Some basic questions I haven't come across

[Archer]

1. What does 100% crop mean (you take a 100% away you got nothing, right?)

2. I have a 6mp camera. If I crop half the image away do I now have a 3mp image? I suspect that's a stupid question.

3. If I had a 12mp camera and cropped half of it away, would the image be the same quality as a 6mp that had not been cropped? Does that make sense?

I like wildlife. I realize it's about getting close but my 18-55 wasn't cutting it. I picked up a 55-300 and, while much better, was surprised at how close I still need to be to get a good image without cropping the heck out of it.

 

[Overread]

1) A 100% crop is a term used to describe a crop of a photo when its sized at 100%. This is a method used so that you can show (online) the 100% quality of a photo, without having to upload the whole photo to the net (since most uploading sites limit you to 1000pixels or there arounds in upload size unless you are paying for the service).
So you could show a 100% crop of a key sharp point, for example, to show the overall quality at that point.

2) Actually I'm not 100% sure on that one - certainly you'll have the same image size as from a 3mp camera - though I'm not sure if the actual quality would equal a 3mp camera (since it can vary from sensor to sensor even if the mp rating is the same).

3) As said above not quite, the quailty might be near to but it will depend on specific camera models being compared.


Wildlife is one of the few areas of photography where not only is the equipment often expensive to get good quality; but also where one needs to have two skills, those of stalking and those of camera usage.

 

[o hey tyler]

1. What does 100% crop mean (you take a 100% away you got nothing, right?)

No, what a 100% crop is taking a sample of the image that is very small, but fully "zoomed" in so that detail can be seen. You're cropping the full size image to like a 300x300 square of just a small portion to gauge sharpness, clarity, focus, etc.

2. I have a 6mp camera. If I crop half the image away do I now have a 3mp image? I suspect that's a stupid question.

Yes.

3. If I had a 12mp camera and cropped half of it away, would the image be the same quality as a 6mp that had not been cropped? Does that make sense?

Most likely not. It depends on a number of things though. Which size you intend to display them, the ISO used, the overall sharpness of the image. I've cropped a considerable amount off of a 12MP image, and it displays fine for web view. Printing would be a different story though.

I like wildlife. I realize it's about getting close but my 18-55 wasn't cutting it. I picked up a 55-300 and, while much better, was surprised at how close I still need to be to get a good image without cropping the heck out of it.

.

 

[Rephargotohp]

OK, so say the original resolution you shoot will Print a 12 x 18" @ 300PPI Print You now crop an area 4 x 6" @ 300ppi, That 4 x 6 print will look just like that same area in the 12 x 18 print.
Now you take that 4 x 6" @ 300PPI file and you print at 12 x 18, You now have 1/2 the resolution print.

Which still may be acceptable because it is 150PPI,

now you do a 20 X 30 Print, You'll see a bad print

Depending on how big you intend print, thsi may be an OK way to do things, If you plan on printing bigger, you may want to think about a teleconverter and keeping your file at full resolution ( If you can't afford a longer lens)

 

[KmH]

A 100% crop means 1 image pixel is equal to 1 computer display pixel. The trouble is, not all computer displays display the same size pixels.
My main computer display is set to display 1600 x 1200 pixels.

The image sensor's megapixels is the native resolution. A 3000 x 2000 pixel image resolution is a 6 MP camera - 3000 x 2000 = 6,000,000. If you crop away 1/2 the pixels it is now a 3 MP image.

No because the pixels are now bigger and there are only half as many of them.

Cropping is something best avoided, because it entials discarding pixels, and pixels are resolution. Less resolution = less quality.

A 12 MP image. Then the same image cropped to 6 MP. Then the same image RESAMPLED to only 6 MP.

6 MP crop. Notice the field of view is smaller, magnifying the image.

Resampled from 12 MP to 6 MP:

 

[Archer]

Thanks all - very helpful

 

[Trever1t]

man that is one nasty critter.

 

[KmH]

He lives here: State Historical Society of Iowa

I am a part-time docent for the historical society during the summer months when the shop is open to the public.