What lens do I need to take an ';all crystal clear'; image with my Rebel Xti?

I have a sigma 70mm F2.8 EX DG lense and a canon lense that came with the camera. I am in love with ';all clear images'; of people or places but I just don't seem to either know how to use my camera or have the right lense.





Please help!What lens do I need to take an ';all crystal clear'; image with my Rebel Xti?
Try the A-Dep. mode. That stands for Automatic Depth of field, or everything is in focus that it can manage.





Select ISO 100 for sunglasses weather


200 for you dont have to squint but your not inside weather


400 for when indoors


800 for getting dark


and 1600 for really dark


800 and 1600 get noisy images though, so avoid them if you can.What lens do I need to take an ';all crystal clear'; image with my Rebel Xti?
http://www.photozone.de/4Technique/compo鈥?/a>





read that its great to learn depth of feild
For maximum Depth of Field (DOF) you really need a wide-angle lens used at an f-stop of f8 or f11. A 70mm lens with a ';crop factor'; of 1.5 on your camera is equivalent to a 105mm lens on a 35mm film camera. That is a perfect lens for portraiture. It isn't such a good lens for landscapes though.





A 16mm lens on your camera would be equivalent to a 24mm lens on a 35mm camera - perfect for landscapes. At f8 or f11 your DOF will be from the closest object in focus to infinity. NOTE: Be very aware of how close you can focus with any lens. If your lens can focus to within, say, 12';, then as long as you are 18'; away from the closest object you'll be fine.





IMO, you need to READ %26amp; STUDY the Owner's Manual for your camera so you can learn how to really use it.





These books might also be of help:





';Hands-On Digital Photography'; by George Schaub





';How Digital Photography Works, Second Edition'; by Ron White





These books were reviewed in the Dec. 2007 issue of Shutterbug Magazine. You can read them on-line at shutterbug.com.
The sigma should be a good start. Im not really sure what you mean by all clear but if you mean a picture where everything is in focus then try increasing the aperture. Something around f8 or f11 should give you a pretty wide depth of field. When you shoot at f2.8 the depth of field is quite narrow and will lead to a lot of foreground and background blurring which is not a bad thing sometimes.
The 70mm Lens SHOULD Give You What You're Looking For BUT, You Will Need To 'Stop-Down' The Lens To About f8 or f11 And Make Sure The Lens Is 'Focused' At 6 to 8 Ft From The Camera.





If This Isn't Working, Try Different Set-Ups. Placing Several 'Objects' At Various Distances From The Camera Until You Get 'Maximum' Depth-Of-Field.





Good-Luck!