Raw vs Jpeg

[ajohnw]

I didn't want to complicate things Ted and get into gamma etc and the actual dynamic range of monitors varies. The important aspect is that the channels limit both the number of "distinct" colours that a monitor can show and the degrees / steps of brightness. Working from raw doesn't change that aspect at all. Nor does editing jpg's.

I then posted a link to a test shot for monitors that does give a quick idea of just how "good" a particular monitor is. Chances are many wont be able to see all of the divisions in the squares. Another limitation. As a check it's pretty sensitive and showed that in my case I should have recalibrated my monitor when I changed the lights here.

Any how I usually shoot both and which gets worked on is dependent on a number of factors and the camera. It's far more likely to be raw if the shot was taken with my Nikon V1. Less likely with my EM-1. On compacts without raw jpg's every time. I've done rather a lot of that.

John
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[george013]

I didn't want to complicate things Ted and get into gamma etc and the actual dynamic range of monitors varies. The important aspect is that the channels limit both the number of "distinct" colours that a monitor can show and the degrees / steps of brightness. Working from raw doesn't change that aspect at all. Nor does editing jpg's.

The title of this thread is "raw vs jpeg".
One of the advantages of raw is that after the conversion, so in the converter, you're working on a 12 or 14 bit rRGB-raster image. When editing that same picture from a jpeg, you 1. use an already compressed image and 2. of only 8-bit color depth. Without editing you probably won't see any difference. But after editing you might see, on that same monitor.

You can also save your image in-camera as a 16-bit tiff. Conversion has been done in the camera. The tiff is a RGB-raster based image written to disk. It will be several times as big as a raw. I don't know why that choice is in the camera.

About the colours. A digital image doesn't have colours, nor does it have a dimension or contrast. All of these are given by the output device.

Pat,
I read that article quickly. He has some points but also a lot of mis-points(?).
When saving an image as jpeg, the raster image in memory is written to disk in a compressed way. Some programs use a flag indicating if the image has changed, resulting in NOT SAVING the image when wanted. It is already there.
I just tried IrfanView. It doesn't use the flag and overwrites the jpeg with a smaller size. I know Nikon CaptureNx2 doesn't.
From the bottom of his article

Remember, it is important that you preserve the integrity of your JPEG file. In addition to insuring that your retain the original file without over-writing it (make alterations to a copy), it is wise to turn off any in-camera processing, such as sharpening, contrast, and hue adjustments, or set them to low levels. Not only should you make these modifications in Photoshop, where you can do a more precise job, you want as "clean" a JPEG file as possible. Any processing done in-camera to a JPEG file can not be undone. Most dSLRs will allow you to turn off or modify in-camera processing, although some point-and-shoot digital cameras will not.

I would say that's why you should use raw.

George

[GrahamS]

I'm lost here. As far as I know, a RAW file is not an image format file, it is a data file. In order to view the data as an image, it needs to be converted into a jpg file. This conversion is done in-camera and the resultant jpg "viewing" file is embedded in the RAW data file and this is the file that is used when you import and view a RAW file on your PC or when you view the RAW file on the LCD screen on your camera. This is why RAW files are camera specific. If you edit the RAW file in image editing software, you cannot re-save your edits as a new RAW file. You can only 1) save the edit information either as a separate file (sidecar XMP file - this is what Lightroom and Photoshop do) or 2) embed the edit info into the RAW file IF IT IS A DNG FILE. In either case the original RAW data remains untouched. The only way to create a "new" integrated file from the edited RAW file is to create a jpg or a tiff file. Correct me if I am wrong.

[William W]

. . . I think this is much ado over very little.

I agree. But the cited article hits on a few not so often mentioned points, but doesn't seem to expand upon them - especially for example the relevance of JPEG only capture to adhere many to Editorial Guidelines apropos news commentary and other publishing/journalism purposes.

Anyway . . . "raw vs. JPEG" in any guise is one of those gems which is always a good topic for a Forum discussion.

*

. . . The biggest disadvantage of jpeg is not the loss of detail, which he takes great pains to show isn't large. The main issue [capturing ONLY in JPEG format] is the reduction in flexibility in editing the image because of the loss of information.

I agree again. [my added text is included to clarify my own opinion].

So I think, if it is "answer" one is looking for, then the "answer" is a very simple answer:

Capture only in raw if you want to, or need to do Post Production editing
Capture only in JPEG if you do not want to, or are not allowed to do Post Production editing.
Capture in BOTH, if you are unsure of what you might need or want to do.

Since cutting over to Digital in 2004, when using DSLR's I have always captured raw + JPEG and with the in-camera JPEG default settings being 'neutral'.

WW

[pnodrog]

I'm lost here. As far as I know, a RAW file is not an image format file, it is a data file. In order to view the data as an image, it needs to be converted into a jpg file. This conversion is done in-camera and the resultant jpg "viewing" file is embedded in the RAW data file and this is the file that is used when you import and view a RAW file on your PC or when you view the RAW file on the LCD screen on your camera. This is why RAW files are camera specific. If you edit the RAW file in image editing software, you cannot re-save your edits as a new RAW file. You can only 1) save the edit information either as a separate file (sidecar XMP file - this is what Lightroom and Photoshop do) or 2) embed the edit info into the RAW file IF IT IS A DNG FILE. In either case the original RAW data remains untouched. The only way to create a "new" integrated file from the edited RAW file is to create a jpg or a tiff file. Correct me if I am wrong.

I am about to go to bed so I will correct you more fully in the morning unless someone does it earlier....

But in the meantime simply put RAW, Tiff, Jpeg etc are all image files in various formats requiring different software to convert them to a raster array in your computer's memory that suitable drivers can use to output it to a monitor, printer or a software routine can save in another image file format.

RAW is one of a special class of file called image sensor file format but it is essentially an image file. Certainly not audio, text, accounts or any other type of information.

[Mike Buckley]

If you edit the RAW file in image editing software, you cannot re-save your edits as a new RAW file. You can only 1) save the edit information either as a separate file (sidecar XMP file - this is what Lightroom and Photoshop do) or 2) embed the edit info into the RAW file IF IT IS A DNG FILE.

Some software, such as the primary software I use, indeed saves the edits only to the raw file. Some software gives you the choice of saving to the raw file or other formats. Some software allows you to save only to other formats.

[george013]

[/QUOTE] [QUOTE]

I'm lost here. As far as I know, a RAW file is not an image format file, it is a data file. In order to view the data as an image, it needs to be converted into a jpg file.

Look at the image I posted and nobody wants to see. The raw file contains the sensor info in a color filter array. A big que of sensor data, each containing the digitized value of the light that hit that sensor element. This is a value representing only one color R,G or B. The converter converts those values to a pixel containing values of R,G and B. The result is a RGB raster image. That's where the monitor, the software etc. is working with. JPG, TIFF, DNG,PNG etc. are diskfile formats of that raster image.

This conversion is done in-camera and the resultant jpg "viewing" file is embedded in the RAW data file and this is the file that is used when you import and view a RAW file on your PC or when you view the RAW file on the LCD screen on your camera.

Normaly a thumbnail is added to the raw-file, in jpeg format. But when you want to work on it, you need to convert the raw-file to a RGB-raster-file.
I don't know of other brands, but Nikon also adds a real size jpeg in its raw-file, of basic quality. That's the one I see when examining a raw-file in irfanview.

This is why RAW files are camera specific. If you edit the RAW file in image editing software, you cannot re-save your edits as a new RAW file. You can only 1) save the edit information either as a separate file (sidecar XMP file - this is what Lightroom and Photoshop do) or 2) embed the edit info into the RAW file IF IT IS A DNG FILE. In either case the original RAW data remains untouched. The only way to create a "new" integrated file from the edited RAW file is to create a jpg or a tiff file. Correct me if I am wrong.

Again I can only speak of Nikon. When I convert a raw-file in CaptureNx2 and edit that file, alle the editing commands are embedded in the raw-file and a high quality jpg is added. That's what the old Capture is doing. You can even save more edits in the same raw-file. Only a jpg of high quality is embedded of the last one. Other converters work with sidecar files. But the essence is the same.

That's also why I love the old CaptureNx2. Only one file containing the raw, the done editing and the full size jpg. Easy to view in iview, full size. I even can see on the thumbnail in iview if that file has been edited.

George

[xpatUSA]

I didn't want to complicate things Ted and get into gamma etc and the actual dynamic range of monitors varies.

We must be talking at cross-purposes because I did not mention gamma and I don't know why it got introduced - please explain. Of course the dynamic range of monitors varies . . some even dynamically

The important aspect is that the channels limit both the number of "distinct" colours that a monitor can show and the degrees / steps of brightness. Working from raw doesn't change that aspect at all. Nor does editing jpg's.

My post was only about dynamic range but thanks anyway.

[rpcrowe]

I didn't mention this but, one reason that I always shoot RAW is that I enjoy working with Adobe Camera RAW... Of course, you "can open a JPEG in ACR but, why would I do that?

OTOH, I see absolutely no reason for ME to shoot in other than RAW. I can understand the need of a sports photographer or news photographer to shoot JPEG in order to immediately forward the images to an editor. I don't have that need or requirement.

I have plenty of memory in the form of CF cards, which I have purchased over the years when the cards were on sale. The CF cards are so sturdy that I can (and do) use them for years and thousands upon thousands of images.

My 7D and 7DII cameras have the ability to shoot a very decent number of shots in RAW before the buffer is filed up.

I will, occasionally shoot RAW + JPEG when I need to give my images to someone before I can get to my home computer...

However, I am experimenting using my Chromebook to download my RAW images and to transfer these to a small physical size but, large capacity external herd drive.

[ajohnw]

Interesting point Richard. Some time ago I came across a video by one of the Adobe people showing what can be done in Camera Raw to jpg's. It was very impressive. At the time as I don't use PS at all I was interested in just what was available especially as some people who were about that time were struggling with PS.

John
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[Cantab]

Richard,

I was pleased to read your comments about the typical longevity of memory cards.

In order to avoid confusion for some readers, am I correct in thinking that your reference to RAW for sport and news photographers was meant to be a reference to JPEG?:

OTOH, I see absolutely no reason for ME to shoot in other than RAW. I can understand the need of a sports photographer or news photographer to shoot RAW in order to immediately forward the images to an editor. I don't have that need or requirement.

underlining of RAW added by Bruce

[Manfred M]

Richard,

I was pleased to read your comments about the typical longevity of memory cards.

In order to avoid confusion for some readers, am I correct in thinking that your reference to RAW for sport and news photographers was meant to be a reference to JPEG?:
underlining of RAW added by Bruce

Good catch.

I also know some wedding and event photographers who shoot jpeg for the same reason.

[JBW]

I don't shoot RAW as I am not really into a lot of PP.

http://www.michaelfurtman.com/jpeg_myths.htm

Hmm, not getting a hyperling so you have to copy and paste to get to the site.

The Real Truth About JPEG images by Michael Furtman

I came across this web site that had a very good explanation to the difference between RAW & JPEG.
Some interesting reading.

I shoot RAW for the added pp possibilities. This morning my wife is off to a wedding and thought it would be nice to take some snapshots. I set the camera to gold auto, showed her how to take off the lens cap, turn on the camera and get it to focus. With a little pp this is her JPEG test shot. I really believe everyone should set up their gear anyway they like.

[leprechaun]

Question JBW,
What is Gold Auto? Or is this being the camera set to auto.

[JBW]

Question JBW,
What is Gold Auto? Or is this being the camera set to auto.

The a58 comes with two auto settings on the dial. Gold and Green.

[rpcrowe]

Richard,

I was pleased to read your comments about the typical longevity of memory cards.

In order to avoid confusion for some readers, am I correct in thinking that your reference to RAW for sport and news photographers was meant to be a reference to JPEG?:
underlining of RAW added by Bruce

Yes, you are correct. That was a typo error. My fingers typed out RAW when my brain was signalling JPEG I have corrected it!

Re: Longevity of CF cards. I have had a CF card go through a washing machine in the pocket of my jeans and have also had a puppy try to use the card as a chew toy. The wash cycle caused no problems and I was able to rescue the images off the puppy chewed card but, did retire that card (the only card I have ever retired because of physical damage!) Actually, the card was still usable in an emergency but, why take a chance

Some of my CF cards are over 10-years old and, like the Energizer Bunny keep going and going. I have retired some cards because they are slower than the cards that I use regularly and other cards have been put in semi-retirement because they are to small in memory (I actually have a 128 mb CF card that "could" be used... I do keep a selection of the slower cards in a CF wallet in the glove box of my car. Just in case I forget to bring my go-to CF cards. That has happened only once but, the extra cards were viable and saved the day for me...