On 2/8/03 7:54 pm, "Shangara Singh" wrote: > One big advantage in shooting in RAW format is you can set the color > temperature at a later date if you have been shooting in changing light > (yes, I know you know that).
I do know that, yes :-) However a question back at you. How do I set the colour temperature? Not how, as in the software side, but how as in, the value? If I have no reference point, such as a grey card in the shot, how do I know where the white balance point should be? I've tried this previously on a shot, and found the guesswork to be impossible. Maybe I've missed some trick of how its done? (I think I was trying it in the Canon software, which we all know is sh*t, so perhaps its easier using other software. In the Canon version I seem to remember you simply had to guess at a fixed Kelvin value, not much use really) Also, remember that we don't all shoot in changing light conditions! My work by nature, is staged, and the conditions controllable to some extent. > If shooting in a studio with set lights, this may not be such a big advantage. Its of no advantage in a studio. And very little, IMHO on location, for the type of photography I do. On location a shot is set up, and a few hundred frames taken. At the start of the shot, I'd either select, Auto-White, Daylight, (Shade, unlikely) or put a grey card in the shot and use a custom balance. Chances are the custom would be the worst, as I probably wanted that sunset light, that its just removed :-) Plus, is it really that hard to change the colour of the shot afterwards? I know its not easy, but surely using Photoshop or PRP a little tweaking could be done? Like I say, its not usually a problem for the work I shoot. > The exposure can be pushed a little further and colors tweaked in > 16-bit/Channel mode so that the file doesn't fall apart as quickly as the JPEG > does. Again, perhaps its due to the nature of my work. My exposure is usually pretty much spot on (its focus, that usually gets me :-) My camera has a histogram function and a preview LCD, so I shoot a few frames and check these things before doing the actual shot. Obviously this will be different for other types of photography, where shots are not set-up. > Also, it's almost certain that the RAW processors will improve over time > so you hedge your bets by outputting as RAW for future iterations of the file. As most of my work is for either editorial use, or maximum A3 print for my own satisfaction. The improvements that might be made in the future do not interest me that much. (they interest me, but not regarding how I might re-print my work). My 10d and my current software already perform more than capably enough for my own personal needs. snip Quote: I rotate in Graphic Converter as it is lossless (Paul T) > Is this an old wives tale? <G> Lossless rotation? I think not. Its been discussed on many a forum. > Save a JPEG from a RAW or take a camera originated high quality JPEG. Dupe it. > Rotate one in GC or iView (I have iView and not GC). Rotate the other in > Photoshop (save it at 100% quality if you want to and close it and then open > it again). Put the two on top of each other and change the blend mode to > Difference. There may be the odd pixel value changed but if you can see a > *marked* difference at 100%, or even 400%, I'd be very surprised. It certainly > is not going to print. GC does the job 100% lossless. It also does the job, by previewing only thumbnails of all the images, then allowing me to rotate them all at once. Its not quick, but its not bad and doesn't require any other interaction. If I were to open up 100 frames per shot in PS, then rotate them and re-save them in PS, for one it would take longer (I imagine, I'm not going to be the one running the test :-) but also it would require more steps of interaction and require a re-save as a JPG, something that I would not recommend to anyone on the planet, as I made clear to the original poster :-) > If you are outputting your files as JPEGs from your camera and you accept > that quality You make "accept that quality" sound as if the results of a JPG from a camera are somehow immensely inferior to a RAW output. I would still debate this. As my understanding of JPG compression goes, its pretty clever stuff. If you take an original RAW/TIFF whatever and only ever save it once as a JPG, the process will throw away some information. However the type of information it throws away is stuff that you would never have known was there in the first place and more to the point will never miss, the image will show no degradation. Re-saving the file as a JPG, WILL, as far as I've been led to understand, start to show some degradation. Whether this is acceptable or not is up to the individual. > the change is so minimal as to be negligible. So, I wouldn't > go as far as to say Photoshop will "degrade" your image when it rotates a > JPEG. It does change the value of some pixels but certainly not degrade the > image when judged visually. In fact, if you compare a losslessly rotated > JPEG and the RAW it came from, you will see a similar difference. On one hand you are saying it will degrade my image, on the other hand you are saying that I shouldn't worry about that degradation because I won't notice it anyway? Think about this, and refer it back to why its OK to shoot JPG instead of RAW, if that's what you need to shoot. Once you have your JPG from your camera, regardless of what minor image degradation may follow from repeated JPG savings, what is the need? Why would you want to resave as a JPG, when there are other choices available to you? The whole point about shooting JPG from the camera is a whole different issue to saving JPG's on a computer, they cannot possibly be compared, or more to the point, should not be compared. >> Think of it this way. A jpg file produced by your camera is your "negative" >> once it leaves the camera and arrives on your computer, do not touch it ever >> again. > Well, it's not a negative in the traditional sense of the word. Hence the phrase "Think of it this way" indicating that it isn't actually a negative, but pays to think of it that way, since it is the "original" that came from the camera. If the guy still had the RAW file, that would be his theoretical negative. He doesn't have that, so by default the original JPG becomes "the negative". Not a film negative, it doesn't have an emulsion, but the closest thing to a negative in the way most photographers think about the digital process. And most people appreciate the use of the term so that they can relate their existing knowledge, the world of digital. I think you'll find that it helped Stephen understand, it certainly helps most people. > It's already been processed by your camera once. The RAW file format comes > closest to fitting the description of a digital negative. As explained above. There is no such thing as a negative in digital work. The term "negative" is used by most people, to indicate an "original" that other images are produced from, and that these daughter images can be altered in some way without affecting the original "negative". If one reserves the term "negative" exclusively for RAW files, what would you have us call a JPG that comes from a camera, where the RAW file was never saved? Personally I think the term "negative" is more than adequate for the task and easily understood by most users. >> PS - RAW v JPG - as I pointed out on another list recently. RAW is better >> than JPG, it contains more original data. However this does not mean that >> everyone needs to shoot RAW files. In an ideal world they would. But the >> world is not ideal, just yet and JPG files made on the camera and not >> resaved afterwards, will be absolutely fine for most peoples uses. As an >> example, I've shot magazines, A4 full bleed glossy magazines, with JPG files >> and I doubt if there was a single soul in the world, that could have spotted >> the difference, between my JPG's and a RAW file shot at the same time. > > Try the same test with rotating a JPEG. See if anyone can spot the > difference between Photoshop rotated files and software that does "lossless > JPEG rotation." I think you may be pleasantly surprised. As pointed out above. Its not a case of "will the degradation be visible", there is simply no need to re-save as a JPG once the image is on a computer, trying to prove that one can do so with "minimal" loss is irrelevant, who would want to? If I want to rotate in PS, then I'll rotate, then re-save the image as a TIFF/PSD with NO LOSS, like any sensible person would do, wouldn't they? --------------------------------------------------------------------------- Here is a copy of what I originally wrote regarding RAW v JPG (on the epuk list), perhaps it explains it better. I'm not anti-RAW. I'm just not anti-JPG as some people seem to be. I repeat, in an ideal world, we'd all shoot RAW, no-one should disagree with that. But the world is not ideal and some of us are forced by pressures involved with our type of photography, to shoot JPG. Any new user reading this forum (or any other) should not be forced into the impression that some users give, that it is ONLY acceptable to shoot RAW images. There is a time and place for RAW and a time and place for JPG. Both are necessary at this moment in time, (in the future this will no doubt change, but we don't live in the future) To shoot RAW or not (ie shoot JPG instead) This equates very nicely to shooting 10x8 trannie or 35mm, which is better? A few photographers on this list have pointed out that they only shoot RAW (Tony being one of them, hence why I've used his post as an example). Is this the right way to go? Well yes RAW is "better" than JPG. Nobody will disagree with that (unless they are really ill informed on the matter). Same as 10x8 is better than 35mm (I'm sure we'd all agree). However, it all depends on final usage. Just because 10x8 is better quality does not make it suitable for all jobs. Speed - speed of shooting would be one issue, excess quality would be another. If you shoot on one of the current 35mm style digital SLR's, you will find the buffer size very limiting, if shooting RAW files. It can be done, but there will be a lot of waiting in between burst of frames. Obviously this depends greatly on the subject matter. If you have time to wait between frames, by all means shoot RAW. For many fashion jobs, it is impractical. Especially if trying to capture a moving model. Again, this all depends on the style you shoot. For some it will not prove a problem, for others it will. Quality - Do you really need 10x8 quality, for that picture going in tomorrows newspaper? No, you don't. If you take a RAW picture and a JPG side by side (JPG at max quality) then print them both out, will you see a difference? Many commentators have said, no you won't. Try it yourself and see if you can tell the difference, I doubt it. Yes, the RAW file will have more detail in there, but can you actually see it? And when you print it out at magazine size (A4) or newspaper size (fashion ends up about 6 inches tall max) will you be able to see the differences? No you won't. I have produced full bleed A4 magazine pages in Wedding & Home magazine, which is fairly well printed (not the greatest, but it is a full glossy mag) which were shot JPG. Did anyone notice? Do you think there is any photographer or client or any human in the land that could tell? I doubt it. So why shoot RAW at all? Is that what I'm saying? No, I'm not. I'm saying, that there is a time and place for shooting RAW images. In difficult shots, shooting RAW will give you more room to play with in the final image. For making tonal adjustments, exposure adjustments etc. It is the best that the camera can capture, and should be used if possible. However, for the vast majority of work, shooting JPG (at the max setting) is more than enough quality for most peoples needs. And is in no way "unprofessional" or "unacceptable". Do not be scared to shoot JPG. Regards Paul PS - Please remember, that if shooting JPG, immediately save the images as Tiff's/psd's as soon as they are on your computer. Work in those formats for re-saving images, not JPG. Only re-save as a JPG at final output and ONLY if really needed (i.e. A Newspaper - Daily Mail, can't cope with Tiff's, so request JPG's instead) Therefore my workflow for them is - shoot JPG, save as TIFF, work on file, save final output as JPG (max 12) burn to CD. -- Paul Tansley Fashion & Beauty Photography London +44 (0) 7973 669584 http://www.paultansley.com =============================================================== GO TO http://www.prodig.org for ~ GUIDELINES ~ un/SUBSCRIBING ~ ITEMS for SALE
