[MD Optofonik]

Is a camera that only outputs JPG images actually actually capturing RAW images and internally processing them before output? Or, do these cameras forgo any sort of RAW file capture altogether?

[clackers]

Always RAW, MDO.

A JPG - even from a phone - has been captured first, then a conversion done.

[biz-engineer]

If I understood (finally) correctly, JPEG was designed to web display. All my photo archives at JPEG... big mistake, I should have increase my storage capacity and archive RAW files, because RAW give latitude to adjust to future display / color gamut. Once converted to JPEG e.g sRGB the wider gamut is lost.

[Dartmoor Dave]

It's a shame that there aren't enough Pentax users around for much of a firmware hacking community to develop. I've got a little Canon A1200 compact that could originally only capture jpegs, but I now use the CHDK firmware hack to shoot raw. It's a bit slow because there's not much of a buffer to work with, but the quality is significantly better than straight jpeg.

Pentax firmware hackers seem to have been mostly interested in DSLRs rather than things like adding a raw option to the jpeg-only compacts.

[MD Optofonik]

If these early JPG only cameras were already capturing the RAW data then what was the reason for not providing access to that RAW data? It seems that providing access to the RAW data became a "premium" feature over the years but the data was already there to begin with.

[Adam]

If these early JPG only cameras were already capturing the RAW data then what was the reason for not providing access to that RAW data? It seems that providing access to the RAW data became a "premium" feature over the years but the data was already there to begin with.

I'd say it's because the users would have no idea what to do with such a file- all they want is a picture Also, without supporting software, it would be useless.

[MrB1]

It's possibly due to -

1. the file size - a raw file can be about 2.5x the size of a JPEG, and memory cards used to be relatively much more expensive.

2. processing speed/time - the processor and memory card in older cameras would have been relatively slow, so the total time for each capture would have been noticeably longer. (The raw data would still have been processed in the camera to produce the JPEG for viewing on the rear screen, but then saving ALL that data to the memory card would have taken more time, compared with saving just the relatively small JPEG file.)

Philip

[Dartmoor Dave]

I think MrB1 is correct on both counts, but particularly the processor and card writing speed. Shooting raw with CHDK on my A1200 means about a 2 second delay between shots while the file gets written to the card, so of course I can only use raw when I'm okay with that lag. The fact that raw is more commonly available as an option with compacts and phones nowadays is probably because they can write the files without too much lag.

[biz-engineer]

Shooting raw with CHDK on my A1200 means about a 2 second delay between shots while the file gets written to the card, so of course I can only use raw when I'm okay with that lag.

Lag is a matter of software implementation, SD card writing could be back-grounded given that there is a cache memory reserved for immediate viewing of current shots. On the K1, once the buffer is full the camera is unusable, but it could be different, it could be possible to still have access to UI event when SD card is being written, simply by multi-threading of the firmware.

[Dartmoor Dave]

Lag is a matter of software implementation, SD card writing could be back-grounded given that there is a cache memory reserved for immediate viewing of current shots. On the K1, once the buffer is full the camera is unusable, but it could be different, it could be possible to still have access to UI event when SD card is being written, simply by multi-threading of the firmware.

I'm going to take your word for that one because it's waaay outside my skill set.

If it's of any use or interest to anyone, here's a comparison between the same shot as a straight-from-the-camera jpeg from the A1200 versus a very quick raw edit. It's not much of a photo, but I think it does show how much of the dynamic range is thrown away by the in-camera processing. You can also see the difference between the same file processed with and without the in-camera lens correction. The colours in the raw are more accurate too -- the soil here really is that red.

In-camera jpeg:



Raw using CHDK:



If only there was something like CHDK for Pentax compacts.

[biz-engineer]

You can also see the difference between the same file processed with and without the in-camera lens correction

Yes, that's a good example. Here the difference between ooc jpeg and post-processed raw is appreciable.

[pschlute]

If I understood (finally) correctly, JPEG was designed to web display. All my photo archives at JPEG... big mistake, I should have increase my storage capacity and archive RAW files, because RAW give latitude to adjust to future display / color gamut. Once converted to JPEG e.g sRGB the wider gamut is lost.

I save my raw files and any intermediate TIFF files if I have used one for editing, in addition to jpeg files. Being able to go back to the original raw file and try out a new processing feature on it is very useful.

ps. it is possible to have a jpeg file with a wide gamut colour space eg. AdobeRGB. The colour space and the file format are two separate things.

[biz-engineer]

I save my raw files and any intermediate TIFF files

Interesting thing, even when exporting dng to tiff 16bits, I could never recover shadow as well as with dng. So I guess with TIFF the dynamic range is lost. I noticed however no banding with TIFF 16bits as opposed to 8bits JPEG.

[RGlasel]

actually capturing RAW images and internally processing them before output?

RAW is the general term for the "native" file format of a digital camera, JPEG is a set of standardized algorithms for compressing visual data and the sensor component in a digital camera has to process the data read off the sensor in order to output a file in any format, RAW or otherwise. Conversion between file formats can be done in the camera or after downloading image files from the camera, but any data not stored in the "native" file format can't be included in another format. Converting a RAW file to a JPEG file will almost always contain less data because most of the compression algorithms combine neighboring pixels into a single value and if the compressed file is expanded again, differences between neighboring pixels in the original file are lost. In order to quickly move data from the sensor to the camera's other processors and the camera's memory, minimal processing is applied to the RAW file, but without some processing, the analog signals produced by the sensor itself are meaningless.

Without JPEG algorithms, the Internet would probably still look like text-based bulletin boards and digital cameras would never have been marketed to consumers. The problem is that once an image file is converted to a JPEG format, so much information is lost that any subsequent processing is going to contain visible artifacts that can spoil the image. DNG files are standardized containers for the image data and metadata supplied by the camera, so that processing software can use the same code for files from different cameras, but it is the embedded programming of the camera that determines what data is saved in the original image file, regardless of the output file format.

RAW is just another example of doublespeak, it creates an illusion of complete control for the camera user, but the reality is not so clear.

[goatsNdonkey]

So far, my attempts to understand, or more often appreciate, the raw processing programs I have looked at have been fruitless, so I shoot in-camera JPEGs with the settings centered (except with my K-R in which I have tweaked the settings slighly to get results that resemble what comes out of my K10D).

My post processing technique is to first export the OOC JPEGs to nice big fat TIFF files using GIMP, and then I use the very simple tools in Shotwell, to (if needed) crop or straighten images, or to make other adjustments in them as necessary. The adjustments it allows, mainly with simple sliders, are exactly the kind of things I would have been interested in doing in a darkroom, adjust exposure level and tweak highlight and shadow brightness. Depending on how I adjust exposure, I can increase contrast. There is a Saturation slider, which 90% of the time I only use to make B&W conversions, by sliding it to zero. There is no sharpness slider. There are color temp. and tint sliders, I hardly ever use, and, when I do, it is mainly to compensate for some color issue in scans from expired film, not in my dslr shots. When I'm done, after saving the adjusted TIFF files with new names, I use GIMP again to export them back to JPEG files (at the highest quality level).

If someone is using a camera that only shoots JPEGs, there are ways to do some good post processing. You can try something like what I do, to make lossless improvements, or I hear that some of the RAW processing programs also will work with JPEGs, not only RAW files, but others can speak to that.

[Note that I am not in the least interested in anybody trying to convince me that I should be shooting RAW. I have not written off RAW shooting completely. Every 12-18 months or so, I re-examine a RAW processing program, and look for the prioritization of features I would like to see such a program have...and when I don't find that, I set aside the issue for another increment of time. I know someone is tempted to argue with me....no, no, no, stop yourself, don't do it, it won't be worth it, save your breath, because I'm just starting another such increment and I won't even hear you.]