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Photography Forums => The Canon EOS Forum => Topic started by: Halfpress on January 03, 2009, 09:41:43 AM



Title: Strange observation with my new 50D.......
Post by: Halfpress on January 03, 2009, 09:41:43 AM
I stepped up from a 30d,and always when viewing raw images in DPP,when I would click on 100%,it would be blurred for a few seconds,then res in pretty sharp.
With the 50D,when doing the same thing,it takes longer to res in,of course,but it lacks the sharpness of the 30d's image when viewed at 100%.
I'm not imagining it. When I view an sraw1 [similar size of a 30d file] at 100%,it seems to have the sharpness of the 30d image when it snaps in to res. Same goes for a sraw2 file.
Why would the 15mp file not be as sharp when viewed at 100% as the smaller ones,or the 30d's?????
This is frustrating because part of my upgrade was to be able to crop deeper. If the sharpness isn't there,what's the point???
BTW,when viewing a full size raw at 50% in DPP,it looks fabulous-way better than the 30d.
My lenses are 70-200 2.8IS,17-40F4L,300mm 2.8IS-so I know my lenses are up to snuff.
I can't return the camera because I need the high ISO perf. for BB games indoors,but I would appreciate it if Bob or anyone else could explain this to me.
Thank you!


Title: Re: Strange observation with my new 50D.......
Post by: Bob Atkins on January 03, 2009, 01:08:26 PM
A 100% view of an image from the 50D represents a section of a much larger image than a 100% view of an image from a 30D.

Let's say (to make the math easier!) the your sceen was 12" wide and had 1000 pixels. Let's say the 30D image was 3000 pixels wide and the 50D image was 4000 pixels wide.

At 100% the 30D image would be like looking at a section of a print which was 36" wide, while the 50D image would be like looking at a section of an image that was 48" wide.

The true test would be to make a 20x30" print from each image and look at that!


Title: Re: Strange observation with my new 50D.......
Post by: lukeap69 on January 04, 2009, 03:19:29 AM
Does this mean Bob that the main advantage of more pixels is more details?


Title: Re: Strange observation with my new 50D.......
Post by: Bob Atkins on January 04, 2009, 10:42:29 AM
That's correct. To a first approximation, the more pixels you have in a given area, the finer the detail you can resolve. Of course it depends on the lens too, since you can only resolve details that the lens can resolve and high quality lenses can resolve more detail than low quality lenses.


Title: Re: Strange observation with my new 50D.......
Post by: Halfpress on January 04, 2009, 07:57:27 PM
Thanks for repiles.
Was out today shooting ice covered subjects and 50d hunted once in a while. Is this normal when trying to lock onto a shiny ice covered object?


Title: Re: Strange observation with my new 50D.......
Post by: Bob Atkins on January 04, 2009, 08:09:58 PM
If the feature you are focusing on has low contrast, then AF is more difficult and you can sometimes get "hunting" for focus. Unless you see frequent AF problems, an occasional searching for focus isn't something to worry about too much.

AfF s typically best when using a fast lens (f2.8 or faster) and the center focus zone is manually selected.