When to Crop

Anouilh

This is such a vast subject.

Cropping and enlarging are one way of finding out more about the quality of the original photo. I'm not pleased with this crop, but it's somewhere to start.

Calina

Anouilh,

I am unable to make a call on whether this is a good crop or not without seeing the original image.

If you are looking for advice on it, you really need to give the community something to work with.

I would also add that I don't understand "cropping and enlarging are one way of finding out more about the quality of the photograph". A lot of us use cropping to enhance the composition of the photograph, not as a QC measure. Enlarging I would endeavour to use as little as possible even though I have blown up two or three images to 2 or 3 metres across, very successfully.

Paulw

Anouilh wrote: »

Cropping and enlarging are one way of finding out more about the quality of the original photo.

I actually find that zoom works better to find out the quality of the image. Just set your zoom to 100% or greater and you will see any quality or defects in your image.

As for cropping, it's generally used to re-focus attention within the image, and to remove distractions.

Enlarging? Thankfully, I've never had to do this. The images are quality enough to print poster size without need for enlarging.

sNarah

Never enlarged photo's, as cropping go, use it for:

- Cutting out a stupid thing like a latern pole or something that I didn't notice when taking the photo.

- Enhancing portraits or close-up photos to bring out the subject better.

- To provide a better composition, mostly depending on personal taste that is.

I don't think there's any 'rules' about when to or not to crop, it's more of a personal way of looking at your photos and thinking about how you can improve them, by all means necessary, including cropping out bits that you don't like.

I do always make sure I keep the original to go back to later on if I change my mind about it :-)

AnCatDubh

A crop will take unnecessarry distraction out of a composition to generally improve on that composition. I think commonly people can be over zealous with their crop and end up cropping too tight which means that you lose all sense of context of your composition or to the other extreme of not cropping enough and the composition remains 'busy' with lots of distractions. I think it differs for portrait as opposed to landscape, as opposed to streetscapes, etc., etc..

I know you said you weren't pleased with the one posted and i'd have to concur - I don't think it contributes to the composition but as calina said we don't have the original to go on so it can be difficult to tell.

oshead

I agree with you Anouilh. Its not a very effective crop. Ideally you should try to get composition right at exposure time. If you do feel the need to crop any image, IMO you should try to not crop too much.

Tightly cropping an image to check quality is tantamount to pixel peeping which, can be a very bad habit to get into.

Dave OS

AnimalRights

I would do what PaulW said.
Also when I was new to photography I got the best ever picture* of action in a cricket match but it was from the far side of the ground so I tried to crop to get it to fill the frame but alas the crop/quality was poo, so I had to use the pic from a distance.
I coulda cried..



*Looking at it now it's not nearly as good as I thought at the time....his back is to me!

Nisio

Calina wrote: »

Enlarging I would endeavour to use as little as possible even though I have blown up two or three images to 2 or 3 metres across, very successfully.

what's involved in blowing a regular picture up to something that size? Is it as simple as resizing it in photoshop?

AnCatDubh

Nisio wrote: »

what's involved in blowing a regular picture up to something that size? Is it as simple as resizing it in photoshop?

The size that you can blow up something to is generally determined by how much megapixels (one case where it does tend to matter) remains in the crop'd image. Generally length X width (in px) divided by 300 (dpi) gives the size at which you can expect to reproduce an image i.e. 6 X 4 = 1800 X 1200 needed and so forth. The figure can be reduced to 200 (a figure I think stcstc posted previously) and still get a good result. So if you crop'd an image to under 1800X1200 (using 300dpi) and printed at 6X4 then you'd be in trouble. If you took the same image crop'd less than 1800X1200 and printed at 12X8 then i'm guessing that you'd have less than half of what you would normally need and consequently you'd be in trouble with your end result.

I think thats the gist of it anyhow.

If sizing upwards: If you don't have enough pixels to make your image and you resize then you may get varying results as software such as photoshop have to 'guess' as to what fills out the blanks - it has clever ways of doing this with various algorithms and methods but it doesn't equal having the megapixel value captured in the source image.

Anouilh

Thanks for all the helpful comments.

The original is here:

http://www.flickr.com/photos/anouilh/2615480315/

and a cropped version here just uploaded to the Boards thread here:

http://www.flickr.com/groups/boards_ie/pool/

stcstc

actually most SLR cameras will do image of between A4 and A3 at full resolution and the native res of the printer

printers vary from 300 to 360

so for example my 40d produces images which are 3888 * 2592

which from my printer which is 360 dpi native gives an image of 274 * 183 mm

BUT

it does depend what the image is for, how it to be displayed etc

i have printed image 6 metres wide from a D200, but they are viewed from 7 mteres away etc

so they look great