simple post processing of images

Discuss cameras, settings, composition, or anything related to photography - cactus or other subjects.
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hob
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simple post processing of images

Post by hob »

Firstly most digital cameras have a setting for image quality and image size, set both to the highest setting, with my camera this produces an image 3648 pixels wide by 2736 pixels high 4.6Mb in file size

Image

this is the image above as taken, just resized to 600 pixels wide and 450 pixels high to fit this page and reduce the filesize for uploading

the filesize is now reduced from 4.6Mb to 47Kb

Image

before resizing the image can be cropped to just show the bits you want then resized for uploading like this
the image is now 600 pixels wide and 510 pixels high file size 45Kb

Image


one of the reasons for using the highest settings is you can do extreme cropping without too much loss of detail like this
this image was zoomed to 70% of full size before cropping then resized to 600 pixels wide by 451 pixels high file size 35Kb
Image



so far all we have done is shoot at the best settings, crop the image and resize, most software packages will let you click "auto levels" to alter contrast, brightness and gamma. if i don't like the result i click undo and play with the levels setting which allows you to set those manually.

a note about software, some software can cost loads of money and you can spend dozens of hours learning all the complexities of how it works

examples are
Adobe Photoshop Extended Price: Purchase; $999.00 to buy

PaintShop Photo Pro X3
Full price £ 59.99


or you can check out the free stuff here

http://download.cnet.com/windows/image-editing-software (click on free on the left hand side)

i use a very old copy of ACDSee V6 which iv'e had for years (guess i just got used to it)

they are on V 12 now US$69.99

http://store.acdsee.com/store/acd/en_US ... 5669607237

which software you use is up to you and is down to a mixture of price, usability and personal preference.

this article is intended to show what can be done with the right camera settings and fairly basic editing techniques.

all 3 images above were taken from the same original image

happy snapping
hob
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Harriet
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Post by Harriet »

Hob,

I have no argument with your method, but I do want to say that setting the camera to the highest resolution and largest image size is probably over kill, especially with the newer digital cameras.

I think that as long as you have the Resolution set to the highest level ("Fine" on a Nikon) you can reduce the image's physical size without noticeable degradation of the image. The large file size sometimes just means that your image is densely loaded with information that you may not need at all.

For example, if you were to print out your 3648 x 2736 pixel image at 200 dpi, the resulting print would be approximately 18"x13", and I'm guessing that you can't use a print that large, or, at the very least, you can't use your pictures as background pictures on your PC without modification because they are way too large.

If you do nothing but crop the image it will probably still look good. But when you start compressing the image you loose resolution and the quality of your image... most image editing programs reduce the file size by compressing the image, combining blocks of pixels, which reduces file size by reducing the amount of information (pixels in this case)in the image.

The newest digital cameras will capture so many millions of pixels per picture that they are almost meaningless to the average photographer. A 10 Megapixel camera, for example, has a CCD capable of
producing an image containing up to 10 million pixels, where a 6 Megapixel camera’s CCD has the capability of producing images with 6 million pixels. Yes, the image is 4 million pixels sharper, but it is getting to a point where most people could never see a difference in most pictures.

My point here is that if the Resolution is set to the highest level, the physical size of the image becomes less important. So you don't have to create an image with the absolutely largest file size to get the best picture, you can get away with high resolution and medium image size and no one will know the difference. Heck, they might not notice even with the smallest image size.

I'd also like to play Devil's Advocate with the need to crop. I believe that you should crop the image in the viewfinder as you capture the image so that you don't have to do so much post processing... Unless of course, that is what you like to do. To that, all I can say is GO FOR IT!
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hob
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Post by hob »

Harriet wrote:Hob,

I have no argument with your method, but I do want to say that setting the camera to the highest resolution and largest image size is probably over kill, especially with the newer digital cameras.
Harriet, on this issue i plead guilty to not thinking "outside the box" i get so used to thinking in terms of my own camera that i forget things have moved on in the last few years.
Harriet wrote: I'd also like to play Devil's Advocate with the need to crop. I believe that you should crop the image in the viewfinder as you capture the image so that you don't have to do so much post processing... Unless of course, that is what you like to do. To that, all I can say is GO FOR IT!
i have to defend this side of things as i can get to things i can't physically get the camera close enough to or focus onto well enough in any other way, this image would be imposable to do "in camera"

Image
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Harriet
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Post by Harriet »

Your method produces, with out a doubt, some extraordinary photos. But here is a comparable shot (admittedly without the same clarity) taken with nothing special on the camera... not even a tripod. Only cropping was in the view finder.

Image

And here is the same shot cropped without any compression to 600x900 pixels.

Image


So I think it is safe to say that either method works well, and however the photographer chooses to capture a closeup, there is not one way that is better than another.
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iann
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Post by iann »

It isn't always possible to crop small enough in the viewfinder, and then you want all the pixels possible so you have enough left when you've finished cropping. Maybe 90% of the time you don't need all the pixels at full resolution, but sometimes you do and you can't get them back later. You need about three times the image width, or ten times the number of pixels, to print at the same image size as you view on the web.

I wrote an essay on digital camera specs especially concerning sensor pixel sizes. It turned into a rant. I deleted it. Suffice it to say if you don't use your camera at full resolution, why have so many pixels? Not always easy to avoid these days, but worth thinking about.
--ian
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Harriet
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Post by Harriet »

You have a point Ian. I sometimes think that getting a camera with 20 bajillion megapixels is like buying a Bugatti Veyron... So what if you have it, where could you possibly use it?

I do have my camera set to take advantage of full resolution, I just don't set it at the largest image size.
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Shmuel
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Post by Shmuel »

Wow! A photography section!!! At last! :D :cheers: =D> :hello1: :laughing5: :love7: Very exciting!

My 2 cents are that I have a dinky Canon 540 and I totally use the Hob system of top resolution and top size. Truth is, I never know when a particular photo will be the one I want to crop - so they all are and it is no sweat. If I want to make a print, I am glad I have the size and quality and it is easy to pop it down to cactiguide friendly proportions. Maybe I would think differently if I had a new camera (and Harriet's comments are great for that case), but I don't and this works great for me.

Also, and I really do not have an answer, if I am further away from the subject (with intention of cropping later for the close-up) I think I can get a much greater depth of field. I don't know though so maybe someone has thoughts on that.

Shmuel
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