Am I losing out using the ND filter at DVinfo.net

Mark Rook · July 31st, 2007, 01:23 PM

Are there any advantages/disadvantages in using the built-in ND filter.

Should I always use it when the camera recommends it.

Thanks,

Mark.

Steven Taylor · July 31st, 2007, 01:57 PM

Good question.. i've been wondering the same... if this is a post-chip effect surely there is no actual benefit that couldn't be gained in post? What is the difference between this and a negative gain? (I'm a newbie, humour me!)

Doug Davis · July 31st, 2007, 01:57 PM

http://www.digitaljuice.com/djtv/seg...how=all_videos

Good video and will probably help answer your question...

Steven Taylor · July 31st, 2007, 02:31 PM

ahah. Great answer :)

So I understand that concept using a physical ND filter... I have a more academic question though.. say you did record that very overexposed shot in the video, could you end up with the same DOF shot by applying an ND type filter in post? If the ND filter on the A1 is digital isn't it going to be giving a degradation in quality compared to a real physical filter affecting the actual light hitting the chip in the first place?

Eric Weiss · July 31st, 2007, 02:38 PM

the nd filter on the a1 is an actual glass nd filter.
learn how to shoot manual and apply the nd filters when you feel you should.
if auto-nd comes on, your shots can turn out very murky..like at a beach or something.
on auto, the camera has no idea what is sand, sun, water, etc.

Steven Taylor · July 31st, 2007, 02:59 PM

Quote:

Originally Posted by Eric Weiss

the nd filter on the a1 is an actual glass nd filter.

Oh really I didn't realise that at all. I'd presumed it was digital as I thought the switch would have felt more 'mechanical' (I've no idea why now...). Thanks.

Mark Rook · July 31st, 2007, 03:13 PM

Thanks guy's for all the reply's. I was just a little concerned that if I used it I may end up loosing some quality. So am I right in thinking that the filter will help use a wider aperture, and so may give a sharper image.

Thanks,

Mark.

Eric Weiss · July 31st, 2007, 03:23 PM

Yes. In ample light situations, using the ND's will provide very sharp shots with even exposure and a greater depth of focus.

You will not lose quality by adding ND's provided that your exposure is what you intend it to be.

Trust your VF over the LCD and don't rely 100% on the meter. I find over exposing my shots by a notch or two gives cleaner shots.

Stephen Eastwood · July 31st, 2007, 03:36 PM

Quote:

Originally Posted by Steven Taylor

ahah. Great answer :)

So I understand that concept using a physical ND filter... I have a more academic question though.. say you did record that very overexposed shot in the video, could you end up with the same DOF shot by applying an ND type filter in post? If the ND filter on the A1 is digital isn't it going to be giving a degradation in quality compared to a real physical filter affecting the actual light hitting the chip in the first place?

its glass in camera, you can never get the limited depth of field in post that you would shooting with it. I have it on good authority from the engineers that the internal ND on the canons is mated for the design of the chip and in their opinion better than using an external ND filter in its place. Of course an external may be needed as well if its not enough, I also use Circular Polarizers which cut light and glare.

Stephen Eastwood
http://www.StephenEastwood.com

Steven Taylor · July 31st, 2007, 03:42 PM

So if one was to use an external ND filter in combination with the internal filters what kind of rating would give a good set of choices?

Not that I have the problem of Hollywood sunshine here in the UK...

Stephen Eastwood · July 31st, 2007, 03:47 PM

If needed to shoot at a slower shutter or wider aperature than its ideal. Also a CP cuts about 1.5 to 2 stops of light if its ok to also cut reflections, sometimes thats intended so a CP would not be usable, but normally thats preferrable to eliminate them in shots of water or through glass.

Stephen Eastwood
http://www.StephenEastwood.com

Bill Pryor · July 31st, 2007, 03:50 PM

There are times in bright light when the camera's built-in ND filters aren't enough, and you end up shooting with the lens at the smallest aperture. By adding a screw-on ND, you can open up your aperture more. Most video camera lenses I've been involved with seem to like to be in the mid ranges of aperture, rather than stopped down or opened up all the way.

There is no quality loss with a good quality ND filter.

Steven, if a shot is too overexposed you won't be able to save it in post; though you might be able to get it within the realm of usability, but even then it will look crappy.

Eric Weiss · July 31st, 2007, 03:56 PM

i shoot a lot of beach, desert, and tropical content. i've never needed more than the 1/32. i also use a canon polarizer..which provides a bit more ND too.

i wouldn't suggest adding a lower quality ND to that lense. hdv is pretty unforgiving. If you must, buy a highly rated one...and here is some basic info.

Neutral Density filters have four main uses

• To enable slow shutter speeds to be used, especially with high speed films, to record movement in subjects such as waterfalls, clouds, or cars

• To decrease depth of field by allowing wider apertures to be used, which helps separate subjects from their background

• To decrease the effective ISO of high speed film (above ISO 400) and allow it to be used outdoors in bright situations

• To allow cine and video cameras (which have fixed shutter speeds) to film subjects such as snow, sand or other bright scenes which could cause overexposure

Neutral Density factors

• ND.3 (exposure adjustment = 1 stop, reduces ISO 1/2)

• ND.6 (exposure adjustment = 2 stops, reduces ISO 1/4)

• ND.9 (exposure adjustment = 3 stops, reduces ISO 1/8)

• ND 1.8 (exposure adjustment = approx. 6 stops, transmits 1% of light,)

• ND 3.0 (exposure adjustment = 10 stops, transmits 0.1% of light)

• ND 4.0 (exposure adjustment = 13-2/3 stops, transmits 0.01% of light)

• ND 6.0 = (exposure adjustment = approx. 20 stops)

Steven Taylor · July 31st, 2007, 05:35 PM

Quote:

Originally Posted by Eric Weiss

Trust your VF over the LCD and don't rely 100% on the meter. I find over exposing my shots by a notch or two gives cleaner shots.

Are you recommending the VF over the LCD because its not affected by direct sunlight? I've only done about 10 hours shooting with the camera so far but I must admit I rarely find myself using the VF.

Eric Weiss · July 31st, 2007, 05:44 PM

the lcd is fine to monitor and focus, but i find the vf to be more accurate with color temp and exposure. the lcd out of the box for me was brighter than the actual exposure..so my initial shots were too dark. also depending on the tilt of the lcd when you are looking at it, it will be brighter or darker
by design. my vf is quite accurate and a huge improvement over other canon cams.

July 31st, 2007, 01:23 PM	#1
Mark Rook Regular Crew Join Date: May 2007 Location: Aberystwyth, Wales, UK Posts: 91	Am I losing out using the ND filter Are there any advantages/disadvantages in using the built-in ND filter. Should I always use it when the camera recommends it. Thanks, Mark.

July 31st, 2007, 01:57 PM	#3
Doug Davis Major Player Join Date: Dec 2006 Location: Birmingham Alabama Posts: 259	http://www.digitaljuice.com/djtv/seg...how=all_videos Good video and will probably help answer your question... __________________ "The only thing the camera sees is light..." http://www.GoWildOlive.com

July 31st, 2007, 01:57 PM	#2
Steven Taylor Regular Crew Join Date: Jul 2007 Location: London, UK Posts: 44	Good question.. i've been wondering the same... if this is a post-chip effect surely there is no actual benefit that couldn't be gained in post? What is the difference between this and a negative gain? (I'm a newbie, humour me!)

July 31st, 2007, 02:31 PM	#4
Steven Taylor Regular Crew Join Date: Jul 2007 Location: London, UK Posts: 44	ahah. Great answer :) So I understand that concept using a physical ND filter... I have a more academic question though.. say you did record that very overexposed shot in the video, could you end up with the same DOF shot by applying an ND type filter in post? If the ND filter on the A1 is digital isn't it going to be giving a degradation in quality compared to a real physical filter affecting the actual light hitting the chip in the first place?

July 31st, 2007, 02:38 PM	#5
Eric Weiss Major Player Join Date: Mar 2007 Location: Philly,PA Posts: 360	the nd filter on the a1 is an actual glass nd filter. learn how to shoot manual and apply the nd filters when you feel you should. if auto-nd comes on, your shots can turn out very murky..like at a beach or something. on auto, the camera has no idea what is sand, sun, water, etc.

July 31st, 2007, 03:13 PM	#7
Mark Rook Regular Crew Join Date: May 2007 Location: Aberystwyth, Wales, UK Posts: 91	Thanks guy's for all the reply's. I was just a little concerned that if I used it I may end up loosing some quality. So am I right in thinking that the filter will help use a wider aperture, and so may give a sharper image. Thanks, Mark.

July 31st, 2007, 03:23 PM	#8
Eric Weiss Major Player Join Date: Mar 2007 Location: Philly,PA Posts: 360	Yes. In ample light situations, using the ND's will provide very sharp shots with even exposure and a greater depth of focus. You will not lose quality by adding ND's provided that your exposure is what you intend it to be. Trust your VF over the LCD and don't rely 100% on the meter. I find over exposing my shots by a notch or two gives cleaner shots.

July 31st, 2007, 03:42 PM	#10
Steven Taylor Regular Crew Join Date: Jul 2007 Location: London, UK Posts: 44	So if one was to use an external ND filter in combination with the internal filters what kind of rating would give a good set of choices? Not that I have the problem of Hollywood sunshine here in the UK...

July 31st, 2007, 03:47 PM	#11
Stephen Eastwood Major Player Join Date: Jun 2007 Location: Great Neck, NY Posts: 291	If needed to shoot at a slower shutter or wider aperature than its ideal. Also a CP cuts about 1.5 to 2 stops of light if its ok to also cut reflections, sometimes thats intended so a CP would not be usable, but normally thats preferrable to eliminate them in shots of water or through glass. Stephen Eastwood http://www.StephenEastwood.com

July 31st, 2007, 03:50 PM	#12
Bill Pryor Contributor Join Date: Jan 2003 Location: Kansas City, MO Posts: 4,449	There are times in bright light when the camera's built-in ND filters aren't enough, and you end up shooting with the lens at the smallest aperture. By adding a screw-on ND, you can open up your aperture more. Most video camera lenses I've been involved with seem to like to be in the mid ranges of aperture, rather than stopped down or opened up all the way. There is no quality loss with a good quality ND filter. Steven, if a shot is too overexposed you won't be able to save it in post; though you might be able to get it within the realm of usability, but even then it will look crappy.

July 31st, 2007, 03:56 PM	#13
Eric Weiss Major Player Join Date: Mar 2007 Location: Philly,PA Posts: 360	i shoot a lot of beach, desert, and tropical content. i've never needed more than the 1/32. i also use a canon polarizer..which provides a bit more ND too. i wouldn't suggest adding a lower quality ND to that lense. hdv is pretty unforgiving. If you must, buy a highly rated one...and here is some basic info. Neutral Density filters have four main uses • To enable slow shutter speeds to be used, especially with high speed films, to record movement in subjects such as waterfalls, clouds, or cars • To decrease depth of field by allowing wider apertures to be used, which helps separate subjects from their background • To decrease the effective ISO of high speed film (above ISO 400) and allow it to be used outdoors in bright situations • To allow cine and video cameras (which have fixed shutter speeds) to film subjects such as snow, sand or other bright scenes which could cause overexposure Neutral Density factors • ND.3 (exposure adjustment = 1 stop, reduces ISO 1/2) • ND.6 (exposure adjustment = 2 stops, reduces ISO 1/4) • ND.9 (exposure adjustment = 3 stops, reduces ISO 1/8) • ND 1.8 (exposure adjustment = approx. 6 stops, transmits 1% of light,) • ND 3.0 (exposure adjustment = 10 stops, transmits 0.1% of light) • ND 4.0 (exposure adjustment = 13-2/3 stops, transmits 0.01% of light) • ND 6.0 = (exposure adjustment = approx. 20 stops)

July 31st, 2007, 05:44 PM	#15
Eric Weiss Major Player Join Date: Mar 2007 Location: Philly,PA Posts: 360	the lcd is fine to monitor and focus, but i find the vf to be more accurate with color temp and exposure. the lcd out of the box for me was brighter than the actual exposure..so my initial shots were too dark. also depending on the tilt of the lcd when you are looking at it, it will be brighter or darker by design. my vf is quite accurate and a huge improvement over other canon cams.