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John_Cillis

Frame rates

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Im not sure I understand the whole concept of frame rates. I mean, I get that 25 fps is fewer frames per second than 30, and thats likely smoother than a slower setting. I know how to set target frame rates in MSFS 2k2, but Im not really sure what the hit is if you just peg the slider as high as it can go. Why wouldn't everyone do that?

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I think the idea is to get a fairly constant frame rate, ratherthan one that is at 40 FPS, then suddenly "studders" down to 5-6,then returns back up again.scott s..

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When talking about FS2002, setting the fps slider to max takes resources away from texture drawing....textures had a greater tendency to blur over time 'coz the cpu was going full bore at cranking out the fps. Lowering the slider to somewhere below your average performance allowed the sim to better manage texture loading. In my case, my average performance given my sim settings in FS2002 is around 30 fps, so I lock my fps around 25, which I'm quite happy with...FS2004 is completely different it seems. The fps slider seems to cause at least some systems issues when textures are drawn. Some have found setting it to unlimited improves texture updates. It's almost as if the sim doesn't want to be bothered with silly little things like fps locks, or is so bothered that it loses step with other tasks.Computer animation and film animation come up often here in these discussions. Film animation makes the world look fluid with fewer fps. Since film animation is a series of still snapshots, artifacts of motion such as blur creep in which help our brains accept lower fps. In the case of computer animation where the frames are rendered dynamically, subtle differences occur and are detectable in fluidity in 50,60, even 70fps range. But I'd argue that 50fps doesn't seem twice as fluid as 25fps--only that it seems perceptibly better and that my senses find 25fps a good compromise.In the end, something already pointed out is what's most important. Microsoft's original documented explanation for the fps slider was to reduce the peaks seen in fps, so the valleys wouldn't hit our perception quite so hard. Someone humming along at 40 fps will notice a difference if the latest 30,000 poly AI aircraft sneaks into the scene and lowers fps to 20.... That difference is sometimes called stutter, sometimes hesitation--whatever. Having the fps slider set lower will fool your brain into thinking the fluidity is there...it evens out the peaks and valleys....Hope this long answer helps.... :)

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>snapshots, artifacts of motion such as blur creep in which>help our brains accept lower fps. In the case of computer>animation where the frames are rendered dynamically, subtle>differences occur and are detectable I know this argument pops sometimes in different threads but I personally have very hard time to accept that tiny blurriness in real motion pictures somehow improve things for human brains. The fact that those 'artifacts' of motion depend on actual exposure time (which often is much shorter than 1/25 sec) makes it even harder for me to swallow the whole argument. Unless I see definite studies on the subject performed by reputable organization I put it in the realm of another myth.Michael J.http://www.reality-xp.com/community/nr/rsc/rxp-higher.jpg

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Call it what you want, but there is indeed a difference in fluidity if you lock down any sim to movie/tv standards. Some can perceive it, others can't. I do a fair amount of photography, and unless movement is nearly still, I have to get the shutter speed into the 1/100th-1/250th of a second range before I can capture objects with moderate movement, like a man walking or leaf falling, with no blurriness in the person or object. And zoom in even closer, and the shutter speeds have to be even higher. On my digital movie cam, if I go frame by frame through a video, there is always some blur in any moving object. Back to MSFS--in my case, I'd rather dump the eye candy and have full control and "feel" of my aircraft vs. accepting fps in the below 20 range, as some do. What's great about our hobby is it has progressed to that point where we have a choice. I've simmed since FS-II and I well remember the lag factors that were programmed into the sim so the 4-8 fps updates didn't fall out of step with the controls... Nowadays, we can literally program our sims to run at 60-70 fps with infinite more detail than those sims of old...

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The prior post sums it up nicely- its all about keeping your frames (ie what you see on screen) coincident with your control inputs. FPS of 25-30 will do this nicely, anything above is nice but probably not necessary, anything below and you will have unrealistic lag between inputs and screen updates that is noticable on approach and landing. If you want as realistic flight dynamics as possible on FS, make sure your frames stay above that level. Best,Joel

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For what reasons are e. g. I-Max and similar kind of movies produced with 50 or even more frames per socond? Beacause the human eye is able to see a difference between 20, 24, 50 or 100 pics per second, even in movies. When most movies are produced with 20 - 25 pics per second, than this is done, because less would clearly give the impression of "unsmoothness". More fps would make lots of more film material necessary, which means the production costs of movies would increase significally. Also the more pics per second the better cameras (expensive high tech high-speed-cameras) and projectors are required. Those are also the reasons, why I-Max movies are generally shorter than e. g. the typical Hollywood block buster movie is.Also the higher the speed is (means the more frames per sec. a movie has) the more "real" it seems to be. It looks sharper and more 3-dimenasional.So in conclusion, that a typical movie is produced with 24 fps does not proove that the human eye would not be able to percept improvements of higher fps. It only prooves, that less than 24 fps cause a not acceptable loss in quality.Wolfgang

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Most of you are on the right track! Frames per second as stated in previous posts is basicly how fast your computer and the sim produce the graphical frame to your screen. There are standards to video quality and performace based on this. In film i.e. When you go to a theater those 16MM films are produced and shot at at 24FPS STMP and Video i.e like a VHS or VHS-C is usually shot at 30FPS STMPCheck this article cliping out:The following addresses the differences in the video standards of television broadcasting. Television receivers require a source of field timing reference signals, or field rates. These signals tell the television receiver to be ready to receive the next picture in the stream of images. Early television sets used the Mains power supply frequency as this source. There are two good reasons. The first is that with the older types of power supply, you would get rolling hum bars on the television picture if the Mains supply and power source were not at exactly the same frequency. The second is that television studios would have had enormous problems with flicker on their cameras when making programs. There are two field rate standards used around the world, 50Hz and 60Hz. Those with 50Hz systems run at 25 frames per second, those with 60Hz run at 30 frames per second. Frames per second can be thought as how many times your television set refreshes the picture in one second. Today, 60Hz systems actually have a field rate of 59.94Hz (29.97 frames per second). This was changed with the introduction of color television. The difference between field rates is one of the biggest difference between standards. It is the reason why it is difficult to convert between standards. (Somehow you have to make up for the difference of 5 frames per second.) Other differences include the delivery and correction of color and the number of lines per frame. Additional differences between standards developed throughout the years with the invention of color television and digital broadcasting. A majority of 60Hz television systems use the NTSC system. When used in a broadcasting environment, color, specifically hue, can exhibit problems. (NTSC was dubbed the name Never twice the Same Color because of this.) NTSC in video and closed circuit television does not have this problem. This hue problem is caused by the color sub-carries phase of the broadcast signal. To battle this problem, a group developed the PAL (Phase Alternative Lines) system. In correcting this problem, PAL's sub-carrier phase reverses every other line. This reverse is to offset any problem that occurred with the previous line. In developing PAL, a field rate of 50Hz (25 frames per second) instead of 60Hz (30 frames per second) was used. A variety of PAL, known as PAL M was also developed out of NTSC. PAL M has many characteristics of PAL, but PAL M runs at 30 frames per second. Another system was also developed, known as SECAM (Sequential Couleur Avec Memoire). SECAM was developed in France as a political move and quickly adopted by the former Eastern Block countries and Middle Eastern countries to encourage incompatibility with western Europe broadcasting. SECAM used a field rate of 50Hz (25 frames per second) and 625 lines per frame. Over the last decade, MAC-based broadcasting has taken off for satellite broadcasting. Several different varieties exist. In Europe, D-MAC and D2-MAC are used, Australia uses B-MAC, and in North America, B-MAC60 is used. Additional digital compression formats have been developed over the past few years. This include the MPEG-2 format and QuickTime format which are used in satellite broadcasting and Internet broadcasting. MPEG-2 can also be encoded using a number of encoding techniques. Michael Gallaghergallagha@charter.net

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Good post Michael....I only caution unless you authored the article, in the least you need to credit the source/author and in the extreme, the copyright on the source may prevent you from posting any portion of it, or the article in its entirety. I always suggest posting links vs. pasting the text for that reason... And please forgive me if you wrote the article--if you did, I'd love to see it in its original context...-John

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