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04-12-2016, 05:10 PM   #31
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QuoteOriginally posted by osv Quote
of course you'll chimp it in the lcd afterwards anyway, which is really no different than focusing it with liveview in the first place.
QuoteOriginally posted by osv Quote
that's another easy manual focus situation, because you can pre-focus exactly where you want the sharpest part of the pic, just hit the shutter button when the train reaches the spot... train speed is irrelevant.

"right" is subjective... did you, for instance, point a laser measuring device at the object to measure the distance? and of course you've previously tested and confirmed that the markings on the lens barrel are accurate at their respective measured distances? doubtful, especially in the case of a zoom, or a lens that doesn't have any distance markings on the barrel to begin with.
I kind of question your experience with the older "obsolete" technology in this setting. The point is that I want the entire thing in focus - so I want assurance that both the end near me and the end away from me will be in focus. If I glance down at the lens and see that the the focus I have set "goes to infinity", then I have that assurance. The relevance of the speed is that "chimping" afterwards would be of zero use to me, because I don't have a second chance at taking the picture - I need to be sure before I press the shutter button that the f-stop I've chosen will give me sufficient DOF.

04-12-2016, 08:21 PM   #32
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QuoteOriginally posted by reh321 Quote
I kind of question your experience with the older "obsolete" technology in this setting. The point is that I want the entire thing in focus - so I want assurance that both the end near me and the end away from me will be in focus. If I glance down at the lens and see that the the focus I have set "goes to infinity", then I have that assurance.
you might have thought that you had assurance with low-rez film slop, but that's not what you are using today.

what are you going to do if your lens doesn't have markings on the barrel? you'll be lost some modern lenses don't even have infinity hard stops, what are you gonna do then?

QuoteOriginally posted by reh321 Quote
The relevance of the speed is that "chimping" afterwards would be of zero use to me, because I don't have a second chance at taking the picture - I need to be sure before I press the shutter button that the f-stop I've chosen will give me sufficient DOF.
speed of the train is not relevant to manually setting the focus point for this shot, ahead of time... i've taken over 10,000 fast action pics, i know all about only having one instant to get one shot, that's why i do it like i'm telling you as often as possible, with manual focus using magnified liveview; the only thing left to chance is hitting the shutter button at the right time.

i can understand not having enough experience to know how much dof you'll get with a lens, but with liveview magnification you can zoom in ahead of time and see what's in focus in the area where you'll be setting focus... you can see the dof, change it if you want, and set perfect focus as well.
04-12-2016, 08:32 PM   #33
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QuoteOriginally posted by osv Quote
you might have thought that you had assurance with low-rez film slop, but that's not what you are using today.
You are on a roll recently

I too question your experience, particularly in regard to evaluating DOF using a magnified view. It does not work on a view camera ground glass or on my K-3 live view at 100 and it does not work on your Sony either. Magnification defeats DOF...at least it does for most people's perception. In addition, the DOF scales on the lens barrel are based on calculations that assume infinite media resolution. "Film slop" resolution is not a consideration. I would have thought that you knew that.


Steve

(...had to grin...prefocus is the best option when shooting action with the A7R...tragically slow AF...)

Last edited by stevebrot; 04-12-2016 at 08:37 PM.
04-12-2016, 08:59 PM   #34
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QuoteOriginally posted by stevebrot Quote
You are on a roll recently
i'm not the only one

QuoteOriginally posted by stevebrot Quote
I too question your experience, particularly in regard to evaluating DOF using a magnified view. It does not work on a view camera ground glass
is this the part where you start an argument that ovf is live view? lol

QuoteOriginally posted by stevebrot Quote
it does not work on your Sony either. Magnification defeats DOF...at least it does for most people's perception.
you've clearly never tried it... the reason it works is because magnification is not relevant to focus; if part of the shot is soft because of dof, that's not going to change just because you are zoomed into it.

think about it... when you are viewing a pic in photoshop, and part of it is out of focus, does the soft part suddenly get sharp when you zoom in to 100%?

you people can't see the forest for the trees... all you have to do here is use magnification to see what part of the pic is oof, and evaluate how much it's oof, because that's the part that's past the dof limit.

QuoteOriginally posted by stevebrot Quote
In addition, the DOF scales on the lens barrel are based on calculations that assume infinite media resolution. "Film slop" resolution is not a consideration. I would have thought that you knew that.
film slop means that you can't tell whether the dof limits are sharp or not.. that should be pretty obvious, even to a film guy

---------- Post added 04-12-16 at 09:07 PM ----------

QuoteOriginally posted by stevebrot Quote
(...had to grin...prefocus is the best option when shooting action with the A7R...tragically slow AF...)
i wouldn't be too sure about that... the pdaf in my laea4, for example, makes a7r af plenty fast



04-12-2016, 09:36 PM   #35
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QuoteOriginally posted by osv Quote
you might have thought that you had assurance with low-rez film slop, but that's not what you are using today.
what are you going to do if your lens doesn't have markings on the barrel? you'll be lost some modern lenses don't even have infinity hard stops, what are you gonna do then?
I make the best of the situation. My point was that the "obsolete" method is actually better than the supposedly modern methods. The fact that modern manufacturers don't do something is not proof of anything other than the fact that they don't do it anymore.

QuoteOriginally posted by osv Quote
speed of the train is not relevant to manually setting the focus point for this shot, ahead of time... i've taken over 10,000 fast action pics, i know all about only having one instant to get one shot, that's why i do it like i'm telling you as often as possible, with manual focus using magnified liveview; the only thing left to chance is hitting the shutter button at the right time.
Please go back and read my original comment for content. I mentioned speed because of your specific comment about "chimping", which is something you do after you take the picture; my comment was that the "obsolete" markings give me the information before I take the picture; the relevance of speed is that no human being can "chimp". find a problem, and re-take the picture when the object is moving {and I don't find taking a picture without an actual object to be nearly as useful as having the "obsolete" markings}.

QuoteOriginally posted by osv Quote
i can understand not having enough experience to know how much dof you'll get with a lens, but with liveview magnification you can zoom in ahead of time and see what's in focus in the area where you'll be setting focus... you can see the dof, change it if you want, and set perfect focus as well.
I've been doing this for fifty years. I have plenty of experience. {and if experience were that helpful, you wouldn't be "chimping" on your 10,000th+1 picture} Typically I'm at places where tripods are not allowed, or at best awkward, so there is no way to do liveview in a stable manner. Hold the camera in "zombie" position and use live-view if that works for you; it does not work for me. You may continue commenting if you wish, but we've been past all these stations several times already, so I'm off to something interesting.
04-12-2016, 10:25 PM   #36
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QuoteOriginally posted by osv Quote
is this the part where you start an argument that ovf is live view? lol
No this is the part where I remind you that the image on the ground glass is natively 100% and that adding a magnifier, while helpful for assessing fine focus at various sections of the frame, gives no indication of DOF on any part of the frame. The ground glass is simply the closest the one can get to viewing the image as it exists as light, not as an interpretation of light...the difference between reality and a virtual construct. Can it be used to evaluate DOF? No...the surface is too granular. Large format photographers evaluate fine focus and effectiveness of Scheimpflug with a magnifier on the ground glass and use DOF tables/calculators to estimate that aspect.

Reading your comments, there is a consistent lack of understanding of gear and technique outside your choices and a tendency to chide and demean other users on this site whose practice involves tools different from your kit. Did it occur to you that many of us chose our current kit over what you use and did so from an informed perspective. For example, I evaluated the A7 and A7R before I purchased my K-3. My rational? Despite the high build quality, broad compatibility with adapted lenses, and excellent sensor, I found the EVF unsuitable, the AF slow, the shutter unreasonably loud, and the available lens choices in Sony E mount at that time embarrassingly slim. Are the A7 cameras great tools? Absolutely! Are they an obvious best choice? No, though for many they work quite well. I am in frequent conversation with several A7-series users who do very, very good work and most also use other systems including film cameras. If I see a good one used, I may yet add an A7 to my kit, but not as the solution to all things photographic.

Now perhaps I and the other users on this site with whom you spar lack experience. I have only been pushing the shutter button for close to 50 years and digital for the last 15. My perspective from that time span is that 95% of what matters for digital photography is also common to film and the remaining 5% is analogous. The laws of physics apply across the board as do the principles of optical design and visual perception.


Steve

Last edited by stevebrot; 04-12-2016 at 10:33 PM.
04-12-2016, 10:33 PM   #37
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QuoteOriginally posted by reh321 Quote
I make the best of the situation. My point was that the "obsolete" method is actually better than the supposedly modern methods.
i'm saying that it's sloppy; you guess at the distance, you guess at the accuracy of the barrel markings, etc.

QuoteOriginally posted by reh321 Quote
Please go back and read my original comment for content. I mentioned speed because of your specific comment about "chimping", which is something you do after you take the picture; my comment was that the "obsolete" markings give me the information before I take the picture;
no, when i repeatedly state magnification with liveview, it clearly means before the picture is taken.

QuoteOriginally posted by reh321 Quote
the relevance of speed is that no human being can "chimp". find a problem, and re-take the picture
see above.

QuoteOriginally posted by reh321 Quote
I've been doing this for fifty years. I have plenty of experience.
you sure don't have any experience doing it the way that i outlined... yes, liveview in the lcd sucks, that's why i went mirrorless, i can do it with the evf, but the principles are the same.

---------- Post added 04-12-16 at 11:20 PM ----------

QuoteOriginally posted by stevebrot Quote
No this is the part where I remind you that the image on the ground glass is natively 100%
seriously? i thought that you were joking about an ovf being described as liveview.

of course it's not the same as liveview in the lcd, i never claimed that it was, i don't see the relevance to the focus techniques that i've outlined, and i don't see how this is sony vs. the world either, since magnification can be done with just about any modern camera that has an lcd.

people, there is no need to get all butt-hurt here if you don't want to learn how to improve your camera technique, well, just don't... go ahead and keep using the same sloppy hyperfocal focusing that you were using fifty years ago... of course it's not going to matter on a modern 36mp camera, not at all
04-13-2016, 05:56 AM   #38
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Can latest EVFs display stop down DOF?

I have the Olympus VF-3 here for M43.
I just tried it at 42mm ranging between f/5.6 ~/22
It has live view boost on/off -off where the brightness has to be corrected by adjusting shutter as the f/ changes.

But I think it is a fudge - the aperture does not actually stop down does it?

I did a close focus over range f/5.6 ~ 22 and the oof on a distant tree did not change.
I can't find any mention of DOF in the Oly manual.

The Pentax K-01 has ability to assign one of the 2 top buttons for DOF preview,
but not available in my case because I need to assign other functions to use the -M lenses

04-13-2016, 06:00 AM   #39
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QuoteOriginally posted by stevebrot Quote
I use an Android app simply called "DoF Calc" that provides near/far focus limit as well as the hyperfocal distance, all at a glance. My only complaint is that the distance units are a little course.


Steve
Hyper Focal is also an Android app and takes the measurement to the 3rd decimal point, you may want to give it a shot.
04-13-2016, 08:12 AM   #40
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QuoteOriginally posted by wombat2go Quote
Can latest EVFs display stop down DOF?
oly cameras keep the aperture open all the time, they do not have true wysiwyg capability... you can usually push a button for dof preview, but it still doesn't show you what the exposure of the shot will look like.

live boost and such is the oly way of turning up gain in the evf.

people who own oly cameras are in denial about it but you saw the issue right away.

Olympus OM-D EM 5 Mark II - Under exposed images: Micro Four Thirds Talk Forum: Digital Photography Review
04-13-2016, 08:22 AM   #41
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QuoteOriginally posted by osv Quote
people, there is no need to get all butt-hurt here if you don't want to learn how to improve your camera technique, well, just don't... go ahead and keep using the same sloppy hyperfocal focusing that you were using fifty years ago... of course it's not going to matter on a modern 36mp camera, not at all
...and you can continue to use the same "sloppy camera technique" you used for the photo you shared above. I have no idea what you did, but you missed focus by several feet, unless you intended it to be the leading edge of the rear fender. That being said, the image works and unless all 36 Mpx were printed to 16x20 and hung in a narrow hallway (short viewing distance), it is unlikely that any viewer would complain...unless, of course, it were submitted for gallery competition. The soft and blurred areas of the frame emphasis the dynamic of speed. (Let me guess...f/11 @ 1/1000s?) Good work.

That brings us back to hyperfocal technique and other things related to DOF. After all, your above photo uses available DOF and appropriate shutter speed to make the image possible. Leveraging the hyperfocal is just another tool in the bag of tricks and works very well for many types of photography. Yes, it is sloppy, but so is using AF at 4 fps at 50 yards at f/11 (spray 'n pray).
It is all part of the art of intelligent estimation.
Strangely, that art works equally well with obsolete tech as with the latest and greatest (Sony A7R vs. A7Rii, for example ) It is amazing what can be done in good light using a primitive tool such as a K10D (see HERE).

To bring things back on topic...How is DOF (and hyperfocal, by extension) properly leveraged? In my practice and IMHO, it is simple:
  • DOF is a fact of photographic life. It is always there and something to be considered for every shot.
  • Remember that calculated DOF for the final viewed image is always an estimate with many assumptions*
  • If focus counts, be careful with where you place it. There is always only one plane of focus. The viewer's "eye" will forgive a lot, but if the leading edges of the intended subject are not sharp, the eye tends to complain.
  • There is more to subject isolation than shallow DOF
  • There are limits to deep DOF and they come up fast
  • Magnification defeats DOF. Stand close or magnify the view and DOF evaporates.
  • What you see in even the best optical or electronic viewfinder probably shows exaggerated DOF unless magnified and then all bets are off. DOF preview is nice, but not definitive. Ditto for chimping.
  • Hyperfocal works, though not for all subjects and not when viewed with a critical eye
Is using the hyperfocal sloppy or unprofessional or obsolete? If he were not dead, I would ask Henri Cartier-Bresson. He is still known (sort of a legend actually) for his ability to catch that thin sliver in time that defines emotional impact...In his words, "the decisive moment". Was he sloppy or unprofessional? Given the gear he used and the photos that resulted, it is almost a given that he leveraged the hyperfocal in some form. It is also likely that he estimated exposure. What is known is that he was notoriously sloppy about technique and very demanding of his assistants who actually processed his film and made the prints. Ironically, his preferred tool, so-called Barnack body Leica 35mm rangefinder cameras, feature a very accurate rangefinder focus system that would have allowed him to consistently "nail" focus every time should he have used it. Leica uses a similar system today and in practice, it is very fast.

Does anyone view Cartier-Bresson "large and up close" and gaze in awe at the technical brilliance? Ummmm...no...You don't have to view large to appreciate his work. I am not Cartier-Bresson, but I used hyperfocal for this shot along with rather rude Ferrania Solaris film and obsolete meterless Canon P camera and cheap (not crappy) former Soviet lens.



Sucks in all regards, technically, but I like it and it does what I intended when I pressed the shutter release.


Steve

* Despite rumors to the contrary, resolution of the capture medium does not figure into the calculation...go figure

Last edited by stevebrot; 04-13-2016 at 08:43 AM.
04-13-2016, 11:18 AM   #42
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QuoteOriginally posted by stevebrot Quote
...and you can continue to use the same "sloppy camera technique" you used for the photo you shared above. I have no idea what you did, but you missed focus by several feet, unless you intended it to be the leading edge of the rear fender.
focus is on the middle of the car, right about where i wanted it, anytime that you can focus on a face in an action photo it's a win f/7.1, 1/1250th, 420mm, not enough dof to cover the length of the car, f/7.1 on ff isn't enough dof even with a 28mm prime, but i actually prefer that look in this telephoto context, it works because it puts emphasis on the driver.

i think that we can agree that hyperfocal techniques would have completely failed there.

QuoteOriginally posted by stevebrot Quote
[*]Magnification defeats DOF. Stand close or magnify the view and DOF evaporates.
no, it doesn't change the dof that the photo was taken at, and it doesn't change where the photo is blurry from being outside of the range of dof... liveview works the same way.

all you have to do is to zoom in and see where the softness in the shot really is at, and you'll know the true limits of the dof.

going off on a tangent here... changing distance confuses background blur with the actual dof, but it doesn't necessarily have to alter the true dof: "Figure 3. A: Gromit photographed with a 100-mm lens at f/4. B: Gromit photographed with a 28-mm lens at f/4. DOF is the same."
Depth of field

QuoteOriginally posted by stevebrot Quote
Is using the hyperfocal sloppy or unprofessional or obsolete? If he were not dead, I would ask Henri Cartier-Bresson.
show me any henri cartier-bresson photo that's sharp... if you really think that mushy look is da bomb, why do you own a k-3? you are contradicting yourself... you could throw away your 35mm film bodies, smear vasoline all over your lenses, and wala, you've got film slop like bresson had

i like that shot, btw!

Last edited by osv; 04-13-2016 at 11:27 AM.
04-13-2016, 12:03 PM   #43
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here is a 100% ooc crop of that shot, i wasn't really zoomed in enough, it's a weak example but you'll get the idea... i lifted the shadows, but didn't sharpen any more than what the jpeg processing did.

the front shock area is more blurry than the logo, and the racing strip going up to the top of the pic loses sharpness towards the end; the engine cage bar behind the rear shock area is starting to blur... that's how you zoom in with liveview and determine what the actual dof is, it's far more accurate than any hyperfocal guessing.

the dof calculator says that i've got 85 feet of dof, lol
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Last edited by osv; 04-13-2016 at 12:09 PM.
04-13-2016, 12:27 PM   #44
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QuoteOriginally posted by osv Quote
going off on a tangent here... changing distance confuses background blur with the actual dof...
Dang...you simply don't get it do you? I guess you can't be blamed for that. No sense continuing this exchange.


Steve

Last edited by stevebrot; 04-13-2016 at 12:42 PM.
04-13-2016, 02:22 PM   #45
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QuoteOriginally posted by stevebrot Quote
Dang...you simply don't get it do you? I guess you can't be blamed for that. No sense continuing this exchange
no, i totally get it, you are the one who can't understand, even after i posted a pic that shows the exact dof, using magnification, which proves how that magnification in liveview can be used to set exact focus right where you want it.

yes, you go right on ahead and keep thinking that there is ~85' of dof in that shot no hard feelings, this is nothing personal.
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