Z1U - How to translate gain into ISO

[Hans van Turnhout]

I will be doing a two camera shoot with very different cameras (HVR-Z1U and Nikon D4) and I'm trying to set these up to be as close as possible and exposure and white balance is key. As there is no histogram on the Z1U I will have to rely on my lightmeter to set the proper exposure (no I don't trust my own eyes that much). I understand that the iso of Z1U is 160 (Four Affordable HD Camcorders Compared) but what will be the corresponding iso if I dial in 3db, 6db, 9db etc gain?

Regards

Hans

[Chris Harding]

Hi Hans

Every 6db of gain you add doubles the ISO so +6db = 320, 12db = 640, 18db = 1280, 24db = 2560 and 30db = 5120 ISO You will of course have to decide how much video noise your Z1 will generate at various gains/ISO's ... some are clean up to 24db and some are just awful ... the D4 will probably produce a much cleaner image at 5000 ISO than the Z1 can at +30db so you will have to take that into account.

Chris

[Hans van Turnhout]

Thanks for the speedy reply. I've done some testing and compared the footage between the two cams and even with exposure and WB correctly set there is great differences in color and saturation. Next step will be to try to dial in picture profiles that are as close to one another as possible. Any insight in this regard?

Regards

Hans

[Don Bloom]

I doubt you will ever get them to match 100%, maybe not even 75%. The Z1 is an older camera, still a good one but an older model and the DSP of the camera is old. Also it's 3- 1/3rd inch CCD vs whatever the D4 is using. I'm not trying to be a downer but if you can get them to within 50 to 75% of one another be happy and "fix the rest in post". I can't believe I just said that but IMO that's about the only way you'll get the 2 cameras to get anywhere close to a match.

[Hans van Turnhout]

Yes, I'm afraid that's the case but it's worth a try since it would be nice to mix different angles etc of the dancer doing her dance. It's something we are doing just for fun so it's not the end of the world if it doesn't turn out 100%.

Regards

Hans

[Chris Harding]

Hi Hans

It will probably be better to try and make the shots from each camera as different as possible ..so use the Z1 say, as a far back wide angle shot and then use the D4 for closeup shots so the shots physically don't need to match as close as if you had one cam to the right and one to the left both at the same framing..switching then would show up matching differences a lot more. I saw a wedding shot on two un-matched cameras and the guy used the same sort of framing and it really looked bad ...I shoot with my Sony's (matched cameras EA-50's) at weddings and I also use a little GoPro high up on a stand to provide a "semi-aerial" shot. Because the angles and framing are drastically different from the Sony's you don't notice any slight colour difference.

Chris

[Hans van Turnhout]

Chris,

Thanks. I'll make the shoots as different as possible and also make use of my GoPro mounted high. If it turns out to bad we'll keep them separated instead of combining them into one.

//Hans