Why can't I fine select my ISO on the Canon 650D (T4i) like it does in auto?

I recently bought the Canon 650D and when I take a picture in Auto it will give me an ISO of lets say for example 450 or 520 but when in manual and I go to change my ISO I only get the options of 100, 200, 400, 800, 1600, 3200, 6400 and 12800, why is this why can;t I fine tune it like the auto mode can?

Also when I bought this camera the woman in the shop said that the Canon was way better than the Nikon D5100 so I bought it over that but I honestly think the D5100 looks like it has better image quality. I told her I don't care about video and she said it takes better still so I went for it, but if this is wrong I will take it back and ask for the Nikon D5100 if they allow me?

You can adjust the ISO settings in the camera menu. You should be able to set it for full stops, half stops, or 1/3 stops.

The lady in the store was absolutely wrong. The Nikon is not better, nor is the Canon. They are so much alike that the only difference is the name on the outside.

Image quality is so close to identical that you can't possibly tell the difference. You would find that the Nikon images will look exactly like the Canon images. It is your skill with the camera that makes the difference, not the name on the outside. If you can't get a good photo with the Canon, changing brands isn't going to make any difference.

I don't own this camera, but let me tell you what I do know. Not all dSLRs will let you select ISO in partial stops. My very first dSLR was an entry level model just like this one. It was the Sony A100 dSLR. In auto mode, the camera would at times choose ISO values like 160. But when I chose the ISO, I could only choose in full stops like 100, 200, 400, 800.

So it is possible that you won't have access to those other ISO settings. I have a Nokia N9 cell phone that is the same way. In auto mode it has lots of odd ISO numbers like 500, 520 etc, but if I choose the ISO it's full stops only.

Next up, the person at the shop was dead wrong about the Canon being better. The image sensor, the heart of any camera is better in the Nikon 5100 in every way. You might not see a difference between the two in good light, but in low light at high ISO and when shooting high contrast scenes (especially when you shoot RAW) the Nikon will beat the Canon no problem.

That doesn't make the camera better, but in my mind image quality is KING and comes before all the other features, some photographers might feel differently though.

As far as returns go, just check with the store policy, or check the receipt for return conditions. Some stores will only refund a portion and charge a restock fee because they can't resell the camera as new and they take a loss at that point.

Search through the menu options and consult the manual. I'm sure there's the option to "fine tune" the ISO to half or third stops. But in the old days of film, we only had the options of 100, 200, 400 etc!

Personally, I think Canon and Nikon are the world's leading brands and perform equally as well as each other. You didn't do wrong in going for the Canon; I would have done the same.