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BobTrips
12-05-2002, 06:49 PM
So many shots are in need of sharpening (IMHO).

Why is this? Do people not know how or is there some idea that once you snap the shutter it's a sacrilege to do anything further?

I shot slide film for about 35 years. I worked hard to get the best possible shot as I was going to have no opportunity to fix any problems once the shot was made. However, I aligned the screen and adjusted the focus on the projector when I displayed my slides.

mdchachi
12-05-2002, 08:04 PM
I think it's mostly a lack of knowledge. Plus the fact that most basic (free) image editing programs don't have this feature, or if they do they're not in obvious places (not as obvious as the focus adjustment on a slide projector). I've had a digital camera since 1999 and only discovered how to sharpen about a year ago.

sam
12-05-2002, 08:54 PM
Bob, I think the answer to your question involves a number of things. First, it is clear from the lack of color/contrast/levels correction on many images posted here that often no post-processing is being done to match the online image to the original. For those who try, there is the difficulty of fully understanding the unsharp mask tool (for those who even have access to the software). I have to admit to not having fully mastered sharpening myself. (It would be nice to see some links to good tutorials posted here.)

Having said that, I would argue that not as many images as you suggest need sharpening. Or maybe a better way of putting it is that the solution to many problematic images is in the picture-taking, before post-processing even begins. Unsharp mask is not a solution to poor focus (or DOF) or poor hand-held camera technique that leads to motion blur. In my opinion, excessive sharpening to compensate for these shortcomings is a cure worse than the disease because of the artifacting it imposes on the image.

Further, I don't think everything is meant to be absolutely sharp (e.g. portraits, moving objects, trees blowing in wind, etc). I do very little sharpening on my images, and usually find myself doing the most sharpening on architecture, where clean, well-defined edges are truly necesary.

My point is that, while judicious sharpening is useful, as you suggest, the problem with many images may lie in the image capture technique far more than in the post-processing. From what I have seen here on this site, I would recommend technique changes to many photographers before I would stress sharpening.

However, you do make a good point that sharpening--along with other "corrective" tools to make a photo more accurately mirror the real scene--are worth learning. I agree that sharpening should at least be considered with each image. Maybe someone can write a sharpening tutorial and post it on TrekEarth, for the edification of members.

ginabena
12-06-2002, 04:44 AM
Maybe some people like their photo's the way they are.

adam
12-06-2002, 05:45 AM
I think sharpening is very important to the post-processing process. The reason is that both digital cameras and slide/neg scanners have little/no sharpening internally which is a good thing. Scans and digital camera images are left soft on purpose so the photographer can then refine the image by applying the amount of sharpness they desire.

Another reason that sharpening is so important is due to image resizing. My slide scans are over 2000 pixels in length. If I then shrink the image to 600 pixels, the image will become blurrier. Therefore it's necessary to sharpen just to get back to the sharpness from the original scan.

You are right that it's necessary for the actually image itself to be sharp. No amount of 'unsharp mask' will fix the problem of a blurry photo. But using 'unsharp mask' is almost always necessary due to the way scanners and digital cameras create soft digital images. It's just a question of how much 'unsharp mask' to use. Some photos will need more than others.

BobTrips
12-06-2002, 06:30 AM
I think Adam has covered my concern fairly thoroughly. Reducing a file to the size used here will generally produce a picture that doesn't have the sharpness/detail that was present in the original. (Some reduction programs seem to take care of this during downsizing.)

To bring that original sharpness back to the picture generally takes one step past simple reduction.

I look at pictures on this site with "Photo Shop open (PSE)". When I see a picture that I like I copy it and open it in PSE. Then I play with the cropping/levels/sharpening to see if there is anything that improves it in my eyes. In doing so I learn a lot about why I liked that shot in the beginning.

I think people such as Sam can look at a shot and see slight color casts, etc. I need to check my eyes.

The most common thing I find is a really nice landscape that jumps to life when I sharpen it.

That's not to say that I think all pictures need/should be sharpened. Some are degraded by sharpening. Over sharpening will degrade almost any picture.

BTW, cost should not be a reason for not sharpening (or cropping, etc.).

If you're using Windows download a copy of Irfanview (www.irfranview.com). This is an excellent general purpose tool that I use almost daily for thumbnails, selecting, viewing, sorting, resizing, etc.

If you're using a Mac go to the Apple site and download their free editor.

adam
12-06-2002, 06:34 AM
I have major problems recognizing color casts. But I'm learning a lot by viewing Bob's visual critiques and reading other member critiques, especially Sam's.

Mrcurtain
12-18-2002, 09:52 PM
As for me... I'm learning. The workshop is awesome. Thanks guys.

Cheers,
-Adam (2)