Michlis From United States of America, joined Jul 2007, 737 posts, RR: 2 Posted (8 years 8 months 1 day 5 hours ago) and read 2655 times:
When it comes to photo processing, I'm pretty much a nub, but one area that really has me scratching my head is cropping/resizing. In particular, concepts such 3:2 and 4:3 ratio have me a bit perplexed as to their application to an image I am editing. In particular, I am having difficulty cropping my image and then resizing them to Anet-allowed sizes. Is there a resource or work flow that I could access to help explain this?
(Edited for clarity)
[Edited 2007-10-05 17:37:25]
If you know the enemy and know yourself, you need not fear the outcome of a hundred battles.
Nx622 From Australia, joined Mar 2005, 31 posts, RR: 0
Reply 2, posted (8 years 8 months 1 day 3 hours ago) and read 2655 times:
As far as I understand it, the 3:2 or 4:3 is the ratio long side to short side. Some photos work (look) better when cropped differently, hence the option. There is a short section explaining the various size options here:
You are a n00b. If you have lost a finger in an industrial accident, you have a nub.
Quoting Michlis (Thread starter): concepts such 3:2 and 4:3 ratio have me a bit perplexed as to their application to an image I am editing. In particular,
Here is a little math for ya!
When you have a photo with a ratio of 3:2, that means the width is 3 units and the height is 2 units. That may not make much sense so I will give you a real world example. You will find that must photos uploaded to this site are 1024 pixels by 683 pixels. 1024 / 3 = 341.3 and 683 / 2 = 341.3 1024:683 and 3:2. For every 3 pixels wide the photo is you need to make the photo 2 pixels high.
Say you want to make a photo really big but still retain the 3:2 ratio. Pick a width, say 1600. Now divide 1600 by 3 and you get 533.3. Now, multiply 533.3 times 2 and you get 1066.6. that is your ratio. 1600:1067
StealthZ From Australia, joined Feb 2005, 5898 posts, RR: 38
Reply 5, posted (8 years 8 months 1 day 1 hour ago) and read 2655 times:
If you are cropping/resizing for online or screen display set the crop dimensions in pixels i.e 1024w x 683h, leave the resolution setting blank.
If you are cropping to print then you can set a size i.e 6"w x 4"h and a resolution of 300dpi (or whatever output resolution your device requires.)
Remember the cropped area must have more pixels than the desired output or the quality will suffer.
This answer along with UnattendedBag's & Nx622's barely touch the surface of what is a deceptively complex subject.
I have been thinking about writing a tutorial on cropping, resizing & resampling, not sure if I should or would my efforts be better spent locating a good one someone else has already done.... mmm maybe another A.net MasterClass
If your camera sends text messages, that could explain why your photos are rubbish!
CalgaryBill From Canada, joined May 2006, 686 posts, RR: 5
Reply 6, posted (8 years 8 months 23 hours ago) and read 2655 times:
You still haven't answered with which software you're using. But if it's photoshop, the answer is really simple:
Select the crop tool. The tool's options will appear in the toolbar along the top of the picture. Set 4 for width and 3 height (or 3 and 2, whichever suits your image) but leave the resolution blank so that your picture isn't sampled. Now when you click and drag the cropping tool it will automatically crop to the aspect you set.
Once that is done, you can resize the picture with Image - Image Size. All you have to do is set the width you want (1024 as mentioned above is popular) and the height will automatically be filled in for you.
Dendrobatid From United Kingdom, joined Nov 2004, 1732 posts, RR: 54
Reply 7, posted (8 years 8 months 22 hours ago) and read 2655 times:
Quoting CalgaryBill (Reply 6): Once that is done, you can resize the picture with Image - Image Size. All you have to do is set the width you want (1024 as mentioned above is popular) and the height will automatically be filled in for you.
No maths required.
No maths required......nor any thought
There is an acceptable range between 3:2 and 4:3 and I see a lot of images at one end or the other of that range when the image would look much better at the opposite end of the range. Select any side-on images on the database and check their sizes and despite most of our subjects being inherrently long and thin and it will not take long to find some at 1024 x 768.
I use a freehand crop tool to level and crop (the whole crop can be rotated for levelling by going to the corner, clicking and moving the mouse). I compose the image to what looks best crop and resize (ctrl+Alt+I) simply making sure that the size is within the permissible range.
You end up with an image that is cropped, levelled and, importantly (though frequently ignored) composed all in one go.
That was not my intention at all! I consider photography to be artistic expression and was offering a way to compose the shot without getting mathematical about it. Just because someone doesn't include math in the approach doesn't mean it can't be considered, thought-out or creative.
The tool is there to simplify execution of one aspect of the work - it's up to the photographer whether they use the "extra" time to snooze or to put more thought into the creative side of their work.