Overexpose with flash to reduce noise?

Recently took pictures at a party with somewhat dim lighting. with f2.8, ISO 1600 or 3200, shutter speed came out to about 1/40. I hate shooting group shots (all subjects on same plane, so f2.8 was fine) with an ISO that high because of the noise. Attempts to reduce noise makes the faces look slightly blurry.

I accidentally took a shot with my 580ex at full strength, bounced up to the ceiling and majority of the image almost looked blown out. However, in LR, I dropped the exposure down almost 3 stops and the image came out looking good. When zooming in at the eyes at 1:1, there was basically no noise at all. Definitely looked better than my original attempts to properly expose in camera.

Should I start overexposing all my shots by bumping up my flash from now on?

The setting you are using is fill light. You can't use fill light when getting the proper exposure reading means that your shutter speed would be too low and the DOF is too wide open. You need to underexpose to the ambient light by -2 stops the most. Use a high ISO. keep you shutter speed below your max flash sync speed. Just let your flash does its magic.

Ceiling bounce flash with a beige color index card. 1/160s shutter speed. F 5.6. ISO 1600.

IMAGE LINK: http://www.oneimagingp​hotography.com …092534&k=V29Jhp​H&lb=1&s=A

I dont know if I would over-expose as that runs the risk of blowing highlights but using ETTR exposure wont hurt. Actually just using a flash period will help with noise since your ISO will drop considerably.

Nature Nut wrote in post #15131391
I dont know if I would over-expose as that runs the risk of blowing highlights but using ETTR exposure wont hurt. Actually just using a flash period will help with noise since your ISO will drop considerably.

No, no, no...you need ETTL because the subjects you are shooting aren't staying in one place. You can't constantly changing your flash power output depending who you encounter in an event. You can be called up to shoot someone any time, in any part of the room with different ambient condition.

If you overexposed with the flash by 3 stops I'm guessing you may have almost eliminated the ambient light. If that's the case then you may want to consider shooting with a lower ISO, stopping down a bit ( if you prefer) and using a faster shutter speed ( if you prefer) instead.

Well personally I don't think overexposing the flash 3 stops to avoid noise is a good practise. You run the risk of blowing out important images you may not be able to recover.

Noise is all about correct exposure. What mode was your camera in? The shutter came out to about 1/40 sounds like AV. Most photogs shoot indoor flash in camera on manual. Flash will be the dominant light source. In AV flash becomes fill.

Good advice by TooManyShots. Shooting at a higher ISO will balance the flash and ambient. Correct flash exposure will reduce that noise on the subjects..

Using ETTR (Expose To The Right) techniques in low light will definatly help. How far you push the exposure is a call you have to make. You need to push the exposure to the point just before "important" highlights start to blow. You may have specular reflections or other light sources in the image that it doesn't matter if you burn out as they have no detail in them to start with. The more light you can let into the camera the better your signal to noise ratio will be, high SNR low amounts of percivable noise.

Going up a stop or two with ISO and pulling the same in post will actually give better noise results than shooting "normally" at the lower ISO value. Pushing the exposure level at all in post at any ISO value (including ISO100) will result in noise appering in the shadows.

All of the above applies no matter if you are using ambient only, fill flash or using flash as the main lighting and shooting in P, Av, Tv or M modes. With flash shooting ETTR can be applied if you are using a fully manual flash setup or if you are using the Canon ETTL II automatic settings. It is just a matter of setting up your camera and lighting (whatever the source) to give the level of exposure that you need to get the results you want. ETTR is just another technique you can use to get better results, although one personally I would recommend to all KEEN amatures to use as much as possible. I does of course requrie you to shoot RAW so is not suited to several situations that professional Photographers find themselves in.

Alan

digital paradise wrote in post #15131432
Well personally I don't think overexposing the flash 3 stops to avoid noise is a good practise. You run the risk of blowing out important images you may not be able to recover.

Noise is all about correct exposure. What mode was your camera in? The shutter came out to about 1/40 sounds like AV. Most photogs shoot indoor flash in camera on manual. Flash will be the dominant light source. In AV flash becomes fill.

Good advice by TooManyShots. Shooting at a higher ISO will balance the flash and ambient. Correct flash exposure will reduce that noise on the subjects..

I agree, shoot in manual with higher ISO's and reasonable shutter speed to balance ambient and flash. I've never purposely overexposed a indoor flash shot

Maybe I'm missing something here, but if you have the margin of light to overexpose by 3 full stops, why not drop three stops of ISO for noise reduction and just take that exposure?

I keep hearing/reading the secret to low noise high ISO shots is to overexpose and dial it back in post, but if you have enough light that you can overexpose without having problems with slow shutter or wide aperture, why are you using high ISO? Am I missing something?

Matt

mattkrass wrote in post #15134066
Am I missing something?

Matt

http://en.wikipedia.or​g/wiki/Exposing_to_the​_right

The general idea is to maximize the light data from our severely limited dynamic range sensors. Dialing it back looks good, trying to bring up underexposed areas will bring the color noise monster out of the closet fairly quick depending on camera. Its not without its flaws and criticism of course.

Here is a thread on it
https://photography-on-the.net …/showthread.php​?p=8534003

Nature Nut wrote in post #15134079
http://en.wikipedia.or​g/wiki/Exposing_to_the​_right

The general idea is to maximize the light data from our severely limited dynamic range sensors. Dialing it back looks good, trying to bring up underexposed areas will bring the color noise monster out of the closet fairly quick depending on camera. its not without its flaws and criticism of course.

So, if I am understanding you correctly, a photo shot at ISO 400, 2 stops over exposed to the right, but not clipping anything, then dialed back 4 shots will come out cleaner than the same shot at the same exposure settings at ISO 100? Is this correct?

I have tried to apply the doctrine of overexposing and dialing back in post for high ISO shots, but the only time I ever need high ISO shots are when I can't even get a normal exposure, let alone overexposure.

I'm not saying you're wrong, I just don't understand why you're right.

Matt

mattkrass wrote in post #15134113
So, if I am understanding you correctly, a photo shot at ISO 400, 2 stops over exposed to the right, but not clipping anything, then dialed back 4 shots will come out cleaner than the same shot at the same exposure settings at ISO 100? Is this correct?

I have tried to apply the doctrine of overexposing and dialing back in post for high ISO shots, but the only time I ever need high ISO shots are when I can't even get a normal exposure, let alone overexposure.

I'm not saying you're wrong, I just don't understand why you're right.

Matt

It is more apt for dynamic lighting situations. The idea I have taken away from it is that if you have a few clicks of SS or aperture to sacrifice to expose a little more then regardless of a higher ISO your image has a better chance of coming out clean. Its basically compensating for lower end cameras that get noisy fast but need to use higher ISO's. Noise shows up quicker in darker areas needing to be lightened up is all. Under normal circumstances It is not essential but can still be used. How much you expose to the right of center is a personal pref and situation dependent.

Edit: to answer your question, the lower the ISO the better, ETTR is compensating for ISO noise, not using it to achieve ETTR. Hope that makes sense.

Nature Nut wrote in post #15134137
Edit: to answer your question, the lower the ISO the better, ETTR is compensating for ISO noise, not using it to achieve ETTR. Hope that makes sense.

That's what I thought, which is why I'm confused. I can't think of any situation where ETTR is an option, where I would also need high ISO. Any extra leeway I had on the exposure I'd put towards lowering my ISO setting.

Maybe I'm just dense today could you suggest some situations where using a high ISO and ETTR makes more sense than lowering your ISO?

Matt

mattkrass wrote in post #15134168
That's what I thought, which is why I'm confused. I can't think of any situation where ETTR is an option, where I would also need high ISO. Any extra leeway I had on the exposure I'd put towards lowering my ISO setting.

Maybe I'm just dense today could you suggest some situations where using a high ISO and ETTR makes more sense than lowering your ISO?

Matt

When shooting a low key image and you know most of the info will be on the left of the histogram for your final product and you have a lot of room to expose to the right.

mattkrass wrote in post #15134168
Maybe I'm just dense today could you suggest some situations where using a high ISO and ETTR makes more sense than lowering your ISO?

Matt

For my purposes it is usually when I am shooting wildlife in the shade, birds in dim lighting or shooting a landscape in the woods with rays of sunlight peering through. For those I try to get closer to clipping the highlights than balancing the scene where there may be dark areas that need a little exposure boost in post.

For wildlife you need a fast SS so thats locked in high, even wide open light can be sparse at times so a high ISO is needed unless you own a fast (read: expensive) lens. So in the end your stuck with something like 1/1000, f 5.6 and ISO 3200 trying to capture a deer in the middle of the woods. For this situation you would want to over-expose slightly as any slightly darker shadows you wish to bring up in post will present noise which can soften important detail.