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reddawn
17th of April 2001 (Tue), 12:31
Hi

I've quite a few questions about exposures which I would like to ask the experts here.....

1) What does the exposure compensation REALLY do? My guess is that by toggling the exposure compensation, we are really asking the camera to change the aperture size fstops or the shutter speed (or both) to gain the desired exposure. (since without the ability of the camera to select ISO speeds in the AE modes, these are the 2 main determinants of exposure)
Am I correct in my assumption, even though the EXIF info does not reflect the changed values of aperture size and shutter speed, instead displaying the exposure compensation separately, with its own unit of measurement....

2) Exposing correctly for both bright AND dark subjects is a problem for me. For example, I have this scene of a statue that is brightly illuminated with floodlights at the base. I wanted to take a picture of this statue at night, composing it in such a way as to include the surrounding building and a bridge.

However, the building and bridge are poorly lit compared to the statue. When I expose for the building and bridge to bring out the details, the statue gets overexposed and burnt out; when I expose correctly for the statue, I can hardly see the bridge. Spot metering doesn't work here (how to judge a middle tone at night?) and it's always either the statue gets overexposed, or the bridge gets underexposed.

What do you pple do in such situations?? I know the trick to do a double exposure and then overlay the images in photoshop, but is that really the ONLY way to get a nice picture?? Is there really no way to "get it right" when you take the picture? How do traditional film cameras manage such situations?

I seem to encounter such situations very often. Maybe I need to rethink my composition?

3) I am having some difficulty achieving shallow depth of field for protrait shots like those I've seen in traditional film photography. I know the basics
- zooming in to increase focal length
- using macro mode if possible
- selective focus by manual focusing
- throwing the aperture wide open (frankly speaking, I can hardly tell the difference using this oft-quoted method!)

Are there any other tricks? (other than Photoshop)

4) Since day 1, I have started using the G1's full manual mode to take pictures (even though I was a complete newbie to photography). What I did was to toggle the aperture and shutter speeds until the image "appears right" in the LCD. There are only 2 variables to worry about with this method, and it seems easier, rather than having to worry about compensation, spot metering etc etc....

Since in manual mode, spot metering, exposure and flash compensation are disabled, does it really mean that we can achieve the same quality and desired effect by just controlling the aperture and shutter speeds? Does it mean, as long as you're in full manual mode, you don't miss out on anything? (ie you don't need the metering modes at all) My guess is again yes, if one is experienced enough to "judge the light". Is that a right assumption? In the absence of a LCD, how does one judge with a 35 mm film camera? Even with on-board metering, how does one compensate with the 35 mm film camera without instant image feedback?

Is there a proper workflow for exposing shots with a G1? like a blow by blow account of how to perform exposure with a G1?

Lastly, thanks for reading so far :)
hope I haven't bored anyone here with my questions ;P

Pekka
17th of April 2001 (Tue), 13:36
Good questions. Not so easy to answer.

1) What does the exposure compensation REALLY do?
I simply adjusts shutter speed in Av mode and aperture in Tv mode. In P and Auto it adjusts shutter speed. Correct me if I'm wrong (no time to test it).

2) Exposing correctly for both bright AND dark subjects is a problem for me.
Yes it is something you have to decide. Or use fill-in flash. It's either, unless you camera has incredible dynamic range. With G1 you'd better expose so that bright areas go never over, as you can raise levels in PS a lot without too much damage. See http://www.botzilla.com/photo/G1expose.html

And yes, I do prefer selecting what to shoot so that the frames relative brightness areas are close to each other, especially in night (evening) shots. This way you let the camera work as well as it can and not choke it. Pitch black night is not my preffered time for photography - near sunset is the best, at least here in Finland.

3) I am having some difficulty achieving shallow depth of field for protrait shots like those I've seen in traditional film photography. I know the basics
- zooming in to increase focal length
- using macro mode if possible
- selective focus by manual focusing

Are there any other tricks? (other than Photoshop)
A tele lens (B-300 or the Canon one) helps some.

throwing the aperture wide open (frankly speaking, I can hardly tell the difference using this oft-quoted method!)
Yep. It's one of the main reasons I'm on a quest for getting a D30. Real DoF (or even more closer to real) is very preferable. It makes subject separation more simple and a shallow DoF's forces you to think composing more which is a good thing.

Since in manual mode, spot metering, exposure and flash compensation are disabled, does it really mean that we can achieve the same quality and desired effect by just controlling the aperture and shutter speeds? Does it mean, as long as you're in full manual mode, you don't miss out on anything? (ie you don't need the metering modes at all) My guess is again yes, if one is experienced enough to "judge the light". Is that a right assumption? In the absence of a LCD, how does one judge with a 35 mm film camera? Even with on-board metering, how does one compensate with the 35 mm film camera without instant image feedback?
Manual mode is very "steady". There is no "trick" G1 does to adjust exposure in other modes, you can do it all in manual mode. Three variables: Speed, Aperture and ISO.

With film cameras people usually trust the metering indicators they see in the viewfinder. And new SLR's are very accurate in metering - more than any digital camera. It seems that manufacturers want to reserve some normal decent camera features for future models and when image quality competition is no longer in.

Is there a proper workflow for exposing shots with a G1? like a blow by blow account of how to perform exposure with a G1?
In M mode I can see the exposure very well in LCD, and also dynamic "over": watch the LCD in ca. 45-60 degree angle (from "downwards" ) and adjust exposure. You'll see CA (magenta) band on the edges when dynamic range is exceeded. You don't see this when viewing the LCD straight ahead. You'll also see color saturation changes easily.

In M mode if you put f to 2.0 and adjust speed downwards you'll see a point where it does not get brighter any more - there's a good reference point which should be remembered when adjusting aperture up and speed down.

LCD tricks you a bit: indoors you can expose normally with it, but outdoors image should be seen as a little brighter, and in dark a bit darker. Not much, but you should think of it a bit.

For "easier" shots and flash work I use Tv mode. I haven't used any other modes for some time now.

Pekka
http://studio-on-the.net/photography/G1/

reddawn
19th of April 2001 (Thu), 20:41
Hi

thanks Pekka for your informative answers.....

Red Dawn