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Alex D80
08-10-2007, 12:03 AM
Why would I shoot RAW vs Normal or Fine JPG? What are the benefits. I noticed the pictures are HUGE compare to JPG. Also, need a software to convert them to then print them/email them/save them for keeps.

I was shooting RAW+Normal JPG and I didn't notice much of color change. I am reading the RAM images with Lightroom v1.1 and Elements v5.0.

fionndruinne
08-10-2007, 12:11 AM
You would want to use raw when you know you will be doing some PP to the photo, because it saves more data. For something like Lightroom's highlight recovery tool, a raw image will produce more effective results than a jpeg, which clips off the data for those highlights at a lossier rate. I don't use raw consistently, but when I find a great shot, I'll usually take a few photos in raw as well as some in jpeg, in case I want to do any heavy editing.

K1W1
08-10-2007, 01:35 AM
Most RAW editors are non destructive no matter what changes you apply the original data is saved and you can go backwards if you need to. Jpeg editing is destructive and the changes you apply can often never be fully undone.
You can always save untouched back up copies of Jpegs if you want but that involves a disciplined backup routine.
As mentioned even a Jpeg fine image is compressed so data is lost right at the time the shutter is pressed. Once that data has gone it's gone forever but
really whether you shoot RAW or Jpeg is up to you. Whatever you are most comfortable is the correct procedure in your case.

aparmley
08-10-2007, 06:26 AM
Sorry Fionndruinne, I'm going to use your post to make a point, I do it with all do respect:


You would want to use raw when you know you will be doing some PP to the photo...

Every photo taken with a DSLR has some PP (Post Processing) done to it. Think about it, if you shoot JPEG, your camera has to convert the RAW image it captures into a JPEG so its going to processs the photo with the parameters the user has selected in camera post capture. But you were exactly right in saying:


because it saves more data.

Alex. I recommend you look into purchasing one or both of the following if you are really interested in RAW:

Real World RAW by Bruce Frasier (sp?)

and

The Art of RAW conversion by by Juergen Gulbins (Author), Uwe Steinmueller (Author) ( I don't own this book but its one of the next ones I buy.

The First book really goes into great detail about why a user would select RAW over any in-camera JPEG conversions.


Jpeg editing is destructive and the changes you apply can often never be fully undone.


Not true any more. With newer RAW/JPEG editing programs coming out, like Adobe Lightroom and aperture they both offer non-destructive image editing for both RAW and jpegs.

erichlund
08-10-2007, 08:27 AM
Sorry Fionndruinne, I'm going to use your post to make a point, I do it with all do respect:



Every photo taken with a DSLR has some PP (Post Processing) done to it. Think about it, if you shoot JPEG, your camera has to convert the RAW image it captures into a JPEG so its going to processs the photo with the parameters the user has selected in camera post capture. But you were exactly right in saying:

This one's a bit unfair. He was indicating the person. Of course the camera does post processing. It even does post processing to a RAW. After all, you have to convert voltages to numbers, if nothing else. When we talk about post processing, we are talking about manipulating the image that is on the card.



Alex. I recommend you look into purchasing one or both of the following if you are really interested in RAW:

Real World RAW by Bruce Frasier (sp?)

and

The Art of RAW conversion by by Juergen Gulbins (Author), Uwe Steinmueller (Author) ( I don't own this book but its one of the next ones I buy.

The First book really goes into great detail about why a user would select RAW over any in-camera JPEG conversions.



Not true any more. With newer RAW/JPEG editing programs coming out, like Adobe Lightroom and aperture they both offer non-destructive image editing for both RAW and jpegs.

How does Adobe Lightroom do non-destructive image editing that you can then transfer to another editor. The jpg would eventually have to be saved in its standard format, and that image is non-reversible. I can see how, if you keep the image in Lightroom, the application could only make the changes to a temporary copy of the original for display, but to use the photo with the changes in another editor, the temporary with the changes has to be saved, and that file has no go back information. If Lightroom is keeping track of changes to every pixel, I feel sorry for your hard drive. That's a lot of data.

XaiLo
08-10-2007, 09:57 AM
When preforming jpeg and raw adjustments or editing (the following numbers are for illustration purposes only) let's look at the possible adjustments as a sliding scale "0" equals white, the halfway point is medium gray, and last number equal black.

A sensor only captures grayscale value.

JPEG Scale 0''''5''''10

Raw Scale 0'''''''''10'''''''''20''''25''''30'''''''''40'''' '''''10

output devices convert those values into color.

for example in an RGB color space (blue)

florescent green or lime has a RGB value of:

R:153
G:255
B:51

which means:

The red channel has a grayscale value of 153
The green channel has a grayscale value of 255
The blue channel has a grayscale value of 51

As can be seen in the JPEG example there are only 4 possible values between white (0) and medium gray (5); in contrast raw has 23 possible values between white (0) and medium gray (25). Raw will give you a more precise value of gray.

Second thing is jpeg compression it's a lossy compression, which as it sound looses information by it's very nature. Depending on the photo that can equate to usable, bearable or trashable:)

If I'm just taking pictures for the sake of taking pictures I'll shoot JPEG fine anything else I shoot raw plus basic. I took some JPEG portrait pictures of a friend that I attempted to edit the picture and due to the skin color, tonal changes, and highlights were no longer possible because the required tonal information and possibilities were gone. After that I learned to appreciate raw files. :) hth

coldrain
08-10-2007, 09:57 AM
There is NO difference in shooting in RAW and then just do a standard conversion to a photo (JPEG, BMP, TIFF, PNG, whatever format takes your fancy), and shooting in JPEG.

JPEG has 8 bits per colour channel (red, green, blue) which is enough to show any photo with good colour, contrast and dynamic range.
So, of course you wil not see much of a difference between RAW and JPEG.

Why then RAW? Because, RAW gives you more room for changes to the photo.
RAW stores pixel info in 12 bits. This gives a lot smaller steps between black and white compared to JPEG: 4095 steps compared to 255 steps.
So, when you for instance need to lighten or darken the photo a lot, in JPEG you may get to see the steps. In RAW you have much smaller steps, and so, when changing the image you have a lot more freedom to do so without it showing clearly. The smaller steps also are of big value when changing/correcting white balance.

So... if you never post process photos in a big way, RAW is not for you. If you do want to explore post processing, RAW can be worth it.

**edit:
JPEG has 256 "grey" levels, 0 being black, 256 being white. 50% gray being in the middle (127/128).

In RAW it is more complicated, while there are 2048 grey levels, 50% is not in the middle.
RAW has more values in the light than it has in the dark part of the spectrum, because of the way the light diodes measure light. Any conversion to any image format or format to represent the image into the screen converts those RAW levels into linear levels like you have with JPEG, which will make you "lose" part of the info, even in 16bit formats like 16 bit tiff.

swgod98
08-10-2007, 12:42 PM
Actually, I've noticed that RAW keeps more details compared to JPG (on my D80). And that was on RAW+FINE. Different camera's may have different conversion routines, but in my experience, shooting in RAW then converting to JPG in PS gives me a better image than shooting in JPG.

LR Max
08-10-2007, 01:49 PM
In the first step, I tested FINE vs. NORMAL. I saw no difference so I started shooting in NORMAL. BASIC just seemed a little too diminished for me. (D70s)

I mainly shoot in LRG NORMAL since the files are easy to work with, relatively small, and don't kill my hard drive. If you are good about setting up the camera then you'll only post process it a hare. JPG is fine.

If I have a situation where I question my ability to capture the image accurately, then I'll shoot RAW. I also shoot RAW for work, but only because it was requested of me.

K1W1
08-10-2007, 04:25 PM
This info is for the D50.
According to Thom Hogan the D50 fine jpegs are approx 4:1 compression and Normal is 8:1. His suggestion is that anything under 10:1 is acceptable in most common photo scenes.

TNB
08-10-2007, 06:07 PM
I shot in RAW most of the time, especially since publishers may require a RAW or .tiff file. Just a little something else to think about since "they" may want to do their own post processing.

aparmley
08-11-2007, 09:34 AM
So I think the message is starting to take shape for you Alex. The message is: "Its personal preference." Thats all it is.

e_dawg
08-11-2007, 10:07 AM
I always shoot in RAW + JPEG basic if possible. RAW offers me "insurance" in case I mess up the exposure or focus of the shot, as there is more data to work with for post-processing with RAW files. I can't tell you how many times I have successfully "saved" a pic that turned out to be a gem because I just captured the right moment or expression. The exposure or focus might have been off, ruining the shot. But being able to save those gems is priceless to me.

If the JPEG looks great straight out of the camera, then you don't even need to do anything. But the RAW file is there with its 16-bit interpolation of 12-bit data (or 10-bit for some P&S and 14-bit for some dSLR) to save your a*s when you need it.

Alex D80
08-11-2007, 06:15 PM
Thanks for all the responses. I noticed that the RAW image was a little simpler to to editing to it in Lightroom. I guess RAW is exactly what the sensor reads and justs saves it like that. I noticed it also more accurate in color than the JPG-NORMAL.

I guess I might need to upgrade to 4GB card if I continue to mess with RAW+JPG-NORMAL so I can see what each picture is. I guess if I am going to be printing the image to a poster or so, then use the RAW. If I am just using it to viewing, then JPG will work. No need to be opening each RAW image and saving it to JPG and let Lightroom do the compression.

Once again, thanks for all your responses. I took in a little from each of you and that is what I am going with. :)

Alex D80
08-11-2007, 06:16 PM
I always shoot in RAW + JPEG basic if possible. RAW offers me "insurance" in case I mess up the exposure or focus of the shot, as there is more data to work with for post-processing with RAW files. I can't tell you how many times I have successfully "saved" a pic that turned out to be a gem because I just captured the right moment or expression. The exposure or focus might have been off, ruining the shot. But being able to save those gems is priceless to me.


How do you fix an out of focus RAW image? Lightroom? Elements?

Rooz
08-11-2007, 07:06 PM
How do you fix an out of focus RAW image? Lightroom? Elements?

yeah not sure what edawg is referring to here. i think that was a typo. you can;t restore out of focus pics regardless of file format.

e_dawg
08-12-2007, 03:15 AM
I don't know how that could be misinterpreted as a typo, since I "typoed" it twice.

Anyways, you can restore out of focus and motion blurred images to a limited extent using deconvolvers that (IIRC) invoke FFT and sinc functions to reverse point spread and perform interpolation. Two of the more popular utilities for this are: Unshake (freeware) and Focus Magic.

Depending on the situation, deconvolution is also a superior alternative for increasing image sharpness than USM. e.g., from soft lenses (used it to "fix" the softness of the Canon S3 lens sometimes). It's different from traditional USM... lens blur and Smart Sharpen with PS are closer than traditional USM, but not the same either AFAIK.

I use Unshake at the end of my workflow as a substitute for USM. You have to decide which one to use, depending on the situation, as they are both very destructive actions. Another reason to use it at the end is that Unshake only outputs to JPEG and cannot be used as a PS plug-in.

Focus Magic is available as a PS plug-in, but I think it's missing some features compared to the stand-alone program. The stand-alone program is not compatible with Vista yet, btw.

Rooz
08-12-2007, 03:25 AM
can you give us some before and after shots using that software. i'd like to see how effective it can be.

coldrain
08-12-2007, 03:51 AM
I have been fighting with FocusMagic a few times myself. The results have never been acceptable to me. While you can get some slight out of focus areas to look a bit sharper, along comes a huge load of artifacting.

And this has nothing to do with RAW vs. JPEG anyway, since these programs do not use RAW data, just any image. So also on a JPEG.

e_dawg
08-12-2007, 10:26 AM
I have been fighting with FocusMagic a few times myself. The results have never been acceptable to me. While you can get some slight out of focus areas to look a bit sharper, along comes a huge load of artifacting.

Yes, admittedly, deconvolution will not work miracles. You can restore slight focus errors, not significant ones. However, please remember that you can reduce artifacting by using the highest quality source image you can get.


And this has nothing to do with RAW vs. JPEG anyway, since these programs do not use RAW data, just any image. So also on a JPEG.

But this does have something to do with RAW vs JPEG. As you know, RAW files are 16-bit, and contain ~12 bits of non-lossy tonal data. Since the programs are doing heavy-duty math on the files, I can only assume that having 4 more bits of precision is helpful. And that means 16-bit non-lossy RAW files are preferable to 8-bit lossy JPEG files.

EDIT: actually, I know Unshake prefers using non-lossy files as the source, and the creator of Unshake even says to avoid JPEGs for their lossiness, artifacting, and smoothing. Unshake cannot use RAW files, of course, nor can it use 16-bit TIFF files. I use 16-bit uncompressed PNG source files, which Unshake can use no problem. The stand-alone version of Focus Magic can only use JPEGs though.

e_dawg
08-12-2007, 12:43 PM
Okay, here's some before and after.

Minimal focus error example

Before
http://i211.photobucket.com/albums/bb61/e_dawg8/public/kittycropped2edbefore.jpg

After
http://i211.photobucket.com/albums/bb61/e_dawg8/public/kittycropped2edafter.jpg

no EXIF data left after pp, so... D40, 18-55 II, f=45 mm equiv, CW metering, on-camera flash (-0.7 EV), 800 iso, 1/60 s, f/7.1, RAW > CNX > Unshake

Significant focus error + motion blur example

Before
http://i211.photobucket.com/albums/bb61/e_dawg8/public/DSC_0105adjresizebefore.jpg

After
http://i211.photobucket.com/albums/bb61/e_dawg8/public/DSC_0105adjresizeafterdc.jpg

D80, 18-200/VR, f=75 mm equiv, matrix metering, 200 iso, 1/60 s, f/8, RAW > CNX > Unshake

As you can see, deconvolution has its limits. It can only restore focus a limited amount. Maybe 15% for sake of discussion? For example, if your focus is off by maybe 20%, you'll be golden. However, if your focus is off by 50%, good luck.

Alex D80
08-12-2007, 11:35 PM
After
http://www.pbase.com/e_dawg/image/83773580/original.jpg

D80, 18-200/VR, f=75 mm equiv, matrix metering, 200 iso, 1/60 s, f/8, RAW > CNX > Unshake

As you can see, deconvolution has its limits. It can only restore focus a limited amount. Maybe 15% for sake of discussion? For example, if your focus is off by maybe 20%, you'll be golden. However, if your focus is off by 50%, good luck.

I don't know what you guys are looking at.. but I sure know what I am looking at..








their shoes of course.. what were you thinking!

<Thanks for the samples, I just had to throw this in.. >