Cropping an image too much

[Tommy Rodgers]

I often see the comment that a hugh crop generally creates poor image quality. I do not doubt that wisdom, but I do not know why. Will someone please explain or point me to a place to get there answer.

Thanks,

[arash_hazeghi]

It's pretty simple Tommy, A digital photo consists of pixels, information or "detail" is recorded in each pixel, when you don't have enough pixels you don't have enough detail and the photo will suck :w3

This should serve as a good example :

http://www.birdphotographers.net/forums/showthread.php/83879-5000-Pixels-of-Barred-Owl?p=669137&posted=1#post669137

[George Wilson]

I have had people ask me the same question and the simplest way I can explain it is as follows:

In a 10 Megapixel Image the dimensions are approx 3872 x 2592 give or take a few pixels. If you do the math, you will see that the long multipled by the short side is about 10 Million - hence 10 Megapixel. This format is 8" x 12" when printed.

Now, crop that image down to, say, 2422 x 1872 and using the same math process, you have created a 4.5 Mega Pixel Image. Printing this at the same 8x12 as the image above forces the pixels to be farther apart from one another.

This results in muting of colors, loss of sharpness and pixelation in your image. A good rule of thumb is to keep cropping to a minimum.

Remember this, the larger the negative or, in today's language, the digital file, the larger a quality enlargement it will yield. This is why you see landscape photographers using 8x10 view cameras for example.


Hope this helped

[Tommy Rodgers]

Thanks George. I think I got it. Appreciate the help

Best regards,

[Roger Clark]

Remember this, the larger the negative or, in today's language, the digital file, the larger a quality enlargement it will yield. This is why you see landscape photographers using 8x10 view cameras for example.


As someone who owns an 8x10 and multiple 4x5 view cameras and lots of sheet film in the freezer, I'll have to say I haven't used them in years. Now I take digital mosaics, usually surpassing what I could do with 4x5, and sometimes even 8x10.:w3

Back to the original post, I have a 50% crop from a 6 megapixel camera published in Natures best (2004), printed full page. That is a 3-megapixel image. But I sure wish I had a 20+ megapixel camera at the time! It would have been a much better image. So subject is more important than enough pixels for sharpness. But it is better to have both (lots of pixels and sharpness, unless it is an intended blur of course).

Here is the Natures Best image if you are interested:
http://www.clarkvision.com/galleries/gallery.bird/web/c01.14.2003.img_5113.egret-flight.f-600.html

Often photographers get obsessed with sharpness. A sharp image of a boring subject is just a sharp image of a boring subject. The subject, the light and composition are more important in my opinion than pixels limiting sharpness.

Roger