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-   Canon VIXIA Series AVCHD and HDV Camcorders (https://www.dvinfo.net/forum/canon-vixia-series-avchd-hdv-camcorders/)
-   -   HV20/Brevis + Snow, Ice, Sun :-) (https://www.dvinfo.net/forum/canon-vixia-series-avchd-hdv-camcorders/91473-hv20-brevis-snow-ice-sun.html)

Dennis Wood April 13th, 2007 10:39 PM

HV20/Brevis + Snow, Ice, Sun :-)
Here are some shots done with the HV20, Brevis35 (CF1), 50mm Minolta f1.4 lens (f2.8 to f5). I had an ND .9 and polarizer (4x4's in mattebox) out in front. Clips were captured using HDVsplit, and 2:3 pull down removal done in AE7.0. I found that unless the clips were captured seperately and each analyzed for pull down sequence individually, pull down removal would not work. HDVsplit (free) captures, splits and logs all clips from tape unattended. Other than adjusting brightness on two of the shots, there was no cc done.

The HV20 was in shutter priority mode, 1/48s shutter, with aperture locked at f 4.8

720p (24fps)...107MB wmv right-click/save

620x360, 48MB, mov right-click/save

Brad Vaughan April 14th, 2007 03:00 AM

Wow, fantastic!

What music is that?

Robert Ducon April 14th, 2007 03:56 AM

Oh my goodness. That was the sharpest outdoor stuff I have *ever* seen from a 35mm adapter. Exposure was spot on Dennis. You are the man! That's the best advert I've seen - the Brevis speaks for itself! ;)

EDIT: And on an (consumer) HV20 no less!

Peter J Alessandria April 14th, 2007 08:39 AM


Originally Posted by Dennis Wood (Post 659902)
The HV20 was in shutter priority mode, 1/48s shutter, with aperture locked at f 4.8

Great looking stuff Dennis (looks like the little girl was going for the camera on that one shot - my worst fear with three toddler-age nieces - LOL)

Two questions:
1. how are you "locking" the apeture on the HV20 in Tv mode?
2. how are you monitoring the video on location since I assume the Brevis results in a flipped image.

Dennis Wood April 14th, 2007 09:25 AM

Thanks guys :-) Music is edited from a track done by the Vulcan Dub Squad. My daughter has had a camera on her from pretty much day 1, so I just keep a lens-pen on hand for smudges and consider collisions a hazard of the workplace. I'll likely keep the HV20 around so she can start actually learning how to use it.

Peter, I just used the HV20 LCD for these shots. I do have a 7" Marshall HD but it's useless without a hood in strong sunlight. The HV20 LCD is bright enough so that if it's shaded from direct sunlight...it's actually pretty good. The image is indeed upside down (flip module almost done though) but like most adapter users, once you've done it a few times, your brain figures it out. I had a follow focus mounted so basically I would stop recording, frame the shot, hit focus assist to determine the focus points, then used the ff and focus marks on the lens as a reference to rack.

For aperture management I followed a workflow based on a few initial hours of testing with the camera. Playing the HV20 tapes back on the XHA1 you can view aperture, shutter and gain (although not ND filters deployed). After doing similar testing with a GS400 several years ago, the HV20 wasn't much different. You can zoom out completely and with the right angle of light observe the iris closing and ND filters sliding into place as you play with exposure. Here's what I've been doing for 24p adapter use:

1. Zoom out completely.
2. Set up zebras to display 70%
3. Set camera in 24p mode.
3. Place cam in TV mode (shutter priority) and set shutter to 1/48s
4. Frame a shot so about 30% of the frame is displaying zebras, then toggle exposure on using the joystick.
5. You should see +- 11db on the scale. 0 db corresponds to f4 to f5 when using this technique. f4 is usually a good estimate for the lens sweet spot.

Once the camera was set, I controlled overall exposure with only small tweaks on the HV20. The balance of light management was done with the two 4x4 filters, and the 50mm aperture. The Brevis/HV20 combination dictates that in these conditions, you need to lose something like 16.5 stops:

50mm at f5.6 = - 6 stops
ND.9 = - 3 stops
Polarizer = - 2 stops
HV20 at f4.8 = - 5.5 stops

Alberto Blades April 14th, 2007 10:23 AM

the letus footage from the other thread seems lot more sharper


the girl is sharp like a pic, but in this brevis footage theres always some softness

Rob Unck April 14th, 2007 10:27 AM


Originally Posted by Peter J Alessandria (Post 660085)
1. how are you "locking" the apeture on the HV20 in Tv mode?

I believe you have to keep Exposure toggled on as you shoot -- correct me if I'm wrong Dennis.

Brad Vaughan April 14th, 2007 10:49 AM

Thank you Dennis for taking the time to answer our questions.

David Garvin April 14th, 2007 12:30 PM


Originally Posted by Dennis Wood (Post 659902)
I had an ND .9 and polarizer

Did you rotate the polarier to darken the sky?

When I look at some of the shots (like at 23seconds) I thought you were using a grad on the sky because it's so dark on such an obviously sunny day.

I'm also curious about what's happening at 8seconds.

You pull focus to, and then go past "infinity" as the mountains miles away in the distance are brought into focus... and then go out of focus as you focus past them. Is this a byproduct of 35mm adapters due to backfocus issues or is it something else?

Dennis Wood April 14th, 2007 02:35 PM

You can see the relative effect of the polarizer as relative solar angle changes...so yes I did have one on there, and rotated to cut exposure as much as possible. The snow was so blinding and foreground so bright...it gave an interesting effect. Going past infinity on focus likely reflects a slight collimation error on my part. The test unit in question typically hosts about six different lens mounts for testing. We are currently integrating an updated front mount design that incorporates a micro-adjustable collimation feature...making adjustment in the field a snap...and obviously this unit does not have it :-)

Dennis Vogel April 14th, 2007 02:42 PM


Originally Posted by Alberto Blades (Post 660152)
the letus footage from the other thread seems lot more sharper

I don't know. Dennis Wood's footage looks pretty darn good to me. The smooth rack focus is great.

Good luck.


Rob Robinson April 14th, 2007 03:53 PM

It looks AMAZING!

I am anxiously awaiting my Brevis35 and can't wait to get the DOF that 35mm lenses offer without paying a small forture for a higher-end 2/3" CCD video camera!

Thanks Dennis for the footage - seeing is believing!

Rob Robinson

Peter J Alessandria April 15th, 2007 09:58 AM


Originally Posted by Rob Unck (Post 660156)
I believe you have to keep Exposure toggled on as you shoot -- correct me if I'm wrong Dennis.

I was just playing with the camera this morning (haven't had a chance to shoot much with it yet - I'm stil working on two DVX100 projects) but I discovered in Tv mode you can manually adjust (and thus "lock") the apeture! (I'm sure others already figured this out but I guess I'm a bit slow.) Yes, Rob, by using the joystick to select "EXP" you toggle between manual and auto exposure. Manual let's you adjust exposure in +/- 11 increments (probably equivalent of 1/3 stop increments?) Brilliant!

Full manual apeture and shutter (in increments at least) control, mic input, headphone output, 24p in HDV, decent autofocus - all for $900. Thank you Canon!

Dennis Wood April 15th, 2007 12:14 PM

Peter, that's correct...the procedure I outlined above for locking exposure and shutter in 24p mode describes the method to lock in aperture. Here's the catch. The exposure adjustment range depends on exposure conditions the camera is seeing when you toggle manual exposure on! There's gain to worry about (which you never see) and what looks like two ND filters that slide into play so unless you use some baseline for exposure before you lock it...you never know where 0 db is on the scale. That's why I set zebras at 70%, zoom out completely, and frame a scene with about 30% zebras showing. This method ensures that 0 db is somewhere in the f2 to f4 range.

If you zoom out completely while exposure lock is on, you can look through the HV20 lens and watch aperture change, as well as the ND filters slide in. You can't actually visualize the ND filters slide in, but you'll see reflected light from the aperture change colour. The behaviour of shutter speed/aperture/gain will vary depending on what shooting mode you're using. My tests all reflect shutter priority (TV) mode operation.

Scott Aubuchon April 15th, 2007 09:03 PM

Dude... that is SICK good color/sharpness. I have an HV20 and it doesn't look like that! Too bad it will set me back as much as the camera.

Will that work with my Canon 50mm 1.4?

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