is more along the lines of a processed already devloped negative. Shooting Raw has superior abilities for post processing as a result where in a jpg because of the data compression and removal some things are more locked in and not as flexible. When you convert a RAW to JPG your basically fine tuning what you want to keep vs letting the camera generic compression algorythm make the choices for you. |
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10/13/2006 05:04:24 PM · #16 |
I would say is is not the same as working from the camera more like processing it from a negative to get it to look the way you want vs painting over an already processed photo.
Message edited by author 2006-10-13 17:05:16. |
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10/13/2006 05:15:15 PM · #17 |
Originally posted by nemesise1977:
A Jpg is a compressed graphics file the name stands for something Johansenberg (something like that) processed graphic |
For the record, JPEG stands for Joint Photograhic Experts Group That is the name of the group that defined the .jpg standard.
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10/13/2006 05:40:21 PM · #18 |
Originally posted by stdavidson:
Originally posted by nemesise1977:
A Jpg is a compressed graphics file the name stands for something Johansenberg (something like that) processed graphic |
For the record, JPEG stands for Joint Photograhic Experts Group That is the name of the group that defined the .jpg standard. |
I stand corrected... Not sure why I was that far off I know back in 1990 or so I had a dos util that was command line driven that called it by that name (johansen what ever) maybe that was just the name of that specific engine...was a long time ago, funny had the name for the ext wrong for quite a while...lol , still it is a compressed image.
where is a good description on how it works
//en.wikipedia.org/wiki/JPEG |
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10/13/2006 05:50:45 PM · #19 |
Originally posted by stdavidson:
Originally posted by micknewton:
Originally posted by stdavidson:
Questions:
1-Why is the extracted .jpg different from the RAW converted file using camera settings? |
1. What software are you using to convert the RAW file to JPG?
2. Where are you getting the camera settings from, and how are they being applied to the conversion? |
I'm not using anything to convert to .jpg. I'm extracting the imbedded .jpg captured by the camera for comparison. The .jpg is unmodified and of highest quality just as I would capture if I were not using RAW. |
I thought you said that you were comparing the JPG that came out of the camera (the one embedded in the .crw file) to a JPG that you made from the RAW file using ACR with default settings.
Originally posted by stdavidson:
For RAW conversion I am using CS2's built-in RAW image converter with default settings. The difference from .jpg shows up before it is saved in any format. My defaults are unchanged from Adobe's distributed software (for Canon 10D .crw RAW). In other words, I'm doing a "straight" conversion from RAW.
The converted RAW file has a different histogram display so that is how I know it is not the same. |
1. In ACR, if you don't save the file to some format (tiff, jpg, etc.), than you haven't really done any conversion, just applied settings.
2. In ACR, the default settings for the 10D camera may be, and probably are, different from the actual camera settings that were used to create the photo.
3. The software doing the conversion in-camera is different from the ACR software in CS2. My guess is that different algorithms working on the same data = different results.
Of course, I'm probably wrong about everything I've said, but I wanted to type something anyway. :D
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10/13/2006 05:56:24 PM · #20 |
Originally posted by micknewton:
I thought you said that you were comparing the JPG that came out of the camera (the one embedded in the .crw file) to a JPG that you made from the RAW file using ACR with default settings. |
Yeah... I gotta work on thos communications skills! :)
Originally posted by micknewton:
1. In ACR, if you don't save the file to some format (tiff, jpg, etc.), than you haven't really done any conversion, just applied settings.
2. In ACR, the default settings for the 10D camera may be, and probably are, different from the actual camera settings that were used to create the photo.
3. The software doing the conversion in-camera is different from the ACR software in CS2. My guess is that different algorithms working on the same data = different results.
Of course, I'm probably wrong about everything I've said, but I wanted to type something anyway. :D |
I dunno... sounds pretty reasonable to me. :)
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10/13/2006 07:03:30 PM · #21 |
The nearest equivalent as far as I can express it is that RAW is like developing your own film, and JPEG is like getting it done at a lab. The immediate processing with .jpg is done according to some bloke's ideas as they sit a lab in Japan, probably, with the concerns of the everyday snapshotist at heart. RAW has basic processing too, it should be acknowledged, but it is minimal - or minimal compared to the .jpg results.
White balance and so on are a boon too - you don't have to 'correct' for it, you just change the settings. And fractional alterations in exposure can also be 'corrected', obviously depending on your taste.
But what you really win is detail - and that actually should go without saying. A high quality jpg from my camera is about 2MB, and a RAW is around 7.5. I know that's not a completely accurate measure, but I absolutely feel that the more detail you start with, the more your image will survive the later processing. The point, really, of the original capture, to me, is to get as much information recorded as possible, so that you can decide what to discard later.
Of course, as with fans of all types of photography, you can decide that the particular processing engine of a particular camera suits your style - the graininess of my new Oly 320 for instance really entrances me, although it would annoy bery many people I suspect. Just as there are people who really enjoy the quality of Polaroid photographs. Each to their own - but if you want detail and control, then RAW should really be played with for a while, to let it become customary, and then to see if you can bear to switch back.
Ed |
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10/13/2006 07:20:32 PM · #22 |
| I feel that shooting in RAW, converting to 16 bit TIFF, processing, saving in 16 bit TIFF, and then converting and saving to JPEG 12 gives me the best possible quality while keeping artifacting at bay. Converting from RAW to JPEG 12 and then processing landed me up with plenty of rejections when submitting stock images to reviewers.... but the route above landed me up with zero rejections. |
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10/13/2006 07:27:35 PM · #23 |
I can only echo dwterry and say that, overall, RAW seems to be actually an easier way to go. One can preview and delete images within the RAW converter, then make alterations and set the images converting in the queue. In JPEG, one would have to open each one individually, make changes, then save (or remember to 'save as', if shooting for a challenge here).
For challenges, there probably isn't a massive amount to gain using RAW, but one can still take advantage of the 'two develops blended' tactic in advanced editing.
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10/15/2006 08:32:35 AM · #24 |
I just started playing with RAW myself and I am using RawShooter Essentials. This may have been covered before but I was wondering if the adjustments that I make on the image in RSE alter the exif data or does it leave it as a clean original? Nowhere have I been given an option to save or save over while working ont he RAW image so I am assuming that the files are still validation clean.
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10/15/2006 08:52:10 AM · #25 |
Originally posted by timfythetoo:
I just started playing with RAW myself and I am using RawShooter Essentials. This may have been covered before but I was wondering if the adjustments that I make on the image in RSE alter the exif data or does it leave it as a clean original? Nowhere have I been given an option to save or save over while working ont he RAW image so I am assuming that the files are still validation clean. |
No, you don't physically change the photo itself. If you look at the folder you have those RAW files, you will see another folder (.RWSettings). Those are the settings you changed saved for the next time you open that folder. If you delete that folder (the .RWSettings), you delete the settings and the photo will go back to its original form.
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