Gates HC-7 Housing: Field Report

For you guys with the HC7 Gates and manual white balance, what are you using to balance against? I got the white balance slate and flex arm from Gates, but it seems kind of bulky and in the way.

For you guys with the HC7 Gates and manual white balance, what are you using to balance against? I got the white balance slate and flex arm from Gates, but it seems kind of bulky and in the way.

I was using a white slate on clipped to my chest D ring. It has one of those bungie coils on it. When you hit the set MWB button, you have a few seconds so it gives me just enough time to grab the slate and put it in front...

If anyone is interested, here is a short clip in a native m2t files straight from the HC7 unprocessed. A crab with telemacro on. I'll have to double check when I get back home today if I used lights on that one.

http://rapidshare.com/files/32381246/Crab_Telemacro.m2t.html

You can download vlc player here if you don't have the Sony Picture Motion Browser software that comes with their cameras.

http://www.videolan.org/vlc/

No processing done on the clip although some post production contrast adjustment really makes a nice improvement.

Nice work there.

Hints:

1 Try to keep the camera still.

2 The shot is overexposed. (Open it up in EDIUS and look at it with the Vector scope, its like over 120%)

That why its a good reason to have the ablity to manually kick the exposure back in situations like that.

In general the HDV cameras will over expose thing as its taking a calculation on the average light comming in. 16.9 has a wider frame so it has more chance of getting the light calculation wrong than with 4.3.

You can get into the menu and kick back the AE setting by 1 or 2 will help when on auto.

But thats only if you want to be fussy

Nice work there.

 

Hints:

1 Try to keep the camera still.

2 The shot is overexposed. (Open it up in EDIUS and look at it with the Vector scope, its like over 120%)

 

That why its a good reason to have the ablity to manually kick the exposure back in situations like that.

In general the HDV cameras will over expose thing as its taking a calculation on the average light comming in. 16.9 has a wider frame so it has more chance of getting the light calculation wrong than with 4.3.

 

You can get into the menu and kick back the AE setting by 1 or 2 will help when on auto.

 

But thats only if you want to be fussy

good tips... actually I thought I had dialed down the AE as I was watching for zebra stripes... [edit: actually there are two zebra settings 70 & 100, which is more sensitive (ie catch overexposure earlier?]

As for keeping the camera still... easier said than done ... guess that comes with practice or slapping one of those tripods on...

there are two zebra settings 70 & 100, which is more sensitive (ie catch overexposure earlier?]

70 will show overexposure earlier than 100, though 70 will not mean it is overexposed - it means you are moving towards danger but will still have some room.

70 will show overexposure earlier than 100, though 70 will not mean it is overexposed - it means you are moving towards danger but will still have some room.

Thanks Drew, ah I just realized I had it set to 100

70 is more relevant to shooting people's faces topside, because if I remember rightly 70 is about the right level for human skin. 100 is more relevant to underwater use. But don't be too rigid about having every single part of the frame under 100 because if you have small harsh highlights that you can't avoid, and you bring these under 100, then the picture in general might get too dark. But you should avoid significant areas of the picture being over 100.

This video isn't too badly over-exposed, and at least the over-exposed parts are the sea-bed and not the crab itself. But it could do with being a bit darker and it has a slight red caste so you should reduce the red a bit.

I've attached readouts for it from my scopes in Sony Vegas. The first one shows the waveform displaying only "luminance". Things look worse in the 2nd pic when it's displaying "composite" and it goes upto about 114% but I don't understand exactly what the "composite" mode means. Apparently it combines the luminance and colour levels, but what exactly does that mean and what should the limit be? Anyone?

When I put a "broadcast colors" filter on that clip, it only brings the composite level below 100% if it's in "extremely conservative" mode. In "lenient" mode it just brings the luminance level down to 100% and leaves the composite level up over 110%.

Any good tutorials online for this subject?

Interesting stuff Nick. I agree about the lack contrast in that original clip. In fact, I played with some color correction filters, WB, contrast, black level, and found the image really pops compared to the original. A lot of that I think has to do with the amount of particulate in the water that day (which was actually pretty good compared to the usual low vis we get around here!).

Man, I guess I really should have read the manual on my first trip with the HC7! Oh well, guess I'll just have to get back in the water soon to try out some new techniques. Thanks for the tips!

To darken up the silver of the HC7 barrel that was showing up thru my SWP25, I used a Sharpie Rub-a-Dub Laundry Marker. I only needed to cover the inside bevel, since that is all that shown thru.

70 is more relevant to shooting people's faces topside, because if I remember rightly 70 is about the right level for human skin. 100 is more relevant to underwater use. But don't be too rigid about having every single part of the frame under 100 because if you have small harsh highlights that you can't avoid, and you bring these under 100, then the picture in general might get too dark. But you should avoid significant areas of the picture being over 100.

Yup the best exposure is usually stop down 1/3 stop after no 100% zebra showing. This is for daylight outdoor but works for shots with lights as well. Of course, judge how the light is on the subject... that's what counts.

I've attached readouts for it from my scopes in Sony Vegas. The first one shows the waveform displaying only "luminance". Things look worse in the 2nd pic when it's displaying "composite" and it goes upto about 114% but I don't understand exactly what the "composite" mode means. Apparently it combines the luminance and colour levels, but what exactly does that mean and what should the limit be? Anyone?

Luma and chroma combined = composite.

Broadcast standard is usually 95-115 (depends on the broadcaster). Keeping it under 100 is always a good thing (unless you want the bleached look).

When I put a "broadcast colors" filter on that clip, it only brings the composite level below 100% if it's in "extremely conservative" mode. In "lenient" mode it just brings the luminance level down to 100% and leaves the composite level up over 110%.

Luma(Luminance) is the brightness of the picture. Broadcast color plug-ins can be crude butchers. Better to shoot a well exposed master and work on saturation and gamma in post.

To darken up the silver of the HC7 barrel that was showing up thru my SWP25, I used a Sharpie Rub-a-Dub Laundry Marker.

I did exactly the same thing on my Sony TRV40 which was reflecting slightly in my Stingray II housing.

Luma and chroma combined = composite.

Well that's what the manual said too. But surely the RGB parade in the lower pane is displaying a combination of luma and chroma Sorry to be thick, but what exactly does it mean in "Complete Idiot's Guide to Video Scopes" terms? Does FCP show composite? Do you use it?

Question for ya, just how important do you feel it is to have the white card you are w balancing off of to be in focus? I always make sure the card is in focus but am not sure whether this is really necessary.

Steve B)

But did anyone actually take the HC7 to 30m and lived to tell us about it ? We know the HC3 performed well underwater, does the HC7 ?

Hi Frenchguy

I've just got back from a 3week 50dive trip with a HC7 on which we did a fair amount of diving 30m and below. Like many have feared the HC7 likes LOTS of light. There were times while deep that I felt like I was diving with a Hi8 cam, however when it has lots of light or you get really up close it produced some absolutely stunning results.

Some of the macro stuff I shot with it was amazing when compared to SD results I've had in the past. Well lit WA also looks amazing. But if you're planning on going deep with it or dive in areas that have limited light filtering through from above then you need to know that it has some fairly serious limitations. It's not going to produce 5star results in those situations.

Hope this helps and if I can find the time I'll write something up in more detail with screenshots.

Cheers, Simon

Question for ya, just how important do you feel it is to have the white card you are w balancing off of to be in focus? I always make sure the card is in focus but am not sure whether this is really necessary.

Steve B)

I doubt that matters at all Steve, as long as it's taking up all or most of the frame. In fact it could almost be argued to be better out of focus.

Hi Frenchguy

 

I've just got back from a 3week 50dive trip with a HC7 on which we did a fair amount of diving 30m and below. Like many have feared the HC7 likes LOTS of light. There were times while deep that I felt like I was diving with a Hi8 cam, however when it has lots of light or you get really up close it produced some absolutely stunning results.

Simon, interested to know what exposure mode you were shooting in? Fully auto, aperature priority etc. Also, did you have auto-gain on or off? Where were you shooting, with what kind of viz/ambient light? Thanks!

Simon, interested to know what exposure mode you were shooting in? Fully auto, aperature priority etc. Also, did you have auto-gain on or off? Where were you shooting, with what kind of viz/ambient light? Thanks!

Unless I missed something in the manual and menus, the HC7 doesn't have any gain control. I think other than ensuring you shoot in adequate light, you stuck with manually turning down the exposure or AE shift in hopes that it will be reduce the gain...

Unless I missed something in the manual and menus, the HC7 doesn't have any gain control. I think other than ensuring you shoot in adequate light is to manually turn down the exposure or AE shift in hopes that it will be reduce the gain...

That's right, it was the auto slow shutter speed option I was thinking of. I have turned that off on my camera, but I don't think that will stop the camera from kicking up the gain.

Hi guys

Yes the auto slow shutter is unuseable - turn it off!

As for everything else then I tried pretty much every combination of manual controls - both touch screen and cam dial. I was diving in tropical conditions, but some dives were very early morning (low light) and vis wasn't always as good as I hoped it would be. If fact it varied from below 10m through to 40m. So in very brief summary...

Exposure - the auto settings actually performed pretty well. It was usefull though to be able to adjust exposure manually when you needed to.

AE Shift - Rarely used this as Exposure overides it - however it was a usefull tool at times.

WB Shift - Pretty much useless as it is only for 'fine tuning' wb. I could barely see a difference in any of the settings while underwater.

Focus - Auto and Manual worked very nicely for macro. Auto was pretty much unuseable for WA. I mainly relied infinity for most of the WA shots, but at times using this I would find that I had blobs of out of focus particles passing across the sceen. I bascially didn't really find a perfect setting for this.

MWB - Hmm well mixed results with this too really. Above 5m with plenty of light it would WB well without a filter. From 5 - 15m it would almost always WB off sand or the surface with a red filter. Below 15m really depended on a dive by dive basis. The lowest I managed to MWB off the surface was around 35m, but it was problematic from 15m down (not to say it was impossible and I normally got it in the end but buggering around trying to WB below 30m was often a stupid thing to do).

Of course one of the biggest drawbacks of the HC7 for uw is the lack of manual gain control, which is a shame.

I never imagined the HC7 would be a perfect camcorder. I knew it would have limitations and with these in mind it performed more or less as I hoped for. When they finally make the perfect cam that I'm waiting for I'll buy it - until then the HC7 will do

I really will try to write something up in more detail as soon as I can - this is really just a very brief summary, but I hope it helps.

Cheers, Simon