This is the first time in my life that i heard that "improving contrast ...is part and parcel of sharpening" . Give me a break :sweat: Pls dun twist and turn yr way la.
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Portrait lens sigma 85mm f1.4 ex hsm or Canon 135mm f2.0
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This is the first time in my life that i heard that "improving contrast ...is part and parcel of sharpening" . Give me a break :sweat: Pls dun twist and turn yr way la.
Then u have to start relearning. Adjusting contrast is part of Post Processing , NOT Sharpening.
Repeat this 100 times everyday :bsmilie:
Adjusting anything after the picture has been taken is post-processing.
Sharpness is a product of resolution and contrast.
http://www.luminous-landscape.com/tutorials/understanding-series/lens-contrast.shtml
long article. where does it say so ? and u believe everythg stated in luminous landscape as gospel truth ?
If u do not believe anything on the internet to be the truth, then why are u using it to debate ? aren't u shooting yourself in the foot ?
Actually, it is true, however, we often take the term sharpness and resolution very loosely.
Sharpness, is actually the visual acuity appeal of the picture. Its more of the "feel" to the eyes. Its contributed by resolution and contrast.
The reason why images look sharp is because the edge is seen as darker, while the surface is seen as lighter. This is in fact contrast.
Resolution would refer to how fine that edge is, the ability of your lens/sensor to pick up small detail contributing to this fineness.
In fact, as a psychology student, I can tell you that your eyes has this same mechanism of sharpening. I cant remember the term for it now. But the light receptors in our eyes alternate in their responses when viewing borders to provide less activity at the borders, and more activity at the adjecent cells, resulting in stronger contrasts at the borders. That is one thing that makes our vision sharp. It also contributes to illusions sometimes, thats why we see weird grey areas when viewing small strips of black and white lines.
Sharpness, is actually the visual acuity appeal of the picture. Its more of the "feel" to the eyes. Its contributed by resolution and contrast.
The reason why images look sharp is because the edge is seen as darker, while the surface is seen as lighter. This is in fact contrast.
Resolution would refer to how fine that edge is, the ability of your lens/sensor to pick up small detail contributing to this fineness.
In fact, as a psychology student, I can tell you that your eyes has this same mechanism of sharpening. I cant remember the term for it now. But the light receptors in our eyes alternate in their responses when viewing borders to provide less activity at the borders, and more activity at the adjecent cells, resulting in stronger contrasts at the borders. That is one thing that makes our vision sharp. It also contributes to illusions sometimes, thats why we see weird grey areas when viewing small strips of black and white lines.
If u do not believe anything on the internet to be the truth, then why are u using it to debate ? aren't u shooting yourself in the foot ?
I'm sorry, I meant everything, not anything.
I may be wrong but I believe when we want the edge to be seen darker while the surface is lighter ,we achieved this by unsharp mask. The contrast of the body of the pic itself is adjusted via other tools like levelling , contrast etc.
I understand where you're coming from.
But essentially, making one part darker while adjacent parts lighter is essentially contrasting. You may have just selectively adjusted it to the edges as photoshop identifies them for you.
Whereas, what most people refer to as sharpness is resolution. That is infact how fine the details are. Usually most of it is contributed by your lens and sensor. It can be further simulated by unsharp mask as well (you notice it becomes grainier).
When you use unsharp mask or (whats the other one? smart unsharp mask?), you both increase resolution and contrast. Try pushing all your sliders to the maximum, you'll realize you get a super over-contrasty picture (some recognize it as an effect).
This is just a more technical way of presenting it.
Yes most people still refer to sharpness as purely resolution, and contrast as a totally separate thing. I'm just telling you the complete picture. =)
On sidenote, I use unsharp mask to improve contrast, only seldom sharpen. Try putting it to 250 pixels and 10% strength. You'll see that its largely contrast only, yet the picture looks way sharper.
I have not read the previous post so this is based on my personal exp. I have or owned before both the sigma 85 1.4, canon 85L, 135L and 85 1.8. What I can say is that sigma 85 is awesome. It's sharp, light, color is great and most importantly fast to focus. It's also cheap. I love it so much that I sold my 85L. The 135l is sharp too but it's alittle too tele for my usage(weddings) even when I'm using on a 5D. For crop, I would recommend the 85. My Frend just brought his sigma 85 in HK for less than 1k. A very good deal.
I stayed away to let others come in. Although I started learning about photography as a trainee teacher in 1964, I am still learning. But I don't need to do silly things like you suggested. Cheers.
I have noticed that you have tried to make fun of some of my quotations in other thread as well. I have not responded to those because I would have stooped to your level. I am a grown up and I believe in approaching argument with facts and do it with humility.
Nope, for this, I don't need to as you should know whether I spoke the truth. I will not respond to you any more.
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