Lens advice please?

Try wrapping a rubber band around the lens cap to improve your grip.

The EOS 50d Mark II is what's known as a "full-frame" camera. Its image sensor is the same size as a frame of 35mm film. The Sigma DC lens is intended for cameras with smaller sensors. The lens is compatible in that it will work with the camera to take pictures, but the pictures are cropped due to the smaller imaging area of the lens.

In order to use the full image sensor area you need to use full-frame lenses. In the case of Sigma, this means lenses without the DC designation.

Google the words "disassemble a digital camera" for some good advice and pictures of how to do it.

As long as you donot make any scratch on the lens there is no problem. But I would advice you not to try out on delicate parts like lens of your camera. You can consult your Canon service centre. Generally lens cleaning solutions are available, you can use them, you can refer your camera manual. I have once used a slightly wet cotton, and my camera Canon SX110 is working fine without any issue. But better to take advice of Canon service centre.

The FEE error means that the lens aperture ring is not set to the smallest opening (highest number). The camera body needs it set this way so it has full control of the light reaching the film (or sensor). The lens has a lock mechanism to keep the aperture ring at the smallest opening so you don't accidentally move it when using or changing the lens. On older Nikon lenses, it's a little round button with a white arrow which you push down and rotate to match the arrow with an orange mark. On newer Nikon lenses it is a little slider with a white dot which you can move with your fingernail to match the white with the orange mark.

Solved

Trouble shooting Error 99

1. Solution: Remove and replace the battery.

Power the camera off

1. Remove the battery.
2. Wait 15 seconds.
3. Replace the battery.
4. Power the camera on.

2. Clean the lens contacts.

Clean the lens contects on the rear portion of the lens with a clean pencil eraser.

• Mount the lens on the camera.
  
• Take a picture.
  

If the error persists, the camera and/or lens may need be serviced by a qualified Canon Service Technician.


3. Remove the 3rd party accessory.
Please remove the 3rd party accessory and replace it with genuine Canon Accessory.


4. Solution: Remove third party lens and try with Canon EF or EF-S lens.
Remove third party lens and try with Canon EF or EF-S lens This link will bring you to the camera page on Canon's website: More trouble shooting, drivers and downloads http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&tabact=SupportDetailTabAct&fcategoryid=215&modelid=11154#DownloadDetailAct Best of luck. Could you please rate this advice. Thanks so much!

reset camera by removing battery completely for about 10 seconds.
otherwise, time for service.
sounds like a processor board issue.
you can use a contact cleaner sparingly, available from frys electronics or any other electronic reseller like radio shack.
good luck
mark

what do you mean dark? if they are underexposed... extend you exposure time.

There is a small round button near the shutter release... hold that down, and rotate that thumb wheel thingy. You can over or underexpose your camera's auto metering by 2 stops in 1/2 stop increments...

After that, you should learn how to take control of the camera and shoot in manual mode. It give you the ultime power

The built-in Speedlight on many Nikon cameras is designed to be a convenient way to either light up a dark subject or to add fill light to a daytime scene. The built-in Speedlight cannot replace a full size, external speedlight which should be used when more power or coverage are needed. Because the built-in Speedlight is compact and close to the camera it cannot be used under all conditions. When using a lens that is physically very long, a subject that is very close, or a wide lens hood it is possible that a shadow may be cast upon the subject. Notice, in the sample below, the round shadow in the bottom center of the photo. When the lens is too long or the coverage is too wide with a close subject a shadow of the lens itself is cast. In figure "A" below the lens is casting a shadow. Switching (or zooming) to a shorter lens (figure "B") prevents the shadow and allows even illumination. If your lens, subject, or lens hood choice create a shadow, an external flash (either on the camera's hot-shoe or connected to the camera by a wire or wirelessly) should be used to fully light the subject.