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airsideservicesltd.
01-20-2008, 09:37 AM
Our Tech at particular military est notes that the topic of frame rates occurs frequently.

We scan these forums for viewer feedback to benefit our knowledge base.

Please do not forget that video framerates in comparison to pc "screenshot" frames do differ.

A screenshot is a completely perfect image, a crisp snapshot, if you will.

A singular video/film/camera frame has blurring due to movement.

25 video frames does not equal 25 pc screen frames.

We notice slight flicker fusion frequency at 29 frames or below in microsft's flight simulator 2004. This choppiness is not a percieved flicker, but a perceived gap between the object in motion and its afterimage left in the eye from the last frame. A computer samples one point in time, then nothing is sampled until the next frame is rendered, so a visible gap can be seen between the moving object and its afterimage in the eye.

Cameras allow images to be interpolated together due to almost continuous light entering the shutter, this leads to a small amount of motion blur between one frame and the next which allows them to transition smoothly.

So please be aware that the industry wide acceptance of 25 frames for smooth visuals is not correct. There will still be some stutter closer to the eyepoint...ie lower on the screen. Particularly noted if using a projector to assume forward view in a home simulator.

A better frame rate is closer to 30 in fs. The magic number of 25 frames in fs is simply incorrect.

Andre Anderson
AirSideServicesAusPtyLtd.

Matt Olieman
01-20-2008, 11:52 AM
Andre, I think most of us will agree with you. But knowing the limitations of our computers, we seem to accept 22 to 25 fps.

I'll take 30 fps any day, if I can get it without a stutter, it just seems when we push the frame rates up, we end up with other problems, like the stutter.

This is a hot topic :) Because we strive for those high frame rates :) :)

Thanks for your input Andre :)

Paul G
02-01-2008, 07:59 PM
I'll take 30 fps any day, if I can get it without a stutter, it just seems when we push the frame rates up, we end up with other problems, like the stutter.

I set my sim at 18 fps. Sure I could probably get higher but I find this adequate considering I have a load of beautiful add-ons that make the experience so realistic.

My best buddy is also a sim nut, but he's on the x-plane platform. He's updated his system to the point that he's getting 60 frames per second, and he says mine is just too slow. I find at 60 fps, it's almost surreal. Although i could live with it, I find it more artificial, especially with rapid movement where there's no blur. A bit like filming with a video camera, setting the shutter speed to a high value. You lose sense of reality, as if everything is on it's own layer.

Isn't it just about 2 things; 1. Finding a balance, and 2. Getting used to a performance setting?