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Jay Gould
12-10-2009, 03:47 AM
The pursuit of BIF photography has raised an interesting question - at least for me. Until a recent post I had assume and acted upon the assumption that since a camera had "yonks" (an Aussie term for lots and lots) of pixels, large crops were acceptable. How else would you properly display small BIF captured from a distance?

Recently I posted an image of a Mockingbird that was cropped 83%.

http://www.birdphotographers.net/forums/showthread.php?p=399426#post399426

Until the discussion I didn't click that when you spread 17% of the remaining pixels over a 1024 x 800 image, you get a very different image than if you are spreading, e.g., 50% or 75% of the remaining pixels.

So, the discussion on the table: how much do you crop, how much is too much, and as a consequence of the necessity to crop BIF captured at a distance do you simply avoid shooting unless you have filled a certain amount of the frame?

All input gratefully appreciated and acknowledged in advance.

Alfred Forns
12-10-2009, 08:31 AM
Hi Jay

I do try to get a good size of the bird in frame and do not shoot dots in frame. I like to think it takes some skill. btw even if you have enough pixels to make a good image it shows ... in the dof :)

Understand the logic of having 20 MP cropping half and you still have more than with a 8MP camera at full frame ... so maybe I'm not making some sense !!! btw in contest that you need to send RAW images those dots in frame are not going to make it !!!

Scott Grant
12-10-2009, 08:48 AM
i don't like to crop an image any more than about 30-40% and even then don't like cropping that amount.

i feel it kinda absurd to spend 10 thousand dollars on gear to produce web size images. personally, i want images that i can print at a fair size.

Dan Brown
12-10-2009, 10:18 AM
I think that it depends on your end use of the image. If high quality presentation is your goal (prints, HQ web and slideshows, etc) a max of 30% seems to be it. But, if you photograph a rare species, event or behavior, IMO, I crop as needed to show what's important. I have been able to crop 70 to 80% in ACR and process selectively to reduce noise and increase sharpness to create usable (web/slideshow) images.I have started captioning these images as "heavy crops". For an example, I photographed a very rare gull species earlier this year here in CA and I cropped about 80%. It turned out the be the best image produced by anyone of that individual and is being used as a verfication of the presence of the species in the Central Valley of CA. This image will be used in a local bird rarity publication but, I would never print it for any other use.

Mike Milicia
12-10-2009, 10:26 AM
Until the discussion I didn't click that when you spread 17% of the remaining pixels over a 1024 x 800 image, you get a very different image than if you are spreading, e.g., 50% or 75% of the remaining pixels.

I have never seen a definitive study on the subject but this argument does not make sense to me.
As far as web sized images, e.g. 1024x800, I don't see how starting with a larger image and throwing more pixels away will in itself end up with better web image quality. If you have a truly tack sharp, perfectly exposed RAW file with no significant noise and apply proper postprocessing, I would claim that you could crop it down to 1024x800 and the quality of the resulting web image will be virtually indistinguishable from a full frame capture downsized to 1024x800. The problems come in if the initial RAW capture is not "perfect" to begin with. Another way to look at it is imagine that you have technically perfect capture from a 1D Mk III (3888 x 2592) and you generate a full resolution jpeg with proper sharpening for monitor display. If you view the 3888 x 2592 at actual pixels, I think most would agree that the image quality would be superb throughout. If you crop out a 1024x800 portion of the subject and are still viewing at actual pixels, that portion would still have superb quality as nothing has changed. The problem is that once you do such a large crop, the image is pretty much useless other than as a small web image.


So, the discussion on the table: how much do you crop, how much is too much,
I try to crop as little as possible (ideally not at all) and always indicate the amount of the crop when posting images for critique. But, as for "how much is too much?", it depends on the intended usage of the image. If all you ever care about is creating small images for the web, you can crop quite a bit. If the largest you will ever print is 4x6 images on note cards, you can't crop quite as much but you can still crop quite a bit. I have images cropped to 1500x1000 pixels which are indistinguishable in quality from a full frame image when printed at 4x6 on a note card. But, again, the images are pretty much useless for printing anything much larger. On the other hand, I have full frame Mk III images which all look great as 12x18 prints but when I try to print them at 20x30, some still work very well and others begin to show quality issues. It all comes down to quality of the original and the intended use.

Sabyasachi Patra
12-10-2009, 11:08 AM
Unless the bird or animal is large in the frame, I don't shoot. I rarely crop my images. Most of my images are full frame. I have seen people get carried away by the praise they receive and keep on photographing and posting 50-80% crops with heavy cloning and other post processing. If one is not careful, then there is a real danger of stagnating.

As an artist, I want to create photographs for myself. So there is no place for big crops or cloning.

Cheers,
Sabyasachi

Mark Theriot
12-10-2009, 11:22 AM
Great post! I've had the same question myself. In most cases, I'm lucky if I can get close enough to get a decent 50% crop (and I'm not satisfied with any of those images).

Yea, that's it! It's the 400's fault! I need the 500, and then I can use a 1.4x . . . yea, that's it!! (he self-justfies to himself . . .!)

Mark

Ed Cordes
12-10-2009, 12:13 PM
Jay, this is a great topic. I have found that many just crop away and don't worry about original image size. I must admit that years ago I used to do the same thing. Now I have learned that for high quality work anything less than 70% or so of the original is not good enough.
I know there is a tendency for those using high MP bodies to say they can crop more as they are starting with more pixels to begin with. The new 7D has spurred this argument. However, I find that even with 18 MP and great glass the image noticeably deteriorates at print output if I crop more than 30% away. I really try not to do even this much, but admit that I sometimes do.

Jim Fenton
12-10-2009, 01:15 PM
I think the simple answer is crop to your hearts content....as long as what you present isn't diminished in IQ.

The example presented by Jay IMHO looked degraded in many aspects due to not having enough left to work with.

Dan Brown
12-10-2009, 02:21 PM
So, here's a list of acceptable crop %, depending on end use and original quality. This is just off the top of my head, please add, delete or modify:D.

HQ large prints - 0 to 20%
BPN forums (exception-OOTB) - 0 to 30%
HQ web galleries/slideshows - 0 to 30%
HQ small prints - 0 to 50%
Web galleries/slideshows for education -0 to 90% depending on quality of original.
BPN OOTB forum - 0 to 95% as some illustration actions and software produce very nice “creative” effects with small, noisy files!

David Stephens
12-10-2009, 03:16 PM
I think that Dan summarized best, it depends on usage. I like his table of limits, based on usage.

Soon after I met Colorado-based wildlife photograph Bob Rozinski he warned me against getting too carried away with looking at the 100% image in my review and selection. Just because an eye doesn't look perfect at 100% doesn't mean that the image won't look great in a web page or even on a 4x6", particularly if there's an action or behaviour that will be of interest to other users.

BTW, one of Bob's main "guns" is a 600mm f4L, but he highly recommends the current EF 400mm f4L IS.

Dave

Ed Erkes
12-10-2009, 06:26 PM
I personally don't consider an image of mine to be successful unless it can be printed at high quality to at least 12" X 18". I won't ever crop more than 40% of an image and, of course, would always prefer a full-frame image. I use zoom lenses (Nikon 200-400 and Sigma 300-800) and try to crop with my zoom, but, even then, I often have to crop a litttle to get a better position of the bird in the frame for composition. Sometimes the AF sensor used is not compositonally in the best position.

Roger Clark
12-10-2009, 10:02 PM
It seems to me this is the wrong question as there is no right answer even for one individual. Let me explain.

How many years ago did we have 6 megapixel cameras and it was ok to crop those images a little? Well, now I have a 21 megapixel camera, so I can crop it a lot before I reach that former cropped 6-megapixel image level.

I always try and fill the frame with the subject, but again it is irrelevant.

None of the above is the point. The point is the subject, lighting and composition are more important. If you saw a spectacular subject with spectacular light but it was too small in the frame, would you not get an image?
For example, the image I posted in the "Why Bird Photography" thread,
http://www.birdphotographers.net/forums/showthread.php?t=48899
is a 3 megapixel image that was printed full page in Natures Best and has sold 16x18 inch prints in galleries. Sure it would be a better image with more pixels on subject, but I didn't have a choice. What matters is the image.

Roger

Bill McCrystyn
12-11-2009, 12:18 AM
But Roger, what size were those megapixels? Surely you would not argue that resolution with-out Genuine Fractals to intervene with res up is going to suffer on a log scale with enlargement.

The determining factor is the original quality of the image and then it is a matter of math assuming your after high quality on a minimum print size of 12x18. The bigger the print the less resolution. Generally my D300 at 12.3 megapixels with a modest crop is done at 12x18. My best print might push to 16x20 - maybe, viewed at a distance.

Roger Clark
12-11-2009, 01:02 AM
But Roger, what size were those megapixels? Surely you would not argue that resolution with-out Genuine Fractals to intervene with res up is going to suffer on a log scale with enlargement.

The determining factor is the original quality of the image and then it is a matter of math assuming your after high quality on a minimum print size of 12x18. The bigger the print the less resolution. Generally my D300 at 12.3 megapixels with a modest crop is done at 12x18. My best print might push to 16x20 - maybe, viewed at a distance.

I would argue that lighting, composition and subject trumps megapixels. And I have never used Genuine Fractals. The determining factor in how much t enlarge is in my opinion, again, lighting composition and subject.

The WOW factor in an image does include sharpness, but I would say it is last after lighting, composition and subject. It sure is nice when you have all 4 together.

Roger

Dan Brown
12-11-2009, 01:26 AM
So, the discussion on the table: how much do you crop, how much is too much, and as a consequence of the necessity to crop BIF captured at a distance do you simply avoid shooting unless you have filled a certain amount of the frame?

The question posed here by Jay is not "Cropping, how much is too much for a big print". His question is above. With all of the uses for digital images, the question is broader. I repost my little list here for another try at an answer to Jays question.

HQ large prints - 0 to 20%
BPN forums (exception-OOTB) - 0 to 30%
HQ web galleries/slideshows - 0 to 30%
HQ small prints - 0 to 50%
Web galleries/slideshows for education -0 to 90% depending on quality of original.
BPN OOTB forum - 0 to 95% as some illustration actions and software produce very nice “creative” effects with small, noisy files! <!-- / message -->

Bill McCrystyn
12-11-2009, 01:45 AM
Dan, cropping and enlargment is 6 of 1 - half dozen of the other. When you crop an image you are doing the same to it as if you had enlarged it. That is unless your end result is to create a smaller image than you began with. It is a question of how far can you stretch the pixels across the screen or print before your resolution becomes less than high quality because you don't have enough pixels to fill the voids/gaps between them.

If all Jay wants to do is cut a small area out of a big picture and NOT enlarge it - for what-ever that might be useful, then the only restraint would be, how small you could use it and still see the the image. :D

Jay, are we missing something here?

Ed Erkes
12-11-2009, 06:42 AM
It seems to me this is the wrong question as there is no right answer even for one individual. Let me explain.

How many years ago did we have 6 megapixel cameras and it was ok to crop those images a little? Well, now I have a 21 megapixel camera, so I can crop it a lot before I reach that former cropped 6-megapixel image level.

I always try and fill the frame with the subject, but again it is irrelevant.

None of the above is the point. The point is the subject, lighting and composition are more important. If you saw a spectacular subject with spectacular light but it was too small in the frame, would you not get an image?


Roger

For me the size of the subject in the frame is not irrelevant. If a spectacular subject in spectacular light is too small in the frame, I personally wouldn't take the image---Unless the image would work as a "bird in the habitat" image. I agree it is a personal decision. I'm not a professional photographer. I do it for the fun of it, but I want the best quality images I can get. It is a standard that I have set for myself and I strive to make all my images meet it. I don't consider them successful if they don't. That is part of the challenge and sport of wildlife photography. I share images on the web sometime, but I don't shoot to make web jpgs.

Jay Gould
12-11-2009, 07:03 AM
Hi ALL and thanks for playing yet another BPN "lets all learn from each other" game.

If you look at the Mockingbird thread and Artie's comments, that is what caused me to start this thread.

The OP was cropped to 17%; 83% of the pixels were eliminated. The remaining cropped image was 1699 x 1558 and that was then "squashed" for posting on BPN with limits of 1024 x 800.

Artie responded, if I understand corrrectly, that the IQ of the posted image would have been better if, for example, 50% of the captured pixels had been compressed to BPN size instead of 17% of the captured pixels.

Why does the significant cropping degrade IQ?

To go the enlargement/printing route I am only going to print up to 12 x 18. When you enlarge a heavy cropped image as compared to enlarging the original image, doesn't the resulting images have very different IQs?

Perhaps I am not asking the corrrect question - I think you know what I am trying to learn.

Harshad Barve
12-11-2009, 07:31 AM
Just to add my 2 cents
I dont crop any of my image more than 20-25 % ( means 80-75 % of original remains ). After using 12k $ Nikon equips for wildlife , I feel that I should be able to print it atleast 20 x 30 ,

ps , I dont have technical experties about how much MP are required in image to print it in 20 x 30 inch

c.w. moynihan
12-11-2009, 08:32 AM
Obviously in a perfect world, one wants to crop as little as possible. It all depends on your output. If your printing, the size of the crop will be a much bigger factor than if your output is for a web displayed image. You would be surprised how much you can crop for a web image and have it still look good to the eye.

Bill McCrystyn
12-11-2009, 11:24 AM
As Roger has well pointed out, the composition is going to determine to a large degree how much resolution your image can afford to lose. Landscapes are generally less demanding and some actually prefer a soften content. BIF images typically require more sharpness and therefore, albeit resolution should not be compared to acutence, Sharpness will suffer with the lack of pixel density and therefore should be keep to a minimum. I have seen charts online that will give you the parameters you want - megapixels/IQ - but with PS, they can be cheated and pushed larger. As they said Jay, it is difficult to put an exact number on it. It depends on your requirements and the subjects image resolution and composistion. If you can sell it or show it with pride, you have what you need.

Desmond Chan
12-11-2009, 07:42 PM
Obviously in a perfect world, one wants to crop as little as possible. It all depends on your output. If your printing, the size of the crop will be a much bigger factor than if your output is for a web displayed image. You would be surprised how much you can crop for a web image and have it still look good to the eye.

I second this answer.

I think in general, to decide whether to crop or not you should also consider what you want to show and tell in the final image. Cropping affects composition and composition could affect the story you want to tell. If you consider yourself an artist and creativity is part of your game and you want to have the final say of what you want to show, then why are you limiting yourself to the frame determined by your camera?

Alan Lillich
12-11-2009, 08:12 PM
I think Roger is right, but maybe it can be said more bluntly:

1. It is art. There is no right or wrong. The final image is what matters.
2. The highest quality starting point is to get as close to that final image as possibly.
3. How far from that you're willing to stray is personal taste. Each viewer, including the creator as a viewer, gets to say how good it looks to them.
4. It takes a lot less pixels than many think to have a really nice looking image.

Alan