Exposure/ISO Question

[marc s]

I'm not sure if there is a problem or not. Whatever, the case, I don't really like the outcome.

 

Here are three pictures I took with my 20D, all of which are at an 800 ISO in our living room with the lights

on. All are at f4 with my camera meter showing about 1 stops underexposed. All are at 1/60.

 

1) Photo 1 is without flash.

2) Photo 2 is with flash but with a diffuser.

3) Photo 3 is with the flash bumped up to +1.

 

Now I know that they should be a little underexposed since it's down a stop. But even at 800 ISO and

approximately ? I could shoot lower shutter speed but, of course, I'm risking blur.

 

It's been a while since I shot film. However, I can't remember my film shots ever coming out so dark even

with 400 speed film.<div></div>

[marc s]

...and my apologies to the moderator. I'm not sure how to post three pictures together;

therefore, the three separate postings.

[kelvinphoto - arlington, t]

What do you don't like about the results?

[wedding-photography-denver]

What are you expecting as an outcome? It looks like you are getting what you paid for. When you shoot at -1 stop, and the cameras default is to underexpose, you will not get good exposure. The thing about film is you never did the PP work to bring it back up to normal exposure.

[marc s]

I guess I was hoping for some brighter images. You know...something with the sharpness,

clarity, and exposure of an Ansel Adams picture...

 

No, seriously, though, I was thinking it should be a little brighter at an 800 ISO, especially

with flash. You guys are probably right. Perhaps I'm expecting a little too much.

 

And yes, Photoshop can do wonders.

 

Thanks

[picturesque]

Do some reading about Canon flash at photonotes.org/eosflash and planetneil.com. Plus look up my simple guide to using the 580EX with the 20D.

 

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00HOSA

 

It is in the middle of the thread. It might help (in my humble opinion).

[marc s]

Great post Nadine.

 

Your understanding and explanation of the 580 is very helpful. I'll have to play around with it

some more. Have you ever considered writing a tutorial on this?

 

Thanks

[think27]

Marc

 

Number one:

 

It tells you exactly what to do to post an image properly as you go along the steps to post an image..

 

511 pixels or less

 

CAPTION in the caption box

 

Number two - Please read the rules for posting on the Wedding Forum...

 

Post one image only. Then post a link to where the other photos are in your folder or on your website.

 

You can put three images together...

 

Go into photoshop and make a new file - cut and paste the other photos into it. Then resize the file as 511 pixels in width. Post a CAPTION.

[marc s]

Thanks Mary.

[picturesque]

Well--it's kind of that simple, and with those articles I mentioned, you should be able to figure it all out. Picture 3 looks about right on her face, which is the closest thing to you. I agree with David re film and the lab processing for you. ISO 800 shouldn't have anything to do with whether the flash exposed correctly unless you were using AV or TV, where the flash generally acts to support the ambient exposure rather than becoming the main source of light. I'm assuming you were using manual mode on the camera. Plus, flash will freeze motion, but you have to underexpose the ambient for this to happen. When you read the planetneil article, especially read "Dragging the Shutter". In your example, you have underexposed the ambient by a stop, which usually isn't enough, with flash, to freeze motion.

[marc s]

How's this?

[marc s]

My goof. Here's a retry.<div></div>

[marc s]

Yes, all the shots were in manual. I'm going to play around with it a bit tomorrow and

experiment with planetneil and your posting. Again, thanks.

[aaron_lee___minneapolis__m]

What are you expecting, exactly? Great dramatic lighting from 1 incandescent bulb in the room with on-camera flash?

 

I might guess your meter is getting fooled by the large white paper and the blonde hair(did I remember that correctly?) in the frame. I would recommend choosing another metering mode.

[marc s]

Hi Aaron,

 

I guess I should have explained that these were some quick test shots with my daughter. I

wasn't trying for anything artsy, that's for sure!

 

I was simply a little disappointed with the 800 ISO results. That's all. (For what it's worth,

the room was lit by four bulbs and and the flash on a flash bracket. (Not that it really

matters)

 

My wife says I'm too picky. I guess most of the folks here would probably agree with her.

11 years of working with state highway engineers has apparently rubbed off on me. Please

pray for me!

 

BTW...here's one I heard: "State highway engineers are like slinkies. They're not much use

for anything. But, they sure put a smile on your face when you push them down a flight of

stairs." :)

 

Regards

[ron_buchanan]

maybe I'm missing something here, but you keep complaining about "ISO 800" and your ISO isn't really the issue here: 1-stop underexposed is 1-stop underexposed no matter where your ISO is set (the ISO will affect the particular aperture-shutter speed combo you'd be using to get that 1-stop underexposure, but you're still 1-stop underexposed.) It is possible that your meter is getting fooled and making the problem worse, but it's still not the fault of your ISO setting.

[marc s]

Hi Ron,

 

I'm certain you and Aaron are correct. It's definitely operator error and not the fault of the

gear.

 

It just seems that when I shot film I had brighter pitures in the same kind of atmosphere

even when I was down a stop. The again, maybe I did and just fixed it in the dark room.

 

That's what's great about the forum. Folks like you and the rest of the photonetters can

give me some insight and correction.

 

Regards

[bo_douglas]

What metering mode were you using? I would have to guess you were using matrix metering. I think your meter was trying to get the bright white of the piano keys and the music to be underexposed by about 1 stop, and the child ended up being more than one stop under exposed.

 

-Bo

[wedding-photography-denver]

Marc, I also wonder what you are using to meter? If you are incident metering and getting a negative 1 stop exposure, then you will need calibrate your meter to your camera. For instance, my Sekonic L508 reads about 1/3 stop less than my 5D's meter and about the same for the 30d's and 20d. I know when metering to make the mental adjustment and once you are familiar with its behavior, you will do the same I dare say.

 

If you are using the cameras meter, well then, all bets are off. For this I use almost exclusively the CWA and it seem to help with the flash exposure too (I don't know why this is so, but it does seem to be). I use flash for a fair amount of my work and don't like to have it be too obvious (most of the time), so when outdoors in sunlight I set the camera to AV if I'm on the fly with the CF set to enable the safety when in AV/TV. Then I generally set the flash to -1 or 2 stops (dial it down). Overall this works well enough unless there is direct sunlight behind the subjects, in which case you will often have to up the FEC to +1 or 2 to balance things, and even then it will sometimes give you much trouble. Test this for what you like.

 

On another note: Using 800+iso and underexposing is somewhat fatal to your shot. Why? because at higher ISO's there is more noise present to begin with, then adding underexposure to it only serves to pump up the amount of nasty noise. It is better (as I am sure Jammey Church will attest) to slightly over expose your shot and then pull the exposure down in PP for the purpose of noise control at least.

 

Hope some of this is somewhat helpful..?

Best, D.

[brandonhamilton]

Before you go any further, you really need to take a minute or a few hours and go read up on how exposure works. For some reason, you seem to think that the ISO film or digital setting you are using creates or causes brightness or lack there-of in an exposure, and that is completely wrong.

 

There are 4 things that affect or create your exposure, and they are

 

1.) how much light is available to be exposed

2.) your aperture

3.) your shutter speed

4.) your ISO setting/film choice

 

ISO by itself doesn't mean anything. For example, if you go from iso 100 to iso 800, (3 stops of light) but go from outside day light to dark indoors (6 stops? just guessing) then if all other settings remain the same, you are still going to be under-exposed by 3 stops. So not only do you adjust your ISO, but you also need to adjust your aperture and shutter speed, as well as do your best to boost the available light (i.e. flash).

 

The way I read your post, is that you think iso 800 will give you a "bright" or "light" picture no matter where you are or what other settings you are using.

 

"It's been a while since I shot film. However, I can't remember my film shots ever coming out so dark even with 400 speed film."

 

That says it all right there.

[merle_white]

Marc,

 

When you are comparing to film. Remember if your film is negative film you are having it processed and printed by a photo finisher and they will be making density corrections (within limits)

[aaron_lee___minneapolis__m]

Marc,

 

If you upped your ISO to 1600 with the same f/stop and shutter speed and took the same shot it would be "brighter", but the background would still be underexposed.

 

As someone else mentioned, underexposure is fatal on digital. Especially at high ISO because you have to push the image so far in post production that it just amplifies the noise. You are better off using a higher ISO (especially on Canon) and squeezing the most possible exposure you can into the image. Do a search for ISO 3200 by Jammey Church. He has some fabulous examples on high ISO exposure techniques.

 

Aaron Lee

[marc s]

Thanks for the answers.

 

Metering was done with the camera's metering in Evaluative. The fact that I have limited

understanding of my 580 EX didn't help matters.

 

However, I have spent the entire day studying and practicing with the flash including fill

flash, etc iin different ISO's. I've really learned quite a bit. In fact, a friend asked me to

shoot

some pictures of her this evening by the river. It was the perfect place and time to try out

what I learned from these postings. The stills really came out better than what I had

hoped. I'll try posting them tomorrow.

 

I'm not very good at posting in forums. Therefore, sorry for my confusing descriptions and

wording. However, I wasn't really expecting to get better stills by cranking up the ISO and

leaving the settings the same. I was just expecting a better overall brightness from such a

high ISO. Anyways, my question has been answered and I thank you kind folks for that.

 

Regards