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Old 10-15-2009, 03:47 PM
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Wandering_Dan Wandering_Dan is offline
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Default To jhm: F/16 is not necessarily sharper

Hi, John -

One thing I've learned - painfully - is that while higher (numerically) f-stops give greater DOF, they don't necessarily make a sharper photo. Each lens (and it seems even more so for zoom lenses) has a "sweetspot" where it is sharpest, usually somewhere in the middle of its range (there's argument about that point). In a shot like this, where the focus is already at infinity, I've found that - within limits - the f/stop is not as critical. However, your comment has moved me to make some more tests on the lenses I'm taking to Paris this weekend, to make sure I have their sweet spots accurately.

Another factor in sharpness has to do with shooting in RAW; here, the camera does no sharpening, and in fact the RAW capture (at least in Nikon) is deliberately a little unsharpened. I've never quite understood the logic behind that, but the claim is that Nikon expects the photographer to do his own sharpening in PP. Adobe's Camera Raw program (invoked whenever I open an NEF file) automatically sharpens by 25%; for many shots it should really be around 100%, but sometimes I forget to do that. Something else I have to keep reminding myself about.

Your thoughts?

Best,
Dan
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Old 10-16-2009, 04:28 PM
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jhm jhm is offline
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Default Re: To jhm: F/16 is not necessarily sharper

Hi Dan,

I understand you very well, RAW, JPEG and different cameras.
I am not known to Nikon, not as digital camera, formerly I use Nikon, now Canon, this are two different cameras and different lenses.
The discussions between F/ shall always remain exist.
I think that Nikon a better camera is in JEPG than Canon.
I work always with Canon DPP of RAW to JPEG, I have to continuously give a little bit more sharpness, approximately 8%.
I have tried to make a WS of your picture, your picture is very well.
I hope that you these WS can appreciate
When you have problem with my English, write again to my!

Have a nice weekend,

John
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Old 10-16-2009, 05:10 PM
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Wandering_Dan Wandering_Dan is offline
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Default Re: To jhm: F/16 is not necessarily sharper

Hi. John -

Thanks for the workshop. I appreciate it if only for the different perspective on sharpness; what others see as correctly sharp I sometimes I see as oversharpened. (For me, the true test is in the printing, but I can't display that on a computer screen.) It's becoming clearer that I will have to get a new monitor soon. I'm holding off for the moment because circumstances may dictate my getting a whole new computer, and I need to wait until that is settled.

In the meantime, to continue the sweetspot discussion: I ran a set of tests on my lenses yesterday, using the same image in the same position. I found that:

My 18-70 lens has its "sweetspot" around f/11.
My 18-200 VR lens is best around f/13 to f/14.
However (and this is the annoying part), my 18-70 kit lens is sharper at its sharpest than my fancier, more expensive 18-200 lens. Arrrghh! (An untranslatable but highly evocative word.)

(One caveat: Lenses have more individual variation than they really should. Someone else's Nikon 18-200 may be better.)

As for Nikon vs. Canon, my feeling has always been that the two are approximately equal, and choosing between them is for me a matter of which one I am more comfortable with. In my case, it's Nikon. I long ago stopped shooting in JPG (except when required for a workshop), because I would rather adjust the image myself later on than have the camera do it. Also, when the camera does it, there's no going back to the original image.

And I understand your English well enough. Sorry that I do not speak Dutch (when I was working in The Hague in 1992 I learned the difference in pronunciation between "oud" and "uit" but I couldn't do it now.)

Best,
Dan

PS: We leave for Paris early tomorrow morning, and while there my communication with TE will be limited.
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Old 10-16-2009, 06:12 PM
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jhm jhm is offline
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Default Re: To jhm: F/16 is not necessarily sharper

Hi Dan,

I have this same problem, the different lenses are indeed something different.
My 70-200 one of the best lenses of Canon is very difficult for a good picture, my 16-35 super wide angle is a lot better, you can see that I every day learn, I look for everyday for make a better picture.
I am 68 year old and have to still a lot learn, I makes pictures since my 15th year.
Dutch is a very difficult language for learn, when you my understands is very pleasant for me.

I wish you and your family a pleasant travel to Paris, a lovely city for photographers and also a pleasant evening with a good glass wine.

Later I come back for your work in Netherland The Hague.

Greetings from Belgium, a neighbour of France,

John
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