Rebel Sl1 lots of noise at 100 ISO??

[Bricheez]

I recently got my rebel for Christmas and have been using it in a basic 101 class. My teacher and I have noticed that in my photos with low ISO, there is as much noise as with and ISO 1600. The lens and everything has been cleaned, I've done bracketing shots and all are the same, I'm not sure if it's an internal issue or not. Anyone having similar issue or can offer advice

[jrhoffman75]

There is a dark/light pattern in sky. I've seen similar when folks wet cleaned sensor and did a poor job. 

[ebiggs1]

The res is too low and pixelated for me to tell for sure.  You might be right.  It may be all the lens is capable of.  Sending it to Canon is the sure way to tell.

[Peter]

Take a new sample of the same sky and shoot in raw. Upload the file wherever you want. For example at filedropper.com.

I ask you for a raw file because it is hard to tell if the thingy at the sky is jpg compression or something because of sRGB.

For me it seems "normal" and has nothing to do with wet cleaning or broken things in the camera.

[ebiggs1]

"For me it seems "normal" and has nothing to do with wet cleaning or broken things in the camera."

I tend to agree. 

[Peter]

It is called posterization.

It is caused by the 8-bit JPG not having enough data to give you a smooth gradient when large blocks of color slowly change. You’ll often see it in the blue sky in landscapes, or as in this case, with large areas of color in the background.

Shoot in raw, edit in 16 bit tiff and in Photoshop, save for web. You will still be able to see, but much less of it.

[ebiggs1]