RAW and JPEG
-
Okay I have never had a digital camera that allows storing RAW image; but lately I've been eying on the Canon PowerShot G9, which can store RAW. I have some questions. 1.) Most camera allow you to set the compression level (ie, normal, fine, SuperFine). Does that mean that those regular camera compresses the image from the original image (assuming that's RAW) to JPEG right away, whereas on the camera that allows RAW stores the original image without any compression? 2.) I assume that once you have that RAW file, you would convert it to JPEG using software like photoshop? 3.) From you experience, which one produces better quality JPEG image? Software like photoshop? Or Camera's digital processor like Canon's DIGIC III? Thanks
-
Okay I have never had a digital camera that allows storing RAW image; but lately I've been eying on the Canon PowerShot G9, which can store RAW. I have some questions. 1.) Most camera allow you to set the compression level (ie, normal, fine, SuperFine). Does that mean that those regular camera compresses the image from the original image (assuming that's RAW) to JPEG right away, whereas on the camera that allows RAW stores the original image without any compression? 2.) I assume that once you have that RAW file, you would convert it to JPEG using software like photoshop? 3.) From you experience, which one produces better quality JPEG image? Software like photoshop? Or Camera's digital processor like Canon's DIGIC III? Thanks
Link2006 wrote:
Does that mean that those regular camera compresses the image from the original image (assuming that's RAW) to JPEG right away, whereas on the camera that allows RAW stores the original image without any compression?
The original image is data straight off the sensor, you can consider it an image map or bitmap. While sensors were 8bit like your monitor you could use Tiff compression to provide lossless compression. Many of the early high end cameras had TIFF compression as the best source. But times change and technology increases, and to increase the "easy" image quality that we have come to associate with digital cameras, sensors have continued to increase in capability. I don't know the year, but the first 10bit sensors created a quandary, yes it was easier to get a quality image from a slightly under or overexposed image and still get 8 quality bits for an image.... but that takes the control away and makes it automatic. What if you wanted to self-tune that image display to get your preferred contrast and brightness and color. RAW was the answer. RAW takes images in 10,12,14 bits per color and compresses them using lossless methods. With advent of 48bit color screens for HDMI signals, we can now have 3 color 16bit per color displays, though they are still hard to find. But a good quality photoshop software can extract any 8 bits, or compress the signal to a minor form of High Dynamic Range photography. So again RAW allows you to extract the full information of the original sensor image to form any image you want to get out of. RAW is often referred to as a "digital negative" offering you the full range of light collected by the sensor. Just as negatives allow photographers to "reexpose" a new image from the negative RAW allows you to extract many images of different contrast and brightness and color from the original exposure information.
Link2006 wrote:
I assume that once you have that RAW file, you would convert it to JPEG using software like photoshop?
yes, if you want to send it to someone else. I do all my prints and image processing directly off RAW, it never goes through JPEG any more. But it took me a while to get all my tools to support RAW formats. I only convert to jpeg to send to someone else or upload for someone to look at. When I enter an image in the state fair, it is printed directly off the RAW image.
Link
-
Okay I have never had a digital camera that allows storing RAW image; but lately I've been eying on the Canon PowerShot G9, which can store RAW. I have some questions. 1.) Most camera allow you to set the compression level (ie, normal, fine, SuperFine). Does that mean that those regular camera compresses the image from the original image (assuming that's RAW) to JPEG right away, whereas on the camera that allows RAW stores the original image without any compression? 2.) I assume that once you have that RAW file, you would convert it to JPEG using software like photoshop? 3.) From you experience, which one produces better quality JPEG image? Software like photoshop? Or Camera's digital processor like Canon's DIGIC III? Thanks
Link2006 wrote:
1.) Most camera allow you to set the compression level (ie, normal, fine, SuperFine). Does that mean that those regular camera compresses the image from the original image (assuming that's RAW) to JPEG right away, whereas on the camera that allows RAW stores the original image without any compression?
Yes any time you have a JPG it is compressed to some level, even the highest quality JPG setting has some compression. RAW files are direct pixel by pixel values no compression they are basically a digital negative and you can post process them +/- 3 or more stops (almost any thing short of re-shooting the picture very cool:cool:) Use any app to process RAW is like digital Darkroom. Photoshop ect also allows you to go beyond to manipulate the image.
Link2006 wrote:
2.) I assume that once you have that RAW file, you would convert it to JPEG using software like photoshop?
YES look at products like LightRoom and RAWShooter you will want to adjust the light levels color ect then save as JPG most will never change the original RAW file.
Link2006 wrote:
3.) From you experience, which one produces better quality JPEG image? Software like photoshop? Or Camera's digital processor like Canon's DIGIC III?
It is up to what you want to do A) Correct the image light, dark, color, white balance ect then Lightroom, RawShooter ect. B) After correcting the image if you also want to change it add someone to the picture combine several elements of other pictures (make it diffrent than what was shot) use Photoshop ect Note: Photoshop has plugins that allow you to do both correction and manipulation. Once you get into it you will have alot of fun creating some of the best photos you have seen.:cool: I shoot both depending on what I am doing snap shots JPG only and RAW for photographs. Dan
-
Okay I have never had a digital camera that allows storing RAW image; but lately I've been eying on the Canon PowerShot G9, which can store RAW. I have some questions. 1.) Most camera allow you to set the compression level (ie, normal, fine, SuperFine). Does that mean that those regular camera compresses the image from the original image (assuming that's RAW) to JPEG right away, whereas on the camera that allows RAW stores the original image without any compression? 2.) I assume that once you have that RAW file, you would convert it to JPEG using software like photoshop? 3.) From you experience, which one produces better quality JPEG image? Software like photoshop? Or Camera's digital processor like Canon's DIGIC III? Thanks
1. Correct.
The JPEGs you get from a compact camera are post processed images. The camera's internal processing chip does all of the work for you. Its does the colour correction, sharpening, tonal adjustments and of course compression. The JPEG image you see are almost never the same image that has been 'truely' captured by the sensor.2. Correct
The beauty of the RAW file (which is basically a dump of the camera's censor), is that you have total control over what is applied to your image.3. Hmmmm.
Depends on the experience of the person processing the RAW image. I use a Canon 350d (rebel xt). I am a novice, so a lot of the time, the camera's automated mode produces better or similar quality results than several hours of my Photoshop tweaking. But occasionally....just occasionally, I get a masterpiece from my RAW image that most automated cameras would just would not have post processed properly. I shoot mostly in RAW now, only switching to JPEG if I really need to conserve space.
I Dream of Absolute Zero
-
Link2006 wrote:
Does that mean that those regular camera compresses the image from the original image (assuming that's RAW) to JPEG right away, whereas on the camera that allows RAW stores the original image without any compression?
The original image is data straight off the sensor, you can consider it an image map or bitmap. While sensors were 8bit like your monitor you could use Tiff compression to provide lossless compression. Many of the early high end cameras had TIFF compression as the best source. But times change and technology increases, and to increase the "easy" image quality that we have come to associate with digital cameras, sensors have continued to increase in capability. I don't know the year, but the first 10bit sensors created a quandary, yes it was easier to get a quality image from a slightly under or overexposed image and still get 8 quality bits for an image.... but that takes the control away and makes it automatic. What if you wanted to self-tune that image display to get your preferred contrast and brightness and color. RAW was the answer. RAW takes images in 10,12,14 bits per color and compresses them using lossless methods. With advent of 48bit color screens for HDMI signals, we can now have 3 color 16bit per color displays, though they are still hard to find. But a good quality photoshop software can extract any 8 bits, or compress the signal to a minor form of High Dynamic Range photography. So again RAW allows you to extract the full information of the original sensor image to form any image you want to get out of. RAW is often referred to as a "digital negative" offering you the full range of light collected by the sensor. Just as negatives allow photographers to "reexpose" a new image from the negative RAW allows you to extract many images of different contrast and brightness and color from the original exposure information.
Link2006 wrote:
I assume that once you have that RAW file, you would convert it to JPEG using software like photoshop?
yes, if you want to send it to someone else. I do all my prints and image processing directly off RAW, it never goes through JPEG any more. But it took me a while to get all my tools to support RAW formats. I only convert to jpeg to send to someone else or upload for someone to look at. When I enter an image in the state fair, it is printed directly off the RAW image.
Link
El Corazon wrote:
I do all my prints and image processing directly off RAW, it never goes through JPEG any more. But it took me a while to get all my tools to support RAW formats. I only convert to jpeg to send to someone else or upload for someone to look at. When I enter an image in the state fair, it is printed directly off the RAW image.
Okay, so if a RAW file is just a direct dump from the sensors, it's mostly un-tweaked. If you use Photoshop to do all the color corrections, and tweaking, etc, shouldn't it produce a better image? But from what I understand, once you altered the RAW file, you can not save it to the original RAW file anymore.
-
El Corazon wrote:
I do all my prints and image processing directly off RAW, it never goes through JPEG any more. But it took me a while to get all my tools to support RAW formats. I only convert to jpeg to send to someone else or upload for someone to look at. When I enter an image in the state fair, it is printed directly off the RAW image.
Okay, so if a RAW file is just a direct dump from the sensors, it's mostly un-tweaked. If you use Photoshop to do all the color corrections, and tweaking, etc, shouldn't it produce a better image? But from what I understand, once you altered the RAW file, you can not save it to the original RAW file anymore.
Link2006 wrote:
But from what I understand, once you altered the RAW file, you can not save it to the original RAW file anymore.
I don't use photoshop, usually, my digital studio saves the parameters of "choice" in another file so the RAW remains intact, I can go back and change those values anytime. If I want to actually save the full exposure, I save in EXR which supports 16 and 32bit per color values.
_________________________ Asu no koto o ieba, tenjo de nezumi ga warau. Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb)
-
El Corazon wrote:
I do all my prints and image processing directly off RAW, it never goes through JPEG any more. But it took me a while to get all my tools to support RAW formats. I only convert to jpeg to send to someone else or upload for someone to look at. When I enter an image in the state fair, it is printed directly off the RAW image.
Okay, so if a RAW file is just a direct dump from the sensors, it's mostly un-tweaked. If you use Photoshop to do all the color corrections, and tweaking, etc, shouldn't it produce a better image? But from what I understand, once you altered the RAW file, you can not save it to the original RAW file anymore.
-
RAW simply means that is has not been compressed.
Visit http://www.notreadytogiveup.com/[^] and do something special today.
Trollslayer wrote:
RAW simply means that is has not been compressed.
has not been lossy compressed. Most RAW file formats use a type of lossless compression, only a few store the image without any compression at all.
_________________________ Asu no koto o ieba, tenjo de nezumi ga warau. Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb)
-
Okay I have never had a digital camera that allows storing RAW image; but lately I've been eying on the Canon PowerShot G9, which can store RAW. I have some questions. 1.) Most camera allow you to set the compression level (ie, normal, fine, SuperFine). Does that mean that those regular camera compresses the image from the original image (assuming that's RAW) to JPEG right away, whereas on the camera that allows RAW stores the original image without any compression? 2.) I assume that once you have that RAW file, you would convert it to JPEG using software like photoshop? 3.) From you experience, which one produces better quality JPEG image? Software like photoshop? Or Camera's digital processor like Canon's DIGIC III? Thanks
If you want to play with your images and have maximum quality, you should use the RAW files. Photoshop does not support directly RAW files, they have to go through an importer like camera raw. Also Raw files are not just uncompressed images, they are a dump of the sensors. Usually sensors do not have RGB triplets for each locations, so post processing has to be done to generate a full RGB image. Not even talking about compression yet. Also raw values are floating points, not integers. The quality of the algorithms used for this step can make quite a difference in the look of the image. For manual and automated Raw processing, you should try Optics Pro at www.dxo.com. They also have an interesting product called FilmPack which processes images to give them the look they would have, had they been shot with a particular camera, or a particular film.
-
If you want to play with your images and have maximum quality, you should use the RAW files. Photoshop does not support directly RAW files, they have to go through an importer like camera raw. Also Raw files are not just uncompressed images, they are a dump of the sensors. Usually sensors do not have RGB triplets for each locations, so post processing has to be done to generate a full RGB image. Not even talking about compression yet. Also raw values are floating points, not integers. The quality of the algorithms used for this step can make quite a difference in the look of the image. For manual and automated Raw processing, you should try Optics Pro at www.dxo.com. They also have an interesting product called FilmPack which processes images to give them the look they would have, had they been shot with a particular camera, or a particular film.
Pierre Leclercq wrote:
Photoshop does not support directly RAW files, they have to go through an importer like camera raw.
Photoshop Camera Raw plug-in works perfectly and been updated to support more cameras, and is available as part of Adobe Photoshop CS3. jhaga
Recommended books: Nish's C++/CLI in Action Vavilala's AJAX for ASP.NET The Career Programmer Buy and sell your computer equipment at Half.com
-
El Corazon wrote:
I do all my prints and image processing directly off RAW, it never goes through JPEG any more. But it took me a while to get all my tools to support RAW formats. I only convert to jpeg to send to someone else or upload for someone to look at. When I enter an image in the state fair, it is printed directly off the RAW image.
Okay, so if a RAW file is just a direct dump from the sensors, it's mostly un-tweaked. If you use Photoshop to do all the color corrections, and tweaking, etc, shouldn't it produce a better image? But from what I understand, once you altered the RAW file, you can not save it to the original RAW file anymore.
Link2006 wrote:
Okay, so if a RAW file is just a direct dump from the sensors, it's mostly un-tweaked. If you use Photoshop to do all the color corrections, and tweaking, etc, shouldn't it produce a better image?
You can. You can also produce a worse image depending on your level of skill.
Link2006 wrote:
But from what I understand, once you altered the RAW file, you can not save it to the original RAW file anymore.
It's like any other file. You can modify it and save over the original (in which case it's gone) or you can save it to a new name (in which case you have both versions).
Otherwise [Microsoft is] toast in the long term no matter how much money they've got. They would be already if the Linux community didn't have it's head so firmly up it's own command line buffer that it looks like taking 15 years to find the desktop. -- Matthew Faithfull
-
Link2006 wrote:
Does that mean that those regular camera compresses the image from the original image (assuming that's RAW) to JPEG right away, whereas on the camera that allows RAW stores the original image without any compression?
The original image is data straight off the sensor, you can consider it an image map or bitmap. While sensors were 8bit like your monitor you could use Tiff compression to provide lossless compression. Many of the early high end cameras had TIFF compression as the best source. But times change and technology increases, and to increase the "easy" image quality that we have come to associate with digital cameras, sensors have continued to increase in capability. I don't know the year, but the first 10bit sensors created a quandary, yes it was easier to get a quality image from a slightly under or overexposed image and still get 8 quality bits for an image.... but that takes the control away and makes it automatic. What if you wanted to self-tune that image display to get your preferred contrast and brightness and color. RAW was the answer. RAW takes images in 10,12,14 bits per color and compresses them using lossless methods. With advent of 48bit color screens for HDMI signals, we can now have 3 color 16bit per color displays, though they are still hard to find. But a good quality photoshop software can extract any 8 bits, or compress the signal to a minor form of High Dynamic Range photography. So again RAW allows you to extract the full information of the original sensor image to form any image you want to get out of. RAW is often referred to as a "digital negative" offering you the full range of light collected by the sensor. Just as negatives allow photographers to "reexpose" a new image from the negative RAW allows you to extract many images of different contrast and brightness and color from the original exposure information.
Link2006 wrote:
I assume that once you have that RAW file, you would convert it to JPEG using software like photoshop?
yes, if you want to send it to someone else. I do all my prints and image processing directly off RAW, it never goes through JPEG any more. But it took me a while to get all my tools to support RAW formats. I only convert to jpeg to send to someone else or upload for someone to look at. When I enter an image in the state fair, it is printed directly off the RAW image.
Link
I have a question for you: a while back I had some free time and downloaded photomatix HDR software to experiment with it. I'm trying to solve a problem I have living in this area: it's cloudy a *lot* of the time. Here it's technically a tropical rainforest although a cold one, the forest has huge trees with lots of moss everywhere, ferns etc. It's extremely beautiful to look at, rich colours, gloomy, mossy, often rain drops all over. Problem is that I can't for the life of me get a picture that reflects what I see. The closest I can come is to shoot the photo in "Vivid" mode on my canon which replicates vivid slide film, then post process it adjusting curves to make it more contrasty. I thought HDR techniques would help but after experimenting with it (even trying 6 exposures and maxing out all the settings [^]) I'm getting the feeling it works best for the opposite scenario, a high contrasty lit scene. My experiment looks...well weird I guess, nothing like I see with my eyes. Am I right in that HDR won't help at all with flat contrast scenes?
When everyone is a hero no one is a hero.
-
I have a question for you: a while back I had some free time and downloaded photomatix HDR software to experiment with it. I'm trying to solve a problem I have living in this area: it's cloudy a *lot* of the time. Here it's technically a tropical rainforest although a cold one, the forest has huge trees with lots of moss everywhere, ferns etc. It's extremely beautiful to look at, rich colours, gloomy, mossy, often rain drops all over. Problem is that I can't for the life of me get a picture that reflects what I see. The closest I can come is to shoot the photo in "Vivid" mode on my canon which replicates vivid slide film, then post process it adjusting curves to make it more contrasty. I thought HDR techniques would help but after experimenting with it (even trying 6 exposures and maxing out all the settings [^]) I'm getting the feeling it works best for the opposite scenario, a high contrasty lit scene. My experiment looks...well weird I guess, nothing like I see with my eyes. Am I right in that HDR won't help at all with flat contrast scenes?
When everyone is a hero no one is a hero.
Try pushing the color temp cloud cover and shade should be higher
-
I have a question for you: a while back I had some free time and downloaded photomatix HDR software to experiment with it. I'm trying to solve a problem I have living in this area: it's cloudy a *lot* of the time. Here it's technically a tropical rainforest although a cold one, the forest has huge trees with lots of moss everywhere, ferns etc. It's extremely beautiful to look at, rich colours, gloomy, mossy, often rain drops all over. Problem is that I can't for the life of me get a picture that reflects what I see. The closest I can come is to shoot the photo in "Vivid" mode on my canon which replicates vivid slide film, then post process it adjusting curves to make it more contrasty. I thought HDR techniques would help but after experimenting with it (even trying 6 exposures and maxing out all the settings [^]) I'm getting the feeling it works best for the opposite scenario, a high contrasty lit scene. My experiment looks...well weird I guess, nothing like I see with my eyes. Am I right in that HDR won't help at all with flat contrast scenes?
When everyone is a hero no one is a hero.
John C wrote:
I thought HDR techniques would help but after experimenting with it (even trying 6 exposures and maxing out all the settings [^]) I'm getting the feeling it works best for the opposite scenario, a high contrasty lit scene. My experiment looks...well weird I guess, nothing like I see with my eyes.
HDR technically will only help a little for the problem you are seeing. HDR is a high-contrast scene where light is extremely dim in places (shadows) to fully illuminated by a light. Normally a camera will pick up the light that is brightest in higher amounts than the dim reflections from the shadows. This kind of makes sense. The camera gathers enough light to reach a certain histogram brightness and then shuts off the lens and processes the sensor data. Now if you step back to that concept, look at your scene again. If you can, do a spot exposure of your scene at the darkest spot, evaluate the exposure settings, do the same for the lightest spot. If you want to do HDR of a natural scene... expose only between those two numbers in powers of two of shutter speed (i.e. 1/30th 1/60th, etc.). Now blend them together with photomatix. the results are much more pleasing.
_________________________ Asu no koto o ieba, tenjo de nezumi ga warau. Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb)
-
John C wrote:
I thought HDR techniques would help but after experimenting with it (even trying 6 exposures and maxing out all the settings [^]) I'm getting the feeling it works best for the opposite scenario, a high contrasty lit scene. My experiment looks...well weird I guess, nothing like I see with my eyes.
HDR technically will only help a little for the problem you are seeing. HDR is a high-contrast scene where light is extremely dim in places (shadows) to fully illuminated by a light. Normally a camera will pick up the light that is brightest in higher amounts than the dim reflections from the shadows. This kind of makes sense. The camera gathers enough light to reach a certain histogram brightness and then shuts off the lens and processes the sensor data. Now if you step back to that concept, look at your scene again. If you can, do a spot exposure of your scene at the darkest spot, evaluate the exposure settings, do the same for the lightest spot. If you want to do HDR of a natural scene... expose only between those two numbers in powers of two of shutter speed (i.e. 1/30th 1/60th, etc.). Now blend them together with photomatix. the results are much more pleasing.
_________________________ Asu no koto o ieba, tenjo de nezumi ga warau. Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb)
-
Cool, thanks, that makes a lot of sense. I guess I'm looking for some other technique entirely to deal with the lighting here. Cheers.
When everyone is a hero no one is a hero.
John C wrote:
I guess I'm looking for some other technique entirely to deal with the lighting here.
maybe... but have you tried just increasing the sharpness, increasing the shutter, raising the F-stop? There are many things to try in taking a picture.
_________________________ Asu no koto o ieba, tenjo de nezumi ga warau. Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb)
-
John C wrote:
I guess I'm looking for some other technique entirely to deal with the lighting here.
maybe... but have you tried just increasing the sharpness, increasing the shutter, raising the F-stop? There are many things to try in taking a picture.
_________________________ Asu no koto o ieba, tenjo de nezumi ga warau. Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb)