350D vs 450D Puzzle

[ccronje]

Hi All,

I'm fairly new to photography and very new to this forum, so please excuse me if this question is posted in the wrong place. I was wondering if anyone can help me explain this.

I just purchased a brand new Canon 450D and I noticed something tonight that has got me baffled. My wife has a 350D and I decided to take some comparitive photos to compare the 2 cameras. I took a photo of some flowers with the 450D and a 50mm f/1.8 lens, then I moved the lens to the 350D and took the exact same foto. Every time I focused on the exact same spot (one of the white flowers in the front), I stood in the exact same place etc.

To my surprise the photos that I took with the 350D was consistently much better than the ones I took with the 450D. If you look at the pink+white flower in the 2 samples below you can see what I mean..the 350D's photos has more detail and it's much sharper. The 450D photo seems almost out of focus. I tried various settings, but just could not get the same quality image with the 450D. The two photos below were taken in Program AE mode.

If anyone has any ideas on why there is such a difference between the 2 cameras it would be much appreciated.

Thanks

Chris

To better see the difference, the original photos with can be seen here:

350D Original
450D Original

350D

F-Stop: f/1.8
Exposure Time: 1/200
ISO: 400

450D

F-Stop: f/1.8
Exposure Time: 1/125
ISO: 400

 

[fokker]

Something must have changed since the shutter speed is lower on the 450d shot. It is possible that due to metering differences the exposure is slightly different, and the slower shutter speed of the 450d may be causing a slight amount of camera shake (assuming you weren't using aa tripod).

Probably though the main thing I would check is the picture styles settings on both caemras. Assuming you shot these in jpeg, it looks like the 350d one has the contrast and sharpness bumped up, as well as more details in the white flowers due to less exposure.

If you really want to do a proper test you will have to use a tripod and not move it between switching bodies, and ideally don't touch the focus on the lens between shots. You need to set both picture styles to be the same (just use neutral or something simialr) and shoot in manual with the same settings.

 

[Derrel]

Focus also appears slightly different, and at f/1.8 at that close range, the depth of field is very sketchy. In the 450D shot, it looks like the focus is misplaced just a bit for the majority of the scene. Why the exposure program selected flash and f/1.8 at that focal length and that focus distance is somewhat perplexing--that's actually kind of a lousy exposure combo in both shots. An aperture of f/4 would have been safer,and better.

The picture style or image processing parameters do appear a slight bit better in the 350D shot. Not by a whole lot, but it is noticeable.

 

[ccronje]

Thanks for the quick replies everyone.

I honestly can't explain the different compositions..both cameras have only the centre focus point enabled and I was sure I focused on the exact same flower every time.. being the beginner that I am, I didn't even notice the difference in composition. But that's not all..I also noticed that both cameras were on aperture priority and the f/stop was set at f/1.8 on both, not program AE as I stated. Sorry about the incorrect information.

Anyway, I quickly put the 450D in Program AE mode and on a tripod and used the timer to take the shot. The program AE selected f/4.0 and a shutter speed of 1/60 and this time the photo looks a lot more in focus (see below). I did actually test it with the tripod while it was on f/1.8 and it looked similar to the images I posted earlier, so the tripod alone is not the thing that made the difference.

Thanks again for your advice.

Chris

Click here for the original