What's Wrong w/JPG Compared to RAW?

[dwdallam]

What's "really" Wrong w/JPG Compared to RAW?

[kenstrain]

on some fora that post would have quite an effect  

May I first suggest that you try taking various subjects both ways and then you'll get an answer you can trust beyond all doubt?  If you cover your normal range of subjects you should find an answer soon.

Personally, I find the ability to choose the characteristic curve in the raw converter the second most significant advantage of the digital photographic process (high quantum efficiency being the first).

One example: JPEG format has insufficient shadow levels in the case where expansion of shadows is desired. 256 levels and 3 channels suffice for the output end, but not for the input end, unless your camera's inbuilt curve(s) match(es) your needs - it will often do so, but *in my experience* by far not always.

Ken

[Graham Welland]

Nothing 'wrong' with jpg - the reality is that raw gives you much more opportunity to process the original image using whatever settings you want to use for white balance, contrast curves, colour settings, different convertors for colour fidelity, etc, etc. Typically jpg images are processed in camera with the white balance applied, contrast curve applied, possibly in camera sharpening and your chosen colour space applied. Once these have been set it's harder to process the image without degrading the original and any information lost/discarded in the in-camera processing is lost forever.

If you turn off all in camera processing with jpg then typically the only setting that gets burnt into the jpg image (depending upon your camera) is the white balance at time of capture. If you set your white balance manually or use something like an expodisc/grey card then you can prodcue base images that can be managed just as well as raw captures. If you get the white balance wrong then it's a lot more work to attempt to fix things up later.

The analogy that some people use is to compare raw to the negative and jpg to the print.

[Jonathan Wienke]

RAW gives you 100% of the dynamic range of the sensor and 100% of the color gamut of the sensor. JPEG gives you neither. You typically lose at least 1 stop of DR during in-camera JPEG conversion, and any colors that fall outside of the destination color space (ARGB or sRGB) are clipped. You are also committed to the white balance the camera uses during JPEG conversion, as well as the camera's internal color profiles, which are typically no better than generic printer profiles for color accuracy. In addition, conversion to 8-bit limits the extent of edits you can do on the image before banding and posterization become visible, and JPEG compression always introduces some degree of compression artifacts into the image.

With RAW, you can tune the color conversion accuracy in the RAW converter to your particular camera either with a custom camera profile or via the ACR calibration tab. This can eliminate 90+% of the color corrections you would need to do on camera JPEGs. You also have complete flexibility in assigning white balance after the fact. With a properly-configured RAW converter, in most cases you can get dead-on color by simply setting the white balance correctly. And with ACR/Bridge, Capture One, and several other RAW converters, you can apply white balance and other conversion settings to dozens or hundreds of RAWs simultaneously very quickly. Doing the same to JPEGs requires that they be opened, the color adjustment(s) applied, and then re-saved. I spend far less time in front of the computer adjusting images when shooting RAW than when shooting JPEG. With RAW, I can automate almost everything in the color adjustment process, so that images have hand-tuned white balance and other settings without my needing to individually edit each image. This means that I can post web galleries of a shoot that are very close to the client's final delivered product witout wasting time hand-editing all the non-selects.

On top of all this, you get all of the inherent advantages of 16-bit workflow that you do not get with JPEGs. I shoot about 99% RAW.

[digidon]

I began shooting only hi-res JPG at first( 20D).  Then after learning more about raw I began to shoot hi-res JPG + raw.  Then as I gained confidence in processing raw I shot low=res JPG + raw just to provide a thumbnail for the raw in windows( I know there's a download for viewing raw in windows XP but it requires SP-2 and I'm afraid of SP-2).  After reading Jonathan's excellent explanation of the advantages of raw I plan to shoot only raw, even if it's only in defiance of anyone( in-camera) tampering with my image before I see it.
That's a comment but my question is , is there any drawback to SP=2 with PS-CS2...any problems?
Don

[Jonathan Wienke]

I've not experienced any issues with SP2 at all.

[61Dynamic]

( I know there's a download for viewing raw in windows XP but it requires SP-2 and I'm afraid of SP-2)

I have not had any issues with SP2 either. the huge number of security enhancements makes it a must. You shouldn't be afraid of SP2, you should be afraid of not having SP2.

[Steven M Anthony]

Aside from just figuring out the defaults in SP-2, the only horror stories I've heard regarding SP-2 related to auto updating XP on laptops.  Not sure if those stories are cyberspace legends or not.  But they've kept me from updating.  


Maybe once I get my new laptop and transfer all by business-related files to it I'll try updating the old laptop with SP-2, to see if my fears were warranted.

[Jonathan Wienke]

Aside from just figuring out the defaults in SP-2, the only horror stories I've heard regarding SP-2 related to auto updating XP on laptops.  Not sure if those stories are cyberspace legends or not.

They are. If you're worried about it, simply set the auto-update feature so that it downloads the updates automatically, but requires user action to actually install them. I'm running XP SP2 on a Fujitsu Lifebook and have had zero problems with it. You're far more likely to have problems due to the numerous unpatched security holes leaving your system totally vulnerable to hackers in its current state.

[Steven M Anthony]

They are. If you're worried about it, simply set the auto-update feature so that it downloads the updates automatically, but requires user action to actually install them. I'm running XP SP2 on a Fujitsu Lifebook and have had zero problems with it. You're far more likely to have problems due to the numerous unpatched security holes leaving your system totally vulnerable to hackers in its current state.

Fortunately, my work isn't that interesting and doesn't draw hackers!  

You are probably right.  I do run my laptop through a router, which helps thwart hackers, right?  Or maybe that's just what the hackers want us to believe...  

At this point I should have my new laptop in a couple of weeks.  I'll try your method once I get set up on the new one and let you know how it works out.

[61Dynamic]

If all else fails, SP2 can be uninstalled...

[Digi-T]

I don't have raw as an option on my current prosumer camera so I have to use jpegs and make the best of them. I have been very pleased with the results even with adjustments to white balance, levels, curves and most any other edits. But this isn't to say that my images couldn't be better with raw because in a lot of cases I'm sure they could be. If I had a nice DSLR with raw capabilities in some cases I might still use jpeg for many things like sports or other fast action where I would shoot quickly but with nearly all other shots I would definitely shoot raw. It just seems to be the most logical choice because it provides the very best quality. Even if many shots look nearly identical in either format it doesn't make sense to use a lesser quality no matter how small if you don't need to. I figure I never really know how I might use one of my images one day so it is a good idea to make as good an original file as I reasonably can. With all this said I still think jpeg gets slammed more than it should. If it is all you have, like me, then don't worry about it because the quality can still be very good and you can still do tons of editing to most shots with little image degradation.

T

[jani]

This isn't nice of me, but I think it needs to be public, because it's a serious wake-up call.

Fortunately, my work isn't that interesting and doesn't draw hackers!  

The "hackers" [span style=\'font-size:8pt;line-height:100%\'](wrong term, but I'll play along for the sake of the discussion)[/span] don't care what your work is.

They are most likely spammers or other kinds of script kiddies who just want another zombie to use in DDoS attacks.

 - script kiddie: person who doesn't know more about computers than Abraham Lincoln did, but wants to cause damage
 - zombie: a computer that's remotely controlled by a usually malign third party
 - DDoS attack: distribued denial of service attack, a type of Internet attack using usually hundreds, thousands or hundreds of thousands of computers to attempt to take down e.g. a corporation's web site and other services

If your PC is a zombie, you might just not notice it, except that it sometimes is a bit slower, or your Internet connection isn't working quite as fast as you thought it did.

In other words, pretty much indistinguishable from normal Windows behaviour.

You are probably right.  I do run my laptop through a router, which helps thwart hackers, right?  Or maybe that's just what the hackers want us to believe...  

A router only routes traffic. That is, it directs traffic where the traffic is supposed to go. While a router technically can be configured to filter traffic based on certain criteria, it basically does nothing that thwarts anyone, as long as it allows your PC to connect to the Internet.

The typical time for an unpatched Windows box to be turned into a zombie after it's connected to the Internet is less than 15 minutes. The world record is 8 seconds.

You are a security risk for the rest of the Internet's users by using an unpatched computer.

[61Dynamic]

I'll chime in to confirm what jani said. (for those curious, the term is really Craker. Hacker is just what the media ignorantly latched on to).

Routers help thwart crakers in the sense that it makes your computer hidden from the internet and not directly accessible. A router is a basic firewall in that it will flat out ignore any incoming data that was not specifically requested by a computer on your local network.

Even with a router your computer is at risk of infestation by a multitude of things (spyware, malware, trojans, hijackers, viruses, worms and many many more). These things can get around the router by exploiting insecure software.

[Mark D Segal]

I went through pangs of anguish before installing SP2 also because of Microsoft's legacy of dumping insufficiently tested software on the market which then need patches for the patches for the patches; however, I was reliably informed that SP2 was the best prepared release they ever produced and I had nothing to fear. That advice was correct. It was a seemless download and works fine. (Dell 8200, 2.2 Ghz, 1.536 GB RAM). It seems that as long as the computer can handle XP OK, it can manage SP2 as well.

[dwdallam]

OK that's some great information. I have a few other questions on this topic. Please let's stay on topic too

So when you shoot, for instance, the 20D in RAW mode, no settings work in the images recording process except the exposure settings? Pretty much just like a film camera would record an image on the negative?

Can you explain this camera profile a little more? Can I use one with my new 20D? Do I need to?

Can I use Adobe PSCS2 without any plugins for RAW adjustments, or do I need something extra?

Next, I'll go read some essays on this. If any of you ahve any links, go ahead and post them for me--us.

[Jonathan Wienke]

So when you shoot, for instance, the 20D in RAW mode, no settings work in the images recording process except the exposure settings? Pretty much just like a film camera would record an image on the negative?

That is basically the case. The other settings are placed in the metadata so that the RAW converter can tell what the camera settings were, but you are 100% free to ignore the tags.

Can you explain this camera profile a little more? Can I use one with my new 20D? Do I need to?

Can I use Adobe PSCS2 without any plugins for RAW adjustments, or do I need something extra?

http://www.visual-vacations.com/ColorManag...01/04camera.htm

[61Dynamic]

I have a generic profile for the 20D on my site that can help yo get started. It's not a substitute for a custom one since each camera varies a bit.

[dwdallam]

I have a generic profile for the 20D on my site that can help yo get started. It's not a substitute for a custom one since each camera varies a bit.

I did some more reading and talking with a person here where I live . He has a 20D aslo and confirmed that RAW is settingless pretty much, except exposure and focus.

I think that is excellent. Why let the camera process that information? What I was doing with my F828 was setting all of the camera processing settins to 0--or do as little as possible--and then doing teh color in PS. So my thinking was the same, but my choice of data was wrong--not jpg, RAW.

I'll check out those links, and thanks.

[Digi-T]

If time is important to you (as it is with most of us) why not set some things like white balance in-camera so that you can edit faster and then change your setings only IF you need to? This should speed up your editing and if you save jpegs with your raw files then they will be ready enough to show as well without also needing to be processed. It just makes sense to me to get close right out of the box when you know you can still change everything later.

T