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Old Jan 23, 2006, 5:37 PM   #11
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Thanks Dustin, you're always so helpful and "spot on"!

Lizabeth, hope that this info might be as much use to you as I trust it will be to me...

I'll really try to play around with the suggestions you made Dustin, and try to see what works best. I didn't realise till now that many DSLR made photos also need so much unsharp mask post processing! I guess it shows I'm a person who is still making the transition from P&S to DSLR... and still climbing the learning curve!

Thanks again Dustin for the advice / help. You really explained it well. After your PhD in biomechanics... will you continue to do one in photomechanincs and explanation? I think you've got potential there as well! And all the best lizabeth with your sharpness too...

Paul
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Old Jan 23, 2006, 6:00 PM   #12
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Regarding why it is called an unsharp mask, I asked the guy I have been buying my cameras and lenses from (another reason to buy from a local, camera shop, not just the big box stores or on-line - you can stand there and ask all sorts of questions and get answers when you need them if you support their business.)

He explained it is an old dark room technique where they make a slightly more out of focus negative (ie an unsharp mask), physically layer it over the original negative, then make a print by putting both through the enlarger simultaneously. Apparently this technique would sharpen the image. I have no idea if the USM feature in PS uses the same principle or whether the name is simply an artifact from the first versions of PS which I imagine were targetted to the pro photographers who were making the transition to digital. I guess keeping the terms consistent with dark room techniques made it less confusing as opposed to those of us who have never done any real darkroom work.

Kevin
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Old Jan 23, 2006, 6:06 PM   #13
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klfatcj wrote:
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Regarding why it is called an unsharp mask, I asked the guy I have been buying my cameras and lenses from (another reason to buy from a local, camera shop, not just the big box stores or on-line - you can stand there and ask all sorts of questions and get answers when you need them if you support their business.)

He explained it is an old dark room technique where they make a slightly more out of focus negative (ie an unsharp mask), physically layer it over the original negative, then make a print by putting both through the enlarger simultaneously. Apparently this technique would sharpen the image. I have no idea if the USM feature in PS uses the same principle or whether the name is simply an artifact from the first versions of PS which I imagine were targetted to the pro photographers who were making the transition to digital. I guess keeping the terms consistent with dark room techniques made it less confusing as opposed to those of us who have never done any real darkroom work.

Kevin

that would make sense since they also kept other terms similar.. i.e. dodging and burning.. etc..
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Old Jan 23, 2006, 8:18 PM   #14
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Thank you everybody for the great suggestions. I will try a higher f-stop next time out. Paul, great question, one I have wondered myself & didn't quite understand. Dustin, thank you foranswering our questions...I have learned alot by just tuning in and listening. I will experiment as well with PS.
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Old Jan 24, 2006, 2:04 AM   #15
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Not much to say but have learnt from Dustin's explanation. Did not know that the bigger the print the bgger the parameters of unmasking. Regards Jaki.

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Old Jan 24, 2006, 4:05 AM   #16
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It's not super sharp, could be for a variety of reasons.

Even though 1/200 would seem to be ok for 130mm * 1.5 = 195 is still only rule-of-thumb. If handholding you might be better off with a faster shutter speed or a tripod/monopod.

Secondly the bird itself could be moving somewhat, so a faster shutter speed would help there too.

Thirdly you may well not be processing the image optimally. Are you shooting RAW or using in-camara JPG? Are you using Photoshop? Which version? If you are using CS/
CS2 and you want excellent sharpening without the hassle check out these links:

http://www.luminous-landscape.com/re...harpener.shtml

http://www.pixelgenius.com/sharpener/

Well worth the price IMO.

Fourthly, using a smaller aperture like f8 or f11 might help, for reasons of DOF and also because your lens will be better stopped down.

And finally yes, it may well be that your lens is incapable of the resolution you are hoping for. The Sigma 100-300 f4 is probably the sharpest telephoto zoom ever made and would be a very sound investment if you like taking photos of birds.

What camera are you using by the way?
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Old Jan 24, 2006, 6:54 PM   #17
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peripatetic wrote:
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And finally yes, it may well be that your lens is incapable of the resolution you are hoping for. The Sigma 100-300 f4 is probably the sharpest telephoto zoom ever made and would be a very sound investment if you like taking photos of birds.

i agree 110%.. that sigma 100-300 f4 is SHARP
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Old Jan 24, 2006, 7:22 PM   #18
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Peripatetic,

I have the RebelXT and use a tripod & a remote switch. I shoot using in-camera jpeg only. I have Photoshop elements 2, & up until this thread I didn't know alot about sharpening. I used the sharpening tool...not usm. So re-processing the same pic I see thatusing usm makes abig difference in thesharpness of the pic. (Lots more possibilities ) This weekend I will try using a higher f-stop, & then do pp using usm. I haven't shot raw yet because my version of ps does not have the ability to process raw. I believe the program that came with my camera ( digital photo professional ) has that ability, so I will experiment in rawalso. You guys have given mealot of new things to try & I thank you all for that. Look for my picnext week. :-)

Kath
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Old Jan 24, 2006, 8:37 PM   #19
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Yah, I'd say 1/250th and you'd be rocking.

You'd be shooting wide open, but that's cool 'cause it would blur the background even more.

-- Terry
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