12-07-2011, 05:50 PM
Hi Frank,
[quote name='Frank' timestamp='1323264725' post='13506']
Hi Wim:
Thank you very much for your educational posts (including the previous one), they are very helpful to me and I indeed learnt a lot from them. I think my problem is that although I know what is DOF but I cannot handle it well in practice. Perhaps I need more practice and more thinking. I often feel frustrated with a (U)WA lens without a DOF scale since I do not have good feelings of the DOF and sometimes I think a prime (U)WA with a DOF scale may be useful to me since with it I will be able to get some feelings about the DOF (a DoF scale will at least provide me with some reference). This is also one of the reasons that I asked about the Zeiss 21mm f2.8. Without a prime lens, a DOF calculator may also be helpful (at least for photography beginners, I think).[/quote]
It may indeed be helpful.
I do suggest you don't use hyperfocal distance DoF focusing, however, because the sharpness distribution with digital makes that an illusion IMO. You could read Harold Merklinger's article on DoF and focus: [url="http://www.trenholm.org/hmmerk/DOFR.html"]http://www.trenholm....mmerk/DOFR.html[/url]
Because of the way digital works, I'd suggest you make one important change, however: focus about 1/3 into the main subject in your frame, so that at least the main subject will be sharp in focus. By this I mean, if you are doing a landscape with, e.g., a beautiful barn as the eye catcher, focus 1/3 of the distance from the closest point of the barn to the furthest point of the barn into the barn. Use, e.g., the roof line in that case, so focus at 1/3 of the roofline, 1/3 from the camera side that is, therefore 1/3 being in front of the point focused on, and 2/3 behind. Making sure the most important point, the main subject, in your photograph is sharp, somehow makes the entire image look a lot sharper. And in addition, it also provides the so sought after and elusive "pop" <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='
' />.
Or select a specific range for a particular DoF, embracing the important stuff. Essentially, look at what attracts the eye, and make sure that that is sharp. Everything else can be dealt with in postprocessing, especially if you shot (U)WA at F/8 or F/11 <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='' />. Do select a slightly smaller CoC for Dof calculations, if you can, however, like 0.025 mm for FF (officially 0.03 mm), and 0.017 mm for APS-C (officially 0.0195 mm), to reflect better the pixel peeping we all do <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='' />.
Just experiment a little with different apertures and focusing distances when you next have a chance.
Even USM sharpening will do a great job - I normally use edge sharpening only for relatively extreme cases, like some of the trees in the background in my own picture and yours, and go easy on the slider <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='' />. Generally I use selective sharpening most of the time, or a little USM plus selective sharpening for certain details. I've used Topaz Vivacity (option: Clean) for the edge sharpening here, but there is a replacement for it that will do the same, for this specific type of sharpening anyway, namely Topaz Clean 3, the Edges option. The technique this uses is borrowed from NASA image processing algorithms <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='' />. Be careful, because it can easily be overdone, although that may look quite artsy if not done too often. Essentially, it will require some experimentation first. BTW, Topaz plugins for LightRoom and Photoshop can be used for a month for free, and those are completely working versions.
Thank you kindly!
Kindest regards, Wim
[quote name='Frank' timestamp='1323264725' post='13506']
Hi Wim:
Thank you very much for your educational posts (including the previous one), they are very helpful to me and I indeed learnt a lot from them. I think my problem is that although I know what is DOF but I cannot handle it well in practice. Perhaps I need more practice and more thinking. I often feel frustrated with a (U)WA lens without a DOF scale since I do not have good feelings of the DOF and sometimes I think a prime (U)WA with a DOF scale may be useful to me since with it I will be able to get some feelings about the DOF (a DoF scale will at least provide me with some reference). This is also one of the reasons that I asked about the Zeiss 21mm f2.8. Without a prime lens, a DOF calculator may also be helpful (at least for photography beginners, I think).[/quote]
It may indeed be helpful.
I do suggest you don't use hyperfocal distance DoF focusing, however, because the sharpness distribution with digital makes that an illusion IMO. You could read Harold Merklinger's article on DoF and focus: [url="http://www.trenholm.org/hmmerk/DOFR.html"]http://www.trenholm....mmerk/DOFR.html[/url]
Because of the way digital works, I'd suggest you make one important change, however: focus about 1/3 into the main subject in your frame, so that at least the main subject will be sharp in focus. By this I mean, if you are doing a landscape with, e.g., a beautiful barn as the eye catcher, focus 1/3 of the distance from the closest point of the barn to the furthest point of the barn into the barn. Use, e.g., the roof line in that case, so focus at 1/3 of the roofline, 1/3 from the camera side that is, therefore 1/3 being in front of the point focused on, and 2/3 behind. Making sure the most important point, the main subject, in your photograph is sharp, somehow makes the entire image look a lot sharper. And in addition, it also provides the so sought after and elusive "pop" <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='
' />.Or select a specific range for a particular DoF, embracing the important stuff. Essentially, look at what attracts the eye, and make sure that that is sharp. Everything else can be dealt with in postprocessing, especially if you shot (U)WA at F/8 or F/11 <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='
' />. Do select a slightly smaller CoC for Dof calculations, if you can, however, like 0.025 mm for FF (officially 0.03 mm), and 0.017 mm for APS-C (officially 0.0195 mm), to reflect better the pixel peeping we all do <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='' />.Just experiment a little with different apertures and focusing distances when you next have a chance.
Quote:The edge sharpening technique looks cool. I did not know it but I know it now. I should learn to use it.
Even USM sharpening will do a great job - I normally use edge sharpening only for relatively extreme cases, like some of the trees in the background in my own picture and yours, and go easy on the slider <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='
' />. Generally I use selective sharpening most of the time, or a little USM plus selective sharpening for certain details. I've used Topaz Vivacity (option: Clean) for the edge sharpening here, but there is a replacement for it that will do the same, for this specific type of sharpening anyway, namely Topaz Clean 3, the Edges option. The technique this uses is borrowed from NASA image processing algorithms <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='' />. Be careful, because it can easily be overdone, although that may look quite artsy if not done too often. Essentially, it will require some experimentation first. BTW, Topaz plugins for LightRoom and Photoshop can be used for a month for free, and those are completely working versions.Quote:Thank you also for the praising words on my picture.
BTW, I don't mind you did edge sharpening to my picture. Indeed I am grateful to you for educating me with my picture.
With best regards,
Frank
Thank you kindly!
Kindest regards, Wim
Gear: Canon EOS R with 3 primes and 2 zooms, 4 EF-R adapters, Canon EOS 5 (analog), 9 Canon EF primes, a lone Canon EF zoom, 2 extenders, 2 converters, tubes; Olympus OM-D 1 Mk II & Pen F with 12 primes, 6 zooms, and 3 Metabones EF-MFT adapters ....