VBR and file sizes

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Andrew
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HI guys, bit of a noob at the whole video thing, but am going on holiday later this year to Disney Florida, and am wanting to shoot plenty of video clips as well as the usual stills.

Still unsure what camera I will take I have the Panasonic G9 and EM1 MK II from Micro four thirds, or my Fuji X-T3 or X-H1, but in any case, I'll be shooting 4k 25 (maybe some 4k 50 on faster action etc). but am now looking as to what size cards I'll need, how fast and how much footage I'd get on them.

My G9 (i think) limits VBR to 100-150mb/s, the EM1 MK II about 100 mb/s, the X-H1 a max of 200mb/s and the X-T3 upto 400mb/s (but most likely for home video clips on the Fuji's, I probably won't set it any higher than 100-150mb/s). Is there a calculator or the like somewhere that would tell me for the various bit rates how much storage per minute (or hour) it would likely eat up on the card, and what sort of speeds I should be looking at?

I know a lot will say get the fastest card possible, but if I can get away with a slower card -for instance a Sandisk 95 Extreme Pro 128gb, then the price difference between that (currently £30 on Amazon) vs the UHS-II 300mb/sec version (£230.00 on Amazon today) is absolutely huge. The Sandisk 95's are UHS-1 but V10 and U3 rated, (so from what I've read they should handle 4k no problem) ?

Thanks for any help.
 
If you take 100 Mb/s as an example:

100/8 = 12.5 MB/s

12.5 x 60 x 60 = 45000 MB/hour = 45 GB/hour

There's a slight difficulty in that flash memory quite often uses a factor of 1024 instead of 1000 to calculate size, but this will give you a decent ball park figure.
 
Why not get a dedicated camcorder? I have A Panasonic HC-X900M no longer in production but a fantastic video recorder. Panasonic or Sony are the ones to look for, they now are quite cheap as well at the bottom of the range. One advantage they are not time limited as DSLR cameras . The camcorders are small enough even to fit into a jacket pocket. I have taken mine to many countries over the years and the zoom range is really great as well.
One of the big problems is wind noise

I did a test without and second half(0.18 sec in) with a muffler "deadcat" over the external mike.

View: https://www.youtube.com/watch?v=mvEkZ_S3V7o


One problem with using a DSLR for video is having to adjust the focus while videoing and putting on the right lens, a camcorder gets over this as it will auto focus.

View: https://www.youtube.com/watch?v=WQI23VmWeCc


Another thing to consider is sound quality, with my Nikon camera if using auto focus I get a loud click as it auto focuses , not what one wants

This is my setup for video work

gsVSMqK.jpg


Camcorder as mentioned above

SennheiserMKE400 ( sound quality is excellent)
Deadcat (muffler) Gutmann (has longest fur I could find to cut wind noise)
spacers to keep deadcat away from showing in video
SD card 32gb (v30) is what I use
mini flexable tripod ( handy for table top use)



A lot of mike's have a sponge type muffler, I found they were totally useless after trying a couple out.

Of course if shooting indoors you will also need a steady LED light and end up with something like this with the LED light on an extended bar
R9wfYot.jpg

May look odd but actually makes a good hand hold to keep it all steady.

Please ask if you have any questions Andrew
 
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