Why RAW, TIFF and Jpeg?

[Blu-By-U]

Extract from another thread. As a newbie to photography, would like to know when and why for the different formats offered in the camera.

A bit from my own recent holiday, I started in RAW but ran out of storage space after 3 days...then I switch to JPEG and limiting myself in using RAW.

The basic, that we all know, is that we loose details Jpeg with each save. irregardless of the compression. RAW, is large file size and sometimes slow in writing to memory card. Sometimes we can actually lose a shooting moment because the camera is flushing the memory. TIFF, actually i have never shot in this format. When should we use this and why.

Experts, please share you views. and NO FLAMES please.

[selamatlzh]

I am not an expert here. But this is just my practise.

The first few months I got my camera, I shot all my photos in jpeg. But I have been shooting raw for the last 1 year or so. RAW allows me to capture all he details in the photograph which allows me to fine tune the photo with photo editing tools. I did not buy the latest photoshop that allows me to work on the RAW files directly. Therefore I save my "favourite" photo in TIFF from master the edit the file with photo editing software. While the rest of photo with minor adjustment done on Master i save them in jpeg file.

Why TIFF ? I use it for 2 reasons. Prinitng and portability. I have tried printing a jpg and tiff files in 8x10 and compare them side by side, you will loose the details in jpeg which is why i keep the files in TIFF. Though It is a pain to bring a tiff file to the lab but at least they are able to open and print the files directly.

Pesonally I dont believe in getting big CF card as they are expensive and will never be enough for RAW storage. Therefore I bought an external storage to keep all my files.

[uginz]

ever since i got a prosumer cam with RAW capability i've never shot in jpeg ever since.
why? coz RAW is like the digital equivalent of negatives in film. the actual image that the camera records. so all the image information is there.

also with RAW you can do alot preprocessing work that makes your postprocessing much easier, eg, white balancing, exposure, saturation. why do this with RAW? coz you can do all this without losing any information unlike when you do it with Jpeg on photoshop. for instance, you over expose and image which get blown out. with raw you can rescue this area.

Tiff format i believe as similar abilities as RAW but you have do it in photoshop. also Tiff takes up huge amts of memory compared to RAW. so, why use a format that has similar capabilities but takes up huge amt of space.

lastly, RAW is the way to go with higher end cameras so as to maximize your camera's capability. same logic, why use an inferior format when you have much superiour format availiable? if speed is a problem, use fast writing cards. if space is problem, buy more cards, i believe 1gig cards now are very cheap compared to a year ago.

[leejay]

*.tiff format is not meant for normal photography. It is used for face recognition or target detection in machine analysis of pictures. Target detection systems on fighter planes use *.tiff images from satellites. Face recognition systems also reads face images in *.tiff format.

[Mikefellh]

For my usual shooting I shoot in RAW+JPG...when I want quick images I have the JPEGs, and when there's something worth processing I'll process the RAW file. For me speed/capacity isn't an issue as I use a 4gig Extreme III card which is the fastest card for the E-300/500 (and probably later E's).

[optimage]

I shoot RAW + Jpeg basic. Raw is better for fine tuning and post processing while Jpg is better for quick previews and online sharing without the time consuming conversion process. After investing so much in the best lenses and camera, why limit yourself to 8-bit JPG when you can have 12-bit RAW. Tiff is definately overkill because the file size is just too big. I carry 7GBs worth of CF storage just to be sure I never run out.

[drakon09]

Originally Posted by leejay *.tiff format is not meant for normal photography. It is used for face recognition or target detection in machine analysis of pictures. Target detection systems on fighter planes use *.tiff images from satellites. Face recognition systems also reads face images in *.tiff format.

A bit overstating .tiff formats here.

A .tiff file is basically an uncompressed image. For large (poster size upwards), high quality, high resolution professional prints, .tiff is recommended.

[Blu-By-U]

Thank you..Me really blurr on these issues here.

Raw and Jpeg settled Tiff is still unclear. If RAW and Tiff is almost similar, RAW can convert to Tiff without much problem, but RAW files are smaller than Tiff ... aaaggghhhh!!!!!

[drakon09]

To keep things simple, a .tiff contains more information than a .orf, that's why .tiff files are larger.

[Hoky]

Taken from Bruce Fraser:

When you shoot JPEG, a raw converter built into the camera carries out all the tasks listed earlier to turn the raw capture into a color image, then compresses it using JPEG compression. Some cameras let you set parameters for this conversion—typically, a choice of sRGB or Adobe RGB as color space, a sharpness value, and perhaps a tone curve or contrast setting. Unless your shooting schedule is atypically leisurely, it’s difficult to adjust these parameters on an image-by-image basis, so you’re locked into the camera’s interpretation of the scene.

JPEGs offer fairly limited editing headroom—large moves to tone and color tend to exaggerate the 8-by-8-pixel blocks that form the foundation of JPEG compression—and while JPEG does a decent job of preserving luminance data, it applies heavy compression to the color data, which can lead to issues with skin tones and gentle gradations when you try to edit the JPEG.

When you shoot raw, however, you get unparalleled control over the interpretation of the image through all the aforementioned aspects of the conversion. When you shoot raw, the only on-camera settings that have an effect on the captured pixels are the ISO speed, the shutter speed, and the aperture setting. Everything else is under your control when you convert the raw file—you can reinterpret the white balance, the colorimetric rendering, the tonal response, and the detail rendition (sharpening and noise reduction) with a great deal of freedom. Within limits (which vary from one raw converter to another), you can even reinterpret the exposure compensation.

[wind30]

Originally Posted by drakon09 To keep things simple, a .tiff contains more information than a .orf, that's why .tiff files are larger.

?? how can the tiff has more information than the raw?

tiff is mainly for photoshop work. You can develop in 16 bit tif where you can apply all your photoshop filters, masking, etc, without losing any information. Much easier to work in 16 bit tiff than jpeg (too much info lost) or RAW (too infexible, cannot apply filters, etc).

[Mikefellh]

Originally Posted by Blu-By-U Raw and Jpeg settled Tiff is still unclear. If RAW and Tiff is almost similar, RAW can convert to Tiff without much problem, but RAW files are smaller than Tiff ... aaaggghhhh!!!!!

While uncompressed, TIFF files are PROCESSED by the camera, and limited to the settings the camera is set to while the picture was taken...with RAW you can change white balance, exposure compensation, WITHOUT losing data. Any time you are editing a processed image, you are losing data.

Originally Posted by wind30 ?? how can the tiff has more information than the raw?"

Some file formats are sloppy in the way the data is saved. For instance I can create a really sloppy image format that goes like this:

This is pixel one's colour "45"
This is pixel two's colour "139"
This is pixel three's colour "78"
etc.

You can see with all that extra information that has to be stored for each pixel a file will be a lot larger. Now that is an extreme, FICTIONAL example...but it's just to show RAW isn't always largest.

And FYI, the Olympus has on it one of the smallest JPEG compressions vs. other manufacturers including Canon and Nikon...their best JPEG image quality is like our HQ image quality, so our SHQ is superior for quality.

[chainsmoker]

Mike, thanks for the info.

Wat abt DNG format, izit good enough for manufacturers to adopt this open standard oneday?

[Mikefellh]

Originally Posted by chainsmoker Wat abt DNG format, izit good enough for manufacturers to adopt this open standard oneday?

The question is, do they want to? First of all the only programs out there that read DNG are from Adobe. Second, manufacturers would have to give up their secrets to Adobe in order for Adobe to develop DNG firmware for that particular body...not really an open standard.

[cjtune]

Very enlightening thread about RAW. Keep it up, guys!

[splim]

I remember saw it somewhere, the .orf file has some form of lossless compression, that's why it is a little bit smaller, but don't know where I saw it now.

[ykkok]

CCD is colour blind, and each pixel only handles luminance (brightness) signal, filtered by either R, G or B. And that's what captured in RAW format. With interpolation, full spectrum of RGB per pixel is reproduced.

Why uncompressed TIFF is larger than .ORF is because it carries full RGB values per pixel vs .ORF which carries one colour each. You guys may find better explanation elsewhere on the web as I can't really explain it properly.

TIFF files was popular because it was one format that carries more 'info' than 8-bit JPEG and it's also a format that can be opened by virtually any post-processing applications during those days. But now, with so many newer software capable of opening propietory RAW format (by frequent online updates), to me, shooting and saving in TIFF is not really practical anymore. Anyway, TIFF is generated from RAW in-camera.

[Mikefellh]

Originally Posted by splim I remember saw it somewhere, the .orf file has some form of lossless compression, that's why it is a little bit smaller, but don't know where I saw it now.

Not the Olympus. You probably saw that some other brands use lossless compression, and someone was wondering why Olympus RAW files were so much larger than the competition. Personally I don't know why Oly wouldn't compress their RAW file (write speed of a large file vs. compression time).

[radi9red]

In my perspective >> Raw is simply a unprocessed version of a digital photo, which some people named it digital negative. Raw can be post-processed to generate 8 or 16 bit output. Outputs can be in Jpeg (8 bit with compression levels) or Tiff (8 bit / 16 bit).
Technically if you shoot raw and output to a compressed jpeg , the output quality is very close to shoot from camera Jpeg directly.

There are some people who think that Raw can perform more tweak and modifications and salvage picture. The answer is both yes and no .. Shooting RAW, does give you an unprocessed and you can edit exposures settings etc.. and then processed it. However, it DOES not meant it can fixed BAD exposures or totally BAD white balance. It can only "tweak" or adjust to a certain levels.

Thus, when you shoot raw, the fundamentals of photography must still be observed.

Disadvantages of raw > Large filesizes, try shooting 500 photos of wedding shots in raw. the conversion and editing is gonna kill you. You need to setup workflow process for batch processing which might be quite technical for most people.

Myth of Raw >> People think can only raw can correct wrong exposures or wrong white balance.. this is a misconception. Jpeg and tiff can also do that using the proper image edition software.

Advantage of Processing raw over jpeg / tiff > RAW , unprocessed and after tweaking it.. you finalize and output in TIFF .. If you were to use jpeg and TIFF and process it and tweak it and save it .. there will be some "image data" loss or pixels that are modified or added based on software algorithium. However, these losses might not be evidental to human eyes perception. Thus think about it .. a compresses file has already discarded some pixel data.. the more you tweak a compressed imagae (jpeg), more data get changed from the original..

Why then people wanna shoot jpeg or tiff ??

Tiff >> High reso , uncompressed. YOu need the "pixel data" for large prints at high dpi.

Jpeg >> Small file size, fast to review and print and edit. Most DSLR jpeg output has image / colours and contrast post processing thus the colours might look "vibrant". Just think about sony point and shoot vibrant colours produces..

Summary >> If the intention for your photos are for monitor display purposes.. you cannot tell much differences from a RAW output or tiff / jpeg output.. If its meant for professional work submission or for large format printing... you better have the original uncompressed (tiff or Raw) cos no one would want a mona lisa photo with compressions (lesser pixel data) in jpeg mode for large printing..

[Mikefellh]

Originally Posted by radi9red In my perspective >> Raw is simply a unprocessed version of a digital photo, which some people named it digital negative. Raw can be post-processed to generate 8 or 16 bit output. Myth of Raw >> People think can only raw can correct wrong exposures or wrong white balance.. this is a misconception. Jpeg and tiff can also do that using the proper image edition software.

Actually not a misconception...as I said above you can correct JPEG or TIFF BUT you are losing data when you do so. As RAW is just the unprocessed RAW bits as seen from the sensor and has no white balance applied (white balance is only applied when processing an image in camera), you can apply any white balance you want without losing data. You are doing the processing that would have been done in the camera, except you have the ability to experiment with the same shot over and over again without having to take the same shot over and over again.