46 (edited by Chas Tennis 2016-Jun-13 12:57:27)

Re: Basic High Speed Video Camera Considerations & Cameras

Recent website that specializes in high speed video cameras. 
http://hispeedcams.com/

It is always easy to find the frame rates and resolutions for high speed video.

It is usually more difficult to find information on:
1) whether automatic exposure control or manual exposure control
2) shutter speeds and resulting motion blur
3) total recording time - some cameras record for just a few seconds
4) Jello Effect distortion
5) other specifications and features that may be important for some applications

I just started reading some of the camera reviews. The reviews seem to have more information on the above subjects.
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UPDATE - 2016-Jun 10. After a year, I've been a little disappointed in the information presented for these reasons:
1) A considerable percent of the camera reviews relate to rumors or claims concerning capabilities that a camera may have in the future instead of to cameras now available with those capabilities.
2) I suggested review of the Casio Ex f100 with manual exposure control but learned that it does not have high enough resolution in high speed video mode to qualify for a review.  Certain very capable high speed video cameras may not be reviewed because of resolution.
3) For video analysis the issue of motion blur is very important, but I'm still not able to find shutter speed information.  Typically, review videos are not presented that display motion blur very well. 

The site is still outstanding for showing many new cameras with higher resolution in high speed video modes.   

But for analysis some very capable cameras with manual exposure control or automatic exposure control for very fast shutters and zoom lenses may not be reviewed because of hispeedcams's resolution cutoff policy.

47 (edited by Chas Tennis 2016-Jun-04 14:29:22)

Re: Basic High Speed Video Camera Considerations & Cameras

Casio Ex 100f - the user's manual indicates that the camera has manual exposure control and a 1/10,000 sec shutter speed. 

I have no experience with this camera.  I have not found Ex 100f user's high speed videos on Youtube to evaluate the shutter speed and motion blur.   

I first heard about the Ex f100 in a dpreview thread. I missed the first announcements in Aug 2015, as a model available in Japan.  See subsequent posts following this post.
http://www.dpreview.com/forums/post/57666381

An Ex 100f user's manual is available from Casio Support:
http://support.casio.com/storage/en/man … 116_EN.pdf

For high speed video and manual shutter settings, the user's manual has this -

Quote -
"Using BEST SHOT Use the procedure below to shoot a High Speed Movie with manually configured aperture and shutter speed settings. The ability to manually adjust shutter speed helps to reduce image blur due to subject movement.

1.In the BEST SHOT Mode, select “Manual Exposure Movie” (page 93).

2.Press [SET].

3.Use [8] and [2] to select (Aperture) and then press [SET].

4.Use [8] and [2] to select an aperture setting and then press [4].

5.Use [8] and [2] to select (Shutter Speed) and then press [SET].

6.Use [8] and [2] to select a shutter speed and then press [SET].

7.Press [0] (Movie) to start recording.

8.Press [0] (Movie) again to stop recording.

The maximum file size allowed for a single movie file is 4GB. Movie recording stops automatically when the file size becomes 4GB.

NOTE• The settings below can be configured while shooting with this function.

Movie Quality: HS120, HS240, HS480, HS1000

Shutter Speed: Auto, 1/125 to 1/10000 seconds(The actual available setting range depends on the movie quality setting.)

ISO Sensitivity: Auto, ISO80 to ISO3200(The actual available setting range depends on the shutter speed and aperture.)•

The functions below cannot be used with this functionAnti-shake Functions, Single SR Zoom, Face Detection, Make-up, Triple Se................."

"HS1000
(224x64)
(1000 frames/second)
13 minutes 10 seconds

HS480
(224x160)
(480 frames/second)
13 minutes

HS240
(512x384)
(240 frames/second)
12 minutes  58 seconds

HS120
(640x480)
(120 frames/second)
12 minutes 55 seconds"

Information on this camera is not easy to find. Using "100f" helped my search.  If you find some Ex 100f Youtubes that display high speed video modes and motion blur (no splashing water videos please) please post.  If you have an f100 please test it in high speed video mode with fast shutter speeds and post some of your videos.   Motion blur info please....

Also, the Jello Effect distortions of this camera need to be evaluated.

(The Ex 100f camera may be related to another Casio model, the Ex 100pro discussed in an earlier post, #44. Apparently a false alarm as first there were announcements in Dec 2014 and then nothing. ? I have not found farther information, on shutter speed, etc. of the high speed video modes of the Ex 100pro camera. (Only Casio-produced high speed videos were shown, no user's high speed videos seem available.)   

The Casio Ex 100f camera is offered on Amzn.

Re: Basic High Speed Video Camera Considerations & Cameras

This looks pretty promising!

Re: Basic High Speed Video Camera Considerations & Cameras

Here is a video of the casio ex-100f @240fps and shutter 1/10,000

Re: Basic High Speed Video Camera Considerations & Cameras

Cool. Thanks for posting!

That's a lot of light for a 100µs opening, that's good, was it a very sunny day? It also seems you are facing the sun which would help with the short aperture time. The dynamic range doesn't seem super high though. I wonder the amount of light required for indoor filming.

The rolling shutter distortion is visible on the club on the way down.

Do you still have the raw file straight from camera and could you upload it somewhere? I'm wary of YouTube compression artifacts. We can also host it here if it's not too large.

Do we know what sensor this device is using?

51 (edited by Chas Tennis 2016-Jun-27 14:24:31)

Re: Basic High Speed Video Camera Considerations & Cameras

I find this information especially useful for examining Youtube and Vimeo videos and estimating the light levels that the videos were shot in.  This approach especially helps estimate the unknown fastest shutter speeds in direct sunlight for video cameras with automatic exposure control.  The motion blur is an indication of the shutter speed.

You can see some things from the shadows in pictures.

1) the shadow of the drink.
2) the shadow of the golfer.
3) the tree line illumination.

In post #49, the sun is behind the golfer.  The drinking cup shadow gives a more accurate indication of where the sun is.  The sun also does not shine on the tree line. 

But the club itself goes in and out of the golfer's leg shadows so various illuminations from direct sunlight to indirect occur. (I believe that illumination in most shadows is called 'skylight' and there's always some other miscellaneous reflected illumination.)  The golf club can be seen in the leg shadows.

Sunlight vs Skylight. See section 2.1
http://web.stanford.edu/group/narrative … design.pdf

The edges of the shadows are sharp. I interpret sharp edges to mean that the sun light is not diffused by overcast skies.

The golf club is painted black and has a smooth surface.  At parts of the swing, I believe you can even see a specular reflection of the sun from the smooth cylindrical surface on the top of the club and black on the bottom of the club. 

Regarding low light capabilities, for my Casio FH100, the camera can expose at 1/40,000 sec on a sunny day and still get an adequate exposure in the shadows (from skylight and other reflections). 
https://vimeo.com/26480215

Overcast skies provide less light but often still enough for very fast shutter speeds, 1/5000 sec?,  with the Casio Ex FH100 and maybe the Casio Ex 100f also. ?

Indoor lighting of tennis courts has a light level only about 1% of direct sunlight.  Those light levels are from published data and are discussed in a post earlier.  Shutter speeds of 1/1000 sec may not have enough exposure.
http://www.kinovea.org/en/forum/viewtop … 2033#p2033

I examined the 100f video file on my computer and it looks better than the Youtube version.  That is usually the case also with my low resolution Casio FH100 videos on Vimeo.  I don't know if the small loss in quality is the Youtube or Vimeo compression or pixel count changes in the format's number of pixels.  I like Vimeo because it advances single frame on Vimeo without downloading. 

Use direct sunlight if you can!

Re: Basic High Speed Video Camera Considerations & Cameras

Thanks for providing the straight-from-camera files. Here are the links:
- ex100f-1.avi. 240fps, 1/10000, 512×384px. (8.17 MB).
- ex100f-2.avi. 480fps, 1/10000, 224×160px. (7.36 MB).