f8lee Loc: New Mexico

I cannot tell from their website if PhotoPlus is a non-destructive editor (like LR is and PS is not): if you crop and rotate (say 30 degrees) and apply color temperature changes to your image in PhotoPlus, then a week later decide that your crop was too tight and you didn't want to rotate the image at all, can you go back to that file and undo those changes? If so, PhotoPlus would seem to be like LR. But Photoshop is not a non-destructive editor - when you perform those kinds of functions and save the image, the extraneous stuff is lost. Photoshop does not maintain the original file and keep an external list of instructions to perform hen that file is viewed or printed like LR does. That is the difference.

texashill Loc: Texas Hill Country

I am only a humble real estate agent who has learned some valuable knowledge on this forum. My skill and equipment is surely less than most posters here. I recently downloaded a free trial of corel aftershot 2 because of threads like this one. I must say after experimenting that I do better with jpeg. First of all, my raw shots must have the corners cropped out. I don't know why that it. Additionally, the raw shots have not been corrected for lens distortion. Yes, corel aftershot 2 has means to correct but I imagine that my camera jpeg output does a better job. Lastly, after I am done, I think the jpeg looks just as good or better.

My experimenting involved exterior shots. Perhaps if I had experimented with interior shots then I could have seen the increase in ability. But the need to crop the corners doesn't work will when photographing a kitchen while it is not much of a problem when photographing a house exterior.

f8lee Loc: New Mexico

This topic keeps getting raised, but this time I think the problem is the confusion as to where the limitations of JPEG versus raw files come into play.

We all know there are inherent limitations on the display side of things - the color gamut of both additive and subtractive color systems has limits. But that is not where the advantage of raw files comes into play - raw files simply offer far more latitude in the post-process editing that is done before the image is displayed or printed.

That is, and this has been mentioned by another responder here, if you have a scene with a wide dynamic range and shoot JPEG + raw, then go to edit both types of files, you will see that when you bring up the shadow details in the image the raw file's result will be far superior to the JPEG, only because the computer in the camera had to "decide" what to throw away in order to create the JPEG file. Likewise with highlights - with the raw file you will be able to pull far more detail out of a portion of the image that in the JPEG might have gone completely and irretrievably washed out.

Now, once you've processed the raw image, in order to print it you need to export it (since raw is not actually an image file per se) but the JPEG you get after post processing can be quite different than the one the in-camera computer produced.

And THAT is why it's better to shoot raw.

Apaflo Loc: Anchorage, Alaska

Your very cite explains demoisacing in terms of first a 2x2 matrix and then with 4x4 matrix, and states that other algorithms can extract even more information.

This URL explains it using examples that have 3x3, 4x4 and 5x5 matrices.

http://www.siliconimaging.com/RGB%20Bayer.htm

Here's a URL using 5x5 for examples,

http://sites.google.com/site/chklin/demosaic

Here is a very detailed paper using a 5x5 matrix,

http://research.microsoft.com/pubs/102068/Demosaicing_ICASSP04.pdf

Every technical paper that exists on Bayer demosaicing shows how it is done using a matrix.


It does not compromise resolution, but it does affect acutance or sharpness. The spatial transition from one color tone to another cannot be less than the size of the matrix. That is exactly why sharpening is beneficial to any image from a Bayer style camera.

selmslie Loc: Fernandina Beach, FL, USA

That's pretty much it, in a nutshell - the first and most important reason to shoot raw.

The other is that editing a JPEG is like adding paint to a piece of furniture. If you don't sand it back down to the raw (pun intended) wood its going to eventually end up looking lumpy and bad.

tomeveritt Loc: Fla. + Ga,NY,Va,Md,SC

busmaster2 Loc: College Point NY

Ok so if one were to process raw to tiff is there any advantage?

4ellen4 Loc: GTA--Ontario

So far I have mostly shot in the jpeg format, that mainly being since I carry my Nikon P500 with me all the time and it shoots jpeg only.

If you shoot on the raw format, yes you certainly do get a lot better image with more details. After doing your editing of the raw image convert it to a tiff or even png image so that you do not lose a lot of the image detail as you would if you converted to a jpg--hope that helps

busmaster2 Loc: College Point NY

Yes thanks

camerapapi Loc: Miami, Fl.

Let me start by saying that I use Capture NX2 for my RAW files. It is a software designed by Nikon and put together by Nik. It is in my opinion the best software to read and edit Nikon files and the majority of in camera settings are honored by the software.
When I started to use digital in 2002 I did not attend a simple workshop where the instructor insisted in using RAW files and a wide color space. As time went by I began to question if it was absolutely necessary to shoot everything RAW and began to compare files. RAR offers great flexibility during editing but JPEG also can be manipulated to make it a better file. Saving a JPEG to TIFF makes it lossless and working with a copy preserves the original. I have had no issues using JPEG files and some of my best shots for enlargements have come from JPEGs.
It is true that a RAW file has many more megapixels than a JPEG and it is also true that it is better to work with 12 bits and a large color space than working with 8 bits and sRGB.
Sooner or later that RAW file, only read by special software and that wide color space that cannot be seen very well by the monitor will need conversion from 12 to 8 bits and from the wide color space to sRGB. I think that nobody has to be a genius to understand that when that is done something has to give. I have not been able to understand what it is but making something big to something smaller makes me believe that in that transformation many things could happen. By the way, the human eye cannot see trillions of colors and we cannot see either all of the colors within the sRGB color space.
I like JPEG images and I have been very successful with them. I also use RAW.

Delderby Loc: Derby UK

Agreed. :-)

selmslie Loc: Fernandina Beach, FL, USA

A basic understanding of the process is covered well in the http://www.cambridgeincolour.com/tutorials/camera-sensors.htm link. Once you grasp the concept of the 2x2 array, the rest is merely refinement and does little to clarify the process.

Some of the statements made in the links you cite are speculative - processes that might be used. We don't really know what methods are actually used. And your second link is over a decade out of date. There is no way of knowing if it describes anything that is the current state-of-the-art.

Since the OP is really starting from the beginning, it is probably best not to overwhelm him with too much technical detail.

Apaflo Loc: Anchorage, Alaska

It is more likely to be precise, but not accurate.

The fewer levels that exist within a 1 fstop increment, the less accurate the value is likely to be (the larger the quantization error). But the precision will stay the same.


And the specific problem is quantization distortion, which specifically is the error causing values that are not accurate. They are precise though.


Or more likely not. The precision of 16 bits is maintained during the various calculation, but the significance is the higher accuracy. That is maintained until the data is converted to 8 bit, at which point both precision and accuracy are reduced.


It is no longer accurate, and you cannot make it more accurate.

It really is necessary to understand what accuracy is as opposed to what precision is.

selmslie Loc: Fernandina Beach, FL, USA

Yes, you need to see: http://en.wikipedia.org/wiki/Accuracy_and_precision

As for a color image, how would you determine what is accurate? Are we looking for an accurate representation of reality? Does it become more accurate when it more closely resembles what you saw? What you thought you saw? What you want others to see? Or is it what the unedited raw file produces when you convert it without editing input?

If the raw image were accurate you would not need to edit it at all.

canon Lee

Here we go again. Same question, different day. LOL simply put= RAW is DATA information that creates a JPEG (JPEG IS THE PICTURE) . You have the choice to create your own JPEG using Raw data in post production, OR you can have the camera do it for you so that the output of your camera is a JPEG.
Here is another analogy, You want to make a cake. RAW is the recipe, JPEG is the cake. Hope this helps.
The recipe contains all of the complete ingredients needed, where shooting in JPEG, contains less ingredients, omitting or changing the quantities.