Register · Search · Software · Join Upload & Sell · Hosting

	Moderated by: Fred Miranda
	Username   Password FM Forum Rules FM Forums | Lighting & Studio Techniques | Join Upload & Sell    Search Used end    Archive 2008 · Exposure for this scenario

John Power Offline Dedicated FM Upload & Sell: Off p.1 #1 · Exposure for this scenario I was doing a few shots yesterday and I ran across this scenario. Here is one exposure for the sky and 1 for the subject matter. Needless to say, when I exposed for the subject matter the highlight warning was blood red for the sky. Is there a way to expose a scene like this so you get a decent exposure for all elements in one shot? Nov 23, 2008 at 03:11 PM

freetime101 Offline Upload & Sell: Off p.1 #2 · Exposure for this scenario In one shot, other than using fill flash - no You could either use fill flash or bracket the exposures as you have done and combine them either by blending (placing one on top of the other and masking the shadows/blown highlights) or HDR Nov 23, 2008 at 03:31 PM

freetime101 Offline Upload & Sell: Off p.1 #3 · Exposure for this scenario Hope you don't mind but I did a (very) quick photoshop edit of the two images - if you do mind just pm me and I'll delete it. ?t=1227455431 The two original images are slightly different compositions so didnt line up exactly, hence the pretty rough fit... Nov 23, 2008 at 03:52 PM

John Power Offline Dedicated FM Upload & Sell: Off p.1 #4 · Exposure for this scenario That's good. Now if I could figure out exactly how you did that. Nov 23, 2008 at 06:29 PM

freetime101 Offline Upload & Sell: Off p.1 #5 · Exposure for this scenario I placed the lighter photo (with the blown sky) ontop of the darker image, after ajusting the size and rotation to line up the images (they're still not exact but I tried) I used a layer mask to hide the blown sky. You could also use the colour select tool to select whites which would be more accurate (there is a bit above the trees which is still blown). Adjusting the opacity of the top layer to 20-50% while you line them up, then putting the opacity back to 100% is a handy tip. Finally adjust curves (which I didnt bother with) of the individual layers to get them to look right before flattening and saving the image Hopefully this helps, use trial and error until you get it right then post your edited image - good luck Nov 23, 2008 at 06:59 PM

freetime101 Offline Upload & Sell: Off p.1 #6 · Exposure for this scenario Another option is a Neutral Density graduated filter (ND grad), this is a plate of glass held infront of the lens which is darker at the top than the bottom. Though it wouldn't help this image as the darker section is not flat, it will help landscapes etc with a flat horizon a ND grad will make the sky darker and keep the ground light - many landscape photographers use them - they can also be added in photoshop Nov 23, 2008 at 07:06 PM

camey Offline Upload & Sell: Off p.1 #7 · Exposure for this scenario Not sure if the Canon camera can do the same trick but the Nikon D3 has 1.5 - 2.0 stops of overexposure latitude so you just need to shoot one picture somewhere in between these two, process it with high and low exposure settings then combine the images. It used to be much trickier with older digital cameras because they only had at most .5 stop overexposure latitude and pulling up darker areas resulted in excessive noise. Now anyone can do it in a few minutes and some basic Photoshop skills. Nov 24, 2008 at 06:13 PM

bacilonur Offline Upload & Sell: Off p.1 #8 · Exposure for this scenario John, why can't you use a flash? That's one of the best times to have a good speedlite or strobe. Nov 24, 2008 at 06:38 PM

John Power Offline Dedicated FM Upload & Sell: Off p.1 #9 · Exposure for this scenario I did. I was shooting in Av and was shuttling between +3 and -3 FEC. I was also shooting thru a Q39 softbox Nov 24, 2008 at 06:47 PM

shatterkiss Offline Dedicated FM Upload & Sell: Off p.1 #10 · Exposure for this scenario Manual flash and exposure settings are your friend. Meter the scene, set your flash and aperture for the foreground exposure that you want, adjust the shutter speed until you get the background exposure that you want. Done and done. Nov 24, 2008 at 08:15 PM

John Power Offline Dedicated FM Upload & Sell: Off p.1 #11 · Exposure for this scenario Thanks Simon. You are always ready to help and I know it is second nature to you but trying to convert this to reality is not so easy for me. It would be like me saying to you: "illegal search issue? No problem. File your motion to suppress and make sure and include citations that address all the possible exceptions to the 4th amendment warrant requirement that the State might argue. Also, remember that factually there could be waivers of these exceptions so make sure and include questions in your cross examination outline of the arresting officer that negate, if possible, those potential exceptions. Now, having that in mind, go file your Motion" I use manual flash all the time when I am using my studio lights. I pick a Tv setting, take a reading with my Sekonic, get my Av and I am ready to go. But outside, when you say "meter the scene", I am not sure what you mean. I meter a scene by shooting in Av mode and let the camera give me a shutter speed or by shooting in M, selecting an aperture and then adjusting the shutter speed to get the exposure to the middle of the in camera scale. The main confusion for me is that I do not understand how the flash works into the metering equation. Normally with manual flash I am shooting at 125/5.6 with a +2 FEC but it seems that would have blown the band completely out under these shooting circumstances. I get that you are telling me about adjusting the Tv until I get the BG I want, which in this case would be a properly exposed sky (as well as a properly exposed subject), but again, I am not understanding some fundamental concepts here. By the way, I shot over a 100 exposures of this R&B band in several locations and most turned out fine but I did run across a few instances where I was dealing with this sky hence my question. And since you are an expert, are flash issues easier to deal with inside than outside? Nov 24, 2008 at 08:44 PM

shatterkiss Offline Dedicated FM Upload & Sell: Off p.1 #12 · Exposure for this scenario Honestly, in a weird way, I find flash easier to deal with outside during the day than inside: the reason being that the sun provides a lot of very forgiving fill light if you let it. Working indoors, the only light there is light that you've created, which is a lot more pressure. Here's how I would approach this in your situation (and I'm going to put it in general terms, since I really dislike brand-specific versions of general terms, like Av and Tv...they remove us from the fact that we're talking about universal concepts and put us into a proprietary discourse): I'd set my camera into shutter-priority mode at ISO 100 and 1/160th and would take a spot-reading of my primary subject...in this case the guy's face. Say it gave me a reading of f/8. I'd then set my camera back to manual mode at f/8 and 1/160th, set my flash to the middle of its output power range and fire a test shot, then keep testing and adjusting until I had the foreground exposure that I wanted. At that point I could vary the shutter speed to lighten or darken the sky while leaving the foreground exposure intact: 1/125th would give me a brighter sky, 1/250th would give me a darker sky. In my situation, I'd achieve that same end result by using a handheld meter and not having to guess/test for exposure: I take a reading, adjust the shutter to 1/160th, I'm good to go. I don't recommend using auto modes and FEC for situations like this: those are fine for rapidly-changing conditions, but you lose a lot of control. In your case you had stable conditions and were trying to trick your camera and flash's logic into doing what you want. It's so much easier to take their logic out of the loop and simply telling them what to do. For the record, the only time I use FEC is if I'm shooting an event with a flash on a TTL cable and can't count on the lighting conditions to stay constant from shot to shot, otherwise everything is set manually. Nov 24, 2008 at 11:00 PM

John Power Offline Dedicated FM Upload & Sell: Off p.1 #13 · Exposure for this scenario OK. I understand this explanation. I will print this out and set up some practice sessions with my model (read mannequin) under similar circumstances. So your approach is purely manual. No ETTL. By the way, I thought Tv was the universal abbreviation for shutter speed and Av the universal abbreviation for aperture. Nov 24, 2008 at 11:24 PM

turnert Offline Upload & Sell: Off p.1 #14 · Exposure for this scenario John Power wrote: By the way, I thought Tv was the universal abbreviation for shutter speed and Av the universal abbreviation for aperture. No, it's just Canon's silly convention. Tv is particularly annoying. Placing an S on a dial for shutter priority (e.g., Nikon) makes much more sense to me than abbreviating "Time Value". ~Ted Nov 25, 2008 at 02:03 AM

cgardner Online Dedicated FM Upload & Sell: Off p.1 #15 · Exposure for this scenario I have nothing against manual flash, in fact I use it all the time. But ETTL will also work quite well in that situation. See this high speed FP mode flash test I did with my Canon 580ex in ETTL mode (Link to PDF tutorial ) My test used a very similar backlit situation. I shot at f/2.8 in direct sun in Av mode. Here is ambient only, with EC = - 1-2/3 stops needed to correctly expose the highlights in the towel - my proxy for highlight detail. That shot looks underexposed perceptually because the sensor can't record both highlight detail and the rest of the range accurately because the sensor range is about 7 stops and the scene about 10 stops. Then I just reached up and turned on the flash in high speed mode and took another shot. FEC on the flash was set at zero... The ETTL-II evaluative metering balanced the shadow side of the foreground to the ambient lit highlights, as shown by the histogram of just the foreground... So it is quite easy to get good results with ETTL flash if you make the effort to understand how it works. The key factor is getting the ambient exposure correct in the technical sense of not blowing the highlights. That requires understanding that a backlit scene with correctly exposed highlights will have mid-tones and shadows which perceptually look under exposed as in the first shot above. BTW - the point of that test was to show a 580ex has plenty of power in high-speed mode if it is used in combination with wide apertures (the rationale for using it). Not a lot of flash power is needed at 10ft when the lens is wide open at f/2.8. Try shooting at f/2.8 with your manual flash in direct sun Chuck Nov 25, 2008 at 03:58 AM

John Power Offline Dedicated FM Upload & Sell: Off p.1 #16 · Exposure for this scenario You know Chuck, now that you mention it I realize I did not have my flash in high speed sync even though I taped a note on it that says "HS sync in AV outdoors" So much for notes. (This is what happens when you practice law all week and try to act like a real photographer on week-ends) I am going to try and duplicate the scene and try both methods. Nov 25, 2008 at 01:16 PM

cgardner Online Dedicated FM Upload & Sell: Off p.1 #17 · Exposure for this scenario You can simply leave the flash set to high speed mode when shooting outdoors. The flash communicates with the camera and will switch back and forth as needed from "single pop" to high speed mode "strobing" mode as Av forces shutter speed past the camera x-sync limit. The caveat is that when shooting in Av mode you do need to be cognizant of what shutter speed the camera is selecting so you can anticipate how flash range will decrease when the shift to high speed mode occurs. For example if the camera is at f/8 and the scene pushes shutter speed in Av mode to 1/300th High Speed FP flash mode will be enabled automatically and you might see a underexposure using the FEC set if the flash is maxed out. If the flash is maxed out adding more FEC will have no effect. What you'd need to do is open the aperture more which would increase the effective range at maximum High Speed FP output levels. The point of the test was to dispel the notion that High Speed FP mode doesn't have the power to work outdoors. That is certainly true if the camera aperture is set at f/11 as is would be for manual flash outdoors, but the whole point of High Speed FP is the ability to use wide apertures outdoors to limit DOF. So in that respect trying to use it at f/11 is like trying to pound a nail with a screwdriver: the wrong application of the tool. If you use High Speed FP mode with wide apertures range is less of an issue because with each f/stop the lens is opened the effective range at max. power doubles. I was intentionally using Av as part of that test, but if you read my other fill flash tutorial you'll see the strategy I use for difficult to meter scenes is to first use the camera metering in Av mode like a spot meter to measure the highlights in a scene for the ambient, then I switch to manual mode using those settings to "lock in" the ambient portion. Once the ambient is locked in at the desired f/stop and shutter speed its simply a matter of taking a benchmark shot with flash, then adjusting FEC (in ETTL) or power level (in M) as needed to achieve the desired balance. High Speed FP also works in Manual and with multiple flashes in a Master / Slave configuration. The reason that metering strategy is needed is because the camera meters off the viewfinder with only 35 relatively large zones (more on Pro models), and within each zone the reflections off the subject are averaged to some degree. That is why camera metering, even evaluative, will tend to overexpose the ambient in back-lit scenes with very small areas of highlight. The wider the the crop the less likely it is that a highlight which has detail which is important will fill a metering zone and bias the exposure correctly in Av mode. Chuck Nov 25, 2008 at 02:07 PM

	end FM Forums | Lighting & Studio Techniques | Join Upload & Sell end

You are not logged in. Login or Register

Username   Password   Lost your password?