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-   -   Taking pics in bright sunlight (https://www.scoobynet.com/non-scooby-related-4/89572-taking-pics-in-bright-sunlight.html)

Markus 22 April 2002 05:16 PM

I have a Minolta S304 digital camera. I'm clueless about photography so need some advice with regards to taking pics in bright sunlight.

As an example

http://www.markuswarren.co.uk/artwor...03.2002.35.JPG

This was taken in bright sunlight and to me it seems darker than it should have been. the camera was set on it's 'auto' mode, which might account for this.

What can i do to make the pictures in sunlight as good as possible and not 'dark' like the one above?

AndyC_772 22 April 2002 05:47 PM

In fully automatic mode, the camera will always measure the amount of light and then adjust the exposure so that the average brightness of all the pixels in the metered area is 50%. This gives the maximum possible ability to capture detail in both shadows and highlights, but that's not always what you want.

Suppose you're taking pictures of a snow scene. Most of the picture is therefore supposed to be bright white, but an automatic camera will make it come out grey. For the same reason, a picture taken at night might actually end up too bright.

Underexposure is actually very easy to fix in Photoshop - just adjust the levels or brightness control. Overexposure is much worse because you've actually lost detail in the highlights (the camera can only record that those areas were too bright, but not by how much), so you can never recover them.

To get around this problem, you need manual control over the exposure that your camera uses. For bright scenes like snow, you need to increase the exposure, and for dark scenes you need to decrease it. I found this is quite counter-intuitive at first.

Your example photo is actually well exposed - if you look at the histogram in Photoshop you can see that there are no completely white pixels, which means that you've managed to retain all the highlight detail. You could brighten it in Photoshop, but you'd lose highlight detail in the bumpers of the cars, and the white car in the background would become a bright blob. The right tool for the job is probably the 'curves' adjustment, which lets you brighten up the dark areas and compress (rather than just blow out) the highlights.

Andy.

greyarea 22 April 2002 06:10 PM

I have never used a digital camera, only film, so don’t know for sure that this is the problem. Basically your eyes are much better at handling contrast than film. In bright sunlight shadows that your eyes can see into show up on film as virtually black when the exposure is set for objects in the sun. You can change the settings to correctly expose the shadows, but now the sunlit areas will be overexposed. There is some information on this at http://www.photo.net/making-photographs/light in the Portraits in Sunlight section.

Andy’s suggestion of Photoshop is probably the easiest way to correct it.

Maybe a photo expert has a solution?

James

mega_stream 22 April 2002 07:20 PM

Can you adjust the metre zones?
On my Nikon you can do set it to measure the subject in a number of modes, centre, spot, matrix etc

That way you can get the correct exposure if the main body is in the centre of the frame and not have to have the camera's exposure taken from the whole of the frame...make sence? :D

If you can't adjust the metre reading....I dunno!

AndyC_772 22 April 2002 08:13 PM

Depending on the nature of the scene, it might not make that much difference where you meter the light from. The problem is that the camera doesn't know whether you want the final image to appear particularly bright or dark unless you tell it. That's why most cameras have manual settings that let you override the automatic settings.

Here's an extreme example of how the camera can get confused:

http://home.btclick.com/andrew.cawte/snow.jpg

This shot was taken using the camera's choice of exposure. Despite being a bright snow scene, it's come out grey. There's absolutely nothing wrong with the camera, it just doesn't know that the snow is meant to be white. A quick level adjustment in Photoshop and this shot comes out fine.

My Canon D30 gives two different ways to override the exposure meter. One is to use the meter to determine the 'correct' exposure for the light conditions, but it then gives me the choice of increasing or decreasing the exposure by varying amounts. For example, when I was on holiday in Iceland a few weeks ago, I tended to set the camera to overexpose most photos (compared to the meter readong), because the snow would otherwise come out grey just like the shot above.

The other way is to set the exposure (shutter speed and aperture) completely manually. In this case the light meter isn't used except to provide an indication as to how far from its suggested exposure I am. This mode is particularly useful when shooting panoramas that are going to be made up from lots of photos stitched together - it makes sure that the exposures are all the same, even if each individual shot isn't optimally exposed.

Another time fully manual settings are useful is if the meter can't possibly work correctly. Take a firework display for example - the bright lights might not be present at all until after you've opened the shutter for a long exposure. In this case the meter hasn't got a chance.

In your case, you just need to increase the exposure by a stop or so. You can either use a longer capture time, or a wider aperture.

Films are generally quite tolerant of overexposure - bright highlights retain some detail even if the film's response is non-linear in those areas. It's like recording music to tape with the recording level set too high - it's a bit distorted, but not completely ruined. Disposable cameras with fixed exposure rely on this.

Digital sensors are much less tolerant of overexposure. When a pixel is saturated (bright white), further light landing on it doesn't make any difference (in fact it can cause electric charge to just leak into the surrounding pixels and cause un undesirable effect known as blooming). Detail in highlights is therefore lost forever. You're much better off underexposing shots that have bright highlights, and fixing them in Photoshop.

Andy.

AndyC_772 22 April 2002 08:42 PM

Here's another couple of example shots that illustrate just how difficult it is to get the exposure right on a sunny day:

http://home.btclick.com/andrew.cawte/stonehenge1.jpg

http://home.btclick.com/andrew.cawte/stonehenge2.jpg

These two pictures were taken one after the other, with the difference that the lower image is taken with an exposure four times longer then the upper image. In the top image the sky is correctly exposed, bearing in mind that the sun is actually in the frame. In the lower image, the henge and grass are correctly exposed, but now the sky is completely blown out.

The camera's suggested exposure was halfway between these two shots. Unfortunately, this yields a picture in which nothing is correctly exposed - the sky is still too bright and the ground is too dark. The only real fix in this situation is to take two photos like the ones above, and combine them with some artistry in Photoshop.

Andy.

Hoppy 23 April 2002 01:15 AM

Markus, your picture appears to be perfectly exposed. If it looks dark, it's because you have lots of dark cars hidden in shadow. So there shouldn't be too many surprised there ;) But the parts of the cars that are in sunlight look just fine.

Before you rush to PhotoShop to solve your problems, be aware that bright sunlight (unlike on an overcast day) is very directional and casts harsh shadows. Just move around to the other side of the cars and shoot from the sunny side.

Richard.

[Edited by Hoppy - 4/23/2002 1:16:46 AM]

dba 23 April 2002 06:50 AM

that first pic only looks about 1/2 stop out,it aint to bad! Point the camera at a pavement (as already stated cameras are calibrated to a mid grey) and take a reading.Then point at subject in manual mode using pavement reading.It looks like the meter has exposed for the sky thats all,simple enough to sort. Or next timepoint camera at subject with no sky,keep finger on shutter releas and move up to include sky which should hold the reading (it does on normal cameras,not sure what happens on digi things)

Actually,I haven't a clue,never used a dig thing at all! above advice only works for normal cameras

AndyC_772 23 April 2002 08:55 AM

Hoppy: I agree absolutely with your comments about harsh shadows. I do, however, think of Photoshop as a kind of 'digital darkroom', in which it's perfectly reasonable to adjust exposures, brighten up shadows and so on. After all, if you take a film to a high street chemist they'll scan it and fiddle anyway. It's just part of my workflow - my house is full of framed printouts, all of which have been tweaked in some way or other. (Markus is already painfully aware of my tendency to fiddle with everything in Photoshop - how's the hearse, mate? :D )

I did spend a couple of minutes with Markus' photo, but decided that I actually like the original best. Brightening up the shadows does reveal more detail, but that does necessarily cause a loss of contrast. That reduces its impact IMHO. Maybe a polarizing filter would reduce glare and make for more uniform illumination - I must buy one sometime to play with :)

FYI, here's the result of 5 minutes fiddling with the two shots of Stonehenge above:

http://home.btclick.com/andrew.cawte/stonehenge3.jpg

Andy.

Alpine 23 April 2002 09:48 AM

The simple answer here would be, on most cameras, to just frame the image without the sky, half press the shutter and re-frame keeping shutter half-pressed and then take the shot.. In the extreme example shown the cars would be wonderful but the sky over exposed... with a digi camera who cares.. now take one with the sky perfect and combine the two...

Markus 23 April 2002 10:04 AM

Thanks chaps.

Most informative. Think I'll be looking at the manual mode on the camera tonight!

Andy, the hearse is fine, nice new big red brake calipers as well. hearsetastic you could say ;)

Boost II 23 April 2002 10:38 AM

Shouldn't you have taken the photo from the other side of the carpark. All the drivers side doors will be basking in full sunshine.

Oops - edited to acknowledge someone else said that higher up the page.

[Edited by Boost II - 4/23/2002 10:41:31 AM]

Hoppy 23 April 2002 02:56 PM

Andy, very envious of your PhotoShop skills, mate ;) You seem to be able to alter the laws of physics.

Polarising filter is a good idea, though I don't think it would have rescued Markus' picture where the fundamanetal problem is the contrast ratio which is way too high.

What's needed is a touch of fill-in flash - if you've got a nuclear-powered flash-gun :D

Best regards,

Richard.

DaveD 23 April 2002 10:18 PM

Going back to the original picture - I think the only problem could be that there is too much contrast - ie the shadowy dark areas are black, and the white car is very white.
Otherwise the overall image is correctly exposed.

Photoshop should be able to reduce the contrast in the picture, and could even pick out some of the details in the shadows. Best to load up the picture and have a play with the contrast & brightness settings.

PS: I think the 1st picture of Stonehenge looks better!!

AndyC_772 23 April 2002 11:26 PM

Hoppy: thanks, that's very kind. I've actually seen software specifically for this purpose, ie. taking two shots with different exposures and combining them to give increased dynamic range. In this case, though, it was just a case of doing a gentle transition between the two shots around the horizon, and pasting the stones back in from the brighter image.

Somehow I doubt my flash (Canon 420EX, powered by AA batteries) would have been up to the job :)

Dave: I did try just what you suggested, but couldn't produce a result that was any better than the original IMHO. I'd be interested to see if you or someone else can, and how you did it.

Of the two photos of Stonehenge, I prefer the first one too - the stones have a very strong and recognisable silhouette that doesn't really need any more detail. I have a printout of a similar shot from a slightly different angle which has been converted into B&W, which is a personal favourite of mine.

Andy.


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