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03-23-2010, 08:05 PM   #1
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My 2nd dumb noob question :-)

OK. I've been shooting a long time, but more just experimenting (for a few decades ) than really knowing what I'm doing. Ever since switching to digital, I've dealt with jpeg images. Now that I have my spiffy new K-7 I'm starting to look into RAW editing. I understand that the RAW format stores the info, but when I look at the images I can't really tell any difference between the RAW image and the jpeg image. It looks like there's A LOT of stuff to learn for this RAW manipulation. What can I do with RAW editing that is significantly different than jpeg editing? I understand that all you expert photogs will lean toward RAW, but is it worth the effort for someone like me who's mainly interested in a hobby? Any info would be appreciated. Thanks a lot.

03-23-2010, 08:09 PM   #2
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There are plenty of posts around here that will tell you that if you can set-up your jpg engine well in the camera you don't need RAW... but if you ever happen to completely blow the white balance you can fix it in RAW, not as well in JPG. RAW with lightroom is not too complicated, same with the pentax program that came with the camera... but if you want no fuse, straight to web from camera you need jpg... hope that is clear as mud
03-23-2010, 08:11 PM   #3
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PS I shoot Jpg 90% of the time, unless I want to make sure I have options, like at the hockey rink, then i shoot RAW +jpeg

PPS Not a dumb question... if you can get a straight answer well that would be amazing... it all depends on your personal work flow...
03-23-2010, 08:54 PM   #4
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QuoteOriginally posted by kyricom Quote
OK. I've been shooting a long time, but more just experimenting (for a few decades ) than really knowing what I'm doing. Ever since switching to digital, I've dealt with jpeg images. Now that I have my spiffy new K-7 I'm starting to look into RAW editing. I understand that the RAW format stores the info, but when I look at the images I can't really tell any difference between the RAW image and the jpeg image. It looks like there's A LOT of stuff to learn for this RAW manipulation. What can I do with RAW editing that is significantly different than jpeg editing? I understand that all you expert photogs will lean toward RAW, but is it worth the effort for someone like me who's mainly interested in a hobby? Any info would be appreciated. Thanks a lot.
With some programs, what you see on the screen might just be a JPEG, the one embedded in the RAW file.

RAW files have more bits and therefore more information, the color temperature is not fixed, and they are not pre-processed by the camera. Most of the time, the advantage of having the RAW image to edit is that it will give you a better image when something has gone wrong.

One example that I recall clearly was my 191st photo with the camera. I was shooting JPEG because I was traveling with a single 1Gb card. The previous night I had set a custom WB to eliminate the color cast of a streetlight. Then the next day I forgot about that and took a photo of a brick building on a sunny morning. It was a startling blue color. I realized my mistake, fixed the camera and took another shot. The first photo looks better after processing, but nowhere near the second.

It's pretty easy to get a JPEG from a RAW file. I think the Pentax software will do it using the settings from your camera, so with one extra step you can always get a JPEG. But you can't get the adjustability back when you start from an already developed JPEG. (If you had someone else developing your film, they usually would do some similar tricks to your prints unless you told them not to.)

03-24-2010, 01:16 PM   #5
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QuoteOriginally posted by Just1MoreDave Quote
With some programs, what you see on the screen might just be a JPEG, the one embedded in the RAW file.
Actually this is true for almost all applications. When you're looking at a RAW file in a picture viewer (for example, on the screen of your camera), you're actually viewing the embedded thumbnail in the RAW file, which is a horribly compressed JPG. Until the RAW file has been processed into a final format, it only looks like a crazy grayscale picture.

edit: it's easy to see that you're looking at a super-compressed thumbnail. Take 2 pictures of something, one in JPG and one in RAW. Try and get the exact same picture in both shots. Then in Playback mode, zoom right into the RAW picture, at like x16 magnification. Then use the front e-dial to switch to the JPG picture. It'll maintain your position and magnification, and you can see for yourself how bad the RAW file looks compared to the JPG, since you're really seeing the embedded thumbnail.

If you shoot in RAW+, when you review your pictures, you're actually viewing the JPG file, not the embedded thumbnail in the RAW file.

QuoteOriginally posted by Just1MoreDave Quote
RAW files have more bits and therefore more information, the color temperature is not fixed, and they are not pre-processed by the camera. Most of the time, the advantage of having the RAW image to edit is that it will give you a better image when something has gone wrong.
Technically, RAW files have fewer bits than a comparable JPG. While the RAW file may have more bits per channel, it only has information on ONE channel for each pixel. Meanwhile, a JPG or TIF file has information on 3 channels for each pixel (red, green and blue). This is why an uncompressed TIF file ends up being so much bigger than its root RAW file. If you want to get even more technical, RAW files have no colour information at all, just a single luminance value for each pixel. It's up to the RAW processing software to determine how those simple values translate into a colour picture (and that's where the Bayer array thing comes in).

I *think* the K-7 generates 14 bit RAW files, but I could be wrong. It might only be 12 bit. Meanwhile, a JPG file has 8 bits per channel, for a total of 24 bits per pixel. And a TIF file can have 8 or 16 bits per channel, for a total maximum of 48 bits per pixel.

Don't mind me, I'm just nit-picking here

Last edited by GoremanX; 03-24-2010 at 01:31 PM.
03-24-2010, 03:43 PM   #6
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QuoteOriginally posted by kyricom Quote
OK. I've been shooting a long time, but more just experimenting (for a few decades ) than really knowing what I'm doing. Ever since switching to digital, I've dealt with jpeg images. Now that I have my spiffy new K-7 I'm starting to look into RAW editing. I understand that the RAW format stores the info, but when I look at the images I can't really tell any difference between the RAW image and the jpeg image.
Indeed - that's because half the applications in the world that purport to show you a RAW file area actually showing you the JPEG preview embedded within the RAw file by the camera, and even the applications that show you the RAw data need to convert it to the equivalent of JPEG in order to be able to display it on your monitor or print it. You're just putting off doing the same conversion the camera would have done for you had you shot JPEG. The advantage of RAW cannot be seen until you try *processing* the file. certain types of processing (like jlarge scale changes to white balance or exposure) can be done *MUCH* better if they are done on the RAW image before it is converter to a visible form, and this is what RAW processing programs do.

QuoteQuote:
I understand that all you expert photogs will lean toward RAW, but is it worth the effort for someone like me who's mainly interested in a hobby?
If you intend to do a lot of PP, then you'll get better results if you do it in RAW. If you don't intend to do much PP, then RAW provides no advantage.
03-24-2010, 05:37 PM   #7
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QuoteOriginally posted by Marc Sabatella Quote
If you intend to do a lot of PP, then you'll get better results if you do it in RAW. If you don't intend to do much PP, then RAW provides no advantage.
Marc

I think the OP wants to know specifically what type of PP really demands RAW, you have made some good points in the past, such as sharpening, contrast and saturation beyond what is possible in camera, etc...

I can also envision high key and low key portraits because there is too much risk of getting blocks of tones as opposed to smooth transitions when working at either extreme of the histogram in JPEG.

Aside from disaster recovery, where I think all agree you will get a better saved image (but probably still not great) from RAW, it is these points which need to be fleshed out.
03-24-2010, 06:09 PM   #8
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QuoteOriginally posted by Lowell Goudge Quote
Marc

I think the OP wants to know specifically what type of PP really demands RAW, you have made some good points in the past, such as sharpening, contrast and saturation beyond what is possible in camera, etc...

I can also envision high key and low key portraits because there is too much risk of getting blocks of tones as opposed to smooth transitions when working at either extreme of the histogram in JPEG.

Aside from disaster recovery, where I think all agree you will get a better saved image (but probably still not great) from RAW, it is these points which need to be fleshed out.
A couple of things that come to mind. If you take a shot with the wrong white-balance setting, it is much easier to correct this with a RAW file. Some color casts can be improved on a jpeg, but with RAW it is much easier.

I discovered that, with my K10D, when shooting in RAW, I can often deliberately underexpose an image by two stops in low light. This allows me to keep the shutter speed fast enough that the SR will effectively cancel out the camera movement. There is, after all, a limit to how much SR can realistically do. Then, in PP, I can bring the exposure back up to where it should be. With a jpeg, too much detail is lost.

03-24-2010, 06:14 PM   #9
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QuoteOriginally posted by noblepa Quote
A couple of things that come to mind. If you take a shot with the wrong white-balance setting, it is much easier to correct this with a RAW file. Some color casts can be improved on a jpeg, but with RAW it is much easier.

I discovered that, with my K10D, when shooting in RAW, I can often deliberately underexpose an image by two stops in low light. This allows me to keep the shutter speed fast enough that the SR will effectively cancel out the camera movement. There is, after all, a limit to how much SR can realistically do. Then, in PP, I can bring the exposure back up to where it should be. With a jpeg, too much detail is lost.
deliberate under exposing and trying to pull data out of the shadows is really one area where RAW is needed, but why not just up the ISO, after all this would be a better approach, and you get more resolution than pulling the data out of the shadows, with no impact on grain, Someone posted shots that proved this.

as far as WB, I find that even under the worst lighting, JPEG has enough data to correct without any issues. at least using PSP X and higher, it is just one click of the mouse. I will point out that while fine adjustment is perhaps slightly reuced, that is only a problem if you have to match exactly WB in two differeltly misadjusted shots, back to a common point to print them side by side. It is like setting the color on a TV, it is easy to set one to an acceptable level, but near impossible to make two identical.
03-24-2010, 06:57 PM   #10
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The only time you see the actual RAW image is in something like Adobe Camera Raw. That's the unadulterated file.

I shoot RAW + for everything. Just a habit. I've got enough memory cards and HD space I am not worried about filling up my HD. I shoot RAW because a lot of times I am combining images for different types of effects. I want all the info I can get.

I use the jpeg for those times I need to send a quick email and the PP doesn't matter.
03-25-2010, 12:07 PM   #11
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QuoteOriginally posted by GoremanX Quote
...edit: it's easy to see that you're looking at a super-compressed thumbnail. Take 2 pictures of something, one in JPG and one in RAW. Try and get the exact same picture in both shots. Then in Playback mode, zoom right into the RAW picture, at like x16 magnification. Then use the front e-dial to switch to the JPG picture. It'll maintain your position and magnification, and you can see for yourself how bad the RAW file looks compared to the JPG, since you're really seeing the embedded thumbnail.

If you shoot in RAW+, when you review your pictures, you're actually viewing the JPG file, not the embedded thumbnail in the RAW file....

Thanks for the info. That is interesting and good to know. I have often felt the images I shoot in RAW looked much better on my screen at home vs. the LCD even taking into account the obvious differences in the screens.

So, can one make any judgement on the sharpness of a RAW image file just from the LCD jpeg?
03-25-2010, 12:49 PM   #12
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QuoteOriginally posted by MSM Quote
So, can one make any judgement on the sharpness of a RAW image file just from the LCD jpeg?
On the K10D, I wouldn't put too much weight on what the camera's monitor shows. You're looking at a very low-resolution screen. I can spot critical focus on my K-7's screen because it's got full VGA resolution, but I still have to zoom in a whole bunch first.
03-26-2010, 08:38 AM   #13
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First off, your camera ONLY shoots RAW. When you select JPG, the camera takes the RAW data and pipes it into its on-board JPG processor to generate the JPG "image" to save to the card.

When you shoot RAW, the RAW "data" goes directly to the card and is not an image.

To generate an image, you use a RAW processor (software on your PC) which turns the data into a viewable image, much like the camera's JPG processor. The difference is that YOU have complete control over the image generation process. You can change the white balance, adjust the contrast/brightness/black point/etc....

So you can leave these decisions up to the camera's little processor (and hope it makes the right decisions since they are irreversible), or save the decisions for later where YOU have complete control over it.
03-26-2010, 10:03 AM   #14
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QuoteOriginally posted by Lowell Goudge Quote
I think the OP wants to know specifically what type of PP really demands RAW, you have made some good points in the past, such as sharpening, contrast and saturation beyond what is possible in camera, etc...
You're right, I didn't read the post carefully enough, and thought it was just a question of wondering why he couldn't see a difference.

In m experience, the things most likely to show you a noticeable advantage to shooting RAW are large-scale white balance changes (eg, the sort of thing I do virtually all the time in concert photography with strongly colored lights), exposure changes of a stop of more (which I do routinely because my camera maxes out at ISO 1600, so push processing is the only way to get faster shutter speeds), and also changes to the exposure *curve* - lightening just the shadows, or just the midtones - by similar amounts.

That much I would imagine would be true no matter what software you use. I also find I can get better results from NR and to a lesser extent (a much lesser extent, actually) from sharpening if I work from RAW, but that seems more likely to be software-dependent.

QuoteQuote:
I can also envision high key and low key portraits because there is too much risk of getting blocks of tones as opposed to smooth transitions when working at either extreme of the histogram in JPEG.
Yes. Also it's pretty common to have "hot spots" where detail is blown out even though the overall exposure is more or less where you want it, and you need to use highlight recovery tools - that's another area where RAW provides a definite advantage.

Basically, any time you need to use PP to "correct" less-than-ideal lighting, you're looking at a situation where RAW can give better results, although how much better depends on how much "correction" you are doing. I put it this way because all too often, one hears that one doesn't need to do much PP if one "gets it right" in camera. I'm talking about situations. where I might have perfectly captured the scene as it was, but I want it to look *better* - the way it would have looked had I been in control of the lighting.

This is the sort of thing I routinely do with curves or local contrast enhancement tools. I might have a face that is partially in the spotlight and also part of the background is in the spotlight, but I don't like where/how the transition from light to shadow on the face takes place, or I wish to darken that background, or lighten part of the performer not receiving direct light from the spotlight, etc.

In contrast to all this, in my landscapes I rarely do anything remotely like this. Maybe a lightening of a shadow, or rebalancing the distribution of values in a scene that exceeds the dynamic range of the camera, or backing off an overly enthusiastic AWB that tried too hard to remove the color of the lighting that I wanted to keep (setting WB to "flash" in PP is one of my favorite techniques here). But here I'm usually talking relatively small adjustments that I wouldn't say RAW provides a significant benefit. Maybe in terms of recovering detail in clouds in a scene that exceeds the dynamic range of the camera?
03-26-2010, 10:21 AM   #15
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QuoteOriginally posted by Lowell Goudge Quote
deliberate under exposing and trying to pull data out of the shadows is really one area where RAW is needed, but why not just up the ISO, after all this would be a better approach
K10D and k200D max out at 1600, making this a necessary technique pretty often on those cameras.

QuoteQuote:
and you get more resolution than pulling the data out of the shadows, with no impact on grain, Someone posted shots that proved this.
I'd like to see those. There's a lengthy discussion going on regarding this on dpr right now in which the consensus is that there is *not* going to be a noticeable difference most of the time. It's an entirely theoretical/mathematical discussion and could use illustration with images. *At best*, I could believe that raising ISO would be (slightly) more effective than a push in PP for ISO levels that are actually implemented via analog amplification in camera. But beyond 1600, that's actually rarely the case. Higher ISO's are usually achieved through simply digital pushing in the camera firmware (and the dpr discussion shows some histograms where you can *plainly* see this, since there are "holes" at all the odd values in the histogram just like you'd expect if you simplify multiplied values by two). if all you're doing is a digital push in camera, there is no reason to suspect the camera can multiply by two better than your RAW processing software.

And even in cases where you *are* getting analog amplification in camera, my feeling is that if you shoot RAW, it's pretty unlikely that you'd actually see a difference between that and a digital push in PP. That's because since RAW has more bits to deal with, those "holes" aren't ever going to visible by the time you actually convert to JPEG or some other 8-bit RGB format (and virtually all monitors and printer only deal with eight bits of data anyhow).

QuoteQuote:
as far as WB, I find that even under the worst lighting, JPEG has enough data to correct without any issues. at least using PSP X and higher, it is just one click of the mouse.
I've never used PSP X, but really have a hard time believing it could do *nearly* as good a job with JPEG as with RAW in the kind of lighting situations I deal with routinely. It's not a question of how "easy" it is - sure, an eyedropper or similar tool an be operated with just one click - but the range of colors you end up with when dealing with images shot as JPEG under very strongly colored lighting (like stage lighting) or if you've simply shot with a wildly wrong WB (like tungsten WB outdoors) just cannot compete with the range of colors you can get when working from RAW data. I find this mostly an issue in achieving pleasing skin tones.
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