Why RAW AND JPEG?

[Alis]

Can someone explain why even DSLRs record JPEG and RAW at the same time? What is the use for it if you are going to and can adjust the picture later yourself, why would you want the camera to do it for you and eat more memory space?

Sedali

[shreds]

Sedali,

I generally use JPEG+RAW because sometimes I need a very fast turnround and the Jpeg will suffice without any post production in these cases.

By taking a RAW, firstly I have a backup/insurance and secondly I can select certain images where time is less of a constraint and play around with its settings to produce jpegs from the RAW files.

For me, disc space isn't an issue as I normally run 2x4Gb cards which will generally cover most days (but always carry backup) and by staying at 4Gb I don't put all my eggs in one basket.

Once back at base I store all images on 2 x 400Gb HDD and have a backup 750 Gb backup to hand. The cost of HDDs nowadays is small compared to a few years ago and as far as I am concerned it is still cheaper than buying film.

HTH

[David]

Hi Sedali

In addition to Shreds' point, which is to do with the use of JPEG, DSLR cameras produce JPEG images on the fly - they are what you see on playback on the LCD screen of your camera. So the camera firmware does this conversion anyway. With Canon DSLR's and I assume other makes as well, you have a choice to save just the RAW file or both RAW and JPEG. I tend to save only the RAW image, but in Shreds' case he can make use of JPEGS directly.

I also agree with Shreds about memory. Two or three years ago memory cards had small capacity and were expensive. Nowadays those are no longer issues. So if a photographer wishes to store both on his/her memory card, there is not a problem.

Cheers

David

[atvinnys]

David,

I think there are a couple of differences here but I might be wrong.
whether you shoot JPG only or Raw only or combined, I think there is always an embedded JPG used for thumbnail...this is not a good JPG, and probbaly very small.
the JPG you would shoot while shooting RAW+JPG is way better than that, so it probably requires more processing (not even sure what kind of processing is applied to the thumbnail, and actually makes me wonder what JPG is actually shown on the LCD screen).

As for preview: well, in my case I have a Canon Rebel XT (starts to be old), and I use the faststone viewer which knows about the CR2 files. So no need to actually save an extra JPG.(esepcially since my rebelXT only allows me to save Large JPG while saving raw...not a space saver on CF).

So I guess it's a choice. in general, I would test if the viewer you are using knows about your Raw file and can do a quick demosaicing, in which case, I think you would not need to save both, but just the Raw.

[Dave Humphries]

In my experience, I get the impression that the embedded jpg in the Fuji RAW format is always 1600 x 1200, just over half what my 6M pixel camera is capable of, and it doesn't have a RAW+JPG option.
Of course, Canon may be different, and I may be wrong altogether on this!

[Henry Peach]

If a photographer normally shot jpeg, but wanted to start learning raw processing saving both types of files would offer them the opportunity to practice raw processing, while still having the jpeg back-up in case they needed it. I see a lot of posts on internet photo forums that go something like this "I switched to raw because they said it was better, but my raw photos look lousy compared to my jpegs!"

And on the other hand, people who are comfortable with both may use their jpegs 99% of the time, but like to be able to fall back on the raw file in case they goofed the exposure, wb, etc....

[rpcrowe]

Cameras, especially ones that are not the very latest models often have a smaller buffer and therefore will not be able to shoot as long a burst when doing both Raw and JPEG than if doing RAW alone.

[exposed]

There is one other important factor for the JPEG shooter. The JPEG image that you have on your camera CF card is already on its first stage of degradation.

When the JPEG is saved in your camera it is degraded by compression, a process that samples 16x16 pixel chunks into a compressed JEPG file. You can set the level of compression in your camera, together with the degree of sharpening, contrast, colour balance, etc. These are all saved as the first (degraded) JPEG file on your CF card.

After copying to PC you may wish to modify the image (crop it, colours, tonally, tricks, etc). When you save it you have then reached the 2nd level of degradation. One more slight change and you have reached the 3rd level and your image is beginning to looking blotchy now. Lots of artifacts etc. Not good for showing to friends perhaps. Sad for you maybe as it is easy to save files writing over the original (better quality) image file.

My advice, even if you have no intention to process RAW, or pehaps cannot afford the software and PC to process RAW, is to shoot always BOTH JPEG and RAW. Why....?

Well in my case when I started digital, RAW was not available. So all my imaged got degraded and now cannot be used. I learned the hard way. Later when I upgraded to a better camera I set RAW and JPEG, even though I did not understand or process my raw images ( I just archived them). Now, with a few years of photoshop, reading books, and accumulating knowledge, I find I can really take joy from my former RAW files. The raws represent the original un-degraded image and can be turned into a pristine image with today's techniques. The raw has no sharpening applied, so I can de-noise the image and produce a first class image - even the old raw was from an inferior camera by today's standards.

[crisscross]

with Nikon DSLR its a non-issue - just shoot .nef; free Nikon View NX not only gives preview, but updates it to the latest version edited in Capture NX2 (still .nef) or allows basic editing, printing and/or conversion to jpg or tif all without messing the original .nef. I think the camera also allows internal editing to wire direct to a printer, but would never do that.

[dendrophile]

Something that caused me to put my camera in RAW+JPEG mode was that when I bought my camera (Canon 50d) neither Apple nor Adobe had a RAW convertor, so the only way I could edit my photos in Aperture or CS2 was to use the JPEGs the camera wrote out. Now both Apple and Adobe have raw readers for the 50d I can go back and re-edit my photos using RAW as a starting off point. So, I used the RAW+JPEG as a bit of a rescue remedy. The camera is back in RAW only mode now.

HTH
Dendrophile

[nagoyait]

Also, I think another reason is that somebody will have a Hard drive-based portable photo storage device or portable media player that has a screen. You can just plug in your card and upload your photos for review on a bigger screen then wipe the card for reuse. Historically they couldn't display RAW so you would include the jpg. Now some do display RAW but I doubt it works for newer cameras and waiting for the converters might be a long wait.

Steve

[McQ]

There's also a lot on the topic of whether RAW+JPEG is ever a justifiable option at this thread from several months ago:
Save photos in RAW+JPEG using low/high quality or in sRAW?

[GraceBourke]

I have been shooting Raw and JPEG for more than 2 years. I shoot both because the RAW gives a lot more detail in the image. I was taking a nature photography class and the other student had the same camera, Canon Digital Rebel XT. She shot only large JPEG. She, the teacher, and I all noticed that my pictures in Raw had better resolution and were crisper. I print my photos as greetings cards and enlargements, so I want the maximum resolution and detail possible.

I still shoot with the JPEG because it does some really good light balancing, color corrections, and image enhancing that I am still learning how to do in Photoshop. Also, I use a PC with Windows XP and it won’t do thumbnails of Canon’s Raw CR2 files. So, I need the JPEG to be able to see the thumbnails.

[Colin Southern]

I like to think of JPG -v- RAW as being a bit like purchasing a TV Dinner -v- cooking the ingredients yourself; in the case of the TV dinner you have to trust that whoever prepaired it did so to your liking, whereas of course when you do it yourself, you have total "creative control". If you buy both then you can simply sample the TV dinner, but throw it away and cook your own if it's not to your liking.

Personally, I'd be quite happy if the JPG options were removed from my Canon 1Ds3 altogether (I never use them) (perhaps replaced with a DNG format option?) - however the JPG + RAW option is popular with the likes of wedding photographers because they're dealing with many hundreds of shots and on many occasions the camera's JPEG is of satisfactory quality (especially when you've learned to get consistently good exposures and nail your white balances).

Now days we have tools such as Lightroom that make processing bulk quantities of RAW files as easy as working with JPG, so possibly more may use RAW in future.

Cheers,

Colin - pbase.com/cjsouthern

[rpcrowe]

I totally agree with Sedali.

I have any number of CF cards (4 gigs maximum size) and for an old film photographer like me (especially one who began professional photography using cut film in press cameras) switching a CF card is darned easy and safe.

I shoot JPEG + RAW because I occasionally need the slightly quicker turnaround of the JPEG. I have sometimes downloaded images to a friend's computer and he doesn't have the capability or knowledge base to work in RAW. It also seems like a safety factor to have the images captured in two different formats. This may not be a valid safety insurance but, it provides me with a modicum of peace of mind.

At the few occasions when I need to stretch out my burst capability, it is easy to switch to RAW capture only. I would never shoot in JPEG only.

I don't mind using the extra memory since it has become relatively inexpensive in the past couple of years.