A99 Movie settings in "P" mode

[can_alpha]

This is my first post in this forum. Brief introduction here... basically, I'm a proud new owner of an A99. It's early days, but generally I am extremely happy with my purchase. It was the ideal choice for my needs.

Just to get right down to the point of my post. It could very well be me, but Sony has appeared to forgotten the 180 degree shutter rule in the "P" setting, whilst in movie mode. It's fairly common knowledge that the best "cinematic look" is achieved when shutter speed is set to approx twice that of the frame rate, ie. @ 60fps shutter should be set where ever possible to 1/120 (or 1/125). I also have an RX100, that tries its very best to stick to that very rule in "P" mode, it has (by default) the shutter speed set to 1/125. The RX100 sets the correct exposure by first automatically adjusting the Aperture (if you have a pre-assigned ISO setting) and only after the minimum (or maximum) aperture has been reached, the camera will then adjust the shutter speed accordingly in order to maintain the correct exposure.

Now, back to the A99....Ordinarily, I would select manual focus in order to access, the full manual mode, whereby one can then proceed to set, shutter, speed, ISO and Aperture, as one pleases. However, in certain "RUN & GUN" situations, where there's really no time to manually set everything up. I wanted to take advantage of the new features, like the follow focus (which is only available in "P" mode). Before I have a rant about sony, perhaps I am missing something. I know there are lots of highly knowledgeable people on this forum, so I would greatly appreciate some help and guidance, should I be missing something in the menu settings.

Hopefully I've made my concerns clear, and look forward to some responses!

Thanks in advance!

[pakodominguez]

I would love to read more abut his rule (t's fairly common knowledge that the best "cinematic look" is achieved when shutter speed is set to approx twice that of the frame rate,) can you please provide more information or links about it?
Thanks!
Pako

[David Kilpatrick]

I'm not sure this is a very well-defined rule. Until recently there was no such thing as 50 of 60fps standard film or video, everything was in the range between 16fps (very early movies) and 30fps (US standard domestic TV video) with nearly all professional movies other than IMAX and special high speed work done at 24fps.

Only one movie system - the rotating mirror or prism shutter synchronised with the movement of film a in Hulcher high speed cameras - ever allowed the shutter speed to be close to the frame rate. All other systems required the film to stop physically, be exposed, and move. For a 24fps movie the dwell and move times rarely allowed any shutter speed longer than 1/40th, and movie makers generally have felt that 1/50th to 1/60th give a natural look. This happens because when a subject moves fast, these speeds tend to blur the moving detail rather than freeze it, and this prevents the appearance of jerky sharp detail when projected.

Ideally the A99 should emulate this, but because of the way digital video works, it is almost able to give a 1/60th shutter at 60fps (which no standard cine camera could do). There's no great harm in this, but 1/120th would be better, as at 60fps we can put up with sharper moving detail and don't need each frame to have an element of movement blur. What is not needed is 1/500th or 1/2000th.

The AF of the A99, like the NEX models, requires f/3.5 for optimum on-sensor PDAF as well as effective contrast detect AF. Clearly in bright light on Program, it will retain a wide aperture to ensure AF, and select too fast a shutter speed for optimum 'look'. Even at ISO 50, f/3.5 is too wide. The solution is to use a neutral density filter on the lens. I have 4X, and also a variable one which I don't like. I need to have maybe an 8X as well. With the right ND filter, you can shoot on bright days and get optimum shutter speeds on Program. OK, it's not spontaneous, in the time it take to fit an ND you could switch your video mode.

But that is the answer to combining video with AF, with some control of the shutter speed. Invest in a low density variable ND, or two or three fixed value NDs.

David