Photo Forum / Digital Photography / DSLR Cameras / July 2005
The virtual of RAW
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l e o - 20 Jul 2005 04:43 GMT People ask why use RAW format. I use it often for EC compensation and color balance. Here is another reason. I always complains that many photos I take in the day time with the sky way overblown and asked about advice for a gradual filter.
http://www.fredmiranda.com/article_2/
I found out the article above and picked one of my photos as an experiment. Using normal exposure curve, the photo looks good except the clouds which are just a big white overblown mass. I used linear exposure curve and underexposed 1.5 and recovered the details of the clouds.
I don't even need to take two pictures using a tripod. Hallelujah ...
l e o - 20 Jul 2005 04:45 GMT > People ask why use RAW format. I use it often for EC compensation and > color balance. Here is another reason. I always complains that many [quoted text clipped - 9 lines] > > I don't even need to take two pictures using a tripod. Hallelujah ... BTW, the camera is a 20D. I think doug should try to do some tests with his favorite Panasonic FZ20.
John_B - 20 Jul 2005 18:17 GMT leo, You also could learn how to take the photo correctly in the first place, then you don't need raw.
But good for you, you can correct your mistakes.
"l e o" <someone@somewhere.net> wrote in message news:1MjDe.990$0C.882@newsread3.news.pas .earthlink.net...
> People ask why use RAW format. I use it often for EC compensation and > color balance. Here is another reason. I always complains that many [quoted text clipped - 9 lines] > > I don't even need to take two pictures using a tripod. Hallelujah ... Owamanga - 20 Jul 2005 18:44 GMT >leo, >You also could learn how to take the photo correctly in the first place, then >you don't need raw. Rubbish. Are you seriously claiming that your color-balance is spot-on for every shot you take. Think first: There are 50,000 different color temperature settings, and 300 different tint adjustments - the combination of which gives 15 million different possibilities of which your dSLR may offer around 6 different ones to choose from for any given situation.
>But good for you, you can correct your mistakes. Twaddle. The vast majority of RAW adjustments are not done to fix mistakes.
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John_B - 20 Jul 2005 22:14 GMT Owamanga you ever shoot with film? Did you change your rolls every time for diffrent light levels?
> >leo, > >You also could learn how to take the photo correctly in the first place, then [quoted text clipped - 15 lines] > Owamanga! > http://www.pbase.com/owamanga l e o - 20 Jul 2005 23:39 GMT > Owamanga you ever shoot with film? > Did you change your rolls every time for diffrent light > levels? You didn't get it, so you should just use a film camera.
Owamanga - 21 Jul 2005 00:12 GMT >Owamanga you ever shoot with film? Of course, I started with film, then moved to slide, since I've had the D70 (>6mo) I've taken 1 MF photo with a hasselblad and the rest is pure digital baby!
>Did you change your rolls every time for diffrent light >levels? You can't, it's impractical (unless you are doing commercial work, maybe). Just like you still can't really do it with any significant level of control on a dSLR today. People used to put up with yellow tungsten photos, blue people standing in the shade and even took great glee in cross-processing the negs to widen the gap between the result and reality even further.
Not me, not now. I check and adjust color balance to taste on every photo that's destined to become a print. The only way I could do this before was to scan the negative/slide and work on the RAW file it gave me.
But color temperature controls are just two of the 21 sliders on the RAW importer dialog. Here are some other major ones:
Exposure. This usually needs a tweak. Often less than 1/3 stop which is beyond my ability to control the camera at shoot time, but sometimes more - especially if only one channel is close to clipping.
Anti-vignetting is nearly always employed to provide an evenly lit image, esp. if you are shooting at a zoom's wider side. This helps later with any off-center cropping you might do, preventing a dark corner that you'd get if you didn't do this correction. Minor, subtle yes but I know it's there.
Occasionally you want to increase the vignetting due to it's compositional enhancement qualities. This slider does a much better job than I've seen Photoshop do. Keeps it subtle.
Sharpening. I detest that happening in-camera as it does with a JPEG. This should *always* be the final thing that happens to an image, not the first. Sharpening has to be applied with output size in mind, and no camera allows you to tell it that the destination print is 8x10 vs 6x4 vs a 600x400dpi email so it can modify the JPEG sharpening accordingly.
De-noise filters. Applied automatically when you save as a JPEG, but in reality the quantity of this effect you need changes with each image and the ISO you shot it at.
Shadows. The JPEG gets a 'levels' cut at around 5%, anything below rapidly being pushed to black. This helps cut down shadow noise and gives the image some punch, but often this default is not suitable, especially in high dynamic-range scenes.
Saturation. Again, each image is different. Portraits need less than a landscape of Cinderella's Castle, Magic Kingdom. How can the camera know what you are looking at? It doesn't.
On very rare occasions some of the other sliders get a twiddle: Chromatic Aberration for example.
RAW isn't for everyone, just like doing your own film darkroom work isn't for everyone, but to assume people do either just to fix mistakes is way off the mark.
I believe that the vast majority who use RAW do so to maintain control of the whole workflow, and not just let the camera make up some bullshit defaults and be happy with that. The quality argument is a secondary issue for me, I'm not anti-JPEG, just pro-RAW.
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JPS@no.komm - 21 Jul 2005 00:58 GMT >I'm not anti-JPEG, just pro-RAW. JPEG is a dandy display medium; just not the optimal processing source.
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<>>< ><<> ><<> <>>< ><<> <>>< <>>< ><<> John P Sheehy <JPS@no.komm>
><<> <>>< <>>< ><<> <>>< ><<> ><<> <>>< Darrell - 21 Jul 2005 01:15 GMT >>Owamanga you ever shoot with film? > [quoted text clipped - 11 lines] > glee in cross-processing the negs to widen the gap between the result > and reality even further. In my professional shooting days with film we would use a colour temperture meter, and filter to balance the chromes. With negative film we could correct a fair bit in printing. At a wedding we could swap of a Blad back with VPS to VPL and shoot the candle lit shots, sometimes we could cheat with gelled heads, or later I would just do a soft fill with the modelling light on our Lumedyne heads. I would only correct those about half way, as warm is ok in what appeared to be candle light. I now shoot without a bag of filters, in RAW but I treat the dSLR like a film camera loaded with chrome, as the dynamic range of my dSLR is similar to slide film. The photo still has to be correctly exposed! I prefer the 12 bit RAW over the 8 bit TIFF/JPG, it gives my more control to my output. This is the same reason we printed colour in-house, you will find a truly gifted custom printer in commercial labs. But they often move on, and you have to train somebody else. It's easier to have in studio colour lab, not cheaper! Now with digital the work flow is different, there is post shooting production work, that when people sent stuff to a lab was transparent. If you did your own lab work it wasn't transparent. An average wedding coverage for a 50 shot 11x11" album was 8-12 hours shooting, and 80+ person hours in printing, retouching and prep work to ship the prints down to NYC for binding. So digital to me is a labour saving method, I can't undo a darkroom mistake, like roller marks, cinched prints etc. I can back-up in Photoshop.
JPS@no.komm - 21 Jul 2005 01:26 GMT >I now shoot without a bag of >filters, in RAW but I treat the dSLR like a film camera loaded with chrome, >as the dynamic range of my dSLR is similar to slide film. You get a bit more full-color dynamic range if you use the sensor array's native color balance; magenta filters over the lens (for daylight), or over the flash. Also, unlike slides, you can apply curves to the processed image to bring out deeper shadows, albeit noisily.
Personally, I thing DSLRs at ISO 100 or 200 have a bit more dynamic range than slide film. And the limit that is there, at these lowest ISOs, is the 12-bit digitization, not the sensors. The sensors pick up a lot more usable tones than can be expressed with the 4096 RAW numbers at the lowest ISO.
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<>>< ><<> ><<> <>>< ><<> <>>< <>>< ><<> John P Sheehy <JPS@no.komm>
><<> <>>< <>>< ><<> <>>< ><<> ><<> <>>< JPS@no.komm - 21 Jul 2005 00:29 GMT >You also could learn how to take the >photo correctly in the first place, then >you don't need raw. No matter how many uninformed people make this statement, it is still incorrect. RAW is like "better film". Are you against better film?
Real photographers only use low-latitude slide film?
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<>>< ><<> ><<> <>>< ><<> <>>< <>>< ><<> John P Sheehy <JPS@no.komm>
><<> <>>< <>>< ><<> <>>< ><<> ><<> <>>< John_B - 21 Jul 2005 00:55 GMT Well some photographers can get there equipment to work the way they want, and not need editing like RAW to correct there errors. Some don't.
Raw is not like better film, infact print a correct photo in raw (if you have the talent and software to do so) and print the same correct photo in jpeg and you can't tell the diffrence.
Raw vs. jpeg is more like negative film vs. slide film With negative film there is more room to correct errors. With slide film you get what you took.
I don't need Raw, do you?
> >You also could learn how to take the > >photo correctly in the first place, then [quoted text clipped - 9 lines] > John P Sheehy <JPS@no.komm> > ><<> <>>< <>>< ><<> <>>< ><<> ><<> <>>< JPS@no.komm - 21 Jul 2005 01:13 GMT >Well some photographers can get there equipment to work the >way they want, and not need editing like RAW to correct >there errors. Some don't. RAW is the original digitization of the sensor voltages. In-camera JPEG makes an arbitrary re-mapping of these values, and then smashes them a little flat with lossy compression. Even without the lossy compression, the JPEG set to normal parameters in daylight white balance throws away almost 2 stops of red highlights, a stop and a half of blue, and about a stop of green, on my 2 Canon DSLRs. Not only that, but several RAW levels in the highlight ranges that aren't clipped are posterized to a single level in the JPEG, meaning that you have less capability to enhance areas of low contrast to make them look the way your eyes and brain see them.
>Raw is not like better film, infact print a correct photo in >raw (if you have the talent and software to do so) and print >the same correct photo in jpeg and you can't tell the >diffrence. That is circular reasoning. Let me break your circle; you can't capture the dynamic range in JPEG that you can in RAW. If you limit the DR to what the JPEG can do in your test, of course there won't be much difference.
>Raw vs. jpeg is more like negative film vs. slide film >With negative film there is more room to correct errors. >With slide film you get what you took.
>I don't need Raw, do you? If I want my images to have the kind of DR that I can see detail in with my eyes and brain; RAW takes me a lot closer to that than JPEG does.
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<>>< ><<> ><<> <>>< ><<> <>>< <>>< ><<> John P Sheehy <JPS@no.komm>
><<> <>>< <>>< ><<> <>>< ><<> ><<> <>>< Darrell - 21 Jul 2005 01:33 GMT > Well some photographers can get there equipment to work the > way they want, and not need editing like RAW to correct > their errors. Some don't. RAW is not editing, RAW is the pure sensor data in full 12 bit (14 bit on some equipment) with TIFF and JPEG the camera algorithms decides to throw away 4 bits of info. There is more available dynamic range in RAW, it also is not lossy like a jpeg file. Sometimes a lossy jpeg is good enough.
> Raw is not like better film, infact print a correct photo in > raw (if you have the talent and software to do so) and print > the same correct photo in jpeg and you can't tell the > diffrence. RAW is like better film, it's like shooting Kodak MAX versus a Pro film like Porta.
> Raw vs. jpeg is more like negative film vs. slide film > With negative film there is more room to correct errors. > With slide film you get what you took. Ok analogy, jpeg is like negative film because you settle for what the lab tells you is a good print. RAW is like going into a colour lab and printing my own prints hmmm I did that for 30 years ;) However jpeg uses a lossy compression algorithm, and quality is lost ever time you open and resave the image.
> I don't need Raw, do you? But the discussion can be summed up as RAW is too hard, so I need outside help. I agree 100% with you on correct exposure is key to good images, film or digital. There are lazy shooters that will shoot RAW with the hope that they can use the Photoshop "make it perfect" plug-in. I shoot RAW for all my serious shooting, but might shoot jpeg for a quick web shot or happy snap.
Darrell Larose Ottawa, Canada
JPS@no.komm - 21 Jul 2005 02:02 GMT >RAW is not editing, RAW is the pure sensor data in full 12 bit (14 bit on >some equipment) with TIFF and JPEG the camera algorithms decides to throw >away 4 bits of info. That's not the most accurate description of what is going on. An 8-bit TIFF's 0 - 255 might map from the 100 - 2200 of the 12-bit (0 - 4095) RAW data in the green channel, 100 -- 1600 in the blue, and 100 - 1200 in the red channel, for a greyscale subject in daylight. In the lower parts of the ranges, the TIFF is actually more precise, and in the higher part of the ranges, the RAW is more precise, because the TIFF's values are the base of an exponent raised to the 2.2 power, typically, representing the RAW values, which are linear. Of course, the shadow data comes from the less precise 12-bit linear shadows, so converting them to 8-bit gamma-adjusted values does not realize their precision potential. however, demosaicing creates more values than are present in the 3 separate channels combined, so the precision is sort of used, anyway.
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<>>< ><<> ><<> <>>< ><<> <>>< <>>< ><<> John P Sheehy <JPS@no.komm>
><<> <>>< <>>< ><<> <>>< ><<> ><<> <>>< Randall Ainsworth - 21 Jul 2005 05:33 GMT > leo, > You also could learn how to take the > photo correctly in the first place, then > you don't need raw. Another twit suffering from DKS (Don't Know sh.t).
John_B - 21 Jul 2005 11:50 GMT Randall Assworth, Thank you for your useless opinion but like usual you are wrong!
> > leo, > > You also could learn how to take the > > photo correctly in the first place, then > > you don't need raw. > > Another twit suffering from DKS (Don't Know sh.t). Randall Ainsworth - 21 Jul 2005 13:24 GMT > Randall Assworth, > Thank you for your useless opinion > but like usual you are wrong! Clever...never heard that one before.
The post I replied to said that people who used RAW didn't know how to take pictures. That moronic statement shows that the person doesn't know what they're talking about.
I shoot RAW about 99.999% of the time because it gives me more control over the final image. I don't mess with white balance (and shouldn't have to) and I've been very pleased with the prints I've had made.
I've been doing photography since 1966 and made a living at it for 16+ years. Anything else you'd like to know?
John_B - 21 Jul 2005 14:38 GMT Well I am glad you didn't get hurt by my reply. Actually I was just going to post an apology, why? Because two wrongs don't make a right.
I also have been doing photography for over 20 years 14 proffesional
I have also been a Graphic Designer for Corporate layouts and ads for just over 10 years.
I don't shoot raw (don't need to), and my photos are good enough for me and my clients [just like slides].
But isn't that the real beauty of Digital? Being able to choose the way you want to do it! Thats what attracted me to DSLR, prior to that digital was a joke :+)
> > Randall Assworth, > > Thank you for your useless opinion [quoted text clipped - 12 lines] > I've been doing photography since 1966 and made a living at it for 16+ > years. Anything else you'd like to know? Bill Lloyd - 26 Jul 2005 02:43 GMT > leo, > You also could learn how to take the > photo correctly in the first place, then > you don't need raw. Ummm... NO.
For situations with high dynamic range, you can't "take" the photo without help.
Sure, you can use an ND grad filter to take it "properly" in the first place, but an ND grad is typically a straight line, and getting it "perfect" where the horizon isn't completely straight is going to leave evidence. In the linked picture, the rock in the foreground would have a dark top... so you coldn't GET this same exposure, period.
> But good for you, you can correct your > mistakes. Well it makes adjusting white balance and a number of other things in post processing significantly easier, yes.
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