tag:blogger.com,1999:blog-36939759.post2998698141993157095..comments2024-01-17T07:03:57.842+00:00Comments on The Mad Ranter: Digital Camera Guide Part 4FlipChttp://www.blogger.com/profile/09449939046593105926noreply@blogger.comBlogger10125tag:blogger.com,1999:blog-36939759.post-50962520466665518102009-04-20T16:30:00.000+01:002009-04-20T16:30:00.000+01:00I can understand the autofocus not working when it...I can understand the autofocus not working when it's dark. Obviously it needs light to be able to see so it can determine if the image is focused. My problem is <EM>it's not dark!</EM> It's not even <EM>slightly</EM> dark. It's really quite bright. But my camera still can't see anything unless it's <EM>dazzlingly</EM> bright. It just seems absurdly insensitive to light for whatever reason.Orphihttp://blog.orphi.me.uk/noreply@blogger.comtag:blogger.com,1999:blog-36939759.post-29675122901845886162009-04-20T09:45:00.000+01:002009-04-20T09:45:00.000+01:00First off I've added an simple and complex entry f...First off I've added an simple and complex entry for DoF on its own. The simple boils down to big number aperture = big depth of field.<br /><br />As for the LCD screen I agree with Dan, and that's why the focus lock is an important feature. Not only does it allow you reposition the image, but it stops the camera changing any of the settings. So if you focus-lock and it appears dark then that's the shot you'll be taking.<br /><br />Dan - looking at the manual it appears the S304 only has a centre AF point, if Orphi's just taking the shot as is then it would have been pointed straight at the tree. My only thought on this point is that he's not using the focus-lock option to allow the camera a chance to adjust?<br /><br />Orphi - Okay colour cast. I mentioned that there's normally one present at all times yet our marvellous brains can filter it out. So why do we get a blue colour cast on some outdoor shots? Look up at that big blue sky and consider why the sea appears blue. The way to get around it is to use a White Balance function.<br /><br />Unfortunately the S304 doesn't have a manual white balance setting only presets. I guess it's set to Auto, try Daylight (little sun picture), Shade (sun with cloud) or Cool White (centipede with 3). Ah hell try them all and see what they do.FlipChttps://www.blogger.com/profile/09449939046593105926noreply@blogger.comtag:blogger.com,1999:blog-36939759.post-12571367603996991832009-04-18T23:55:00.000+01:002009-04-18T23:55:00.000+01:00"As for the camera's sensitivity, I just note that..."As for the camera's sensitivity, I just note that when you look at the LCD just before taking a shot, the image almost always comes out very dark unless you have intense illumination of whatever you're pointing the camera at. The autofocus also stops working unless you have such illumination."<br /><br />In low light, often the camera will use a slower shutter speed to let more light in, but when it has to operate the sensor continuously to keep the screen updated, it can't vary the shutter speed, so the picture will be darker. That's another advantage of using the viewfinder to compose your shot. The autofocus uses the image the sensor is continuously recording to find the optimum focus, by varying the focus until the contrast of the shot is at its greatest (which indicates that edges are sharper), so again, that's why it doesn't work in low light.<br /><br />The sky in the image you link is pretty decently exposed: the camera doesn't realise that you're trying to expose for the foreground objects, which take up less than half the frame. As I mentioned, setting the autoexposure mode to "AF point" or "centre-weighted" might have given you a better shot in that case.<br /><br />"I doubt owning a more expensive camera is going to solve the problem that I tend to photograph very boring objects..." No, that's something you can only change by practising more, regardless of what camera you have. You have to learn to take shots within the limitations of the equipment. "...or that sometimes it's impossible to stand far back enough to get everything in shot." Well, with an SLR, you have the option of buying a more wide-angle lens, but again, you need to learn to work with what you have.<br /><br />A smaller aperture gives you greater depth-of-field, which means that objects are less blurry. Think like a pinhole camera: an infinitely thin pinhole will give you a perfectly sharp image at all distances, but infinitesimally much light will get in. A big fat pinhole will let more light in, but the picture will be blurry.<br /><br />All cameras overexpose sometimes and underexpose sometimes. Just learn when it is likely to do either of those, and adjust the exposure accordingly. As for taking every shot six times, many cameras will do that for you automatically: it's called exposure bracketing. They take a shot exposed with the selected settings, another slightly overexposed, and another slightly underexposed. (How many, and how many stops of exposure it sets, can usually be set in the camera.)Dan Hhttp://surreal.istic.org/noreply@blogger.comtag:blogger.com,1999:blog-36939759.post-39142915809765412262009-04-18T19:16:00.000+01:002009-04-18T19:16:00.000+01:00I don't think anybody is debating that the pic...I don't think anybody is debating that the pictures in this series are overexposed; that seems fairly obvious. The question is just “why?” Similarly, why the blue tint? I can probably remove it, but why is it there in the first place?<br /><br />As for the camera's sensitivity, I just note that when you look at the LCD just before taking a shot, the image almost always comes out very dark unless you have intense illumination of whatever you're pointing the camera at. The autofocus also stops working unless you have such illumination.<br /><br />(Take a look at <A HREF="http://www.orphi.me.uk/rev1/04-Photos/2004-03-11/23-Ace3.html" REL="nofollow">this image</A> for an example of an image which is, IMHO, under-exposed. Presumably because of the sky? I would have thought it would be possible to do better than this, even with the amount of sky though.)<br /><br />I doubt owning a more expensive camera is going to solve the problem that I tend to photograph very boring objects, or that sometimes it's impossible to stand far back enough to get everything in shot. But I'm sincerely hoping that a better camera won't constantly eat batteries and will work properly in lower lighting conditions. That would be something…<br /><br />FlipC: Maybe you would publish a short summary. For example, I recall that apature and DoF are related, but off the top of my head I can't remember which way round. (I.e., does a small apature give you a large or a small DoF?)Orphihttp://blog.orphi.me.uk/noreply@blogger.comtag:blogger.com,1999:blog-36939759.post-34672831948548024092009-04-18T17:12:00.000+01:002009-04-18T17:12:00.000+01:00Dan I agree all the shots shown are over-exposed, ...Dan I agree all the shots shown are over-exposed, however as Orhpi has said before and just now is that his camera seems to also be prone to underexpose. This suggests the camera just can't grasp how much light is around; this is why I mentioned the EV setting when I was adjusting is photo in my other entry.<br /><br />Orphi - glad you found that setting. From the manual it appears you have a small ability to alter the aperture, the exposure and the white balance. The white balance as I mentioned in um part 3/4? is to deal with exactly the colour cast problem you've been experiencing.<br /><br />As for the book, yeah to an extent this is why I tried to write what I have and keep it as simple as possible.FlipChttps://www.blogger.com/profile/09449939046593105926noreply@blogger.comtag:blogger.com,1999:blog-36939759.post-27912648383766875332009-04-18T14:04:00.000+01:002009-04-18T14:04:00.000+01:00“All the problems are due to overexposure.”
Well,...“All the problems are due to overexposure.”<br /><br />Well, except for the small objects that won't focus. ;-)<br /><br />I find it kind of ironic that the camera refuses to work without copious amounts of light, and yet on this bright, sunny day, it's actually managed to <EM>over</EM>expose things. (Usually almost every shot is seriously <EM>under</EM>exposed.)<br /><br />Is there a reason why even the parts that aren't overexposed have a blue tint? I'm pretty sure sunlight is yellow, not blue.<br /><br />As for correcting it, I've found that even if an image is <EM>nearly</EM> black or <EM>nearly</EM> white, trying to correct the colours afterwards is a hopeless exercise. There's too little precision left to produce any kind of worthwhile image. As you say, the only solution is to get a correct exposure in the first place.<br /><br />Of course, that's kind of the problem, isn't it? From the pitiful LCD on my camera, it's impossible to tell what colour balance an image has. Tilt the screen a fraction of a degree and all the colours change anyway. (It's similarly impossible to tell if anything is in focus. The resolution is far too low.) I'm not really sure what kind of a camera <EM>could</EM> fix this problem.<br /><br />As for adjusting the camera… it's news to me that you can actually do this. Hunting around the menus reveals a setting to control how many megapixels you get, but nothing else.<br /><br />However, in the last few minutes, I have discovered that if you rotate the little dial that I never touch from “A” to “M”, two new menu items appear. One appears to be exposure, and the other is white-balance. Both give me a handful of presets to choose.<br /><br />Changing the white-balance makes the display change instantly, which is nice. Basically it seems to adjust how blue the image is.<br /><br />Irritatingly, changes to the exposure setting have no immediate visible effect. However, I took some shots of the back of my hand, and it seems turning the exposure to the lowest possible setting does make the image darker than the default. Turning it up doesn't appear to have any effect, which is a little odd.<br /><br />Well there we are then. Two new settings that I never knew my camera had. Maybe fiddling with the white-balance could have made my shots a little less blue. But short of taking every shot 6 times (i.e., shooting it with all possible exposure settings), I'm not sure how to get a decent exposure value.<br /><br />As for getting a book — as a matter of fact, I already own one. But it jabbers on about bokah and colour spaces and RAW format and so on and makes no sense at all to me.Orphihttp://blog.orphi.me.uk/noreply@blogger.comtag:blogger.com,1999:blog-36939759.post-9832604379264908062009-04-18T01:00:00.000+01:002009-04-18T01:00:00.000+01:00Continuing would be unnecessary. All of the pictur...Continuing would be unnecessary. All of the pictures you've identified as having colour problems in fact have one problem: they are all overexposed. Remember that a camera has three sensors for each pixel: red, green, and blue. Each sensor 'maxes out' at a particular illumination. If your flower illuminates the red sensor twice as much as the blue sensor, you get a sort of pinky colour. But if too much light reaches the sensors, so that all three max out, all you get is white. Overexposure and underexposure are responsible for most problems with white regions of the image, particularly white skies, and for images looking flat. When the problem is severe enough to make colours look white or black, you can't correct for it in a photo editor afterwards: the information of what colour the object actually was is simply not present in the image. The only solution is to expose the shot correctly, check it on the screen, and if it's wrong, adjust the exposure compensation and take it again.<br /><br />The correct exposure of your image is calculated by the camera - on a compact, it often uses a separate light sensor on the front of the camera, which you have to be careful not to obstruct with your fingers; on a better camera it actually uses the light coming through the lens (TTL). With TTL metering it might have different modes like "centre-weighted", "full frame", or "spot", and you should try taking shots with all of these modes to see the effect. But often the camera will screw it up completely, because the dynamic range - the difference between the darkest and lightest parts of the shot - is too much for the sensor, and it doesn't know (or guesses wrong) which area is most important.<br /><br />Exposure compensation is the tool the camera gives you to correct its mistakes in guessing exposure. The button is usually labelled something like "AE +/-" or "EV +/-". Turning it up makes the camera take a brighter picture, and turning it down makes the camera take a darker picture. After you've used your camera in different situations and sighed at the poorly exposed images you get, you start to get a feel for how the software in the camera works, and in what circumstances it's going to make the wrong decision. For instance, I know that my camera often overexposes shots with lots of cloud in them - cloud is much brighter than it looks - so if I'm taking a picture like that, I'll turn the exposure down a stop.<br /><br />Seriously, this kind of advice is exactly what the book you get from the library gives you, with examples of photos done wrong and what they look like done right. If you really want to produce better images with your camera instead of just claiming to be useless, go to the library and get a photography book, or go to Amazon and spend less than the price of even the cheapest camera on a photography book.Dan Hhttp://surreal.istic.org/noreply@blogger.comtag:blogger.com,1999:blog-36939759.post-8270937031748284582009-04-17T10:39:00.000+01:002009-04-17T10:39:00.000+01:00Well, let's take a look at some of my pictures whi...Well, let's take a look at some of my pictures which are already linked, shall we?<br /><br />After several hours of Googling, it turns out it's actually quite difficult to get Google to find <EM>really</EM> high-quality photographs. It seems most of the images on the Internet are from clueless amatures like me, rather than hardened professionals. But I did find a few images which demonstrate my point.<br /><br />Take a look at, for example, <A HREF="http://www.orphi.me.uk/rev1/04-Photos/2007-04-14/DSCF0023.html" REL="nofollow">this image</A>. Notice how the foreground is completely white. (It should be brown.) Note how the entire scene utterly lacks colour, is cold and flat, and basically looks amaturish. Similarly <A HREF="http://www.orphi.me.uk/rev1/04-Photos/2007-04-14/DSCF0026.html" REL="nofollow">here</A>.<br /><br />Now compare that to <A HREF="http://siteresources.worldbank.org/EXTFORSOUBOOK/Images/forest.jpg" REL="nofollow">this</A>, <A HREF="http://www.woodlandowner.org.uk/g/woodland.jpg" REL="nofollow">this</A>, <A HREF="http://efaller.com/blog/wp-content/uploads/2006/07/fallentree.jpg" REL="nofollow">this</A> or even <A HREF="http://z.about.com/d/forestry/1/0/o/i/ginkgo_leaf.JPG" REL="nofollow">this</A>. Note that in all cases, we have glorious, delicious deep saturated colours. The trees and the grass are solid green. The bark is a strong red. The sky is deep blue.<br /><br />Now take a look at <A HREF="http://www.orphi.me.uk/rev1/04-Photos/2007-04-14/DSCF0014.html" REL="nofollow">this</A>. Can you tell what colour those flowers are? Hint: not white. It hardly compares to the likes of <A HREF="http://www.clivenichols.com/images/advice1.jpg" REL="nofollow">this</A> or <A HREF="http://www.sfbayimages.com/images/400_cdflowers_043.jpg" REL="nofollow">this</A> or even <A HREF="http://pixellens.files.wordpress.com/2008/06/flower-and-beepix12.jpg" REL="nofollow">this</A>, does it? The colour and the composition is nowhere near as good. Obviously cowslips aren't hugely colourful to start with, but the leaves could at least be green and the earth brown.<br /><br />As you can see <A HREF="http://www.orphi.me.uk/rev1/04-Photos/2007-04-14/DSCF0016.html" REL="nofollow">here</A>, my camera stubbornly refuses to photograph small objects in focus. (I'm not sure if that's a limitation of the actual focal length of the lense or just the autofocus software.)<br /><br />What the hell is going on <A HREF="http://www.orphi.me.uk/rev1/04-Photos/2007-04-14/DSCF0038.html" REL="nofollow">here</A>, eh? There's <A HREF="http://www.orphi.me.uk/rev1/04-Photos/2007-04-14/DSCF0046.html" REL="nofollow">more broken flowers</A> (these ones are vivid yellow IRL). Check out this <A HREF="http://www.orphi.me.uk/rev1/04-Photos/2007-04-14/DSCF0010.html" REL="nofollow">really interesting tree stump</A>, <A HREF="http://www.orphi.me.uk/rev1/04-Photos/2007-04-14/DSCF0011.html" REL="nofollow">rendered utterly flat</A> by my photography.<br /><br />Would you like me to continue?Orphihttp://blog.orphi.me.uk/noreply@blogger.comtag:blogger.com,1999:blog-36939759.post-53388658932727198452009-04-16T09:55:00.000+01:002009-04-16T09:55:00.000+01:00So have you I see.
But hey yeah I'd like to see y...So have you I see.<br /><br />But hey yeah I'd like to see your photos and tell you why they're not as awful as you think ;-)<br /><br />Have you got a Flickr account (or similar) or are you going to link from your blog?FlipChttps://www.blogger.com/profile/09449939046593105926noreply@blogger.comtag:blogger.com,1999:blog-36939759.post-28165839422012858582009-04-16T09:45:00.000+01:002009-04-16T09:45:00.000+01:00You've been busy.
Tell you what. How about I show...You've been busy.<br /><br />Tell you what. How about I show you some pictures I took, and you tell me why they ended up looking awful? ;-)Orphihttp://blog.orphi.me.uk/noreply@blogger.com