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william_frucht

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  1. Correct, Andrew, but I never said ISO is an attribute of exposure. I said that correct exposure happens in the camera and that ISO is one of a camera's basic controls. (If you're shooting film, it's an attribute of the film you've chosen.) A beginning photographer needs to understand how aperture, shutter speed, and ISO interact--along with many other things, but those are good ones to start with. What your comparisons have succeeded in demonstrating is the truth of the OP's original complaint: when he tries to brighten his images in post, because they're underexposed, he gets added noise. He wants to know what to do about it. My solution is that he needs to expose his images properly in the first place, because the farther he drifts from correct exposure, the harder it is to get a usable photograph out of what he's shot. Your solution is--well, frankly, I don't know what your solution is. Perhaps it would be helpful if you would stop arguing with everyone else and tell the OP what you think he should do. (The pronoun is another assumption. Apologies, KoolM1, if I've gotten that wrong.) As for your comment that it's overexposing the highlights that causes blown-out highlights, not adjusting your settings so that shadow detail is properly exposed, as far as I can tell this is a distinction without a difference. Most people--certainly most beginning photographers--are not going to spend time worrying about their sensors' response curves while they're out shooting. Maybe, as on my X-Pro 2, they'll darken or lighten the image by a stop or three, but that's the extent of it. Most photographers in the field will stick to the camera's basic controls, as they should, and concentrate on the important things: composition, mood, color, framing and other elements of making a good image.. If faced with a difficult lighting situation, they'll bracket their exposures--another thing KoolM1 should be doing. Anyway, reply however you want. I'm done with you. Which is not to say I won't respond to other posts. Just not to yours.
  2. Ed, I agree, and as I noted, exposing for the shadows with a digital camera can give you blown-out highlights. It's also true that good cameras today, which claim 14 stops of dynamic range, capture a lot of shadow detail that older cameras may not. I still think Adams's advice is worth heeding: get the information onto the sensor--even if, as you point out, we now have to worry more about the other end of the histogram. Point taken, and truth be told, I'm still working mostly with film.
  3. KoolM1, your original question seems to be what to do if your images are underexposed. And I'm guessing from the lack of detail you've provided that you're something of a beginner at this. Let me answer you from the viewpoint of someone who's closer to a beginner level than Andrew Rodney's level. First, correct exposure happens in the camera. You need to know how your camera's basic controls work: aperture, shutter speed, ISO. You may want to take your camera off automatic mode and shoot manually until you have a sense of how these functions interact, and how they relate to movement and depth of field. You may want to invest in a good tripod--make sure it's both light enough to carry around and sturdy enough to support whatever camera you're using. Back when everyone who wanted to learn photography seriously passed through a stage of shooting Kodak Tri-X 400 with a fully manual camera (because that's all there was) and developing it themselves, we were told "expose for the shadows, develop for the highlights." This is still good advice if you're shooting b/w film, but with many digital cameras it can lead to blown-out highlights--less so than it used to, though, as cameras' dynamic range improves. There are ways to bracket exposures and merge them; I won't get into that here. In brief, you can do a lot with a properly exposed image. With a poorly exposed image, you can do much less, and you may never get it to look good. Your post-processing software offers you a lot of different controls, many of which can help if used gently. Raising the "exposure" (whatever that actually does) can help some. Bumping up the brightness of the shadows may help some. There's a noise control function that you'll want to use, because any brightening of an image can increase the noise level. Again, "gently" is key: a little bit of adjustment goes a long way, and unless you know what you're doing, if you find yourself making large adjustments you may be making things worse rather than better. The poster who suggested you use curves was offering good advice: at a certain point, you may find yourself doing almost all your tonal adjustments in curves, because it's the most precise way to control tonality. In Photoshop, which I use along with Camera Raw, you can make all of these adjustments on selected parts of the image, so that different areas have not only different brightness but different contrast levels that you can set just for that part of the image. But note that Ansel Adams's advice from a half-century ago still applies: "Get the information onto the negative." If there's no information in your shadows, no amount of brightening will put it there. All you'll get is more noise. So, to update Adams, get the information onto your sensor. If it's there, you can work with it in any number of ways. If it's not there, you may need to throw away the image and work on a different one.
  4. <p>Jake, I often do the same thing--scan b/w film as if it were color--but I generally don't worry about the color cast that comes out of the scan. Much more important is that the histogram be reasonably balanced. If your histogram is pushed way over to the right, it means you're losing information. Instead of 256 gradations from pure black to pure white, you may have only 150 or fewer gradations that you can actually use. When you correct the exposure in Photoshop (which, by the way, you're probably better off doing in Camera Raw, before you even get to Photoshop), if the histogram looks jagged with lots of gaps, it means you've lost information. The image may look OK, but you may have trouble recovering shadow or highlight detail, and your midtones may not be as smooth as you'd like. (In your excellent flickr images, for instance, I'd be unhappy with the tones in that very pretty girl's blouse.) I have Vuescan but don't use it much--I prefer Silverfast--but both programs give you an option to select your film type and correct the exposure in the scan. The only thing I really care about in a b/w scan is that the tones be a balanced representation of what I was trying to photograph. Ansel Adams's advice--"Get the information onto the negative"--applies here as well: get the information into the scan. The more information you preserve from the negative, the more flexibility you have in post-processing.<br> As for the color cast in the scan, I pretty much ignore it because there are so many ways to fix it later. If you open the image in Camera Raw before starting to work on it in Photoshop, a bad way to correct the cast is to pull the saturation all the way down or select "convert to grayscale" in the HSL/Grayscale menu. I do something that's probably just as bad: when I first open the image in Photoshop, I select "Image/Mode" and click on "grayscale," let it convert, and then change it back to "RGB color." This gives me an image that is a perfect neutral grey, but with RGB channels that will allow me to open it in Silver Efex Pro. After that, I don't even think about toning the image until I get to the print dialogue--although, of course, there are plenty of ways to tone it before that point.<br> Scanning color is a whole other ball game: There you really do need to worry about the color you're capturing in the scan. </p>
  5. <p>John-Paul, I have the same setup--Opticscan 120 run from Silverfast--and I tend to be very intuitive about the settings. Keep playing with them until the image looks good. Ansel Adams's advice still holds: "get the information onto the negative," or in this case, into the scan. I actually prefer a somewhat overexposed, low-contrast scan because it's easier to darken it later than to brighten it, as brightening can introduce noise in the shadows. I agree with Charles that you should make sure you've selected the correct film type. But if you have, and the scans are still overexposed, you can use the sliders to lower the exposure or adjust the histogram until it looks better. Remember, too, that once you start working with the image, you can always lower the exposure in Camera Raw before you put it into Lightroom or Photoshop--where you can also darken it. <br> The detail that concerns me more than the brightness is that you have the resolution at just 300 ppi. Unless you have a severe problem with storage space on your hard drive, the resolution should be up around 2650 or even 5,300. (There's also an option for 10,800 but that's only for fanatics.) Otherwise, if you need to crop or make a large print, the image will look soft. </p>
  6. <p>I bought the OpticFilm 120 about a year ago to use with my iMac and always had problems with the Silverfast software. The biggest problem was that often the scanner wouldn't run at all, even though the software was clearly detecting it. After about half an hour of restarting over and over it would finally run. At the suggestion of a Plustek tech support person I detached everything else--my pen tablet, my backup hard drive, my printer--and this got me down to about 10 tries before the thing would fire up. It was like starting an old car on a winter morning. Then software functions gradually began disappearing: the histogram wouldn't show up, the grain reduction wouldn't show up. Sometimes all the functions were greyed out and the scans came out blank. Eventually, after about six months, the software just stopped working. Uninstalling and reinstalling didn't help. So I got Vuescan, which works fine. A little hard to use, but I follow what Ansel Adams said about exposing film: "Just get the information onto the negative." Just get the information into the scan and you can always adjust it into a good print. </p>
  7. <p>Adrian, bending of film in the scanner is much more of a problem with MF than with 35mm, and if some areas of your images are sharp but others are soft, this could be what's happening. Even a barely detectable warping will throw parts of the image out of focus. When I had my late, lamented Nikon 9000, I had to use a glass negative holder. Let me suggest a simple test that will tell you if the problem is in the camera or in the scans. When you magnify your images in Photoshop (or Lightroom, Aperture or whatever), look for the grain structure. In the sharp areas, of course, both the image and the grain will be sharp. In the soft areas, if the grain is still sharp then the problem is in the camera. If the grain is soft (or not visible), the problem is in the scans: the negative is not being held flat enough. I'm currently using a Plustek Opticscan 120, which has other issues, but the negative holder is quite good.</p>
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