Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
04-04-2010, 10:34 AM   #1
Junior Member




Join Date: Nov 2009
Location: mississippi
Posts: 38
How is this kind of photo taken?

How do you take a photo to get proper exposure of a scene where there is a dark foreground and a lit up bacground so that the foreground is properly exposed and the background not blown out?

I was reading in a book and the guy says that he takes a meter readin off of the dark foreground and then adjust his shutter speed and recomposes but I am a little confused on how to do this. What mode would you do this in? M,av,tv,sv, or p mode. Can anyone give a slow learner a little clearer instruction on how to take this type of photo?

Thanks Much...

04-04-2010, 10:48 AM   #2
Veteran Member
ytterbium's Avatar

Join Date: Jan 2008
Posts: 1,076
If the foreground is close enough to be lit by the camera flash, i'd simply use fill flash.

If not, then it gets tricky. Either way most likely a post processing or special filters are needed.
One way would be using ND Grad filter do mask the bright background.
Another way would be choosing some average exposure value (between foreground and background), shooting in raw and do some fill light post processing. Either with curves, dodging, layers or special tone mapping tools.
Alternatively a mapped HDR image can be created, if the light differences are big.

Hope this helps... or you were looking for a more practical solution?
04-04-2010, 11:42 AM   #3
Pentaxian
Wheatfield's Avatar

Join Date: Apr 2008
Location: The wheatfields of Canada
Posts: 10,132
I think you've about covered the practical solutions...
04-05-2010, 12:59 PM   #4
Pentaxian




Join Date: Jul 2009
Location: Seattle
Posts: 7,089
If there is too great a range between the dark and the bright, you'll never get there unless you combine several exposures or use a graduated ND filter as yetterbium suggested. I assume you're using a DSLR. So why not take a picture, look a the results, adjusting the EV compensation, take another picture and repeat until you get what you're after?

04-05-2010, 08:59 PM   #5
Veteran Member
WMBP's Avatar

Join Date: Dec 2006
Location: Dallas, Texas
Photos: Gallery
Posts: 2,496
QuoteOriginally posted by dehanson1 Quote
How do you take a photo to get proper exposure of a scene where there is a dark foreground and a lit up bacground so that the foreground is properly exposed and the background not blown out?

There are a couple of ways to approach this common problem. And the precise solution to the problem depends on the precise problem, that is, it depends on a number of different variables, including
  1. the exposure value difference between the bright background and the shadowy foreground;
  2. your distance from the subject in the foreground;
  3. whether you are going to bounce your flash;
  4. whether you're indoors or outdoors and the amount of ambient light;
  5. required depth of field...

...among other things. I will add that different photographers use their camera and flash in different ways.



Neil von Niekerk's approach

One of the very well known online experts on the subject of hot-shoe flash photography is Neil von Niekerk. His "Tangents" web site (formerly known as Planet Neil) is a great resource. He's also written a very useful book on flash photography. Anyway, here is how I think von Niekerk would advise you to proceed.
  1. Turn the flash unit off for the moment.
  2. Put your camera into full-manual (M) mode.
  3. Calculate a correct exposure for the background. There are different ways to do this, but one easy way is to put the exposure mode into spot exposure (rather than center-weighted or matrix), point the center of the view finder at the background, and adjust your settings until you get a balanced "correct" exposure for that spot. On some cameras, you can simply hit the green button next to the shutter to get a correct exposure correctly.
  4. Recompose, focus, and take a photo. In this photo, don't worry that the foreground is too dark. What you want to see here is that you've got the background properly exposed.
  5. Check out the camera settings at this point. If the shutter speed is faster than 1/180th sec (the max flash sync speed), adjust shutter and aperture in complementary ways so you maintain the same exposure, but get the shutter down to 1/180th sec.
  6. NOW you turn the flash unit back on. Set its flash mode to P-TTL.
  7. Point the camera at the subject, focus, and shoot.
  8. With any luck, you'll have the result you want. The background ought to be correctly exposed, but you might want to adjust the exposure of the foreground subject. You do so by dialing in an appropriate amount of flash exposure compensation, on the flash unit itself. For example, if the subject is a little too bright (overexposed), you might dial in -0.5 or -1.0 EV flash compensation. On the other hand, if the subject is still too dark (underexposed), dial in +0.5 or +1.0 EV flash compensation.

Niekerk's method is, I think, the easiest one to understand and use of those I'm familiar with. The basic idea is, you control the camera exposure manually, then you let the TTL exposure system (in which the flash unit and the camera cooperate with one another) take care of the details. It generally works pretty well.



An example

Here's a simple example. My daughter's kitten is sitting in a chair in a bedroom. I want to photograph the kitty, but I don't want the windows to be completely blown out (way overexposed). So first, I calculate a correct exposure for the windows, especially the one on the right, with the curtain.



Yeah, I know. You can't even see the cat in there. That's okay. Look at the curtains on the right, or through the blinds on the left out to the deck. Those areas are correctly exposed. I'm in M mode on the camera. Settings are 1/180th sec, f/6.7 and ISO 800.

NOW I turn on the flash, in P-TTL mode. I bounced the flash off a white wall behind me and to the right, in an effort to match the direction of the flash with the light from the window on the right. The first shot that I took was not too bad:



This photo has not been improved in post-processing, but it could be quite easily. It would be easy in Lightroom to use the adjustment brush to lighten up the chair and the kitten a little, and the result would be a satisfactory shot.

However, I decided that I wanted to make the cat a little brighter still. In retrospect, I wish I had left the shutter speed at 1/180th sec and opened up the aperture instead; but what I did was the opposite—I left the aperture at f/6.7 and slowed the shutter down to to 1/90th sec. Here's the result:



This shot has obviously been given a little post-processing and has been cropped.


Final thoughts

Sounds like a lot of trouble, but it's really not, once you get the hang of it. A couple of minutes passed between the first shot and the last one, but that's because I was waiting for the cat to strike a better pose. If I were shooting an event, this could all be done in a matter of a few seconds. And if I was in a hurry, I would not bother actually to take the first shot.

As I said earlier, there are other ways to skin this cat. Woops, don't tell my daughter I said that. I meant, there are other ways to take this photo.

Will
04-06-2010, 06:57 AM   #6
Junior Member




Join Date: Nov 2009
Location: mississippi
Posts: 38
Original Poster
P-TTL Mode?

Wow.Thanks for all that info. Just one question. What is P-TTL mode?
04-06-2010, 07:23 AM   #7
Veteran Member
WMBP's Avatar

Join Date: Dec 2006
Location: Dallas, Texas
Photos: Gallery
Posts: 2,496
QuoteOriginally posted by dehanson1 Quote
Wow.Thanks for all that info. Just one question. What is P-TTL mode?

Ah, good question. I'll do my best to be brief here.

"TTL" stands for "through the lens." It's often used in connection with exposure metering. TTL metering means that the camera's meter is collecting exactly the light that will be coming through the same lens and hitting the sensor.

Now, a while back, TTL flash metering originally worked somewhat crudely. You'd click the shutter, the flash would fire, the TTL meter would monitor the light coming in, and when it determined that enough light had reached the sensor to create a correct exposure, a signal would be sent to the flash to quit, and the flash would shut off. Sounds complicated, but apparently it worked pretty well.

And then camera manufacturers came up with something that purports to be even better. It's called something different by different manufacturers. Canon calls it E-TTL (I think the E stands for evaluative). Nikon calls it I-TTL (I for intelligent). Pentax calls it P-TTL. I've always thought the P stands for Pentax but somebody here recently told me it stands for something else.

Anyway, the key thing about these newer systems is that they all use a preliminary flash to determine exposure. In other words,
  1. You click the shutter, which tells the camera you want to take the picture NOW
  2. The camera tells the flash unit to send out its exposure-evaluating pre-flash
  3. The pre-flash occurs
  4. The camera evaluates the information gathered from the pre-flash and determines how much light it REALLY needs to send out for a correct exposure, given the camera's settings
  5. The shutter finally opens
  6. The actual flash occurs
  7. Shutter closes

Notice that steps 1-4 occur after you click the shutter, but before the shutter opens. In other words, these steps happen really fast. Normally, if you use front-curtain flash (the default or normal setting for most photographers) you simply won't see the pre-flash at all. If you want to see it, put your camera into rear-curtain flash and use a long exposure like half a second or a whole second. Then you'll see the pre-flash, you'll hear the shutter open, and at the end of the exposure time, the flash will fire again—that second flash being the one that actually exposes the shot.

There's more to the various X-TTL systems than that. Nikon's in particular seems to have quite a few clever options. But the pre-flash is the key element of the systems.

There is one potentially significant problem with the pre-flash. Almost nobody can actually distinguish the pre-flash from the real flash mentally, that is, almost nobody realizes there are actually two flashes. But some people's reflexes are so quick they they will blink in response to the pre-flash. I had a bride whose father (himself an avid amateur photographer) warned me that his daughter was a blinker, and he was right. I had a heck of a time getting good photos of that bride in which her eyes weren't half closed. There are a couple of solutions to the blinking problem, but the basic solution is, don't use the X-TTL system to control your flash. Use the flash instead either in manual (M) or auto (A) mode. Neither of these modes uses a pre-flash.

The original TTL flash systems didn't use a pre-flash either, as I noticed above. Some flash units support either older TTL or newer X-TTL, but generally, you don't get to choose which you prefer. I don't use my *ist DS for flash photography much but I don't think it supports P-TTL; when I put the flash unit on the *ist DS, I get old-fashioned TTL. If I put the same flash unit (say, a Pentax AF 540 FGZ unit) on my K10D/K20D bodies, I get P-TTL willy-nilly.

Hope that helps.

Will
04-06-2010, 08:00 AM   #8
Pentaxian
Lowell Goudge's Avatar

Join Date: Jan 2007
Location: Toronto
Photos: Gallery | Albums
Posts: 15,399
there is one additional way, not mentioned here, which is available on the K7 at least. I will assume you are shooting JPEG for this.

There are additional functions for highlight detail preserve, and shadow detail preserve, which work independant of each other.

If you consider the middle exposure is at a histogram level of 127, shadow detail preserve modifies the exposure below this level, adding about 1 stop of additional dynamic range between hostogram 25 anmd 127. Normally there are about 2.5 stops in this range, and shadow protection adds an additional stop of detail.

Highlight preservation does the same above 127, adding an additional stop of dynamic range between 127 and about 225, again expanding this from 2/5 stops to 3.5 stops.

By using both, and using average metering, you will get a result that carries as much detail as possible without using either graduated filters or HDR techniuques.

They combine to essentually act as a super contrast adjustment (reduction).

04-06-2010, 08:00 AM   #9
Veteran Member
WMBP's Avatar

Join Date: Dec 2006
Location: Dallas, Texas
Photos: Gallery
Posts: 2,496
more info about P-TTL and Pentax flash

There's a ton of info about flash photography on the Internet, and some of it is actually pretty good. The single most useful site, for most photographers, is probably Neil von Niekerk's Tangents blog, which I mentioned earlier. The reason I recommend this site so strongly is that Niekerk is primarily concerned with on-camera flash, and this is how most photographers use their flash units most of the time.

The next big step (after you master on-camera flash) is to get the flash OFF the camera. For more info about that, most people would recommend strobist.com. Personally, I have always found strobist.com somewhat poorly written and confusing, and most of what I know about off-camera flash has been learned by trial and error, with the help of other photographers, and through some other reading. But strobist.com is popular, perhaps because the very idea of getting your flash off the camera comes as a revelation to many photographers.

Finally, I should mention the best resource available on Pentax flash, which is a site built by a member of this forum (mattdm). Here's a link to the P-TTL info page, from which you can navigate to other pages with more info than you can shake a stick at.

Pentax P-TTL Flash Comparison: Further P-TTL Information

Tremendous resource.

On the not very recommended list, I'm afraid, is the operating manual that comes with your flash unit. I have several flash units now but I'm thinking particularly of the manuals for the Pentax AF 540 FGZ and the Metz 58AF. The operating manuals aren't useless, indeed, you almost HAVE to read the manuals to figure out how to use the units. But they are just awful. There was not long ago a somewhat heated argument here at pentaxforums.com about whether P-TTL works if the flash isn't in its default straight-forward 90° angle posture. It's the kind of question that should easily have been resolved by a look at the operating manual, but instead, both sides of the debate were quoting the manual in their favor.

Will
04-06-2010, 08:21 AM   #10
Pentaxian
LeDave's Avatar

Join Date: Jun 2009
Location: Minneapolis - St. Paul
Photos: Gallery
Posts: 2,901
I am not a big pro at back-light and have always wanted to know the proper way to do it also. I have a question myself.

Without using fill-flash, is there any way possible to do a sunlight back-lit shot without a overblown sky but yet still retain a small to fair amount of detail in the foreground whether it's under-exposed or not?

Here is some of my search's that I am wondering how they've done it. I'm not quite sure how these are done whether it was with flash or not, but if they can be done w/o flash then I'd love to know; otherwise is the chances are that they only be done using fill-flash?

I did not take these photos, they are for reference only.



04-06-2010, 09:05 AM   #11
Veteran Member
WMBP's Avatar

Join Date: Dec 2006
Location: Dallas, Texas
Photos: Gallery
Posts: 2,496
QuoteOriginally posted by LeDave Quote
Without using fill-flash, is there any way possible to do a sunlight back-lit shot without a overblown sky but yet still retain a small to fair amount of detail in the foreground whether it's under-exposed or not?

Since both of these look like pro commercial shots, there was probably a LOT of lighting equipment involved—more than it's useful for most of us to worry about. I'd bet a nickel that the first photo you linked to, did use flash, although I'm also pretty sure the flash was (a) off camera and (b) very carefully directed. I say this because the couple's hips and sides are much darker than the man's face, that is, the lighting shows contrasts that are hard to get when you rely entirely on reflected light. But I don't know for sure. Even if there was flash, there was probably ALSO a reflector, off to the right. That's why the man is illuminated on his face, chest and forearms, while the woman is lit on her hair and the back of her arms.

The basic problem is conceptually rather simple. Your camera can record a dynamic range of only N stops. (N is somewhere around 5.) This is the difference between the brightest and darkest elements of the photo that your camera's sensor can record with detail in the same shot. When the dynamic range of the scene is greater than N, you have only two choices:
  1. Sacrifice something at one end or the other of the exposure range, that is, either blow out some highlights in order to retain detail in the darker parts of the scene, or allow the darkest areas of the photo to become undifferentiated pure black in order to retain detail in the brightest areas (for example, clouds)
  2. Adjust the light being thrown on the scene so as to reduce the dynamic range.
As an example of option 1, going back to my cat photo earlier in this thread, if I shot that without flash (and without using a reflector), I would have had no choice but to blow out the windows, in order to get the cat in the chair properly exposed. This isn't necessarily a bad thing. Actually, it can be a nice effect. I should add that the reverse can also be effective, that is, in some cases—say, couple embracing with the sun behind them—it's perfectly okay to expose for the background and leave the couple entirely in silhouette. Wouldn't work for my shot of the cat in the chair because the silhouette wouldn't be interesting. But can be a nice way to photograph a couple.

But many photographers will want to use the second option: reduce the dynamic range. This means you have to use some equipment besides your camera, because you have to do something about the light. Something as simple as a neutral density filter can help, a little. Slightly more difficult to use but still low-tech, is the reflector (or screen). The final option is added artificial light, that is, flash.

Shooting portraits outside in the sunlight, as I do fairly frequently, I use reflectors and flash.

If I was going to try to mimic your first shot (the couple embracing with the sun in the background), I'd go about it pretty much the same way I went about shooting my cat. I'd put the camera into manual mode and expose for the sky. I'd be careful to overexpose the sky but just a little. It's okay for the sun to be blown but I don't want to lose the clouds. Now I'd use a reflector off to the right, to bounce sunlight from over the woman's left shoulder into the face of the man. Because it looks like the sun is pretty bright, the reflector might throw enough light on the couple to make me happy. If it didn't, I would add a touch of fill flash in order to keep some detail in their bodies, that is, to prevent them from becoming silhouettes. Actually, I would probably turn my flash on to start with, on the theory that sometimes the fill-flash simply has no effect at all (which might not be a bad thing).

One question I'm not sure I know how to answer is whether I'd use normal sync or high-speed sync. I'd just have to try it and see. That's true with an awful lot of flash photography. You have to learn principles, rather than recipes. It's okay to say that, oh, f/4 and ISO 400 is a good default setting for your aperture and ISO if you're using on-camera, bounced flash indoors. But those settings don't always work. And you still need to set the shutter speed. And you still need to know how to bounce the flash.

Will
04-06-2010, 09:41 AM   #12
Pentaxian
Lowell Goudge's Avatar

Join Date: Jan 2007
Location: Toronto
Photos: Gallery | Albums
Posts: 15,399
QuoteOriginally posted by LeDave Quote
I am not a big pro at back-light and have always wanted to know the proper way to do it also. I have a question myself.

Without using fill-flash, is there any way possible to do a sunlight back-lit shot without a overblown sky but yet still retain a small to fair amount of detail in the foreground whether it's under-exposed or not?

Here is some of my search's that I am wondering how they've done it. I'm not quite sure how these are done whether it was with flash or not, but if they can be done w/o flash then I'd love to know; otherwise is the chances are that they only be done using fill-flash?

I did not take these photos, they are for reference only.



what about a reflector between the camera and subject.

reflect sunlight back on to the fornt of the subject, to reduce the shadows.
04-06-2010, 10:09 AM   #13
Pentaxian




Join Date: Jul 2009
Location: Seattle
Posts: 7,089
Taking a picture into the Sun, if not done by trial and error, you need to measure the light and see how many stops difference there are and decide what is going to go accent black or accent white if it exceeds your camera's capability. And no doubt it will without some fill or refected light. Having ever used a one-degree spot meter, for example, helps you understand that. Here is an example of using a one-degree spot meter to meter a scene. You know in advance of taking the picture what is accent black or accent white with it on your first shot - and only shot in these cases. The pictures turned out just as I expected them to and they didn't need any fancy graphics editor wizardry either:




Last edited by tuco; 04-06-2010 at 10:22 AM.
04-06-2010, 10:24 AM   #14
Veteran Member
WMBP's Avatar

Join Date: Dec 2006
Location: Dallas, Texas
Photos: Gallery
Posts: 2,496
Tuco, those are really nice shots. I'm filled with admiration.

But just for the record—and to help out the OP—I don't suppose you used flash in these shots, and if you used some sort of reflector, it must have been the size of a truck. I would think that your wonderful landscape shots are the kinds of shots for which neither flash nor reflectors are going to be much help. Flash would have diminished those wonderful shadows in the foreground of both shots but wouldn't have been able to make a difference to most of the scene. For these shots you really did have to squeeze the most out of the camera's sensor. Did you use a filter?

Will
04-06-2010, 10:35 AM   #15
Pentaxian




Join Date: Jul 2009
Location: Seattle
Posts: 7,089
QuoteOriginally posted by WMBP Quote
Tuco, those are really nice shots. I'm filled with admiration.

But just for the record—and to help out the OP—I don't suppose you used flash in these shots, and if you used some sort of reflector, it must have been the size of a truck. I would think that your wonderful landscape shots are the kinds of shots for which neither flash nor reflectors are going to be much help. Flash would have diminished those wonderful shadows in the foreground of both shots but wouldn't have been able to make a difference to most of the scene. For these shots you really did have to squeeze the most out of the camera's sensor. Did you use a filter?

Will
Thanks. No fill light was used. I used an Pentax O2 (orange) filter
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, foreground, mode, pentax help, photo, photography
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
What kind of Bird is this? Eastern Shore Charlie Post Your Photos! 3 01-06-2009 02:25 AM
Something kind of different mel Post Your Photos! 19 05-30-2008 07:14 PM
The kind of photo that makes your mouth water... paden501 Post Your Photos! 9 02-13-2008 07:02 AM
What kind of tree??? Ed in GA Post Your Photos! 7 10-20-2007 01:01 PM
Two of a kind... pog Post Your Photos! 2 12-09-2006 09:30 AM



All times are GMT -7. The time now is 07:51 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top