highest gain before you see grain?

Tom Roper said:
Regardless of the Z1's reputation (which I owned) for shooting with gain-up, the Ex1 is in another class. The EX1 is much better at shooting low light video with low grain. There's more sensitivity probably a 0 gain than the Z1 had at +12 (or more).
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Yes, the believe the native ISO of the sensor in the Z1 was much lower than the 400 of the EX1. Does your EX1 handle +6b and +12 of gain as well as the Z1?

basspig said:
While the EX1 is also cleaner, another factor to consider is that the XDCam CODEC handles noise much better than HDV CODEC, which tends to produce an ugly blocky artifact with the noise from HDV cameras. You could have lots of noise and the XDCam CODEC would still look like film grain, not macroblock noise. That said, the reduced noise of the XDCam EX makes the matter a non-issue.
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I understand that XD Cam EX looks better than HDV, that DVCProHD looks quite a bit cleaner still. But the look of gain is still an issue for me in the even with DVCProHD. In your experience, does the EX1 handle +6db and +12db of gain about like the Texas Shootout screenshots of the Z1 show? Better? Worse?

Thanks.
 
The XDCam CODEC looks pretty darned indestinguishable from uncompressed, unless doing green screen work with fast-moving subjects. DVCProHD is just less efficient and uses more bandwidth with the only advantage that older computers could edit it with less struggle than longGOP MPEG. Definately, you can go to +18dB gain and it still looks good. It starts to resemble film stock that's been 'pushed' with a slightly harsher edge, but for anything but filmmaking, most shooters consider it acceptable.
 
basspig said:
...Definately, you can go to +18dB gain and it still looks good. It starts to resemble film stock that's been 'pushed' with a slightly harsher edge, but for anything but filmmaking, most shooters consider it acceptable.
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Thanks for your reply. I'm not sure if I wrote my question clearly. Would you say that, with +12db, the EX1 looks more like

this (HVX200) http://www.dv.com/dv/magazine/2006/June/TX-18-HVX200.jpg

or this (HVR-Z1) http://www.dv.com/dv/magazine/2006/June/TX-18-Z1.jpg
 
Those images look terribly soft. In fact, they look like standard def, upscaled. I shot some +12 and +18 scenes and, though there is the very slightest fine grain visible in the black areas with no picture profile active, the images are sharp and clear enough to see fibers in the fabric objects I used in the scene.

The +12 actually looks very nice. It's not soft and blurred like those two examples you posted. In fact, I had to apply PhotoShop "Blur More" TWICE to reduce the edge detail to match that of the Z1U image. The EX3 image looks like 400ASA film whereas the Z1U looks like plain old NTSC video. Without being able to shoot the same exact scene with all three cameras, it would be hard to make a comparison that everyone could agree on. It's possible that the sharpness was turned all the way down on those test images to minimize noise, but at great cost of details.

Maybe I'll test again, with turning the detail all the way negative, to see if softening the image makes the residual noise totally invisible. But what good is clean if there's no detail? Those two frames don't even look like hi-def to me.
 
basspig said:
Those images look terribly soft. In fact, they look like standard def, upscaled. I shot some +12 and +18 scenes and, though there is the very slightest fine grain visible in the black areas with no picture profile active, the images are sharp and clear enough to see fibers in the fabric objects I used in the scene.

The +12 actually looks very nice. It's not soft and blurred like those two examples you posted. In fact, I had to apply PhotoShop "Blur More" TWICE to reduce the edge detail to match that of the Z1U image. The EX3 image looks like 400ASA film whereas the Z1U looks like plain old NTSC video. Without being able to shoot the same exact scene with all three cameras, it would be hard to make a comparison that everyone could agree on. It's possible that the sharpness was turned all the way down on those test images to minimize noise, but at great cost of details.

Maybe I'll test again, with turning the detail all the way negative, to see if softening the image makes the residual noise totally invisible. But what good is clean if there's no detail? Those two frames don't even look like hi-def to me.
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Many thanks for your detailed response. Re. the gain, I was wondering if it would even be possible to tell from those pictures, but they were all I knew to post. What I'm hearing from you is that the EX1 handles +12db pretty well. I guess this would be the equivalent of ISO 1600, which would be enough for my purposes.:happy:

Edit:
Just thought to post some pictures of entry level DSLR's (Canon XS and XSi) at ISO 1600. Wondering if the EX1 shows more or less grain at +12 of gain (around ISO 1600) as these DSLRs at ISO 1600?

http://www.digitalcamerareview.com/shared/picture.asp?f=21573

http://gallery.photographyreview.com/showphoto.php?photo=100014&size=big&cat=
 
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My two test frames look about like that, but with a bit whiter hotspots in the grain that appears on black areas. Grain is invisible on areas containing texture, such as fabrics.

And remember that you can increase the ISO without gain by shooting 24P and shutter off. I have heard it estimated at 800-1200 ISO under those conditions, with 0dB gain.
 
basspig said:
My two test frames look about like that, but with a bit whiter hotspots in the grain that appears on black areas. Grain is invisible on areas containing texture, such as fabrics.

And remember that you can increase the ISO without gain by shooting 24P and shutter off. I have heard it estimated at 800-1200 ISO under those conditions, with 0dB gain.
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This info is extremely helpful. Many thanks for your time.
 
Argh, say no to 360º shutter! Unless you want someone to look like a ghost when he's moving.
 
My default settings are -3, 0, +3 too. I don't like to go over 6 if possible, and if it's a matter of getting the shot or nothing at all, I'll crank it as high as it needs to be. There are times when it's real dark I'll just hit "Full Auto" just to capture something, although at that point it's not paid footage, just family stuff or something. Most recently I did this while walking with my family checking out Christmas lights in the neighborhood... I'm sure it went to 18 on Full Auto but it's certainly still watchable and captured some good memories.
 
You must live in a very dark neighborhood. If I used + anything gain, I'd blow the highlights on the lighting displays.
 
I was going to suggest that you check the neighbors light displays for low voltage. :)
I have never heard of using gain up to see Christmas light displays. I'm usually about F4 with -3dB gain and the scene is STILL overexposed.
 
basspig, maybe we're talking apples and oranges... I'm not actually shooting just the displays, as in close-ups or documenting them. The example I gave with the Christmas lights was more of walking at dark down neighborhood sidewalks with my wife and kids as we enjoyed some cool light displays. You can't even hardly make out my kids silhouettes at -3dB in the dark much less capture watchable footage. I was shooting to see their expressions (they're toddlers) more so than just the lights. Although I did shoot some lights too, but the Full Auto obviousy compensates the iris when I shoot at lights.

Another example of having to use really high gain was while exploring a natural cave with my boy that was very dimly lit. Same when we went tricker treatin' on Halloween. Even at 18dB it's still pretty dark footage, and quite noisey but better than nothing at all. If I had used 6 dB you would not be able to see anything watchable. Of course these are all handheld shots just hangin' with the fam.

When I could I used my Micro Panels lcd on-camera lights on their faces but when there are lots of people around it's annoying for them to have some guy pointing bright lights all around, ha!
 
That's a difficult kind of shoot. You either have to let the point light sources badly blow out or get dark facial footage. I had that challenge filming my family sitting on the tailgate of our truck while waiting for the fireworks to begin last July. Solution was to use SLS with 2 frame accumulation. That seemed to provide nice grain-free imaging, though it was a bit TOO much as the glow necklace my daughter was wearing came out overexposed. But it lit her face nicely and made for interesting shots.
 
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