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#1 Delorme Jean-Marie

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Posted 28 September 2005 - 04:00 AM

hi
on the specs this cam has an asa rating of 800 asa
what asa rating do you find on your agdv
without filters
with 1/8
with 1/64?
thanks
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#2 Sampsa Huttunen

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Posted 07 November 2005 - 12:16 PM

hi
on the specs this cam has an asa rating of 800 asa
what asa rating do you find on your agdv
without filters
with 1/8
with 1/64?
thanks


As far as I know, the asa rating without any gain is 320.
Haven't tested with filters, but 1/8 should be -3 stops and 1/64 -6 stops.
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#3 Vinod Raja

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Posted 02 December 2005 - 03:22 AM

As far as I know, the asa rating without any gain is 320.
Haven't tested with filters, but 1/8 should be -3 stops and 1/64 -6 stops.



Hi ! I rate the camera at 500 ASA without ND filters, 64 ASA with 1/8th ND. Arrived at this speed using my pentax digital spot meter on a 18% grey card to match the readings with my Minolta autometer III.
Thanks best
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#4 Phil Brown

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Posted 20 December 2005 - 05:06 PM

ASA for DVX100

DVX100 guru Barry Green writes a great chapter on this in his "The DVX Book" a great tool for any DVX owner.

There is a lot of technical analysis and he lists the testing conditions - well worth reading. Testing was verified with a sekonic L-508C lightmeter in spotmeter mode, and a waveform monitor to guage camera response.

The general conclusion is that the DVX100 is variable but as a general guide, rate the camera at 640ASA in progressive and 1000ASA in interlaced mode and you will be within 1/2 stop of being accurate (diff between 400ASA and 640ASA is 1/2 stop and from 640ASA to 800ASA is about 1/4 stop).

Available light will cause variations - at f/2.8 progerssive he tested 400ASA in progressive and f/16 800ASA (and 1280ASA interlaced)

so... 640ASA progressive is a pretty safe call for most situations - if possible use DV Rack on a calibrated monitor or laptop to really see what the camera is recording.

Hope this helps.

Phil Brown
Video Production Melbourne
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#5 Laurent Andrieux

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Posted 13 January 2006 - 03:26 AM

diff between 400ASA and 640ASA is 1/2 stop and from 640ASA to 800ASA is about 1/4 stop


Sorry, it's 1/3 of stop difference in both cases...
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#6 Jamie Metzger

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Posted 19 January 2006 - 04:11 PM

ASA for DVX100

DVX100 guru Barry Green writes a great chapter on this in his "The DVX Book" a great tool for any DVX owner.

There is a lot of technical analysis and he lists the testing conditions - well worth reading. Testing was verified with a sekonic L-508C lightmeter in spotmeter mode, and a waveform monitor to guage camera response.

The general conclusion is that the DVX100 is variable but as a general guide, rate the camera at 640ASA in progressive and 1000ASA in interlaced mode and you will be within 1/2 stop of being accurate (diff between 400ASA and 640ASA is 1/2 stop and from 640ASA to 800ASA is about 1/4 stop).

Available light will cause variations - at f/2.8 progerssive he tested 400ASA in progressive and f/16 800ASA (and 1280ASA interlaced)

so... 640ASA progressive is a pretty safe call for most situations - if possible use DV Rack on a calibrated monitor or laptop to really see what the camera is recording.

Hope this helps.

Phil Brown
Video Production Melbourne



That Helped me. My friend was rating it at 800, which isn't far off, but I'd rather go with 640.

Thanks.
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#7 David Mullen ASC

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Posted 19 January 2006 - 04:13 PM

I found the original DVX100 at 24P to closer to 320 ASA at 0db with a 1/48th shutter.
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#8 Laurent Andrieux

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Posted 20 January 2006 - 03:18 PM

Sorry, it's 1/3 of stop difference in both cases...


I realize I made a mistake, though I can't edit..

it's 2/3 of a stop beetween 400 and 640 and 1/3 beetween 640 and 800, sorry
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#9 G McMahon

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Posted 08 August 2006 - 10:04 AM

I?m shooting at the moment with this camera. I am finding this time it is really sucking up the light. I admit, I never have shot it with the shutter on before but I didn?t think I would need as much light. Does certain scene file options steal more light than others or I am more light conscious now?

G.McMahon
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#10 Phil Brown

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Posted 08 August 2006 - 10:59 AM

I?m shooting at the moment with this camera. I am finding this time it is really sucking up the light. I admit, I never have shot it with the shutter on before but I didn?t think I would need as much light. Does certain scene file options steal more light than others or I am more light conscious now?

G.McMahon



Yes, some scene files do have settings that reduce response to light F5 & F6 progressive settings particularly.

The DVX100 is not a good choice in low light - I have been frustrated by it many times and seen $600 handycams blow it away - but with light of course, it's magnificent. You can try using video gain settings to improve light tresponse, but remember, you will increase the grain considerably.
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#11 Andy Lehmann

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Posted 15 August 2006 - 11:25 AM

The ASA rating is something between 250-320 ASA (with cinegamma on and in 25p mode).
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