Birds: 450d+55-250 (not so good)

Started Dec 9, 2012 | Discussions thread
Shop cameras & lenses ▾
R2D2 Forum Pro • Posts: 16,928
Regarding 100% crops...

AnthonyL wrote: I just made the mistake of paying close attention to what you posted

LOL.  Sorry for getting back to you so late.  I had slideshow images to prepare for our camera club meeting last night (took several nights of work).

AnthonyL wrote: a 100% crop means to crop the WHOLE picture - doesn't it! Basic logic.

Well close.  The term "100% Crop" actually means "100% Pixel Dimensions," and not necessarily 100% of the original image (or "whole picture").

Note: 100% Pixel Dimensions simply means that the image (no matter how big) is not resized in any way.

So a 100% crop could indeed be the entire original image (which on a monitor could be several feet wide), or it could also refer to a small portion of the image which has been cropped from the original (and not resized).  For instance your Cedar Waxwing is an example of a 100% crop, even though it isn't the entire ("whole") image.

The fact that you cropped so deeply into the original image (even though you didn't resize) is part of what caused the very low image quality.  As I recommended earlier, for best image quality, avoid cropping more than 50%.  Meaning don't crop away more than half of your pixels (as Olga pointed out).

Note: Now I've seen some folks use the term "50% Crop" to mean "50% Resolution."  Which of course would mean you are throwing out a whopping 75% of your pixels.  And unless you have a LOT of megapixels to play with, I wouldn't recommend cropping that far into an image (unless it's just for posting to the Web).

Anyhow, apart from this momentary confusion as I said in response to your post I don't as a rule resize.

If you follow my guidelines above regarding cropping, you Will  have to resize for posting to the Web (or else your images will be too large for the screen).  Having to resize for the Web is a good thing actually, and your images will start to look much better, especially if you don't crop more than 50%.

logic tells me that resizing, either up or down, must lose detail

Precisely.  When you are printing, never ever Resample when you resize/crop your image.  You'll maintain the most detail that way.

Even better yet, you'll get even more detail when you shoot in good light and fill the frame as much as possible.  You'll then have to resize/resample your images for posting here on the Web, but as I explained above, that is a Good thing.

Best of luck!


-- hide signature --

Good judgment comes from experience.
Experience comes from bad judgment.

 R2D2's gear list:R2D2's gear list
Sony RX100 II Canon EOS 70D Canon EOS M5
Post (hide subjects) Posted by
(unknown member)
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow