I know what cropping is, but I cannot understand how to do a e.g 50 and or 100% crop. Are there certain parameters in a cropping program that let you the size of a crop.
Thanks for your help.
Wally
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I know what cropping is, but I cannot understand how to do a e.g 50 and or 100% crop. Are there certain parameters in a cropping program that let you the size of a crop.
Thanks for your help.
Wally
The "100%" refers to viewing the image at 100% size on your display. With current cameras, you'd need higher resolution displays than are currently made to view the entire image at 100%, so you can only see a portion at a time. When someone posts a "100% crop" or a "50% crop" here, they are viewing the image at 100% or 50%, then cropping by selecting a portion of that image and copy/pasting it into a new file, which they post here.
Personally, I use Photoshop for that, setting the View to Actual Pixels for 100%, then using the marquis selection tool (usually with a fixed size since the max width of an image here is 800 pixels) to copy the desired portion and paste it into a new file.
Another method would be to use any image viewer (DPP, etc.), set the view to 50% or full size, reduce the size of the window to something managable, then take a screenshot of that active window (Alt-PrtScn on Windows then paste it into some other program, or Command-Shift-4 then Space Bar on Mac, although on Mac it's easier to just set the view to 100% then useCommand-Shift-4 and drag the selection box to grab a portion of the image which is saved to the desktop).
For example, here's an original image and a 100% crop of that image:
http://farm5.static.flickr.com/4154/...df64efd0_b.jpg
http://farm5.static.flickr.com/4079/...711dee05_o.jpg
Note that you have to actually show the full size of the cropped image, which I why I selected an 800 pixel wide portion of the original image viewed at 100%. If you display the cropped image at less than full size, like the image below, it's no longer a 100% crop. That's important not just for viewing size - notice that the noise which is evident in the full size 100% crop above (ISO 3200 on a 7D) is much less evident in the smaller image below. The noise is also less evident in the original image, which is why extreme cropping has a negative impact on a final image.
http://farm5.static.flickr.com/4079/...f58b3878_m.jpg
Hope that helps.
--John
Thanks for the info John
Your explanation is very good. I will try your method and will let you know how I went.
Thanks again Wally
You don
Wally
You see people say 50% and 100% crop, I am not sure they are mathmaticaly trying to make those exact crops. I haven
Quote:
Originally Posted by HDNitehawk
The main (perhaps only) reasons would be to compare performance of different cameras/lenses or illustrate some technical point about an image. If someone actually needed to use a 100% crop as a final image, it would be time to get a longer lens...
The reason for the exact 100% crop size is to compare lenses, or show camera noise levels. That sort of thing. It can show lens sharpness, contrast, amount of chromatic aberations on high contrast edges. For comparisons, it
Quote:
Originally Posted by neuroanatomist
I could see where it isgood for comparative purposes. Usualy when someone mentions a 100% crop they are trying to either show how sharp the image is or a flaw. Most of us know what 100% looks like on our own computer.
The only lens I have that is likely to be croped to 100% for a final image often, is the one that really can't get any longer with a truck load of cash. The 500mm its is very common especially with small birds, like a finch atminimum focal distanceyou wouldhave a sizeable crop (not 100% though). Still you wouldn't do the exact number 50% or 100%.
Quote:
Originally Posted by DavidEccleston
David
I like to do big prints. And the way I judge how well my lens and camera perform together is by the 100%, 200%, 300% to 500% full views on the computer screen. The ones that can only make it to 100% are usualy marginal. and can't take much croping at all for a big print. At least for my use.
Actually when I read the OP, I was thinking finished product and not comparison
I can releate to the story about the zooming in on the brand name of the zipper. I don't know how many times I have had my 5D IIwith the 35mm lens on and someone ask me to "Zoom" in with my camera to see some detail or what somthing says. At least a dozen times I have had to explain the diffrence in a wide lens, telephoto lens and zoom lens to someone asking. ...But I still take the picture and zoom in on the viewer to see if I can see it. The most memorable time someone asked was at Mt Rushmore. I had the 500mm with 1.4x on and we took a head shot of George Washington, zoomed in on his eye lid. There is a steel spike sticking out of the eye lid on George Washington.
Rick
An x% crop is simply a portion of the original image that has been resized to x% of its original pixel dimensions.
Let
I enoy reading how others have different approaches or methods of achiveing the same ends. So, I will throw my two cents worth in:
I normally use lightroom and since lightroom doesn
I think where some people get confused about the term 50% or 100% crop is because the term is kind of misleading in the way it is often said.
After all if it is 100% crop then did you really crop it? if you crop 100% of the picture you're left with nothing aren't you? [:)] Those are Rhetorical questions!
Actually it's the difference between showing a 100% crop or cropping 100% of the image. Obviously it's not cropped 100%
As described already, by viewing the original image at 100% on your screen, setting your crop size to the desired dimensions so that when you crop the image it shows that portion at the same size you see it in the full image without having to re-sample(re-size) it when viewed at 100%. The idea is to show the cropped portion of the image without any interpolation. That is what is referred to as a 100% crop and has nothing to do with the actually percentage of the image you cropped it down to. If that were the case then if I were to crop one of my pictures (4752 x 3168) down to 800 x 640 for example, then I am only cropping about 17 to 20% from the original picture. That's the percentage of the original image size/dimensions, and then a 50% crop would be half the pixel height and width of the original. Understandably, this is why I think some people get confused about the term, and programs such as Photoshop don't make it any less confusing. Photoshop for example has the ruler guides that can be set to show inches, mm, cm, picas, pixels and percentage which is a great tool to aid when cropping photos down to certain sizes for whatever reasons. If you use Photoshop or something similar and want to show a true 100% crop use Pixels rather than Percentage on the ruler guides, Size your crop box to the desired pixel dimensions then move it over the portion you want to keep. Or use the rectangular marque tool and set the fixed size then slide it over the portion of the image you want. Either way works.
When photo editing / image processing, working on an image when viewed at 100% vs whatever size to fit your screen has advantages and will have better end results.
Here are 2 examples using the PS fixed marquee tool.
[img]/resized-image.ashx/__size/800x0/__key/CommunityServer-Discussions-Components-Files/13/2046._5F00_002-copy.jpg[/img]
[img]/resized-image.ashx/__size/800x0/__key/CommunityServer-Discussions-Components-Files/13/2402.cats-eye2.jpg[/img]
[img]/resized-image.ashx/__size/800x0/__key/CommunityServer-Discussions-Components-Files/13/0284.Cats-eye-copy.jpg[/img]
Wow What a shot Tom. LUV It
Nicely Cropped too
Wally
Haha this thread is genius!! I thought I had a clear view on a 100% crop, but after reading some replies I got confused nonetheless [:D]
The point where it goes wrong is in the name. It's not a 100% crop...(yes we call it this way)
It's actually very simply said a crop of an image that is shown full/100% scale..
Actually when you are looking at the 100% view of your image, you're not zooming in, nor are you zooming out. (to make it even more confusing)
Actually most people view their photo's zoomed out [:|] How's that might you be asking...
Say you have a full HD screen. That would mean you have 1920 horizontal pixels * 1080 vertical pixels. A total of 1920*1080=2073600 pixels = 2 Megapixel. At a 16:9 ratio.
If you were to have a camera that shoots 2MP photos at a 16:9 ratio. You could view your photos at full scale all the time, since the monitor isn't a limitation.
With modern day camera's we often have much bigger photos than the monitor can handle at once. If I have an image of 6MP: 3000*2000p. All you can see is 1920*1080p at a time. Since that's what my monitor can handle. This means that if you want to view your image at full scale, you aren't able to see it entirely. You'd miss 1080 pixels horizontally (3000-1920) and 920pixels vertically (2000-1080)
That's not what we want in general and therefor pretty much every photo viewer scales your image down to view the entire photo. So it's actually zoomed out to fit your screen [A]
Anyway, to make a "100% crop" as we use it here, is easy. The photos on the forums are limited to 800p wide. If you have photoshop, use the rectangle selection tool with a fixed size of 800p wide and use the crop tool to make your "100% crop" .
If you don't have photoshop or a program where you can select your selection wideness, there's another option. See which screen resolution you are using. In windows it's a simple right click on the background and go to options or something.
I for instance use a 1920*1080 resolution. If I need to make a 800p "100% crop" I could also " guess" how wide I need to go. 800p is approximately 1/2.5 width of the screen. (1920/800)
Crop for that part and you are very close to a "100% crop" without the need of photoshop or another difficult program. Close enough to use here for to show your "100% crop".
That's my 2 cents,
Jan
Jan
I
Quote:
Originally Posted by bouwy
Glad you do, because I still don't [;)]
When we're really talking about cropping and not about our genius "100% crop" it seems logical that a 50% crop is half of the images total surface. That would mean that a 25% percent crop would be 25% of the original photo left intact(case 1). Or does it? Does it mean that 25% is cropped off/deleted(to avoid different interpretations)?(case 2)
In case 1, where a 25% crop means that you're left with 25% of the original photo, a 100% crop would be theoretical " possible". Albeit, you're not really cropping at a 100% crop, since you're saving the full image [;)]
In case 2, a 100% crop is also impossible [8-|] since cropping means that you're adjusting the original thing by cropping stuff away and it's kind of hard to crop away 100%. It's like taking a 1m hose and telling you to cut off 100% of the hose. That's simply impossible, because you don't have to cut at all to remove 100% of it...
Either case would mean that a 100% crop isn't even possible, right...[:S] Someone please explain all this to me.
Obviously this is other cropping than the "100% crop" we use at this forums. Getting confused yet?
Holy <s>crap</s> crop, this is more confusing than I thought!
For demonstration purposes I will post a picture with everything cropped 100%
As you can see nothing is left
Quote:
Originally Posted by HDNitehawk
Perfectly understandable demonstration
I think we should congratulate Jan, he has succeeded where many failed.
He has confuse Neuro
Quote:
Originally Posted by HDNitehawk
You should include the picture next time [;)]
For the same demonstration purposes I have a self-portrait with myself being 100% cropped. See how sharp my lens is at 100% crop?
http://www.actieinbeeld.nl/tdp/cropping.jpg
Quote:
Originally Posted by HDNitehawk
Hahaha! Thanks, I feel honored [:D]
Hehe I just come to think, it's not only confusion. He's probably going nuts by now thinking about all those posts where he used "100% crops" [:P] Haha sorry John[A]
Quote:
Originally Posted by HDNitehawk
You should include the picture next time [;)]
For the same demonstration purposes I have a self-portrait with myself being 100% cropped. See how sharp my lens is at 100% crop?
http://www.actieinbeeld.nl/tdp/cropping.jpg
Quote:
Originally Posted by HDNitehawk
Hahaha! Thanks, I feel honored [:D]
Hehe I just come to think, it's not only confusion. He's probably going nuts by now thinking about all those posts where he used "100% crops" [:P] Haha sorry John[A]
I guess my 800x533 crops from a T1i would have been 2.83240656% crops. :)
Quote:
Originally Posted by DavidEccleston
Or 97.1676%....that's the big question [;)]
I personally think it's a 97.1676% crop or either a 2.83240656% leftover [:#]
OMG [:'(] I just read that there's such a thing a 200% CROP... Can any one explain EXACTLY[:P] what 200% crop is.
Wally [I]
You want to learn a magic trick? [<:o)]
By the way, Wally I'm pretty sure that you must be so glad that you started this thread [A]
Good idea for Assignment 19: Create the most interesting crop of your photo
Jan, I
Quote:
Originally Posted by bouwy
Wally
This is really quite simple. If you look at Jan's previous post where he croped 100% of himself out of the picture, if you then crop 100% of the background, then you will have a 200% crop.
Where 100% + 100% =200%
Rick
Rick... That's a Classic I drink to that [D]