I'm new to NPN, and I have found that learning to use the PP SW has been one of my biggest challenges. I recently posted an image that I thought was sharp, but upon further evaluation, I realized that it was not as sharp as I thought. My process is to open the RAW image in ACR, select 100% and closely look at the image. I guess I don't know how to evaluate the sharpness of the image. Can anyone give me some suggestions?
I'm guessing it was the tanager image in avian that you're referring to.
As a general guideline, the eye of a wildlife subject should be the point of focus. The human brain is hard wired to lock onto another animals eyes. Whether it's a wolf, bear, bird or bug, we feel a need to see their eyes, probably to gauge their intent. When I photograph wildlife, I always try to put the focus point on the area of the eyes. If the eye is tack sharp, a lot else can be forgiven.
So when reviewing files, I can go to 100% on the eye and quickly determine if it's a keeper worthy of further review.
In your tanager image, there are areas in the frame (some of the leaves for example) that are definitely sharper than the head. This says the point of focus was somewhere other than the head of the bird.
Again this is a general guideline and not carved in stone. There are many cases where this will not apply, but for most cases when wildlife is the primary subject, it's a good place to start.
It appears that the problem is that you're applying sharpening to your full size file. If you are displaying on the web you need to downsize your file first and then sharpen to taste. When you downsize a 10mpixel image to 720x480 pixels (for example) you are losing approximately 97% of the original pixels. Needless to say that demolishes your edges and details so you need the sharpening process to redefine those edges after downsizing.
It it is any consolation, I still occasionally screw up sharpening for web presentation. If it is any further consolation, I usually screw up sharpening for printing as well. I suggest you take the advice offered above, but, in any case, continue to post images. I appreciate and strive for technical perfection, but true satisfaction comes from a great composition.
I can't help but repeat myself but once again, "WOW". The quality of information on this forum is outstanding. I learn everyday. The article on sharpening and focus was just what I needed to read and understand. Thank you forum members!
Funny, there used to be an article on NPN with Sharpening tips but it seems to be gone. Here is Marc's and David Bostock's, two good techniques:
Sharpening for the Web—Marc Adamus
- Take full res image and reduce size to between 1000 and 1300 pixels. As much as 1300 for detailed forest scenes and such, 1000 for rock and more simple images. Apply "Sharpen" filter (easy enough right?) twice or even three times at 1300-1600 pixels.
- This will create a very oversharpened, noisy, mid-size image.
- Futher reduce image size to your web preference, such as 600 or 700 pixels.
- When reduced, this "tricks" Photoshop into applying an ultra-fine USM that you simply cannot acheive through other methods and all with maybe a 5-10% increase in file size vs. traditional methods such as regular USM or PK sharpener - which is rarely a problem.
- Play around with this technique and make it work for you. Every image is different. Sometimes I'll apply a sharpen filter 3 times at 1500 pixels and then reduce for an even finer sharpness, but other times it has too much of an adverse effect on color and resaturation is necessary. Sometimes I'll just lasso an area and apply the filter more heavily in one section before reducing size. Just experiment!
- Last, keep in mind not to sharpen skies too much as this will unecessarily increase file size. Do local touch-ups with 'sharp brush' to improve textures/definition in sky and water!
Sharpening Tip—David Bostock
One trick to sharpening I like to use is this: Whether I use USM, NIK, or some other technique, once I sharpen, right after, I select Edit, Fade...from the menu. This brings up a dialog with Opacity and Mode options. I generally leave Opacity alone, but change the mode to "Luminosity."
This accomplishes the same thing as changing the image mode to LAB Color and then sharpening the Lightness channel, but without going through the conversion process. I find it significantly reduces the halo effect.
BTW, since all images get softened due to the process of capturing and digitizing light, it's good practice to apply a mild sharpening right off the bat to restore what was lost in the actual capture process. Then you can later sharpen for web or inkjet print or offset or whatever output need you have. On my 5D Mark II, I start with Unsharp Mask at 110%, .7 Radius, 0 Threshold, but YMMV. That restores what was lost during the actual capture. Cartier-Bresson was correct for film; electronics change everything.
BTW, if anyone wants to read a book on the subject that goes way deep into the whole science behind it, get Real World Sharpening by Jeff Schewe and the late Bruce Fraser. But honestly, the articles provided by Jim DeWitt and others do cover most of the gamut.
Discussion
11 repliesI'm guessing it was the tanager image in avian that you're referring to.
As a general guideline, the eye of a wildlife subject should be the point of focus. The human brain is hard wired to lock onto another animals eyes. Whether it's a wolf, bear, bird or bug, we feel a need to see their eyes, probably to gauge their intent. When I photograph wildlife, I always try to put the focus point on the area of the eyes. If the eye is tack sharp, a lot else can be forgiven.
So when reviewing files, I can go to 100% on the eye and quickly determine if it's a keeper worthy of further review.
In your tanager image, there are areas in the frame (some of the leaves for example) that are definitely sharper than the head. This says the point of focus was somewhere other than the head of the bird.
Again this is a general guideline and not carved in stone. There are many cases where this will not apply, but for most cases when wildlife is the primary subject, it's a good place to start.
Best regards,,,,,David
It appears that the problem is that you're applying sharpening to your full size file. If you are displaying on the web you need to downsize your file first and then sharpen to taste. When you downsize a 10mpixel image to 720x480 pixels (for example) you are losing approximately 97% of the original pixels. Needless to say that demolishes your edges and details so you need the sharpening process to redefine those edges after downsizing.
Hope that helps,
Gary
Pete D.
--P
BTW, if anyone wants to read a book on the subject that goes way deep into the whole science behind it, get Real World Sharpening by Jeff Schewe and the late Bruce Fraser. But honestly, the articles provided by Jim DeWitt and others do cover most of the gamut.