Losing bokeh or quality when raising or lowering the aperture on P4P?
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Meta4
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The P4 pro lens works exactly like a similar lens would on an SLR and exhibits good image quality at all settings.
There are two reasons why you won't see much change in bokeh with changes in aperture.
It's a very wideangle lens (84°FOV), equivalent to a 24 mm lens on a 35 mm fill frame sensor camera.
It has a lot of depth of field at any aperture and as an aerial camera, it's not used for close focus.
???
Given it is a wide angle lens and often focus is often at infinity, bokeh isn't seen for the most part.
Even wide-open at f/2.8 at 50 feet distance shows 23' to Infinity for depth of focus on my DOF calculator. Small sensors are tough to get decent bokeh out of, imho, and include your cell phone camera for being tough also for bokeh unless a foot away.
Even wide-open at f/2.8 at 50 feet distance shows 23' to Infinity for depth of focus on my DOF calculator. Small sensors are tough to get decent bokeh out of, imho, and include your cell phone camera for being tough also for bokeh unless a foot away.
You may want to rethink your terminology here, perhaps concentrate more on the depth of focus rather than Bokeh. Bokeh of course provides for a subjective assessment of the appearance of out of focus areas, especially how bright point sources are rendered being smooth, creamy etc. The depth of focus, or probably better put, range of acceptable sharpness will be the same for any particular focal length and aperture Illuminating a given sensor/film frame. A discussion around Bokeh. We know Bokeh is a very important consideration for Macro and short telephoto and higher magnification lenses on 35mm DSLR cameras. We also know it has little relavence to wide angle lenses where the inherent depth of focus is, as mentioned by others, very deep. The lens in the phantom 4 pro has an actual focal length of about 8mm. Arguably an 8mm lens on a 35mm DSLR would not even require a focus ring so the Bokeh consideration would be irrelevent.
Yeah, bokeh really only applies at shallow DOF and that usually requires a combination of close distance and low f/# when using a wide angle lens like we have on the P4P. So, unless you are real close and use a very low f/# bokeh doesn't figure into it.
As far as ND filters are concerned there is some disagreement as to whether or not you need them -- I have one but never use it and haven't found a need for it. I generally shoot at 4K30, D-Cinelike, f/5.6, ISO100, -1/0/-1 custom setting, H.265, MP4, WB=5600-6000, and with those settings and no ND filter my shutter speed, controlled manually, ranges between 1/320 and 1/2500 with an average of about 1/1000. I do no notice objectionable artifacts of the higher shutter speed and actually it tends to result in sharper video -- perhaps some prefer softer video. Check out this video I shot with the above settings and tell me if you think a ND filter is needed.
Brian
As far as ND filters are concerned there is some disagreement as to whether or not you need them -- I have one but never use it and haven't found a need for it. I generally shoot at 4K30, D-Cinelike, f/5.6, ISO100, -1/0/-1 custom setting, H.265, MP4, WB=5600-6000, and with those settings and no ND filter my shutter speed, controlled manually, ranges between 1/320 and 1/2500 with an average of about 1/1000. I do no notice objectionable artifacts of the higher shutter speed and actually it tends to result in sharper video -- perhaps some prefer softer video. Check out this video I shot with the above settings and tell me if you think a ND filter is needed.
Brian
Forget about bokeh with these sensor/lens combo's for the most part as its very limited for aerial shots (there is 'some' minor background blur at f2.8 for subjects 5m-25m perhaps but its not worth thinking about or trying for). As for quality (sharpness) yes it will drop off rapidly at higher apertures. I tested all f stops for quality and sharpness - finding on mine f2.8-f4.0 were very similar with f3.2 the sharpest. It quickly deteriorated at f5.6 and above (enough that I have ruled out using f5.6 or above for photos. For video I might use f5.6 or a step more if I 'have' to as softer video is not an issue compared to photos (but still... my goto setting is f3.2 for both stills and video - if needed f2.8 or f4.0 - if desperate f5.6 or beyond).
As for ND filters I think they are a bit overrated or misunderstood in various aerial video. People just seem to want to sprout the old double the shutter rule without properly understanding or explaining when to and when not to use it. Like in your footage being high/far enough from the ground or close objects and moving nice and slow with the camera it is not really needed and will be sharper without it (that said if one was used it would not look bad either and some prefer the very slight blur at this distance/speed still even though one would be hard pressed to tell the difference anyway). For faster moving items closer to camera it is more useful and 'sometimes necessary' for creating motion blur that looks natural or better with blur (more blur or double the shutter rate amount of blur is not always the best look - for example total loss of all detail can occur making it look more like a timewarp effect - up close and fast over grass for example when aimed down at the grass only). This video gives a good example (the person waving their arms) of when a ND filter really should be used (but generally people also need to understand when it does not 'need' to be used and that a strict double the shutter rule actually can look worse too in certain scenes where perhaps a 4x shutter or more works better).
A guide to follow is: If there is a person or animal or object (car for example) close to camera and moving around getting the shutter speed down (with help of an ND if necessary) will create more natural motion... On the other hand, flying over or filming static subjects such as the ground it is less important and more creative depending on the look you are after. If 'IT' is moving lower the shutter but if the 'camera' is moving consider all options (speed and distance to static subject) - and yes they are more or less the same (one or the other is moving) but not exactly the same
just to be confusing.
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Meta4
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I wonder if it's your lens or your testing?
There have been quite a few tests showing a much bigger range than that producing good quality.
I do most shooting at f5.6 and think it's superb.
For stills you might want to stay below f/5 but for video f/5.6 is my standard aperture setting. Also, there's a trade off between the best setting to minimize diffraction blurring, typically a low f/#, and achieving a large DOF, typically a higher f/# so splitting the difference will put you somewhere between the two. If the FOV is pretty much at a single distance using a lower f/# will get the greatest detail, but if you have near and far items in you FOV and you wish they both be in reasonable focus then you need to use a higher f/# to get the maximum detail. And, as with your experience f/5.6 seems to work really well for me and my videos. The Paria video I posted in post #5 of this thread was shot using f/5.6 and I'd challenge anyone to point out loss of detail due to diffraction.
Dingoz suggestion that f/3.2 is the hot setup is counter to my experience and I wonder how he quantifies that reasoning. If I take picture or video of a test chart, for example, the distance is pretty near the same for everything and that would certainly favor a lower f/#, but in more real world cases you need more DOF than that.
I also have some high end DSLR's such as the Nikon D800E and I have found that when shooting landscapes the maximum detail is generally around f/7.1. Of course, the sensor in the D800E is much larger, but it's also 36MP so the pixel pitch is not much larger than the sensor in the P4P. Given that the pixel pitch in the P4P is a bit less the f/# were max detail is achieved will be less than the f/7.1 with the D800E. I should explain that my testing of the D800E that revealed f/7.1 being about the sweet spot involved shooting the same scene with the same lens and varying the aperture and then reviewing to see which image produces the largest file size which indicates recorded detail and in my experience that's right at f/6.3-f/7.1 Again, if the FOV is all pretty much the same distance then a lower f/#, say f/4, might makes sense but if you have objects very near and far and you want them all to be in reasonable focus then a higher f/#, even f/11 might be preferred.
The P4P cameras sensor is much smaller with a tighter pixel pitch so the aperture settings would need to be less than the D800E. So, while I tend to shoot my D800E at f/6.3-f/8 most of the time with the P4P, shooting video, I tend to stay in the f/5-f/5.6 range most of the time.
Brian
I would be interested to see any other tests... remember any links? Lens quality control variations would not surprise me.
Note in my testing this was for an object at 10m to infinity (keeping the object at 10m in sharp focus along with everything else to infinity).
Your post seemed to be more concerned with still imaging than video. Landscape work with the Nikon focus stacking will get you the sharpest print files, no question (assuming your glass is onto the task).
I find that f/7.1 provides enough DOF for 90% of my landscape work and there are other ways to skin a cat. You can, for example, use a longer tele lens and take multiple shots focused as needed then create a panorama. This way you can get still larger files and you can do some tweaking of focus for the individual shots. Interestingly, the new Nikon D850, and boy would I love to have one, can do in-camera focus stacking though external tools are probably still preferred. The automated way it takes the shots look to be the real winner.
Brian
Without having other tests to compare to it could be my copy of the lens but... for my real world test scene closest object was at 10m and furthest as 100m.
I first tested the manual focus dial at every step and found a very quick roll off. Basically the last 3 notches at the infinity end had everything in good focus from 10m to 100m (or infinity we could say). 1 notch off infinity was the hot spot for this range 10m to 100m all in focus. If 100m was the closest object then max infinity might be a fraction better. If 10m-50m was the scene then 2 notches off infinity might be better. That said it was splitting hairs as the last 3 notches had similar acceptable in focus throughout the 10m-100m range. All the other notches/markers beyond that towards close up/macro end of the manual focus slider rolled off 'very' quickly and all being worse and out of focus across the 10m-100m range in comparison (so the rest of the notches proved only suitable for objects from 1m-10m. This test was done at f2.8 and not in flight so stable as possible (have pics of this still).
I then tested every f stop using the same scene at the best in focus / sharpest setting from first test (1 notch off infinity for the 10m-100m range). f2.8-f4.0 were splitting hairs. f5.6 saw a loss of detail and sharpness but not too bad (but still worse than f3.2). beyond f5.6 it rolled off very quickly again with major loss of detail / sharpness. The loss of course due to diffraction. This was all with no perceivable gain in depth of focus or detail across the 100m range. I deleted this set of pics but will be re-testing for my own curiosity again.
Here is the focus test... car number plate at 10m... chair at about 35m... tree/bank on other side of water at 85m... top of tree line at 100m... a little bit of wind in the trees at play. Image at 100% size just cropped some of the top sky off.
Left side are close up/macro end of manual focus range and right side are infinity end of scale. Tested steps where 1 marker line was just visible above and below the slider position.
Left side are close up/macro end of manual focus range and right side are infinity end of scale. Tested steps where 1 marker line was just visible above and below the slider position.
Pixel peeping is frequently of little relavence, that is it probably rates with lowest significance in the mind of someone viewing the print. I suspect nobody ever won an award with a shot of a test chart. For what it’s worth there are technical aspects in the crops you have posted that suggest bigger issues than outright resolution. What is the blue in the water?
I do not understand your post at all...
Who is pixel peeping for a start... this test was solely done for myself to work out the manual focus settings for the sharpest results within the distance range. If I was viewing a print taken at the close up out of focus end of the scale (which is about 80% or more of the focus range) you would have to have very poor eyesight not to see that compared to an in focus image... particularly if a large wall print. Oh wait, I was pixel peeping to find out the sharpest setting to use so I suppose you are right... what a waste of time to figure this out once with a new camera... i should have just trusted the small screen image instead and the obscure focus peaking feature.
BTW the images are raw without any processing (no noise reduction or lens corrections or anything). The blue in the water looks like reflections... the colour noise in the water is how it is off this sensor untouched at ISO 100. I do not understand how resolution came into the topic nor these other sensor image quality aspects... I thought we were talking about aperture mainly and added a the focus test I previously did as a prelude to dof and f stop test.
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Meta4
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Thanks for that! I did see this one before too. So his finding was "I can't see real difference in sharpness from f2.8 up till f6.3" and later recommends f2.8-f5.6 as sweet spot.
My findings are not too much different at least. f2.8-f4.0 = f3.2 sweet spot middle vs f2.8-f5.6/f6.3 = f4.0/f4.5 sweet spot middle. So while variations are expected with this lens I do not think mine is way off his.
My test though was a bit different or at least showed more as I tested both the foreground object at 10m through to distant object at 100m for 'all' being in focus. It would be nice to see his foreground in all those shots too. I am curious to test this again so will look out for comparing only the 100m object across the aperture series vs the whole range of 10m-100m.
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I wasn’t having a shot at you specifically, I was sharing my general observation. I have performed similar tests to what you have done here with many lenses and for a time fell into the trap of letting the technical considerations take priority. Now- if I want to shoot at f1.2 for extremely shallow focus I will, even though I know a couple of stops closed down on the aperture will give a significantly sharper image viewed at 100%, I will also stop down to where I know I will see the effects of diffraction on a 100% view, the reality is there is two stops or greater latitude to where this will be perceptible to most people in a print viewed at a reasonable distance. It would be interesting to see how your test shots compare when all viewed full screen uncropped.I do not understand your post at all...
Who is pixel peeping for a start... this test was solely done for myself to work out the manual focus settings for the sharpest results within the distance range. If I was viewing a print taken at the close up out of focus end of the scale (which is about 80% or more of the focus range) you would have to have very poor eyesight not to see that compared to an in focus image... particularly if a large wall print. Oh wait, I was pixel peeping to find out the sharpest setting to use so I suppose you are right... what a waste of time to figure this out once with a new camera... i should have just trusted the small screen image instead and the obscure focus peaking feature which shows red up front and then also far in the distance many times.
BTW the images are are raw without any processing (no noise reduction or lens corrections or anything). The blue in the water looks like reflections... the colour noise in the water is how it is off this sensor untouched at ISO 100. I do not understand how resolution came into the topic nor these other sensor image quality aspects... I thought we were talking about aperture mainly and added a the focus test I previously did as a prelude to dof and f stop test.
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