Rebel Xti Shutter & Aperture..help please!

[usman_arshad]

Hi I am new to photo.net i had a few questions on the new camera i bought the

rebel xti. is it possible to manually adjust the shutter speed and the aperture

at the same time?

 

next question is that i would like to take a picture at night where i can have

streaks of car headlights and brake lights in the middle of a busy highway but

still would like the landscape and buildings in the background vivid. i know i

can do that with slowing down my sutter speed in Tv mode. but also i would like

to have my aperture open enough to get enough light in to get the buildings in

the photo. does exposure help here? any suggestions, comments, help would be

greatly appreciated.

 

last but not least. the M mode. is it mainly for manual focus. or can auto

focus be used. same with the P mode. just had questions of what can be done in

these modes. sorry for bombarding with a lot of questions. just new to DSLR

world and dont have a book for my camera. BTW the lens i own is a sigma 28-70 f

2.8-4.

 

please help

[phule]

<<is it possible to manually adjust the shutter speed and the aperture at the same time?>>

 

Of course it is. That would be what M(anual) mode is for.

 

<<next question>>

 

Use a tripod and take lots of pictures.

 

<<is it mainly for manual focus. or can auto focus be used>>

 

M mode has nothing to do with focus, manual or otherwise.

[shambrick007]

The manual is your friend.

[sdsalyer]

You can download the manual for the Rebel XTi at the following URL:

<p />

<a href="http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&tabact=DownloadDetailTabAct&fcategoryid=314&modelid=14256">http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&tabact=DownloadDetailTabAct&fcategoryid=314&modelid=14256</a>

[samuel_hon]

Hi there

 

Dont bother with the P mode. M, TV or AV are more fun and give you more control

 

If you want to take long exposures, use the timer or a remote to trigger to reduce shake. If in town, I like to use bulb mode (you'll find it when changing the exposure in manual mode) and use some black card/felt to cover the lens when you've got something non-picturesque in front (I live in London and there are lots of double-decker buses which I dont like in my streaky photos)

 

Good luck

 

Sam

[zigzag]

1. Manual mode = adjust shutter speed and aperture together<br>

2. For night streaks you need long time exposures and a tripod. Using the timer means you don't have to press the shutter (and shake the camera) when you want to start. Try speed settings from about 1/15s to 20s and see the difference (use the Tv mode or manual M mode). Look carefully at your exposures. Use a low ISO (100)<br>

3. Manual mode is for manual control over aperture and shutter.<br>

4. RTFM<br>

[jeff_higdon]

Usman: All of the above advice is excellent especially the RTFM. Whenever you want that effect, a wired cable (Canon Remote Switch RS-60E3 - about $26 at B&H) and a tripod are your best friends. I find the wired cable a little more helpful to get sharp images. Works well with the long exposures (10 seconds each for the attached photos) or the bulb setting. When using the bulb setting and the cable release, you can keep the shutter open as long as you want by holding down the button on the release. Experiment from a few seconds up to maybe 30 seconds. The above advice also works for taking pictures of fireworks. The photos attached hereto show what the cheap kit lens (18-55) and the Xti can do. They were both taken at the same fireworks show and I think my settings were 55mm, f11, 200ISO and the 10 sec shutter on both of them.<div></div>

[usman_arshad]

thank you everybody for your answers. it really helped.

 

'RTFM' LOL glen i would if i had one but thnks to spencer i can download one now.

 

great shots jeff

 

thanks for the tips rob and samuel

[arie_vandervelden1]

As pointed out, M on your camera is manual shutter+aperture. Adjust the shutterspeed with the wheel. If you flip fast 30 s you get bulb exposure - use a remote switch. Adjust the aperture with the wheel while holding the +/- button.

 

For time exposures in dim light I suggest flipping the lens to manual focus, and setting the focus manually to infinity or something close to infinity, or the hyperfocal distance if you want to be precise. This avoids autofocus-hunting when there's nothing for the AF to snap onto.

 

Shoot some test frames, look at the histogram, and adjust your exposure.

 

If you want to get fancy you can try dark-frame subtraction. This reduces noise. Note that this locks up the camera for a time period equal to your shutterspeed.

 

Have fun.