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Old Jun 21, 2009, 12:13 PM   #1
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Default Manual setting on the Canon DSLR Rebel XS - why slow shutter?

I am getting to know my camera and finding that TV mode is really great, but I think I should be shooting on Manual most of the time, right?
Here is the issue I am having - when I am shooting with Manual mode, it takes forever for the shutter to go, leaving a picture that is blurred and over-exposed. I have changed the ISO speed to the fastest, but that doesn't seem to help. I am new to this photography game, but I do have some experience with camcorders and such.
Any help would be great,
Thanks
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Old Jun 21, 2009, 12:55 PM   #2
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If you are using full manual then changing the ISO won't help at all, you need to change the shutter speed. In all honesty I rarely use full manual or even Tv but rather Av as this allows me to control the depth of field which is more often key then to ensure I'm getting a shutter speed as desired will play with the ISO. Times I use full manual are outdoor sports shooting where this not a lot of change in the lighting, indoor sports, flash photography indoors and studio work. I will use Tv when I need to bring the shutter speed down (Av is better for ensuring the highest shutter speed while getting a correct an exposure) such as motorsport to create motion blur and everything else is in Av.

So back to your question just change the shutter speed while in M, it should be the same as changing the shutter speed in Tv by rotating the main control dial between the shutter release and ISO button.

That's about it really.
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Old Jun 21, 2009, 3:20 PM   #3
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Thank you for that, I will give it a try. I was worried that the manual setting might have been broken because of the long shutter times.
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Old Jun 21, 2009, 3:21 PM   #4
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You're welcome. I think you are fine and just that the shutter is set slowly in that mode. Let us know how you get on.
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Old Jun 21, 2009, 7:01 PM   #5
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Ok, I have been looking through the manual and testing, but I can't seem to find a way of changing the shutter speed. I can change the aperture by using the spinner by the shutter button, but the shutter changes on it own...I have changed the Fstop to 1.8 for a darker room, but the shutter is alluding me...
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Old Jun 22, 2009, 2:38 AM   #6
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Are you definitely in M mode and not Av or P? When you are adjusting the setting do you get a correct exposure each time or is that changing with the different settings you are putting in?
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Old Jun 22, 2009, 1:06 PM   #7
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With most dSLR models that only have one control wheel, you just need to press and hold the +- button when spinning the control dial to set one versus the other (aperture or shutter speed when the control wheel is used).

IOW, press and hold the +- key and it will change the other setting when spinning the control dial when shooting in manual exposure mode.

With some cameras, you can set which one is preferred without any extra button press (so you can set the control dial to either shutter speed or aperture by default).

The +- button is the same button you'd normally press and hold so that the control wheel could be used to set Exposure Compensation when in other modes. For example, if shooting in Aperture Priority mode, the control dial would normally change Aperture on a camera with only one control wheel. By pressing and holding the +- key, the control dial is used for Exposure Compensation instead.

But, since you don't have any Exposure Compensation setting in Manual Exposure mode (your shutter speed and aperture settings take the place of it), pressing and holding the +- button is used to allow the control dial to toggle to the opposite setting (either shutter speed or aperture, depending on camera model and custom settings).
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Old Jun 22, 2009, 3:15 PM   #8
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I was in AV mode like you suggested, sorry I should have clarified that first - does this change things?
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Old Jun 22, 2009, 3:33 PM   #9
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If you're in Av (Aperture Value, a.k.a., Aperture Priority) mode, when you spin the control dial, you're changing the Aperture Value (expressed as f/stop).

When you vary the aperture, you're controlling the iris in the lens (which like a pupil in your eye, can be opened up to let in more light or closed down to let less light in).

When you use Av mode, you select the desired aperture. Then, the camera selects the correct shutter speed for proper exposure, based on how it's metering the scene.

If the camera is metering the scene where you end up with a darker or brighter exposure than desired, you can use Exposure Compensation (press and hold the +- button while spinning the control dial) to change it's behavior.

If you use a -EV setting (needle to the left of center), you'll have a darker exposure than the camera would have used. It gives you a darker exposure by using a faster shutter speed with the selected Aperture.

If you use a +EV setting (needle to the right of center), you'll have a brighter exposure than the camera would have used. It gives you a brighter exposure by using a slower shutter speed with the selected Aperture.

The selected Aperture impacts the shutter speeds you'll need for proper exposure. For example, an aperture setting of f/2.8 (if you're using a brighter lens with that aperture available) will allow you to use shutter speeds 4 times as fast as one as you could use at f/5.6 for a given lighting condition and ISO Speed. Aperture also impacts Depth of Field (wider apertures will allow for a shallower depth of field when desired to help subjects stand out from distracting backgrounds).

The aperture scale in one stop increments (with larger than f/1 apertures possible but very rare in lenses) goes f/1.0, f/1.4, f/2.0, f/2.8, f/4.0, f/5.6, f/8.0, f/11, f/16, f/22... With each one stop move to a smaller aperture (represented by higher f/stop numbers), you will need shutter speeds twice as long for proper exposure for the same lighting and ISO speed (only half the light gets through compared to a one stop larger aperture).

There are only 4 main variables involved for proper exposure. We've already discussed Aperture. The other variables are Lighting (typically measured in EV, which stands for Exposure Value), ISO speed and Shutter speed.

ISO speed is how sensitive the film or sensor is to light and is the same thing as the older ASA rating for film. The higher the ISO speed, the faster you can expose it (each time you double the ISO speed, you can use shutter speeds twice as fast for the same lighting and aperture.

Shutter Speed is how long the camera's shutter stays open to expose the film or sensor.

IOW, it all boils down to how much light you have, how sensitive the film or sensor is to light (which you control via the ISO speed), and how much light you need to let it see to "expose" the image (which you control via the aperture opening size and shutter speed). These exposure calculators and simulators may help you to understand it better:

http://www.robert-barrett.com/photo/...alculator.html

http://www.photonhead.com/simcam/shutteraperture.php
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Old Jun 22, 2009, 3:54 PM   #10
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Getting back to your issue (blurry photos)...

If you're getting blurry photos, your shutter speed is probably too slow.

If you're shooting in Aperture Priority mode, with the Aperture set to it's widest opening (smallest f/stop number), and you already have ISO speed set to it's highest value, and your shutter speed is still too slow, then you don't have enough light for the brightness of your lens.

Most kit lenses are too dim for use indoors without a flash with moving subjects (or, you'll get blurry photos, because the shutter speeds needed for proper exposure will be too slow).

Now, if you're getting photos that are too bright, that could be indicative of a metering problem where you need to use a -EV setting wtih Exposure Compensation to get a darker exposure (which will give you faster shutter speeds if shooting in Av mode). But, most kit lenses are not going to "cut it" indoors without a flash. So, your best bet is to use a flash instead.

I'd post a downsized sample for members to look at if you want help with a specific image, and make sure the EXIF is retained.

When I use Windows, I use the free Irfanview for downsizing images (but, most image editors can resize if you're using something else).

With this software, after you open an image, select "Image>Resize/Resample" and make the width around 640 to 800 pixels wide for posting. Leave the Preserve Aspect Ratio box checked. After you click OK, use the "File>Save As" menu choice, select jpeg as the file type, and give it a new filename. I'd set the Quality slider you see come up at around 80% to keep the file size within limits. Leave the retain EXIF box checked (so members can see the camera settings you used), and attach the photo to a post here.

Then, members can look at the photo and give you some tips on what you can change for better results.


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