Re: How much difference does optimizing the aperture make?
On 5/6/12, Mark Roberts, discombobulated, unleashed: What would be cool would be an ND filter that went behind the reflex mirror and in front of the sensor. My video camera has three NDs on a wheel exactly in that place. -- Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche -- http://www.cottysnaps.com _ -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: How much difference does optimizing the aperture make?
Lens makers used to give this number. My Zeiss lenses generally claimed to be best at 5.6, and this is now my default setting even though I no longer have any Zeiss lenses. The theory was you set the lens on 5.6, or whatever, and used the hyperfocal distance to get the sharpest photo with the most depth-of-field. Some of the Pentax cameras had a setting which automatically set the lens at its best aperture, which was coded into the chip, I suppose, when it might have been cheaper just to paint that aperture mark a different colour. B -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Larry Colen Sent: 04 June 2012 23:22 To: Pentax-Discuss Mail List Subject: How much difference does optimizing the aperture make? I was thinking about my quest for sharpness, and was considering trying to do some research into what the aperture sweet spot is for each lens, and was wondering if anyone had already made a chart of them. Then I wondered how much it really matters. I've heard a couple of stops down from wide open, anywhere between f/8 and f/16, and a couple other rules of thumb. I do know that on some lenses, particularly the FA50/1.4, that stopping it down a couple of stops from wide open, makes a huge difference. And I suspect that if you look on an MTF chart, you might be able to easily see the difference between f/4 and f/8, but is there a practical noticeable difference? There is also the question of sharpness at the critical focus distance, and overall sharpness. That a lens might be sharper at f/4 than f/16 at the focal distance, but with a lot more depth of field, more of the photo will be sharper at f/16, than at f/64. I'm primarily interested in answers based on personal, practical experience, rather than theory. My hunch is that as long as I'm not too close to wide open, or pushing diffraction limits, optimizing aperture for sharpness is not the most productive place to spend my time and energy. That I'm generally best optimizing the aperture for the picture, and not trying to optimize the aperture for MTF. -- Larry Colen l...@red4est.com sent from i4est -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
On Jun 4, 2012, at 17:31 , J.C. O'Connell wrote: In theory a perfect lens would be sharpest wide open, so a really good lens would be sharpest close to wide open. If it takes 4 or 5 stops to sharpen up a lens, its probably not that great. As for good rules of thumb, I find f5.6 or f8 to usually work pretty damn good If a kens is designed to be at it's optimum wide open and becomes less sharp as you stop down - why bother with an aperture at all?DOF?? - use another lens. Joseph McAllister Pentaxian -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
Just remember - while all of this is mildly interesting, it doesn't really make a lot of difference to the end result. When you're looking at the photograph on a screen or paper, the tiny differences are extremely hard to see. If the differences in f-stops are that distinct in a modern lens, you probably need to be looking for a different lens. And if you're looking at the sharpness, you probably don't have a very good photo to start with. gs George Sinos gsi...@gmail.com www.georgesphotos.net plus.georgesinos.com On Tue, Jun 5, 2012 at 2:42 AM, Joseph McAllister pentax...@mac.com wrote: On Jun 4, 2012, at 17:31 , J.C. O'Connell wrote: In theory a perfect lens would be sharpest wide open, so a really good lens would be sharpest close to wide open. If it takes 4 or 5 stops to sharpen up a lens, its probably not that great. As for good rules of thumb, I find f5.6 or f8 to usually work pretty damn good If a kens is designed to be at it's optimum wide open and becomes less sharp as you stop down - why bother with an aperture at all? DOF?? - use another lens. Joseph McAllister Pentaxian -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
Larry Colen wrote: I was thinking about my quest for sharpness, and was considering trying to do some research into what the aperture sweet spot is for each lens, and was wondering if anyone had already made a chart of them. The sweet spot for sharpness is usually around f/5.6-f/8, depending on the lens. Of course, depending on the lens and the composition of your photo you might need more depth of field than the optimum aperture yields, so sharpness and DOF is usually a compromise. (Also, sharpness and shutter speed can be a trade-off too if you're trying to get motion blur from long shutter speed. I run into this problem when shooting waterfalls and such and I'm forced to stop way down to f/22 - another reason I'm wishing for a DSLR with *lower* ISO settings.) With a Pentax camera and a Pentax lens it's easy to find the sharpest aperture: Just set the camera's Program exposure line into MTF mode and use Program auto exposure: the camera will read the MTF data that's written into the chip in the lens and set the aperture to the optimum value for that lens. I don't know of any other camera maker that offers this feature. -- Mark Roberts - Photography Multimedia www.robertstech.com -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: How much difference does optimizing the aperture make?
Less than actually getting the subject in focus does. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: How much difference does optimizing the aperture make?
From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Mark Roberts (Also, sharpness and shutter speed can be a trade-off too if you're trying to get motion blur from long shutter speed. I run into this problem when shooting waterfalls and such and I'm forced to stop way down to f/22 - another reason I'm wishing for a DSLR with *lower* ISO settings.) ND filters B -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
On 6 June 2012 00:10, Bob W p...@web-options.com wrote: From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Mark Roberts (Also, sharpness and shutter speed can be a trade-off too if you're trying to get motion blur from long shutter speed. I run into this problem when shooting waterfalls and such and I'm forced to stop way down to f/22 - another reason I'm wishing for a DSLR with *lower* ISO settings.) ND filters And/or in camera multiple exposures. DS -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
Bob W wrote: From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Mark Roberts (Also, sharpness and shutter speed can be a trade-off too if you're trying to get motion blur from long shutter speed. I run into this problem when shooting waterfalls and such and I'm forced to stop way down to f/22 - another reason I'm wishing for a DSLR with *lower* ISO settings.) ND filters ...are a pain in the arse. Dark viewfinders suck. Composing, focusing and then attaching the ND filter also sucks. What would be cool would be an ND filter that went behind the reflex mirror and in front of the sensor. -- Mark Roberts - Photography Multimedia www.robertstech.com -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: How much difference does optimizing the aperture make?
From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Mark Roberts Bob W wrote: From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Mark Roberts (Also, sharpness and shutter speed can be a trade- off too if you're trying to get motion blur from long shutter speed. I run into this problem when shooting waterfalls and such and I'm forced to stop way down to f/22 - another reason I'm wishing for a DSLR with *lower* ISO settings.) ND filters ...are a pain in the arse. Dark viewfinders suck. Composing, focusing and then attaching the ND filter also sucks. What would be cool would be an ND filter that went behind the reflex mirror and in front of the sensor. drop-in ones are a lot easier to use than screw-mounted ones. If you're shooting blurry waterfalls then your camera is on a tripod or similar so you can compose and focus, then drop the filter in without disturbing anything. It also makes you look from a distance as if you're using a dark slide, so people will think you're a proper photographer. B -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
Also a factor, the longer the lens, the narrower the depth of field at the same f stop on a shorter lens. -Original Message- From: Mark Roberts postmas...@robertstech.com Sent: Jun 5, 2012 9:27 AM To: Pentax-Discuss Mail List pdml@pdml.net Subject: Re: How much difference does optimizing the aperture make? Larry Colen wrote: I was thinking about my quest for sharpness, and was considering trying to do some research into what the aperture sweet spot is for each lens, and was wondering if anyone had already made a chart of them. The sweet spot for sharpness is usually around f/5.6-f/8, depending on the lens. Of course, depending on the lens and the composition of your photo you might need more depth of field than the optimum aperture yields, so sharpness and DOF is usually a compromise. (Also, sharpness and shutter speed can be a trade-off too if you're trying to get motion blur from long shutter speed. I run into this problem when shooting waterfalls and such and I'm forced to stop way down to f/22 - another reason I'm wishing for a DSLR with *lower* ISO settings.) With a Pentax camera and a Pentax lens it's easy to find the sharpest aperture: Just set the camera's Program exposure line into MTF mode and use Program auto exposure: the camera will read the MTF data that's written into the chip in the lens and set the aperture to the optimum value for that lens. I don't know of any other camera maker that offers this feature. -- Mark Roberts - Photography Multimedia www.robertstech.com -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
re: diffraction vs DOF Please see Charles Nam's most reasonable *comment* in response to the article on the following page: http://www.theatreofnoise.com/2011/06/choosing-optimal-aperture-to-avoid.html The problem with dealing in mathematical formula is that they are not Real World and do not take into account the other factors (and compromises) that go into the IQ you get. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: How much difference does optimizing the aperture make?
only at same subject to camera distance... - J.C.O'Connell hifis...@gate.net - -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Kenneth Waller Sent: Tuesday, June 05, 2012 4:12 PM To: Pentax-Discuss Mail List Subject: Re: How much difference does optimizing the aperture make? Also a factor, the longer the lens, the narrower the depth of field at the same f stop on a shorter lens. -Original Message- From: Mark Roberts postmas...@robertstech.com Sent: Jun 5, 2012 9:27 AM To: Pentax-Discuss Mail List pdml@pdml.net Subject: Re: How much difference does optimizing the aperture make? Larry Colen wrote: I was thinking about my quest for sharpness, and was considering trying to do some research into what the aperture sweet spot is for each lens, and was wondering if anyone had already made a chart of them. The sweet spot for sharpness is usually around f/5.6-f/8, depending on the lens. Of course, depending on the lens and the composition of your photo you might need more depth of field than the optimum aperture yields, so sharpness and DOF is usually a compromise. (Also, sharpness and shutter speed can be a trade-off too if you're trying to get motion blur from long shutter speed. I run into this problem when shooting waterfalls and such and I'm forced to stop way down to f/22 - another reason I'm wishing for a DSLR with *lower* ISO settings.) With a Pentax camera and a Pentax lens it's easy to find the sharpest aperture: Just set the camera's Program exposure line into MTF mode and use Program auto exposure: the camera will read the MTF data that's written into the chip in the lens and set the aperture to the optimum value for that lens. I don't know of any other camera maker that offers this feature. -- Mark Roberts - Photography Multimedia www.robertstech.com -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
How much difference does optimizing the aperture make?
I was thinking about my quest for sharpness, and was considering trying to do some research into what the aperture sweet spot is for each lens, and was wondering if anyone had already made a chart of them. Then I wondered how much it really matters. I've heard a couple of stops down from wide open, anywhere between f/8 and f/16, and a couple other rules of thumb. I do know that on some lenses, particularly the FA50/1.4, that stopping it down a couple of stops from wide open, makes a huge difference. And I suspect that if you look on an MTF chart, you might be able to easily see the difference between f/4 and f/8, but is there a practical noticeable difference? There is also the question of sharpness at the critical focus distance, and overall sharpness. That a lens might be sharper at f/4 than f/16 at the focal distance, but with a lot more depth of field, more of the photo will be sharper at f/16, than at f/64. I'm primarily interested in answers based on personal, practical experience, rather than theory. My hunch is that as long as I'm not too close to wide open, or pushing diffraction limits, optimizing aperture for sharpness is not the most productive place to spend my time and energy. That I'm generally best optimizing the aperture for the picture, and not trying to optimize the aperture for MTF. -- Larry Colen l...@red4est.com sent from i4est -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
On 2012-06-04 18:22, Larry Colen wrote: Then I wondered how much it really matters. I've heard a couple of stops down from wide open, anywhere between f/8 and f/16, and a couple other rules of thumb. I do know that on some lenses, particularly the FA50/1.4, that stopping it down a couple of stops from wide open, makes a huge difference. And I suspect that if you look on an MTF chart, you might be able to easily see the difference between f/4 and f/8, but is there a practical noticeable difference? There is also the question of sharpness at the critical focus distance, and overall sharpness. That a lens might be sharper at f/4 than f/16 at the focal distance, but with a lot more depth of field, more of the photo will be sharper at f/16, than at f/64. If you're using an F series or later lens, and you put the camera's auto program into MTF mode in the menus (it might be the default), it will base it's aperture selections on MTF data in the lens' on-board chip. This is at least Pentax' idea of the best aperture/shutter tradeoff for the particular lens. -- Doug Lefty Franklin NutDriver Racing http://NutDriver.org Facebook NutDriver Racing Sponsored by Murphy -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
On Mon, Jun 4, 2012 at 6:22 PM, Larry Colen l...@red4est.com wrote: optimizing aperture for sharpness is not the most productive place to spend my time and energy. Mark! Apologies for taking that out of context. :-) That I'm generally best optimizing the aperture for the picture, and not trying to optimize the aperture for MTF. Yes!! One of the best arguments for keeping one lens on your camera for a goodly time and really learning it, is so you can empirically determine your own personal subject-lens-camera-brain sweet spots. For example I've learned that f/2.0 on the DA*55 is a really sweet spot for beautiful portraits. I have never once pored over any MTF * charts for any Pentax lens, let alone the DA*55. But I've taken thousands of frames with it and analyzed and post-processed them until they hit my sweet spot for beauty. -- -bmw [*] or MTBF, or BMF -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
I never really spent too much time worrying about researching the sweet spot. I just chose the aperture that gave me the DoF I wanted. That said, with the D800's stupidly high resolution, it really pays to hit the sweet spot. DS On 5 June 2012 06:53, Bruce Walker bruce.wal...@gmail.com wrote: On Mon, Jun 4, 2012 at 6:22 PM, Larry Colen l...@red4est.com wrote: optimizing aperture for sharpness is not the most productive place to spend my time and energy. Mark! Apologies for taking that out of context. :-) That I'm generally best optimizing the aperture for the picture, and not trying to optimize the aperture for MTF. Yes!! One of the best arguments for keeping one lens on your camera for a goodly time and really learning it, is so you can empirically determine your own personal subject-lens-camera-brain sweet spots. For example I've learned that f/2.0 on the DA*55 is a really sweet spot for beautiful portraits. I have never once pored over any MTF * charts for any Pentax lens, let alone the DA*55. But I've taken thousands of frames with it and analyzed and post-processed them until they hit my sweet spot for beauty. -- -bmw [*] or MTBF, or BMF -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
If you can find the MTF charts for each lens, it will tell you all you need to know about what aperture it is sharpest at. On Mon, Jun 4, 2012 at 6:22 PM, Larry Colen l...@red4est.com wrote: I was thinking about my quest for sharpness, and was considering trying to do some research into what the aperture sweet spot is for each lens, and was wondering if anyone had already made a chart of them. Then I wondered how much it really matters. I've heard a couple of stops down from wide open, anywhere between f/8 and f/16, and a couple other rules of thumb. I do know that on some lenses, particularly the FA50/1.4, that stopping it down a couple of stops from wide open, makes a huge difference. And I suspect that if you look on an MTF chart, you might be able to easily see the difference between f/4 and f/8, but is there a practical noticeable difference? There is also the question of sharpness at the critical focus distance, and overall sharpness. That a lens might be sharper at f/4 than f/16 at the focal distance, but with a lot more depth of field, more of the photo will be sharper at f/16, than at f/64. I'm primarily interested in answers based on personal, practical experience, rather than theory. My hunch is that as long as I'm not too close to wide open, or pushing diffraction limits, optimizing aperture for sharpness is not the most productive place to spend my time and energy. That I'm generally best optimizing the aperture for the picture, and not trying to optimize the aperture for MTF. -- Larry Colen l...@red4est.com sent from i4est -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- David Parsons Photography http://www.davidparsonsphoto.com Aloha Photographer Photoblog http://alohaphotog.blogspot.com/ -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
How much difference does optimizing the aperture make?
Larry's ideas: I was thinking about my quest for sharpness, and was considering trying to do some research into what the aperture sweet spot is for each lens, and was wondering if anyone had already made a chart of them. Then I wondered how much it really matters. I've heard a couple of stops down from wide open, anywhere between f/8 and f/16, and a couple other rules of thumb. I do know that on some lenses, particularly the FA50/1.4, that stopping it down a couple of stops from wide open, makes a huge difference. And I suspect that if you look on an MTF chart, you might be able to easily see the difference between f/4 and f/8, but is there a practical noticeable difference? There is also the question of sharpness at the critical focus distance, and overall sharpness. That a lens might be sharper at f/4 than f/16 at the focal distance, but with a lot more depth of field, more of the photo will be sharper at f/16, than at f/64. I'm primarily interested in answers based on personal, practical experience, rather than theory. My hunch is that as long as I'm not too close to wide open, or pushing diffraction limits, optimizing aperture for sharpness is not the most productive place to spend my time and energy. That I'm generally best optimizing the aperture for the picture, and not trying to optimize the aperture for MTF. -- Larry Colen lrc at red4est.com sent from i4est Larry, I'd consider both sharpness and DOF when choosing the aperture for one particular pic. Manual focus, f/8 at 2m with the wide part of the 18~55 has given me the fastest AF in town. It also has improved sharpness across the frame. Using the fixed 50s I see a strong diff as I go from wide open to f/5.6 - but then I often want less focus on the background and accept less sharpness. My old SMC Takumar 135 f/2.5 is soft open and gets very sharp from 5.6 to 11. I checked MTF charts / pratical resolution tests of lenses, and did my own over the years. Some of my results did go against others, but all my lenses are softer wide open than at some other point, both in the tripod against some target and in the real world. Knowing what to expect at any particular setting is useful, IMHO. From memory, some lenses got sharp faster - close to wide open - and two in particular needed to be closed a lot to behave - an ancient Tokina 28-85 and Sigma's 24mm (first version). -- luiz felipe luiz.felipe at luizfelipe.fot.br -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
On 6/4/2012 6:22 PM, Larry Colen wrote: I was thinking about my quest for sharpness, and was considering trying to do some research into what the aperture sweet spot is for each lens, and was wondering if anyone had already made a chart of them. Then I wondered how much it really matters. I've heard a couple of stops down from wide open, anywhere between f/8 and f/16, and a couple other rules of thumb. I do know that on some lenses, particularly the FA50/1.4, that stopping it down a couple of stops from wide open, makes a huge difference. And I suspect that if you look on an MTF chart, you might be able to easily see the difference between f/4 and f/8, but is there a practical noticeable difference? There is also the question of sharpness at the critical focus distance, and overall sharpness. That a lens might be sharper at f/4 than f/16 at the focal distance, but with a lot more depth of field, more of the photo will be sharper at f/16, than at f/64. I'm primarily interested in answers based on personal, practical experience, rather than theory. My hunch is that as long as I'm not too close to wide open, or pushing diffraction limits, optimizing aperture for sharpness is not the most productive place to spend my time and energy. That I'm generally best optimizing the aperture for the picture, and not trying to optimize the aperture for MTF. -- Larry Colen l...@red4est.com sent from i4est To a large extent it depends on the lens - I've seen some that benefit hugely from being stopped down one or two stops and others that show less of an improvement. My A 50 1.4 benefits form being stopped down, my FA 50 1.7 is almost as good wide open as it is at f 4 or 5.6. Back when I had the Rikenon 55MM F1.2 it was noticeably less sharp wide open (and also had a fair bit of light fall off.) My Tokina 400 f5.6 is not so sharp at f5.6 but improves tremendously at f8. Most macro lenses I've tried benefit from stopping down but are very good wide open as well. What it boils down to (for me) - in theory any lens would benefit from stopping down one or two stops, but unless I see a difference I don't worry about it. Stopping down = slow shutter speed or higher ISO, either of which would probably offset the benefit gained by shooting at the optimum f stop. I do notice a loss of sharpness when stopping down to f16 or beyond, I assume due to diffraction. So, as a general rule of thumb I try to stick with f8 or at the most f11 . Makes for nicer backgrounds as well. For general shooting I find f5.6 to usually be fine for DOF. You really just got to try out your lenses and see what you experience. MCC -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
F/5.6 and be there. Sent from my iPad Jeffery L. Smith New Orleans, Louisiana USA On Jun 4, 2012, at 19:05, Mark C pdml-m...@charter.net wrote: On 6/4/2012 6:22 PM, Larry Colen wrote: I was thinking about my quest for sharpness, and was considering trying to do some research into what the aperture sweet spot is for each lens, and was wondering if anyone had already made a chart of them. Then I wondered how much it really matters. I've heard a couple of stops down from wide open, anywhere between f/8 and f/16, and a couple other rules of thumb. I do know that on some lenses, particularly the FA50/1.4, that stopping it down a couple of stops from wide open, makes a huge difference. And I suspect that if you look on an MTF chart, you might be able to easily see the difference between f/4 and f/8, but is there a practical noticeable difference? There is also the question of sharpness at the critical focus distance, and overall sharpness. That a lens might be sharper at f/4 than f/16 at the focal distance, but with a lot more depth of field, more of the photo will be sharper at f/16, than at f/64. I'm primarily interested in answers based on personal, practical experience, rather than theory. My hunch is that as long as I'm not too close to wide open, or pushing diffraction limits, optimizing aperture for sharpness is not the most productive place to spend my time and energy. That I'm generally best optimizing the aperture for the picture, and not trying to optimize the aperture for MTF. -- Larry Colen l...@red4est.com sent from i4est To a large extent it depends on the lens - I've seen some that benefit hugely from being stopped down one or two stops and others that show less of an improvement. My A 50 1.4 benefits form being stopped down, my FA 50 1.7 is almost as good wide open as it is at f 4 or 5.6. Back when I had the Rikenon 55MM F1.2 it was noticeably less sharp wide open (and also had a fair bit of light fall off.) My Tokina 400 f5.6 is not so sharp at f5.6 but improves tremendously at f8. Most macro lenses I've tried benefit from stopping down but are very good wide open as well. What it boils down to (for me) - in theory any lens would benefit from stopping down one or two stops, but unless I see a difference I don't worry about it. Stopping down = slow shutter speed or higher ISO, either of which would probably offset the benefit gained by shooting at the optimum f stop. I do notice a loss of sharpness when stopping down to f16 or beyond, I assume due to diffraction. So, as a general rule of thumb I try to stick with f8 or at the most f11 . Makes for nicer backgrounds as well. For general shooting I find f5.6 to usually be fine for DOF. You really just got to try out your lenses and see what you experience. MCC -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
RE: How much difference does optimizing the aperture make?
In theory a perfect lens would be sharpest wide open, so a really good lens would be sharpest close to wide open. If it takes 4 or 5 stops to sharpen up a lens, its probably not that great. As for good rules of thumb, I find f5.6 or f8 to usually work pretty damn good - J.C.O'Connell hifis...@gate.net - -Original Message- From: pdml-boun...@pdml.net [mailto:pdml-boun...@pdml.net] On Behalf Of Mark C Sent: Monday, June 04, 2012 8:06 PM To: Pentax-Discuss Mail List Subject: Re: How much difference does optimizing the aperture make? On 6/4/2012 6:22 PM, Larry Colen wrote: I was thinking about my quest for sharpness, and was considering trying to do some research into what the aperture sweet spot is for each lens, and was wondering if anyone had already made a chart of them. Then I wondered how much it really matters. I've heard a couple of stops down from wide open, anywhere between f/8 and f/16, and a couple other rules of thumb. I do know that on some lenses, particularly the FA50/1.4, that stopping it down a couple of stops from wide open, makes a huge difference. And I suspect that if you look on an MTF chart, you might be able to easily see the difference between f/4 and f/8, but is there a practical noticeable difference? There is also the question of sharpness at the critical focus distance, and overall sharpness. That a lens might be sharper at f/4 than f/16 at the focal distance, but with a lot more depth of field, more of the photo will be sharper at f/16, than at f/64. I'm primarily interested in answers based on personal, practical experience, rather than theory. My hunch is that as long as I'm not too close to wide open, or pushing diffraction limits, optimizing aperture for sharpness is not the most productive place to spend my time and energy. That I'm generally best optimizing the aperture for the picture, and not trying to optimize the aperture for MTF. -- Larry Colen l...@red4est.com sent from i4est To a large extent it depends on the lens - I've seen some that benefit hugely from being stopped down one or two stops and others that show less of an improvement. My A 50 1.4 benefits form being stopped down, my FA 50 1.7 is almost as good wide open as it is at f 4 or 5.6. Back when I had the Rikenon 55MM F1.2 it was noticeably less sharp wide open (and also had a fair bit of light fall off.) My Tokina 400 f5.6 is not so sharp at f5.6 but improves tremendously at f8. Most macro lenses I've tried benefit from stopping down but are very good wide open as well. What it boils down to (for me) - in theory any lens would benefit from stopping down one or two stops, but unless I see a difference I don't worry about it. Stopping down = slow shutter speed or higher ISO, either of which would probably offset the benefit gained by shooting at the optimum f stop. I do notice a loss of sharpness when stopping down to f16 or beyond, I assume due to diffraction. So, as a general rule of thumb I try to stick with f8 or at the most f11 . Makes for nicer backgrounds as well. For general shooting I find f5.6 to usually be fine for DOF. You really just got to try out your lenses and see what you experience. MCC -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
The optimum aperture does make a noticeable difference in sharpness with most good glass, but using it shouldn't overrule your DOF needs. With the K-5, you can set your program mode to choose the MTF aperture when you push the green button. On the new DA* zooms, it comes early -- f4 in many cases. It varies on individual lenses with focal length, and program mode recognizes that. In my experience the optimum ap on most older Pentax glass is more typically f8 or even f11. Counting on DOF to achieve sharpness is just wrongheaded in most cases. (Shooting from the hip at hyper focal distance would be an exception.). But by and large focus has to be accurate and DOF optimum for the job. Small aps, in the f16 and smaller range do cause loss of sharpness due to diffraction, but when you need a small ap for extreme DOF, you have to bite the bullet and go for it. Or shoot off a tripod with different focus points and composite the result. On Jun 4, 2012, at 6:22 PM, Larry Colen wrote: I was thinking about my quest for sharpness, and was considering trying to do some research into what the aperture sweet spot is for each lens, and was wondering if anyone had already made a chart of them. Then I wondered how much it really matters. I've heard a couple of stops down from wide open, anywhere between f/8 and f/16, and a couple other rules of thumb. I do know that on some lenses, particularly the FA50/1.4, that stopping it down a couple of stops from wide open, makes a huge difference. And I suspect that if you look on an MTF chart, you might be able to easily see the difference between f/4 and f/8, but is there a practical noticeable difference? There is also the question of sharpness at the critical focus distance, and overall sharpness. That a lens might be sharper at f/4 than f/16 at the focal distance, but with a lot more depth of field, more of the photo will be sharper at f/16, than at f/64. I'm primarily interested in answers based on personal, practical experience, rather than theory. My hunch is that as long as I'm not too close to wide open, or pushing diffraction limits, optimizing aperture for sharpness is not the most productive place to spend my time and energy. That I'm generally best optimizing the aperture for the picture, and not trying to optimize the aperture for MTF. -- Larry Colen l...@red4est.com sent from i4est -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
Don't forget that at about f8 diffraction effects will begin to rear it's ugly head. So if your maximum aperture is 4.0 diffraction will start to steal sharpness using that two stops down rule of thumb. It's worse the shorter the lens gets as the actual physical aperture is what controls diffraction, (and DOF as well). On 6/4/2012 6:22 PM, Larry Colen wrote: I was thinking about my quest for sharpness, and was considering trying to do some research into what the aperture sweet spot is for each lens, and was wondering if anyone had already made a chart of them. Then I wondered how much it really matters. I've heard a couple of stops down from wide open, anywhere between f/8 and f/16, and a couple other rules of thumb. I do know that on some lenses, particularly the FA50/1.4, that stopping it down a couple of stops from wide open, makes a huge difference. And I suspect that if you look on an MTF chart, you might be able to easily see the difference between f/4 and f/8, but is there a practical noticeable difference? There is also the question of sharpness at the critical focus distance, and overall sharpness. That a lens might be sharper at f/4 than f/16 at the focal distance, but with a lot more depth of field, more of the photo will be sharper at f/16, than at f/64. I'm primarily interested in answers based on personal, practical experience, rather than theory. My hunch is that as long as I'm not too close to wide open, or pushing diffraction limits, optimizing aperture for sharpness is not the most productive place to spend my time and energy. That I'm generally best optimizing the aperture for the picture, and not trying to optimize the aperture for MTF. -- Larry Colen l...@red4est.com sent from i4est -- Don't lose heart! They might want to cut it out, and they'll want to avoid a lengthily search. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
IMO in this kind of discussion it just might be useful to play the role of devil's advocate. Most of my shooting not for my own pleasure is for Galia's class. When it started I was obsessed with technical quality - sharpness, etc. As time goes by, I am starting to understand that slightly (notice, not badly, just slightly) soft or slightly blurred shot with interesting moment caught on camera is much more fun than sharp but uninteresting photograph. So, I don't dwell too much into optimizing everything - I just shoot trying to catch a moment. Wearing my regular hat, I should say that I'd line up with Bruce Walker - each specific lens has its own character. E.g. my FA 50/1.4 is probably sharper than average wide open because according to its previous owner it was a hard decision to sell it to me over DA* 55/1.4 and it is kind of known that DA* 55/1.4 is rather sharp wide open. Another example is A 50/1.2 which I shoot wide open a lot just for the heck of it. I've noticed (yet to figure out this in a way rigorous enough to spot it before the shot) that sometimes it produces surprisingly sharp results although mostly it glows ever so slightly. Other than that, all my prime lenses are sharp enough for me from f/2.8 and zoom lenses are sharp enough from f/3.5-f/4.0 which is indeed a stop or so from the wide open (except A 50/1.2 but I wouldn't shoot it just for sharpness anyway). On 6/5/2012 01:22, Larry Colen wrote: My hunch is that as long as I'm not too close to wide open, or pushing diffraction limits, optimizing aperture for sharpness is not the most productive place to spend my time and energy. That I'm generally best optimizing the aperture for the picture, and not trying to optimize the aperture for MTF. Well, yes. But given that you like bracketing, Larry, I suggest the following simple experiment. Set up a semi-serious shoot - I mean the one where you won't be shooting brick walls (I'd hate to suggest to shoot brick walls to anyone, especially for my friends) and configure your K-5 for 5 shots bracket. I reckon it should be possible to fix shutter speed and let the camera vary the aperture. I would even suggest to do it twice - off the tripod and hand-held. The studying of results may be worth your while. Boris -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: How much difference does optimizing the aperture make?
I personally know by memory for the prime lenses I used the most, and out of personal experimentation in real world shooting -just because I like to know- although P mode with MTF program will get you there easily. For the non-chip lenses I guess a couple of clicks from wide open. The ones for me that I found is worth knowing (partly because I used them often) are the 43/1.9 (some magic happens at f4 and 5.6), 31/1.8 (f5.6), 21/3.2 (f8) and 15/4 (f8 or f11). In some cases finding those sweet spots rekindled some lens love. And I also know that I get slightly sharper images with the 35/2 than the 31/1.8 @f2, that the DA40/2.8 is slightly sharper at 2.8 than the 43/1.9 at f2.8 and that the 50/1.4 gets ok at f2; for the rest I don't care that much/don't know/don't shoot with them that often Photozone.de has charts that I found pretty accurate for the lenses I have; and I used them just to answer questions like is the 16-45 better @ 16 than the 12-24 @ 16? without having to test myself (which I won't do anyway) On Mon, Jun 4, 2012 at 6:22 PM, Larry Colen l...@red4est.com wrote: I was thinking about my quest for sharpness, and was considering trying to do some research into what the aperture sweet spot is for each lens, and was wondering if anyone had already made a chart of them. Then I wondered how much it really matters. I've heard a couple of stops down from wide open, anywhere between f/8 and f/16, and a couple other rules of thumb. I do know that on some lenses, particularly the FA50/1.4, that stopping it down a couple of stops from wide open, makes a huge difference. And I suspect that if you look on an MTF chart, you might be able to easily see the difference between f/4 and f/8, but is there a practical noticeable difference? There is also the question of sharpness at the critical focus distance, and overall sharpness. That a lens might be sharper at f/4 than f/16 at the focal distance, but with a lot more depth of field, more of the photo will be sharper at f/16, than at f/64. I'm primarily interested in answers based on personal, practical experience, rather than theory. My hunch is that as long as I'm not too close to wide open, or pushing diffraction limits, optimizing aperture for sharpness is not the most productive place to spend my time and energy. That I'm generally best optimizing the aperture for the picture, and not trying to optimize the aperture for MTF. -- Larry Colen l...@red4est.com sent from i4est -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions. -- http://www.flickr.com/photos/ferand/ -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
