Hello everbody,
i tried my look with some sparklers. Tested from 1,500 fps up to 25,00 fps.
I get the feeling, that I can't focus it any better but it still looks out of focus some times
video available in around 2 hours... i have to go to sleep now an let youtube do it's thing
https://youtu.be/E4sjlqmX4F8
PS: I finally get to test the DAIN program at one of my popcorn clips from my last video.
For only one clip that lastet about 20 seconds my computer took around 3 hours to create a 4 times slower video. ... But the result was stunningly good!!!
But for my kind of video hobby youtube thing, this tooks way too long. But maybe for single clips I can use it. But not for the whole video.
Well, that lens seems to not be the sharpest thing ever (just judging from all the Purple and Green Fringes there), but i think the biggest problem here is also depth of field, the Plane of focus, which is actually REALLY sharp is very shallow for Closeups like this. Filming Highspeed video in combination with the Closeup then also means, you propably cant just close the Lens down as much as you might want, to get an bright enough image. Since the Single Sparks fly all over the place, they are rarely actually in focus even if the Sparkler Stick itself is as sharp as you can get it. Also (i attached a croped Part of an image i took a while ago at an wedding), those Sparks never really look that sharp anyways, unless you have pretty high resolution. As you can see in my image, the Lines of the Sparks flying are always pretty wide and will look out of focus most of the time anyways, then the point where it "sparkles" is just a ton of fine lines and sometimes those also again break up into smaller bits. In those locations where they "sparkle" is a lot going on, which is propably too much detail to propperly capture on 720p resolution, unless you manage to get an even Closer Closeup of just one of the Sparks itself in focus. To sum up what i am trying to say, while it looks unsharp, if you look at single frames of the Video, it is propably as sharp as it will get with that lens at that resolution, you can sometimes see some 1px Wide lines, which are just as much in focus as they could.
That's strange, the focus plane should be deep enough. Because most of the time I filmed with f/10 or even higher ... even up to around f/20ish . The focus plane should be okay. At the time I was focusing, it looked sharp to me, but the end result was not that sharp at all. Maybe the upscaling did break it.
Maybe, even at a higher f-stop the focus plane of my lens is too shallow... for the next video I'll try my other lenses.
https://en.wikipedia.org/wiki/Diffraction-limited_system Well, if you stop down too far, you sure gain depth of field, but there Still might be diffraction which will make the Sharpness decrease again after a certain point. Depends heavily on the lens, but usually for smaller sensors like in the 1.4; f/11 and smaller can allready start to show sharpness limitations from Diffraction. If its a lens which is not specially designed for Closeups and /or Small apertures, it might show sooner on other lenses later, but just stopping a lens down all the Way doesnt mean its on its "sharpest" setting. Did this test with many of my lenses, shot an image at every apperture setting i could, and compared Sharpness between them, (its been a while since i did that), but most where sharpest at somewhere between f/2.8 to f/8. If you want to know for sure, might do a test on the lens you are using, to find out the "sharpest" setting of the apperture (in german its called "Förderliche Blende", couldnt find anything about it on Wiki or a propper translation, but i would go with "ideal Apperture"), found an Article about that in german, with some images kinda showing whats going on (had way more sharpness loss on very small Apperture settings in some of my own tests on my lenses, but i guess that is, because i tested mine on an really small sensor and those tests are propably FullFrame Or APS-C Sensor size, where the Effect isnt that extremely visible, unless you stop down really far, like f/64 or more, but it also depens a lot on the lenses itself, as i said.).