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12-16-2017, 07:17 AM - 1 Like   #106
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QuoteOriginally posted by Ian Stuart Forsyth Quote
seeing how you never answered my question here I feel this next question will fall also on deaf ears
If you can do everything in your head riddle me this at what f/stop do I need to have 6 feet to infinity and where do I place the hyper focal distance when using a 50mm lens
Using my DoF scale on my 50 I'd set the lens at ƒ16 and 15 feet. 2.8 doesn't give you any DoF at all hardly so I have no clue what you are talking about there.

And as I said, my output size is unknown when taking an image, every image I take could be blown up to 30x20 should I decide to sell it, and I shoot like every image will be that size. because I make more money that way.The whole concept of adjusting the required resolution to something less than the max because it will be smaller image, just doesn't appeal to me, at all. IN fact I avoid ƒ16, the loss in resolution is noticeable. I look for images that will be good at ƒ11 or less. 99% of my images ar shot from ƒ5.6 to ƒ11. IN most cases that's the sharpest part of the lens with the most DOF.

Without the DoF scale I Just set to ƒ8 or ƒ11 and focus 1/3 into the frame. I'd have to actually do an image to find out what my parameters are. But 50mm, ƒ16, 6 feet to infinity in focus, that I carry around in my head. That's kind of the magic internal reference point for many photographers. That being said at the same settings, a 35mm lens on APS-c would be a better bet.

If you always shoot for an image within the acceptable parameters for the lens. You always get an good image. It's only when you go outside the acceptable parameters of the lens any of this makes any sense.

If you use large pixel sensors, you want to shoot the lens at it's sharpest position, if you have smaller pixels you still want to shoot the lens at it's sharpest. Your diffraction limit for both APS_c and FF is between ƒ5.6 and ƒ8 on most lenses. I'm not seeing how you are improving on that knowledgeledge, unless you are trying to tell me to take images I would consider throw aways.

My theory has always been "walk around until you get the image you want, visually appealing, but within the parameters for excellent tech. as defined by the camera." Not take the first image you see and make it work.


Last edited by normhead; 12-16-2017 at 07:54 AM.
12-16-2017, 11:34 AM   #107
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QuoteOriginally posted by Ian Stuart Forsyth Quote
If you ever followed how Ansel managed his exposures, how he applied it to zones and to the DR of his selected film, I wouldn't doubt that he used a method where his own model of DOF was based solely on a resolution of the film he used.
Adams, the Group f/64, and large format photographers had and still have the added benefit of tilt, swings, shift, and rise/fall lens and film adjustments when it comes to dealing with their plane of focus (Sheimpflug Principle) and DOF.

Although defocusing can be achieved digitally, and there is the Rokinon Tilt-Shift 24mm f/3.5 ED AS UMC FF option for Pentax, wouldn't it be cool if the next model Pentax had a sensor that had the same movements as large format to better control DOF?
12-17-2017, 09:23 AM   #108
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Phew !...what a thread and then some🙃......by page four it felt like I'd accidentally delved into War and Peace...so hands up - although a total amateur I found it all a fascinating read and could feel the passion in many of the comments...in the same way that same passion has resulted in images that for me are wonderful to look at...in an early page @normhead suggested in a post that if someone did not have a working understanding of how hyperfocal distance works they should just 'fess up and ask for help...I can see advantages with apps and such but personally the idea of having stuff in my head rather than on my phone really appeals to me

@normhead - please could you point me to your preferred link so that I can read more on hyperfocal distance ?...and thanks for your input sir
12-17-2017, 11:08 AM - 1 Like   #109
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QuoteOriginally posted by Burnin' Coal Quote
Phew !...what a thread and then some��......by page four it felt like I'd accidentally delved into War and Peace...so hands up - although a total amateur I found it all a fascinating read and could feel the passion in many of the comments...in the same way that same passion has resulted in images that for me are wonderful to look at...in an early page @normhead suggested in a post that if someone did not have a working understanding of how hyperfocal distance works they should just 'fess up and ask for help...I can see advantages with apps and such but personally the idea of having stuff in my head rather than on my phone really appeals to me

@normhead - please could you point me to your preferred link so that I can read more on hyperfocal distance ?...and thanks for your input sir
I learned this stuff back in 67 during my year at Ryerson Politech using 8x10 and 4x5 tilt shift cameras. Concepts like the focal plane, DoF, etc. you get to be really aware of because you have control of it all. And the larger the format the more you have to be aware of hyperlocal focussing.

So that was at least 20 years before the internet. I honestly don't know of a good place to point you.

But the basic concept is pretty simple.

With an -stop of 1.4 your DoF is so thing, you can think of it as a huge sheet of cardboard in front of your camera, parallel to the sensor in a SLR type camera. As you stop down the focal plane expands to become a huge imaginary box, and everything inside the box is in focus, with more and more depth. With most hyperlocal landscape, you want to set the back of the box so infinity is in focus, and the box extends as far forward as possible towards the camera. But you don't want the box to be too big. Once you reach the diffraction limit of the lens, probably just after 5.6 (on APS_c or FF, on 8x10 film Ansel Adams was a member of the 64 club, the larger the format, the smaller aperture you can use before you hit the diffraction limit.)you start to lose resolution to diffraction. So for the sharpest image you really don't want to go more than 8, but 11 is usually pretty functional as well.

As you move the focus point back towards the minimum focusing distance the whole "in focus box" moves forward. So on macro you are going set the "box"

The key to hyperlocal for macro is to realize that your DoF is very narrow to start with, and that 1/3 of the DoF is infront of the focal point, and 2/3s is behind.

The concepts are pretty simple it's learning to implement it that takes time.

And looking at Ian's ice image above, that type of shot where you can tilt the "box" so it fits your scene better, it a piece of cake with a tilt shift camera. part of my objection. A DSLR is just not the right tool for the job in that type of image although with a tilt shift lens, you can do better. Not as good as you can do tilting both the lens and the sensor, but better than a fixed parallel to the film plane lens.

If you do find a good link let me know.


Last edited by normhead; 12-17-2017 at 11:39 AM.
12-17-2017, 11:25 AM - 3 Likes   #110
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QuoteOriginally posted by Burnin' Coal Quote
@normhead - please could you point me to your preferred link so that I can read more on hyperfocal distance ?...and thanks for your input sir
I know this link is polarizing to some members, but they have links to articles, FAQs, and apps that has helped many of my students:

Depth of Field Articles
12-17-2017, 11:41 AM   #111
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@normhead - years of experience is one thing...being able to condense that experience into a concise explanation that is comprehensible to one unschooled is no small thing...your words enable some key concepts to take root and that makes me happy at the start of my journey

@alex645 - that's what I was after as well

Thankyou both
12-17-2017, 11:43 AM   #112
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The simplest place to start is using the markings on your lens, a description can be found here: Using DOF Scales *. Be aware that this scale is calibrated according to the lens makers assumptions on the format you're using it on, as well as the final print size and viewing conditions. It's an easy place to start though, and you'll always have this reference attached to your lens.

A good reference on hyperfocal distance and a way to make custom charts: Understanding Your Camera’s Hyperfocal Distance

* edit- this particular bit (and more!) is also covered on the site Alex gave: http://www.dofmaster.com/hyperfocal.html

QuoteOriginally posted by normhead Quote
The key to hyperlocal for macro is to realize that your DoF is very narrow to start with, and that 1/3 of the DoF is infront of the focal point, and 2/3s is behind.
The "1/3 near 2/3 far" is accurate at 1/3 the hyperfocal distance, it approaches an even split as you head down to the macro world.
12-17-2017, 12:35 PM - 1 Like   #113
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QuoteOriginally posted by BrianR Quote


The "1/3 near 2/3 far" is accurate at 1/3 the hyperfocal distance, it approaches an even split as you head down to the macro world.
I always use AF so my focus is so imprecise it's all hit and miss down there for me. That's good stuff for manual focusers to know. Any serious macro user should definitely be using manual focus.

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