michlis
Posts: 696
Joined: Sat Jul 21, 2007 8:13 am

Understanding Cropping And Sizing

Sat Oct 06, 2007 12:36 am

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.
 
Fly747
Posts: 1361
Joined: Sat Apr 16, 2005 9:03 am

RE: Understanding Cropping And Sizing

Sat Oct 06, 2007 2:27 am

What editing software do you use?

Ivan
 
NX622
Posts: 26
Joined: Wed Mar 16, 2005 5:22 pm

RE: Understanding Cropping And Sizing

Sat Oct 06, 2007 2:43 am

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:

http://www.airliners.net/procphotos/reasons.php#soft

There is also a pretty good introduction to editing written by a photographer located here:

http://www.airliners.net/addphotos/PsProc.pdf

I'm still learning myself so hope this helps!

Glenn
 
unattendedbag
Posts: 2156
Joined: Wed Oct 08, 2003 10:35 pm

RE: Understanding Cropping And Sizing

Sat Oct 06, 2007 3:21 am

Quoting Michlis (Thread starter):
I'm pretty much a nub,

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
Slower traffic, keep right
 
RyDawg82
Posts: 833
Joined: Fri Sep 14, 2001 8:30 am

RE: Understanding Cropping And Sizing

Sat Oct 06, 2007 3:23 am

This will be a basic question, but when doing a crop in Photoshop, you can specify height, width, and resolution. Can someone explain the resolution part and the various settings?

Ryan
 
Stealthz
Posts: 5549
Joined: Wed Feb 02, 2005 11:43 am

RE: Understanding Cropping And Sizing

Sat Oct 06, 2007 5:03 am

Ryan,
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

Cheers

Chris
If your camera sends text messages, that could explain why your photos are rubbish!
 
CalgaryBill
Posts: 618
Joined: Thu May 04, 2006 12:27 am

RE: Understanding Cropping And Sizing

Sat Oct 06, 2007 6:43 am

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.

No math required.  Smile

B
 
dendrobatid
Posts: 1646
Joined: Sat Nov 06, 2004 3:40 pm

RE: Understanding Cropping And Sizing

Sat Oct 06, 2007 8:04 am

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  Sad

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.
Mick Bajcar
 
CalgaryBill
Posts: 618
Joined: Thu May 04, 2006 12:27 am

RE: Understanding Cropping And Sizing

Sat Oct 06, 2007 9:19 am

Quoting Dendrobatid (Reply 7):
No maths required......nor any thought

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.

B
 
michlis
Posts: 696
Joined: Sat Jul 21, 2007 8:13 am

RE: Understanding Cropping And Sizing

Sat Oct 06, 2007 11:34 am

Quote:
You still haven't answered with which software you're using.

That is because I was sleeping.


I use Photoshop Elements 2. Thanks for the work flow on cropping. Now it begins to gel.
If you know the enemy and know yourself, you need not fear the outcome of a hundred battles.

Who is online

Users browsing this forum: river38 and 8 guests

Popular Searches On Airliners.net

Top Photos of Last:   24 Hours  •  48 Hours  •  7 Days  •  30 Days  •  180 Days  •  365 Days  •  All Time

Military Aircraft Every type from fighters to helicopters from air forces around the globe

Classic Airliners Props and jets from the good old days

Flight Decks Views from inside the cockpit

Aircraft Cabins Passenger cabin shots showing seat arrangements as well as cargo aircraft interior

Cargo Aircraft Pictures of great freighter aircraft

Government Aircraft Aircraft flying government officials

Helicopters Our large helicopter section. Both military and civil versions

Blimps / Airships Everything from the Goodyear blimp to the Zeppelin

Night Photos Beautiful shots taken while the sun is below the horizon

Accidents Accident, incident and crash related photos

Air to Air Photos taken by airborne photographers of airborne aircraft

Special Paint Schemes Aircraft painted in beautiful and original liveries

Airport Overviews Airport overviews from the air or ground

Tails and Winglets Tail and Winglet closeups with beautiful airline logos