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ISO Rating on XDCAM HD F350


Roderick A. Santiano

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Tomorrow is day 7 of our 7 day shoot with two XDCAM HD F350s. We had almost no time to prep and experiment with the cameras so I've been trying to figure out an interesting ISO rating situation but haven't been able to crack it. I've been shooting with the gain settings at -3db as I've always done with the Varicam. But I've come up with an ISO rating of 80. Kinda low for HD shoot don't you think? There is virtually zero noise in the shadows compared to the same settings when shooting with Varicam.

 

I'm very pleased with the images I've been getting so I'm not necessarily complaining here since I've been able to get enough light going in the studio for this shoot. I'm just wondering why this camera has such a low rating compared to other HD cameras. Does anyone know anything about this? I haven't once had the luxury of having a DIT on any shoot so I don't really know for sure if there's something I'm missing/doing wrong or what not. Any information will help.

 

Oh, another thing: I've also been using the "CINE3" gamma setting. I love the look, although I'm completely in the dark as to the actual specs of this setting--I just know it looked the best. Does anyone have any information on the gamma settings for the F350? (STD, CINE1, CINE2, CINE3 and CINE4)

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  • 3 weeks later...
Tomorrow is day 7 of our 7 day shoot with two XDCAM HD F350s. We had almost no time to prep and experiment with the cameras so I've been trying to figure out an interesting ISO rating situation but haven't been able to crack it. I've been shooting with the gain settings at -3db as I've always done with the Varicam. But I've come up with an ISO rating of 80. Kinda low for HD shoot don't you think? There is virtually zero noise in the shadows compared to the same settings when shooting with Varicam.

 

I'm very pleased with the images I've been getting so I'm not necessarily complaining here since I've been able to get enough light going in the studio for this shoot. I'm just wondering why this camera has such a low rating compared to other HD cameras. Does anyone know anything about this? I haven't once had the luxury of having a DIT on any shoot so I don't really know for sure if there's something I'm missing/doing wrong or what not. Any information will help.

 

Oh, another thing: I've also been using the "CINE3" gamma setting. I love the look, although I'm completely in the dark as to the actual specs of this setting--I just know it looked the best. Does anyone have any information on the gamma settings for the F350? (STD, CINE1, CINE2, CINE3 and CINE4)

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It's a nice camera, but remember that it is a 1`/2" sensor not a 2/3" like the Varicam. And it's 180 not 720. That means that each pixel is smaller on the 350. The smaller the physical area of the pixel, the less light it can gather. So it is less sensitive (by about a stop) because of simple physics.

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Thank you, Mitch. I kinda wish I read your e-mail about half an hour ago. I just found out before checking in on this forum, like you said, that the F350 is one stop slower than the F900. Shooting at -3db adds the extra stop loss, therefore giving me a rating of 80 ISO. Mystery solved, thank you for your help!

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Thank you, Mitch. I kinda wish I read your e-mail about half an hour ago. I just found out before checking in on this forum, like you said, that the F350 is one stop slower than the F900. Shooting at -3db adds the extra stop loss, therefore giving me a rating of 80 ISO. Mystery solved, thank you for your help!

 

 

The f350 has 1440x1080 pixels in 1/2 inch sensor vs 1920x1080 pixels in 2/3 inch f900.... so what is the actual difference in size of pixels?

 

 

Mike Brennan

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  • 3 weeks later...
  • 1 month later...
Oh, another thing: I've also been using the "CINE3" gamma setting. I love the look, although I'm completely in the dark as to the actual specs of this setting--I just know it looked the best. Does anyone have any information on the gamma settings for the F350? (STD, CINE1, CINE2, CINE3 and CINE4)

 

The STD gamma on the XDCAM HD's is fairly linear with a hard white clip. The contrast range you can capture with STD is quite limited.

 

The Cine gammas capture a much higher contrast range and all have a nice highlight roll-off. Cine 2 captures the widest range (400% range I think), and naturally rolls off before 100ire. It gives very flat look that needs correcting in post. But you will be amazed at how good it is when you are faced with an interior shot against a bright window!

 

The other Cine gammas go above 100ire and capture less of the range the CCD's are capable of. Of these Cine 4 is the closest in look to the STD gamma, but gives you just a bit extra range to work with and a nice highlight roll-off. Cine 1 is a good average one to use. It stretches the mid-tones less than Cine 2 but more than the others. Cine 3 gives a subtle stretch to the mid-tones.

 

So you could say that Cine2 is the one you want to use for maximum range with a post grading process for filmlook (combined with proper detail and aperture correction setup), Cine 4 is good for normal shooting.

 

Looking at the curves I would NOT recommend that you mess around with the knee and knee slope with Cine 2. From what I can tell it is already giving you the maximum contrast range the CCD's are capable. I would also be hesitant to use DCC with this (the DCC on the XDCAM HD tends to 'jump' mid-shot anyway, so best to leave it off).

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  • 2 weeks later...
Are you sure? AFAIK the 900 is 1920x1080. Its just that what gets laid down to tape is 1440x1080.

 

Huh..? So, what I have on my tapes is 1440x1080? I've never heard of this. I want to say it's still

1920x1080. If it's 1440x1080, it wouldn't be any close to 16:9 at all.

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Huh..? So, what I have on my tapes is 1440x1080? I've never heard of this. I want to say it's still

1920x1080. If it's 1440x1080, it wouldn't be any close to 16:9 at all.

 

No, not true. It wouldn't be 16:9 if it was based on square pixels, but it isn't. It has a pixel aspect of 1.33. HDCAM SR records the full raster 1920 x 1080. However HDCAM does not.

 

Its the same with the Varicam. 1280 downsampled to 960.

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  • 11 months later...
Tomorrow is day 7 of our 7 day shoot with two XDCAM HD F350s. We had almost no time to prep and experiment with the cameras so I've been trying to figure out an interesting ISO rating situation but haven't been able to crack it. I've been shooting with the gain settings at -3db as I've always done with the Varicam. But I've come up with an ISO rating of 80. Kinda low for HD shoot don't you think? There is virtually zero noise in the shadows compared to the same settings when shooting with Varicam.

 

I'm very pleased with the images I've been getting so I'm not necessarily complaining here since I've been able to get enough light going in the studio for this shoot. I'm just wondering why this camera has such a low rating compared to other HD cameras. Does anyone know anything about this? I haven't once had the luxury of having a DIT on any shoot so I don't really know for sure if there's something I'm missing/doing wrong or what not. Any information will help.

 

Oh, another thing: I've also been using the "CINE3" gamma setting. I love the look, although I'm completely in the dark as to the actual specs of this setting--I just know it looked the best. Does anyone have any information on the gamma settings for the F350? (STD, CINE1, CINE2, CINE3 and CINE4)

 

I've rated the camera at a 250asa @ 24fps.

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  • 1 year later...
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One thing to know is you can't make a 1 to 1 comparison of gain settings between manufacturers. They are arbitrary numbers that mean little when saying I have a Sony that is 0 and a Panasonic that is set at 0. Both cameras give a completely diferent picture at 0.

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