Can the ISO be changed in the DVX100A?

Unless, of course, you consider using ND filters a change is ISO - in which case you have the ability to lower the effective ISO. Or, in the case of the gain settings, you can effectively raise it. Between them both, you end up with quite a range.

Chris
 
Come to think of it... according to Barry's book (you should get his book - it's absolutely great) the ISO rating of the DVX100B can range from 400 ASA to 1280 ASA depending on which mode you are shooting in and how you select gamma curves. A confusing thing about the DVX is that they specify ND filters as filter factors, and gain in DB's - neither of which are the same as F-stops or film speed. The ND filters are fixed at 1/8 and 1/64. The gain settings can be set anywhere up to +12db for progressive mode or +18db for interlaced mode - which correspond to 4x and 8x respectively. This means that in progressive "film-like" mode you essentially have the ability to emulate anywhere from 10 ASA to a whopping 5120ASA (assuming a base-line ASA of 640). If you throw everything in there - changing gamma curves and shooting modes - the effective range goes from 6 ASA to 10240 ASA! The 100A numbers are a little different - but not by much.

Pretty impressive - huh?

Chris
 
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Oooh, cbrandin scores on me with my own words. Excellent! :thumbsup:

I was thinking strictly in terms of how digital still cameras allow you to modify the ISO, so I just gave the blanket "no" answer, but you've demonstrated several ways that you can still accomplish the effect of changing the ISO.

Yes, using the ND filter can effectively change the ISO lower. And yes, the gamma curve can change the perceived sensitivity. Using interlaced mode makes it a stop faster than using progressive mode. Using gain doesn't actually change sensitivity though; it does change the brightness of the image but it doesn't make the camera more sensitive to shadow detail.

Thanks for taking the time to point out all the options! :)
 
True, when you use gain to brighten an image it won't bring in new detail. But have you ever shot 1600 ASA film? Not to put too a fine edge on it - well... it looks really bad. I've never even heard of 5,000 ASA film, let alone 10,000 ASA. On top of that, the DVX lens can do an F-stop of 1.7 - which is a lens speed that most film guys would drool over. The DVX might have some disadvantages when it comes to shallow DOF etc... But when it comes to light gathering ability - I've never seen anything like it. Then again, I come from the still photography world - everything I know about motion picture stuff I've learned here.

Chris
 
I think gain sort of works like push-processing film. Brighter (or denser, for negative film), not much new detail, grainy (noise).

Chris
 
cbrandin said:
But have you ever shot 1600 ASA film? Not to put too a fine edge on it - well... it looks really bad
Click to expand...

Try Kodak's T-Max 3200. It looks great, but is a completely different experience.
 
I was thinking of color film when I said that. I guess you're right - with B&W you could make artistic use of the grain and contrast. My main point was that when you consider the light gathering ability of the DVX, and how people complain about noise at lower light levels - you still have those problems, maybe even worse, with film.

Chris
 
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