Resizing for others 2?

[elm54]

I posted this in the software section but thought I might get more of a response here....

I am experimenting editing images for web and other computer viewing. I am having trouble coming up with a formula for resizing and cropping. I think an image should be self stating even if not dramatic. But alot is lost if objects can't be identified on different computer monitors due to lost resolution or sharpness.
I have these images: www.pbase.com/elm54/resize
the first ( acornLg.jpg) is close to what came up from Adobe Camera raw without posting the original . the second ( EmAc.jpg ) I sent to a couple of folks in an email resized accordingly. And the third I sent to "explain" the emailed version.
Now I can see quite clearly the acorn in the PSD image I first started with . the problem is it gets progressivly more difficult to identify as I resize.
The question is: How do you do it so it stays sharp as you resize for different viewing media.
Large topic I know but any inputs would be useful.

Thanks
Eric

[Leighow]

ERIC

This is really related to the optics of "eye" as a lens and photographic composition.

OPTIICS
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The same question relates to sizing text. How for you size text so that it is readable on an 8 1/2 x 11 sheet of paper ( to be viewed from a distance of 2 feet) vs an overhead transparency ( to be viewed 50 feet away).

The answer lies in the "eye" as a lens and the distance that the viewer is from the text (or image detail). I must admit that I forget what the eye can resolve at say a distance of 2 feet., but lets guess that it can pick out a circle with a diameter of 1/32 of an inch.. If so, from there on, everything is linear: the eye can see 1/16 in at 4 ft .. or 1/64 at 1 ft … 1/128 at 6 inches … and so on.

YOUR ACORNS
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So, I was unable to see your acorns in the first two thumnails, but I could see it in all the 5 in x 5 in jpg's. But note, optics aside, I would not have known that this was an acorn had you not told me so! Sharpening would not have helped! I needed more clues – like the side of the acorn to conclude that this was indeed an acorn.

COMPOSITION et al
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The related question concerns subject and composition. In all of these shots one is drawn to the bark of the tree. The acorn seems like a side issue, except perhaps in the case of the last image. If acorns were red and looked like a rose, I guess that we would be drawn to it. Even then, we might be wondering why you did not close in on this subject, as it too would seem lost in a sea of bark.

CONCLUSION
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I suspect that a good photograph leaves the viewer little doubt as to its subject. Leading lines, perspective, perhaps colour, and other compositional tools are employed by the photographer to draw the user to the image’s focal point. When that focus is a needle in the haystack, it is probably going to be overlooked – unless it is the subject of a close-up.

HOWIE

[elm54]

Howie,
Thank You for taking the time to reply to my post. You put it well about it being an optical question. and What you said about composition is good info. I am asking though, about resizing from the original image to post to a web site or for email purposes so that there is a minimum of loss of definition or clarity in the image. I admit my photo of the tree with an acorn in the hole is not composed well to show the acorn. Until the crop.jpg which was meant to show exactly what was in the hole.
The original 36mb image had no trouble disearning the acorn, but as I resized ( acornLG.jpg & EmAc.jpg ) I started losing that clarity of detail. You are right if the acorn was a red rose it probably would not be that hard to identify though I think the same loss of sharp definition would occur.
My question was more of a technical mechanical nature than an artistic one. That's kinda why I used the acorn tree image. The acorn is not neccessarily the subject but it was a nice surprise. On my monitor I have no trouble identifying the acorn on the original (partly because I know it is there) . But it is clear.
I have seen some great posts here that seemed to lose no detail when resized for downloading to the Net. I was hoping some would share their method of this resizing from the original 2048x1360 to say 640x480 at whatever dpi they use.
Thanks again for your answer The optics lesson is food for thought and now to try to achieve that in image editing for monitor viewing.

Eric

[stopbath]

As you resize, you loose information.

As you make the image smaller, you display less information that the user can tell if that is an acorn, bottle cap or small stone.

If you wish to resize to a small image, your original image must have as much information as you can pack in. Get close to the subject and keep things simple so that the smaller image is not just a jumble of clutter too.

A full length portrait will not resize as well as a closeup portrait of the same person. The full length will become a 'person' without identity while a close up of the face still looks like the subject.