# RAW Vs. JPEG



## timarp000 (Sep 29, 2012)

I know that they are many threads regarding to this topic but both formats have their own references and some of the people that i've asked just seem one-sided and dont want to accept that each format do have advantages and disadvantages. So hopefully people here wont do the same. When you do vote. tell me the advantages of the format you voted for.


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## 480sparky (Sep 29, 2012)

I can't vote because my choice isn't listed.

I typically shoot raw for total flexibility in post.  I will shoot jpeg if I need to 'fire away' dozens of shots quickly, or am just taking a shot to post online or email.


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## memento (Sep 29, 2012)

I shoot both. I try to get it right in the camera the first time. If I need to edit, then I have the raw file.


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## KmH (Sep 29, 2012)

I too shot both, but mostly I shot Raw.

I shot JPEG when time constraints didn't allow post processing, like selling images on site at an event.

The bottom line regarding the difference between the 2 file types is - Bit Depth
Tutorials on Color Management & Printing

Raw is like a film negative and is an unfinished image that has to be 'developed' and then adjusted before a print is made.
JPEG was designed to be a finished ready-to-print format. As such JPEG has little, if any, editing headroom. JPEG is a lossy, compressed file type. About 80% of the color information the camera's image processor developed gets thrown away to make a JPEG (the lossy part). All those millions of pixels get converted into 8x8, 8x16, or 16x16 pixel blocks known as Minimum Coded Units (MCU) (compression).


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## snowbear (Sep 29, 2012)

I'm also bilingual, but shoot raw more than JPEG.


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## unpopular (Sep 29, 2012)

DAMN THIS TOPIC. DAMN IT ALL TO HELL.


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## snowbear (Sep 29, 2012)

unpopular said:


> DAMN THIS TOPIC. DAMN IT ALL TO HELL.



'tis a religious topic, like Canon v. Nikon.


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## unpopular (Sep 29, 2012)

The way I see it is you should always shoot RAW unless you have a reason to shoot JPEG.

OTOH, I wish that cameras would at least give you a lossless 8-bit and 16-bit PNG option. Something in the middle would be nice.


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## Garbz (Sep 30, 2012)

JPEG are smaller. End of benefits. I can fully understand why people seem onesided. Unless you need to fire away a billion shots in a short time space and then turn over straight to a client or non-raw capable device there's no benefit, only downsides.


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## TonysTouch (Sep 30, 2012)

You can always batch process your JPGs, but you can't get the trashed information back.


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## IgsEMT (Sep 30, 2012)

Ahhh, the great debate 

For me, it depends what I'm shooting.

RAW: 
commercial shoot.  
portrait sessions (outdoors) - IN CASE lighting changes faster then I'd like it to, I have the ability to rescue the shot I want/need.

JPG: In studio portrait session. White balance is preset, lighting is controlled to the 1/10th of it. All that's left is the camera angle and subject in front of the camera.

Events are really 50/50 and depends for who I'm shooting. Some studios want me to shoot ONLY RAW, others medium jpgs. On my jobs, its a 50/50 depending on the importance of the shot and what will it be in final batch of things.

Realistically, you need to *start* shooting, experiment with both formats and see which one works _better_ for you.


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## zombiemann (Sep 30, 2012)

The only time I shoot JPEG over raw is when I'm doing very low light photography like star trails.  The in camera noise reduction is better than what I am capable of doing in post.  I could very well be missing something though


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## Steve5D (Sep 30, 2012)

I shoot both...


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## fjrabon (Sep 30, 2012)

JPEG for sports.  Raw for most everything else.


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## SUNR15E (Nov 8, 2012)

snowbear said:


> unpopular said:
> 
> 
> > DAMN THIS TOPIC. DAMN IT ALL TO HELL.
> ...




Obviously Nikon......lol

SUNR15E


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## JaronRH (Nov 9, 2012)

My camera can produce JPGs?!  Who knew!


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## mommyof4qteez (Nov 9, 2012)

RAW...can do so much more with the image in post processing....


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## RinaldiPhotos (Nov 11, 2012)

I got hooked on Raw accidentally, I was shooting a game in Fort Wayne, and my I didn't even know my Camera was on Raw until I got the results.  The only real problem I have is when I come to print the picture out.


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## kathyt (Nov 11, 2012)

I shoot in raw 95% of the time so I have the most control possible in PP.  When I do change over to JPEG it is either for candid shots or for non-client work.


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## panblue (Nov 11, 2012)

timarp000 said:


> I know that they are many threads regarding to this topic but both formats have their own references and some of the people that i've asked just seem one-sided and dont want to accept that each format do have advantages and disadvantages. So hopefully people here wont do the same. When you do vote. tell me the advantages of the format you voted for.



I capture both. Archive the raw and share the jpegs.


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## 2WheelPhoto (Nov 11, 2012)

panblue said:


> timarp000 said:
> 
> 
> > I know that they are many threads regarding to this topic but both formats have their own references and some of the people that i've asked just seem one-sided and dont want to accept that each format do have advantages and disadvantages. So hopefully people here wont do the same. When you do vote. tell me the advantages of the format you voted for.
> ...



I did too till I got this D800...its eats memory cards for brunch and then some =)


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## panblue (Nov 11, 2012)

2WheelPhoto said:


> panblue said:
> 
> 
> > timarp000 said:
> ...



How big are your cards? I shoot ~10mp on 16GB/8GBs.


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## Garbz (Nov 12, 2012)

I shoot on 8GB cards. 100 photos fit on the card. It was quite a shock upgrading to a D800.

But worse still is my laptop I take on vacation. USB2.0, no USB3.0 which the D800, and my laptop harddisk support. It takes 45min to download the photos.


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## Kolia (Nov 12, 2012)

Garbz said:


> I shoot on 8GB cards. 100 photos fit on the card. It was quite a shock upgrading to a D800.
> 
> But worse still is my laptop I take on vacation. USB2.0, no USB3.0 which the D800, and my laptop harddisk support. It takes 45min to download the photos.



80MB per picture !?!?!


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## runnah (Nov 12, 2012)

Raw unless I am doing a time lapse.


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## JSER (Nov 12, 2012)

The only time I shoot RAW AND JPEG is weddings


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## Garbz (Nov 13, 2012)

Kolia said:


> 80MB per picture !?!?!




Yep, more if I shoot in TIFF instead of RAW as I'd end up with 16bit files rather than 14bit.


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## JohnYoung (Nov 13, 2012)

I shoot both, RAW when its important like weddings etc 


JPEG when out and about taking shots of family etc - not that family isn't important but you know what I mean


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## JDFlood (Nov 13, 2012)

Both, RAW I use, jpg goes on backup (SD) card in D800. I erase the jpgs periodically. But if I need to post something quick, the jpg is there. I have several 32gb cards, so the D800 presents no space problems. JD


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## RinaldiPhotos (Nov 17, 2012)

panblue said:


> timarp000 said:
> 
> 
> > I know that they are many threads regarding to this topic but both formats have their own references and some of the people that i've asked just seem one-sided and dont want to accept that each format do have advantages and disadvantages. So hopefully people here wont do the same. When you do vote. tell me the advantages of the format you voted for.
> ...


I have a TI and a T2, would I be able to do that with my camera or no?  
On another note, I will be stocking up on Blackfriday.  Going to get 5 of t 3 TB hard drives back up, and around 12-15 32GB memory cards, and probably the same amount of flash drives.


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## AlexanderB (Nov 17, 2012)

KmH said:


> I too shot both, but mostly I shot Raw.
> 
> I shot JPEG when time constraints didn't allow post processing, like selling images on site at an event.
> 
> ...


This is totally misleading IMO. The color information is "not thrown away" when using JPEG. The values from sensor undergo a non linear transformation - gamma correction and only after that it compressed throwing away only information not relevant to human vision. The gamma correction is a crucial step allowing to keep almost any relevant information. The only reason to shoot raw if you want to do gamma correction using your algorithm (software), not one in camera. If raw have more "editing headroom" then the in camera algorithm sucks, but usually it is not the case.


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## imagemaker46 (Nov 17, 2012)

The amount of information lost between  Raw and Jpeg is minimal, to most they wouldn't even know the difference. Some people consider shooting jpegs as unsuitable for professional work, that is simply wrong.  People will argue over the amount of information lost with jpeg compression, again this is so small that to the naked eye, you are likely not going to see a difference.

National Geographics first all digital copy was all shot jpeg.  What it still comes down to, if you have a perfect exposure in camera then there is little difference.   It is a personal choice.


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## Helen B (Nov 17, 2012)

I shoot raw almost exclusively, even with my compact camera. The two main differences I find are dynamic range and noise (the ideal raw exposure is usually greater than the ideal JPEG exposure, hence a reduction in noise) with colour space occasionally being important as well (raw usually has a much larger colour space than the JPEG options of Adobe RGB and sRGB, so those options do indeed 'throw colours away').


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## HughGuessWho (Nov 17, 2012)

Why isn't there an option for Bacon?


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## manicmike (Nov 17, 2012)

I just started shooting RAW about a week ago and I don't know why I waited so long.

RAW is so much more flexible to work with. Lots of pics in a hurry, I use JPEG.

I prefer RAW though.


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## KmH (Nov 17, 2012)

AlexanderB said:


> This is totally misleading IMO. The color information is "not thrown away" when using JPEG. The values from sensor undergo a non linear transformation - gamma correction and only after that it compressed throwing away only information not relevant to human vision. The gamma correction is a crucial step allowing to keep almost any relevant information. The only reason to shoot raw if you want to do gamma correction using your algorithm (software), not one in camera. If raw have more "editing headroom" then the in camera algorithm sucks, but usually it is not the case.



Today's digital cameras make 12-bit depth (4096 discrete colors per color channel, as defined by colormetric interpretation of the Bayer array) or 14-bit depth (16,384 discrete colors per color channel, as defined by colormetric interpretation of the Bayer array).
JPEG is limited to an 8-bit depth, or 256 discrete colors per color channel. What happens to the other 3840 or 16,128 discrete colors?
Banding and posterization can result in image gradients because JPEG lacks enough colors to render the gradient without visible steps.

None of the luminosity data the image sensor records is discarded.

The image sensor records a linear gamma (1). Human vision cannot be modeled accurately using a gamma curve, but Raw converters usually use a non-linear gamma encoding between 1.8 and 2.2, close enough to match the way human eyes see the world.

http://www.adobe.com/digitalimag/pdfs/linear_gamma.pdf
Also see - Real World *Camera Raw* by Bruce Fraser and Jeff Schewe.

Here is an approximation of an image having a linear gamma and no colormetric interpretation of a Bayer array, but converted to JPEG for online display:






The same photo with a non-linear gamma applied, colormetric interpretation, and conversion to JPEG for online display.


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## imagemaker46 (Nov 17, 2012)

KmH said:


> AlexanderB said:
> 
> 
> > This is totally misleading IMO. The color information is "not thrown away" when using JPEG. The values from sensor undergo a non linear transformation - gamma correction and only after that it compressed throwing away only information not relevant to human vision. The gamma correction is a crucial step allowing to keep almost any relevant information. The only reason to shoot raw if you want to do gamma correction using your algorithm (software), not one in camera. If raw have more "editing headroom" then the in camera algorithm sucks, but usually it is not the case.
> ...



I have not got a clue what any of this means, and to be honest, I think even if I did, it wouldn't affect how I shoot.


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## greybeard (Nov 17, 2012)

I think of Jpeg as a place I want to end up but not start.  It is just the same as recording an audio master in mp3 instead of wav.  A compressed file is an ok place to end up but not a good place to start.  (jmho)


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## unpopular (Nov 18, 2012)

I think of a jpeg as a file format of last resort. it's seriously terrible. 

i wish cameras at least gave the option for lossy, lossless, 8 and 16 bit PNG. JPEG is such a 20th century format.


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## AlexanderB (Nov 18, 2012)

KmH said:


> Today's digital cameras make 12-bit depth (4096 discrete colors per color channel, as defined by colormetric interpretation of the Bayer array) or 14-bit depth (16,384 discrete colors per color channel, as defined by colormetric interpretation of the Bayer array).
> JPEG is limited to an 8-bit depth, or 256 discrete colors per color channel. What happens to the other 3840 or 16,128 discrete colors?
> Banding and posterization can result in image gradients because JPEG lacks enough colors to render the gradient without visible steps.


Indeed these 12 or 14 bit values in RAW file as you say code linear intensity. But storing linear values is very inefficient, as human vision is non linear, approximately logarithmically of intensity. If you apply gamma curve to the linear values you can use bit bandwidth much more effectively relatively human vision properties. It was my point that 8-bit gamma corrected values store almost all the information actually useful from RAW file (in case if jpeg codec in camera works properly). Banding and posterization can appear if you have an improperly exposed image and trying to fix it in post-processing. Say you have underexposed image and you trying to 'fix' exposure in graphic editor. But both jpeg and RAW are equally susceptible to this, because if image is not exposed properly you've lost bits of dynamic range already in RAW hence the banding. Instead of 14 bit device you have used only say 6 bit. And 6 bit in linear range is a banding and posterization catastrophe. Heavily underexposed RAW image contains 14 bit of trash and nothing will help it. I will repeat that RAW is useful if you know you want to use own conversion algorithm, that is the main its application. You cannot fix underexposed photos in post-process even if you use RAW. For small amount of exposure correction (-/+ 1 stop) jpeg will do just fine as RAW.


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## unpopular (Nov 18, 2012)

I have been experimenting with ETTR in conjunction with non-standard input gamma encodings, with some success. Rather than having my raw processor encode a standard 2.2 nonlinear gamma, I adjust gamma based on shadow placement. 

It works well and effectively addresses the efficiency problem, though this ability isn't typically available in most raw processors.


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## Majeed Badizadegan (Nov 18, 2012)

Shoot Jpeg if you want the image to irreversibly suck. 

Shoot raw if you want the image to reversibly suck.


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## RinaldiPhotos (Nov 18, 2012)

Ok, I have always been under the interpretation that I can only shoot Raw or JPEG with my T2i, but I have seen people in this thread mention that you can shoot both.  Can anyone briefly tell me how I would go about doing both?


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## Ysarex (Nov 18, 2012)

RinaldiPhotos said:


> Ok, I have always been under the interpretation that I can only shoot Raw or JPEG with my T2i, but I have seen people in this thread mention that you can shoot both.  Can anyone briefly tell me how I would go about doing both?



It's available from your camera menu -- RAW plus JPEG. In which case you'll save two files on the card for each photo taken.

Joe


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## Ysarex (Nov 18, 2012)

AlexanderB said:


> KmH said:
> 
> 
> > I too shot both, but mostly I shot Raw.
> ...



I haven't met a camera algorithm that didn't suck.

If the scene lighting is ideal and the exposure correct, the camera software can be counted on to process the raw data to a mediocre result. I can always do better. The minute the lighting starts to deviate from ideal and becomes at all difficult the camera software starts to really suck. That gives you two expected outcomes from the camera software: 1. mediocre and 2. really suck -- averaged together to just suck.

Suck is not a very precise term and could become a point of contention. So for clarity then, my measure of "suck" for the software in the cameras is; can it do the job as well as I can. If it can't it sucks.

(I swore I was going to stay out of this thread! One beer and all my resistance just caves!)

Some notes: For the sake of clarity what this question is really asking is how do you arrive at a finished RGB photo. Do you rely on the software in the camera or do you rely on the software in your computer or do you rely on yourself?

1. Raw capture in camera to camera image processor to RGB JPEG.
2. Raw capture in camera to computer to automated batch processed (using raw converter) RGB photos.
3. Raw capture in camera to computer to photographer processed (controlling raw converter) RGB photo.

There are appropriate circumstances for all three of those options. If I were taking a lot of photos and selling them I'd select option 1 or 2 because time is money and I'd want to make as much money as possible -- haven't yet figured out how to make time. The photos of course would have to be good enough to satisfy my clients.

Since I'm not selling lots of photos I have enough time to get the very best result. In that case I chose option 3 since I'm better at processing a photo than the software in the cameras.

Raw has a whole lot more "editing headroom" in the hands of a skilled photographer versus in the hands of a sucky software algorithm. The algorithm lacks flexibility and any ability to adapt to unique characteristics of a specific image -- a good explanation for why it sucks. That flexibility and adaptability possessed by the photographer equates to "editing headroom." The photographer can adjust the conversion process before the final commitment to compressed 8 bit -- that's headroom. Once that final commitment is made the headroom is gone.

Joe


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## Ysarex (Nov 18, 2012)

AlexanderB said:


> KmH said:
> 
> 
> > Today's digital cameras make 12-bit depth (4096 discrete colors per color channel, as defined by colormetric interpretation of the Bayer array) or 14-bit depth (16,384 discrete colors per color channel, as defined by colormetric interpretation of the Bayer array).
> ...



It's not about "fixing" photos it's about processing to an intended outcome when, photographing under natural light conditions, it's not possible to alter the lighting. That's why they invented the zone system back in the good old days. Today we have 14 bit depth captures and you sure can pull up a lot of data from the low end -- a lot more than will be in the camera (sucky algorithm) JPEG.

Here's an example. You'll note from the EXIF data that I dialed in a -.3 EC when I took this photo. I didn't want to blow the highlights in the sky. In the camera JPEG the sucky algorithm sure enough has clipped the red channel and blocked the shadows. This processed by me from the raw file where I had lots of editing headroom:




Here's the camera JPEG full-res if you'd like to demonstrate that it can be adjusted to match.

wetland

I knew what I was doing when I took that photo and I knew what I intended as a final result. I knew I could get it from a raw capture just as surely as I knew that no sucky camera software could do anything with this scene other than crash and burn.

Joe


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## RinaldiPhotos (Nov 18, 2012)

Ysarex said:


> RinaldiPhotos said:
> 
> 
> > Ok, I have always been under the interpretation that I can only shoot Raw or JPEG with my T2i, but I have seen people in this thread mention that you can shoot both.  Can anyone briefly tell me how I would go about doing both?
> ...


Thanks a bunch, Im gonna stock up on 32's on Black Friday.


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## Garbz (Nov 19, 2012)

AlexanderB said:


> Heavily underexposed RAW image contains 14 bit of trash and nothing will help it. I will repeat that RAW is useful if you know you want to use own conversion algorithm, that is the main its application. You cannot fix underexposed photos in post-process even if you use RAW. For small amount of exposure correction (-/+ 1 stop) jpeg will do just fine as RAW.



My good friend you need to learn something about how digital images are processed. Firstly you need to stop with this idea of "conversion algorithm". Just use the word settings. If shoot a photo on my Nikon camera in JPEG, and in RAW, and then adjust the brightness of the RAW I am still using the same "algorithm" in the conversion, but very different settings and depending on these settings the RAW file may not be able to look anything like a JPEG. 

Secondly the idea of gamma is worth very little to the discussion. Gamma can be adjusted in post processing at any time. Lightroom for instance doesn't apply the corrective gamma curve until after it's done all other modifications to the image. Personally I work with linear data when editing any astronomy photos, it makes it easier to separate luminance and colour channels, but ultimately changes nothing for  how the final image will look. The only time a gamma correction has any negative effect on data is if two different values before correction result in the same value afterwards, and that is the direct result of a low bit-depth.

Enter JPEG.

You need to let go of the idea that there's such a thing as 14bits of trash. There's no such thing as trash bits. If a bit represents a photon that has hit the sensor than that bit contains data, even if that data is below the noise floor it is still data and thus still useful in post processing. The only useless data is all zeros or all ones. Because of your aforementioned gamma correction a picture can visibly be extremely dark yet still contain an enormous amount of data above the zero point. ... if you have the required bit depth to retain that data. JPEG can't. It's 8bit. Your issue is not one of RAW vs JPEG, it's one of 14bit data vs 8bit data. That is 16384 discrete values per channel vs 256 values, and that's a massive difference as people have already shown by example. 

If you're making a tiny adjustment to an image will you notice a difference between the two? Unlikely. But then life doesn't always provide you with the perfect exposures allowing tiny adjustments does it? We live in the world of HDR and extreme dynamic range images. The notion that we purchase a $1000+ camera only to throw away some of this is absurd. Oh by the way part of your "conversion algorithm" in the camera typically trashes some of the highlights and shadows in an attempt to make a pleasing generic contrasty image. The result is that highlight recovery is impossible at this point. If you've slightly blown a highlight than the difference between RAW and JPEG even with a -0.1 exposure adjustment can be night and day.


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## AlexanderB (Nov 19, 2012)

Garbz said:


> My good friend you need to learn something about how digital images are processed. Firstly you need to stop with this idea of "conversion algorithm". Just use the word settings.


If you use Nikon software to convert your RAW files, yes, it comes down to choosing "settings". There are also myriads of other ways to produce final jpeg from raw data and gamma correction is just one of them. Different tonemapping algorithms are an actively developing topic. 



Garbz said:


> There's no such thing as trash bits. If a bit represents a photon that has hit the sensor than that bit contains data, even if that data is below the noise floor it is still data and thus still useful in post processing. The only useless data is all zeros or all ones.


If you've underexposed your image 4 stops you've produced approximately 4 bits of trash per channel. Not every bit recorded in Raw file is usefull. Actually low light areas of an image do not need that much bits to record the number of photos hit the pixel and this fact is used in Nikon's "lossy" NEF format. 

So back to 14 bits of RAW vs 8 bits argument. I will repeat once more: comparing these bits is meaningless, because JPEG bits are gamma corrected values and RAW bits are linear values. Gamma correction helps JPEG retain the valuable information packed into less bits. That's all I wanted to say. 

To make it clear I am not 'for JPEG' or 'against RAW'. I believe RAW is useful for critical work and JPEG is more convenient where IQ is not that critical (family pics etc.)

A bit of my background: I happen to work on photo software as an image processing algorithm engineer but I'm not a photography professional (not selling pictures), just an enthusiast. At home I even do not own Photoshop or Lightroom/Aperture. I've bought my first digital camera in 2001. Using mostly Nikon, currently D700.


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## Helen B (Nov 19, 2012)

AlexanderB said:


> At home I even do not own Photoshop or Lightroom/Aperture. I've bought my first digital camera in 2001. Using mostly Nikon, currently D700.



It might be worth downloading an evaluation copy, and then comparing the difference between 'exposure' adjustments to JPEG and raw files.


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## Dikkie (Nov 19, 2012)

I used to shoot JPEG first when I had my first digital camera. 

But then I tried RAW afterwards, I thought it would be lots of work to edit and get the settings right, but it's still not so time consuming as I thought.

Without going technically, because I'm a quite simple average user, I noticed that I can do LOTS more with RAW what I couldn't with JPG. 
Certainly adjusting the white balance and exposure. 
I'm not going back to JPEG ever...


Maybe people who believe in JPEG aren't that detailed that they have no need for RAW? Or maybe the haven't experienced RAW enough to get a good understanding on imaging?


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## AlexanderB (Nov 19, 2012)

Helen B said:


> AlexanderB said:
> 
> 
> > At home I even do not own Photoshop or Lightroom/Aperture. I've bought my first digital camera in 2001. Using mostly Nikon, currently D700.
> ...



Believe me I have enough of this (image processing) at the day job. I do not underestimate the value of raw files, my point was that it's pointless comparing bit counts in linear gamma corrected ranges.

But thinking about buying aperture as my photo collection grows too fast


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## AlexanderB (Nov 19, 2012)

Ysarex said:


> Here's an example. You'll note from the EXIF data that I dialed in a -.3 EC when I took this photo. I didn't want to blow the highlights in the sky. In the camera JPEG the sucky algorithm sure enough has clipped the red channel and blocked the shadows.
> 
> I knew what I was doing when I took that photo and I knew what I intended as a final result. I knew I could get it from a raw capture just as surely as I knew that no sucky camera software could do anything with this scene other than crash and burn.
> 
> Joe



Hi Joe, surely nothing will recover a poorely exposed JPEG with clipped channels. But I did not say that! My points were: 14 bit linear bits not comparable to 8 bit gamma corrected 2) poorly exposed raws are not recoverable 3) properly exposed jpegs have some headroom for small fixes.


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## TCampbell (Nov 19, 2012)

There are two issues with JPEG.

Any camera or algorithm will probably do a good job with easy exposures.  I'm referring to well-exposed shots that don't require much dynamic range.  JPEG struggles when the shots do require a lot of dynamic range.  For example... JPEG is a terrible format if you are shooting landscapes with 5+ stops of dynamic range in the image.

If we think of the ranges as "#1  Very dark", "#2 Dark", "#3 Mid-tones", "#4 Light", & "#5 Very light" then you can expect JPEG to do a great job with ranges 2 through 4.  It'll struggle with #1 and #5.  

JPEG tends to compress detail in shadow and highlight because the algorithm doesn't think human vision would notice it anyway.  If the image didn't require adjustment then the algorithm would probably be right... we wouldn't notice it.  This falls on it's face when the image DOES require adjustment and you discover the detail is missing; that same detail that was definitely there with you and your camera when you were capturing the image.

Bit-depth is another problem.  JPEG only has 8 bits per color channel.  In theory, JPEG can represent 8 stops since it has 8 bits.  The problem is that the lowest bits have no tonality... you definitely wont be happy with the lowest 2 bits (which can only describe 4 possible values) and when you add the third bit you get 8 possible values... which is also pretty bad.  It isn't until you get to the 4th bit that you can describe 16 possible values and have any enough tonality within the stop to avoid looking pixelated.  That leaves you with only about 5 "usable" stops of dynamic range in a JPEG.

Now that you've got 5 "usable" stops (which is all that most cameras are good at anyway), you've got the problem with JPEG compression trying to eliminate detail your eye probably wouldn't notice so that it can save disk space.  So now you're down to about 4 "usable" stops.

RAW, on the other hand, has 14 bits per channel.  To keep things fair... we decided that the lowest 3 bits weren't really useful as stops so we'll discard them.  That leaves us with 11 stops worth of usable dynamic range that would actually look decent.


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## Ysarex (Nov 19, 2012)

AlexanderB said:


> Ysarex said:
> 
> 
> > Here's an example. You'll note from the EXIF data that I dialed in a -.3 EC when I took this photo. I didn't want to blow the highlights in the sky. In the camera JPEG the sucky algorithm sure enough has clipped the red channel and blocked the shadows.
> ...



I didn't say you did.



AlexanderB said:


> My points were: 14 bit linear bits not comparable to 8 bit gamma corrected 2) poorly exposed raws are not recoverable 3) properly exposed jpegs have some headroom for small fixes.



I've been reacting to these statements of yours: "The only reason to shoot raw if you want to do gamma correction using your algorithm (software), not one in camera. If raw have more "editing headroom" then the in camera algorithm sucks, but usually it is not the case."

And, "It was my point that 8-bit gamma corrected values store almost all the information actually useful from RAW file (in case if jpeg codec in camera works properly)."

You were reacting to Keith's post where he noted that we have a lot more "editing headroom" with a raw capture than we do with a JPEG. That when the JPEG is created by the in camera algorithm that "headroom" is discarded and any further editing access is severely limited.

My point is Keith is correct. There's a huge amount of additional editing headroom in a raw file. You're saying that's not the case as long as the camera JPEG codec works properly -- as long as the in camera algorithm doesn't suck which you say it usually doesn't. And I'm saying the in camera algorithm usually does suck. Under ideal lighting conditions the in camera algorithms produce mediocre results acceptable to the general public. But ideal lighting occurs infrequently when working with natural light and as soon as the lighting is no longer ideal the in camera algorithms quickly degrade from mediocre to suck. The JPEG that then results is typically damaged beyond repair (as in my example). But with the huge amount of editing headroom available in the raw capture the photo can be processed successfully and the damage that would be done by the sucky camera algorithm can be avoided.

You were suggesting that it's not really that advantageous to shoot raw as long as the in camera algorithms don't suck which you say they usually don't. I'm saying they usually do suck and the damage they do can be avoided by manual processing and taking advantage of all that extra editing headroom available in the raw file.

Joe


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## Helen B (Nov 19, 2012)

AlexanderB said:


> Helen B said:
> 
> 
> > AlexanderB said:
> ...



My apologies, your previous comments seemed strange for someone who was used to processing raw files. They still do seem strange, and they contradict experience.

It may not be straightforward to compare bit depth between a linear-encoded file and a gamma-corrected one, but that doesn't make it pointless. It is perfectly possible, and meaningful.


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## Dikkie (Nov 19, 2012)

Ysarex said:


> I didn't say you did.


But IF he did, which he didn't, what would YOU do ?
I mean, what would you have done in his place, even if he or you didn't?


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## AlexanderB (Nov 19, 2012)

Ok, ok guys and gals. My initial reaction was about the statement that '80% color information is thrown away'. For properly exposed photos it is not correct, the most of information is preserved (and partially due to range compression by gamma correction). Raw definitely has more headroom for editing than JPEG. That's out of the question. The question is how much more?  JPEG is ok for processing if properly exposed (at least not clipped) in the first place and in-camera codec is good (which is not the case in some cameras, but now it's rare). It is far more easy with raw to get the best results possible. But it's not impossible with jpeg too, but requires much more skill. That's it. For, example, for my image processing app (if you curious, it's called PanoEdit) the number one priority was support of raw files. Without it was just not useful for too many people.


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## Ysarex (Nov 19, 2012)

AlexanderB said:


> Ok, ok guys and gals. My initial reaction was about the statement that '80% color information is thrown away'. For properly exposed photos it is not correct, the most of information is preserved (and partially due to range compression by gamma correction). Raw definitely has more headroom for editing than JPEG. That's out of the question. The question is how much more?  JPEG is ok for processing if properly exposed (at least not clipped) in the first place and in-camera codec is good (which is not the case in some cameras, but now it's rare). It is far more easy with raw to get the best results possible. But it's not impossible with jpeg too, but requires much more skill. That's it. For, example, for my image processing app (if you curious, it's called PanoEdit) the number one priority was support of raw files. Without it was just not useful for too many people.



I understand your reaction to the 80% figure and further understand what you're trying to say about the gamma curve application to the raw data. The applied curve compresses the tonal information and as such makes use of a lot of the recorded data. But I'm still going to have to say no to this assertion; "JPEG is ok for processing if properly exposed (at least not clipped) in  the first place and in-camera codec is good (which is not the case in  some cameras, but now it's rare)."

This assertion requires further qualification. In a studio it's possible to control the lighting contrast. One could in fact learn to adjust the lighting contrast to take best advantage of a camera's JPEG processing software. That ability to control the lighting becomes far more difficult and/or impossible in natural light. Your assertion calls for proper exposure as an assumption. So let's do a for instance:

The photo I posted earlier was backlit. What would have been a proper exposure? The camera JPEG processing software clipped the red channel in that photo and it also clipped all three channels on the low end. So I didn't have a proper exposure. I needed to do what? Increase the exposure so the shadows wouldn't be blocked. Then I'd have a proper exposure right? Wait a minute! The highlights in the red channel were already clipped. If I increased the exposure so the shadows wouldn't block up then the highlights would clip even worse. How do I get a proper exposure then? Forced to rely on the software in the camera, all possible exposures of that scene would produce failure -- "properly exposed" wasn't an option for the sucky software in the camera. But that *was* a proper exposure for me as I processed the raw data.

Your assertion has to read: JPEG is ok for processing if *an ideally lit scene is* properly exposed (at least not clipped) in  the first place and in-camera codec is good (which is not the case in  some cameras, but now it's rare). I'll reluctantly let that go, but....

I don't allow my students to refer to adjusting and/or correcting camera generated JPEGs as editing or processing. I let them do it, in fact I teach them how to do it but, I insist they use the term repair. The processes of assigning a color space, reducing to 8 bit and compressing the data are finishing steps -- you do then when your finished editing. If you go back after you're finished it can only mean you need to fix a screw up. Once the book has gone to press there's no more editing.

Joe


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## panblue (Nov 19, 2012)

For small amount of exposure correction (-/+ 1 stop) jpeg will do just fine as RAW.[/QUOTE]

I agree, however some people are working with raw captures to overcome shortcomings in the JPEG processing of certain cameras, which reduce detail.


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## AlexanderB (Nov 19, 2012)

Ysarex said:


> This assertion requires further qualification. In a studio it's possible to control the lighting contrast. One could in fact learn to adjust the lighting contrast to take best advantage of a camera's JPEG processing software. That ability to control the lighting becomes far more difficult and/or impossible in natural light. Your assertion calls for proper exposure as an assumption. So let's do a for instance:
> 
> The photo I posted earlier was backlit. What would have been a proper exposure? The camera JPEG processing software clipped the red channel in that photo and it also clipped all three channels on the low end. So I didn't have a proper exposure. I needed to do what? Increase the exposure so the shadows wouldn't be blocked. Then I'd have a proper exposure right? Wait a minute! The highlights in the red channel were already clipped. If I increased the exposure so the shadows wouldn't block up then the highlights would clip even worse. How do I get a proper exposure then? Forced to rely on the software in the camera, all possible exposures of that scene would produce failure -- "properly exposed" wasn't an option for the sucky software in the camera. But that *was* a proper exposure for me as I processed the raw data.
> 
> ...



For a proper exposure I refer to an exposure that allows to gather as much light as possible for a given subject just to improve s/n ratio of the image. If you know your subject well you can program your camera not to clip channels, even in a difficult lighting. All modern cameras allow to alter default curve using in-camera settings such as contrast, saturation etc. But I'm not insisting one way is better than another. For a difficult editing in post processing, like panorama stitching, raw is indispensable.


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## unpopular (Nov 20, 2012)

the in-camera settings are typically not nearly sufficient, except in very high-end gear like the Dx series. And still likely represent post-process adjustments, that is, after the gamma encoding has been executed. It makes much more sense to adjust gamma at the start of the RAW development pipeline, rather than after.

In a typical ETTR workflow, adjustments are made to essentially de-compensate to some extent initial gamma encoding....


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## Garbz (Nov 20, 2012)

AlexanderB said:


> The question is how much more?



Look the maths is on your side in this argument. Practicality is NOT. Nearly all post processing attempt to somehow recover shadow detail from the contrasty images our camera manufacturers have decided we all should like. This is largely due to the fact that blown highlights look BAD. The idea to get a good image is to shoot to the right, i.e. make the image as bright as possible without blowing the highlights and then pick the correct colour in post. However due to the very contrasty nature of ... well nature, the vast majority of images end up either a) under exposed in an attempt to keep highlights from blowing, or b) properly exposed and requiring some level of highlight recovery due to a clipped channel. One of these sucks for JPEG and the other is impossible.

There is one and only one use for JPEGs, and that's when you're desperately low on disk space. You can make a JPEG at any time after the fact, but you can't recover the data once it's gone, something you may want to tell grandma when you accidentally over exposed her hair during your family portrait. You spend thousands on your camera, why cripple it?


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## AlexanderB (Nov 20, 2012)

Damn it! Topics like these are always not fruitful. RAW vs JPEG is wrong question. I use both. Just sometimes tinkering with Nikon View NX (I'm the only one here using this for RAW? Everyone here seems to use Lightroom/Aperture) is not worth the effort for simple pictures or if jpeg is good enough for the purpose. If in doubt I just switch to RAW.


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## Ysarex (Nov 20, 2012)

AlexanderB said:


> Ysarex said:
> 
> 
> > This assertion requires further qualification. In a studio it's possible to control the lighting contrast. One could in fact learn to adjust the lighting contrast to take best advantage of a camera's JPEG processing software. That ability to control the lighting becomes far more difficult and/or impossible in natural light. Your assertion calls for proper exposure as an assumption. So let's do a for instance:
> ...



In principle yes, in practice not even in the ballpark. At this stage in the technology that option merits only a definitive NO.



AlexanderB said:


> All modern cameras allow to alter default curve using in-camera settings such as contrast, saturation etc. But I'm not insisting one way is better than another. For a difficult editing in post processing, like panorama stitching, raw is indispensable.



Those controls available on modern cameras can be graciously described as crude.

Joe


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## Ysarex (Nov 20, 2012)

AlexanderB said:


> Damn it! Topics like these are always not fruitful.



Sure they are. They provide useful information.



AlexanderB said:


> RAW vs JPEG is wrong question. I use both.



I pointed that out in my first post in this thread. The question should be: do you rely on automated software to process the raw capture data or do you manually do that processing using a raw converter. And I'm going to continue to maintain that the automated software in the camera does a mediocre job and, when faced with difficult lighting, it does a poor and usually unacceptable job. I can always do better than the automated software in the camera and I believe that better is just that -- better.



AlexanderB said:


> Just sometimes tinkering with Nikon View NX (I'm the only one here using this for RAW? Everyone here seems to use Lightroom/Aperture) is not worth the effort for simple pictures or if jpeg is good enough for the purpose. If in doubt I just switch to RAW.



Part of our difference here I suspect has to do with degree. You just used the description "good enough." I understand that and I find good enough acceptable in many aspects of my life. My wardrobe is good enough for me even though my wife prefers not to be seen with me in public. But when it comes to photography "good enough" is never good enough for me.

I'm only slightly familiar with View NX since I'm not a Nikon owner but I do encounter it via my students who have Nikons. I don't use LR or Aperture as I don't require their DAM capabilities. I have Canon's DPP (similar to View NX) but I also have and use Adobe ACR, Capture One, Photo Ninja and Raw Therapee. I switch between those converters in order to get the very best result. So I'm using 5 different raw converters although most of my work goes through Capture One and now Photo Ninja.

Because I teach about 25 college students each semester I'm very familiar with the capabilities of all the different cameras and their processing software and as noted the leading raw conversion software. I get everything in class from P&S cameras to one of my students this semester just purchasing a 5DmkIII. Which is to say my observations are founded on considerable hands-on experience.

Joe


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## AlexanderB (Nov 20, 2012)

Ysarex said:


> In principle yes, in practice not even in the ballpark. At this stage in the technology that option merits only a definitive NO.
> 
> Joe



Hi Joe, it's starting a bit deviating from topic, but this one is interesting to me. In my experience with working with images produced by digital cameras I see it with my own eyes: the best images are that ones have that gathered the most of the light possible for a given subject, with sensitivity set just a hair not clipping the sensor. Where I'm wrong? What is a proper way to exposure? May move to a new thread?


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## unpopular (Nov 20, 2012)

There is no such thing as "proper exposure" or "ideal lighting". I wish that people would get this concept out of their heads. It's not something that is measurable.


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## AlexanderB (Nov 20, 2012)

unpopular said:


> There is no such thing as "proper exposure" or "ideal lighting". I wish that people would get this concept out of their heads. It's not something that is measurable.


The signal/noise ratio is pretty measurable, and exposure directly affects it. The more signal/noise ration the more 'IQ' you can squeeze from your raw file. I definitely recommend this read Noise, Dynamic Range and Bit Depth in Digital SLRs


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## unpopular (Nov 20, 2012)

^^ oh. trust me. I am *very* familiar with this, and spend a good amount of time thinking about it. But, I do agree. so is clip. 

There are measurable qualities relating to exposure, but "proper" exposure isn't something that can be measured. It's a subjective quality. If you maximize signal, most people - perhaps inaccurately - will determine the photograph is "over exposed", even though clipping isn't present.


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## Ysarex (Nov 20, 2012)

AlexanderB said:


> Ysarex said:
> 
> 
> > In principle yes, in practice not even in the ballpark. At this stage in the technology that option merits only a definitive NO.
> ...



Absolutely -- I completely agree. Unpopular earlier mention ETTR. The goal in exposure should be to expose just as you say; a hair from not clipping the sensor. You are not wrong. But in light of the rest of this thread that's very interesting because that exposure practice all but guarantees clipped highlights in the camera JPEG if the subject is normal to high contrast. Putting it another way: I know I have a good exposure when the camera histogram indicates clipped highlights.

Joe


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## Ysarex (Nov 20, 2012)

unpopular said:


> ^^ oh. trust me. I am *very* familiar with this, and spend a good amount of time thinking about it. But, I do agree. so is clip.
> 
> There are measurable qualities relating to exposure, but "proper" exposure isn't something that can be measured. It's a subjective quality. If you maximize signal, most people - perhaps inaccurately - will determine the photograph is "over exposed", even though clipping isn't present.



I understand what you're saying -- been here before. You maximize signal (which is measurable) and then you process the data for the photo you want and a photo that doesn't appear poorly exposed. By maximizing the signal (exposure) you get the best final result after processing.

Joe


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## Ysarex (Nov 20, 2012)

Ysarex said:


> unpopular said:
> 
> 
> > ^^ oh. trust me. I am *very* familiar with this, and spend a good amount of time thinking about it. But, I do agree. so is clip.
> ...



This is again the point I've been pounding on here. When you say most people will determine the photo is overexposed; I say, what photo? The camera JPEG? That's the point. But when we're done processing the raw capture it won't appear overexposed. It will be the best it can be.

Joe


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## unpopular (Nov 20, 2012)

Yes, exactly. "over exposure" does exist, any region which is clipped is over exposed. but aside from that an image is either "too light" or "too dark", which is a subjective standpoint.

This came to me because when I was a know-it-all teenager I approached a grad student, and complained that his thesis was "under exposed". Naturally, he didn't appreciate a snot-nosed 17-year old undergrad with a few years' experience telling him his photos sucked, and defended it, stating that all the tonal range is present. It clicked then, that my problem with the photograph was not something technical, but one of personal preference - in fact, there were no plugged up shadows, but rather it was simply rendered darker than I would have preferred it.


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## AlexanderB (Nov 20, 2012)

Ysarex said:


> Ysarex said:
> 
> 
> > unpopular said:
> ...



Thanks God, we came to some consensus and understanding here.


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## skieur (Nov 28, 2012)

I use both.  Sometimes RAW is good to have as "insurance" in difficult shooting situations.  In other cases, raw is unnecessary and time consuming.

skieur


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