Filter for IR contamination

Leonard Levy · June 17th, 2009, 04:05 PM

shinier fabrics seem to have more Red problem than others, but all fabrics are different.

Anthony McErlean · June 17th, 2009, 04:21 PM

Thanks again Brian,
I did a school concert a few lights ago, in fact I have to record it 3 times in total. The first night I didn't have my filter on, I thought, just wait and see what happens first, it wasn't long till I discovered I needed the filter.

I Think you said Brian not to leave it on at all times, only when needed.

Thanks.

Anthony McErlean · June 17th, 2009, 04:24 PM

Quote:

Originally Posted by Leonard Levy

shinier fabrics seem to have more Red problem than others, but all fabrics are different.

Did I read somewhere that reds can give bother too.

Brian Cassar · June 18th, 2009, 09:16 AM

Quote:

Originally Posted by Anthony McErlean

I Think you said Brian not to leave it on at all times, only when needed.

Yes that's what I did say a few weeks ago but I have changed my view. Due to the fact that the green vignette is hardly noticeable in wedding videography, I decided that if there is a possibility that I will run into this IR problem, I put on the filter immediately. I believe that people are more readily to notice a brownish suit (which should have been black) than a slight green vignette. Having said this, none have complained so far about the brown tint when I did not have the filter. But out of the 2 problems I prefer a black suit with a slight green vignette on wide shots only.

Leonard Levy · June 18th, 2009, 12:11 PM

Brian, Have you tried to color correct the green vignette out?

Brian Cassar · June 18th, 2009, 12:54 PM

Leonard, I didn't try hard enough. I use Premiere CS3 and I didn't find a quick way to do it and I did not bother to delve in further. If maybe someone can enlighten me......I'll appreciate it greatly!

I've realised that when one views the edited video on a 40 inch or larger TV, the eyes would focus in the middle of the screen and hence the green vignette at the edges is not so prominent. I do not know whether others would agree on this.

Jason Davenport · June 20th, 2009, 09:06 PM

Has anyone tried tricking the white balence with a 1/3 green gell in front of lens to balance the green out, or is it just too subtle.

Serena Steuart · June 20th, 2009, 11:07 PM

The tint isn't uniform, being a function of incident angle through the filter; increases from zero on axis to greater towards edges. Noticeable on wide angle. Can be corrected only in post, but since it is a function of lens focal length then correction isn't too painful.

Leonard Levy · June 22nd, 2009, 12:20 AM

Jason ,
The 1st prototype Tiffen Filter (still under development) is a uniform light green and balancing under that tint does work. As Serena explained the 486 is a green vignette green so it is not so simple.

Docea Marius · June 23rd, 2009, 06:08 AM

Today I received the filter 486, we tested the EX1 has a tenta vignetare green but the picture obtained is much more true to color. Is visible to outside shooting, but a ok:
Maybe to show something from tiffen, which is currently the best solution .. my opinion :-)

Les Nagy · June 23rd, 2009, 10:10 AM

Quote:

Originally Posted by Leonard Levy

Jason ,
The 1st prototype Tiffen Filter (still under development) is a uniform light green and balancing under that tint does work. As Serena explained the 486 is a green vignette green so it is not so simple.

If you have Tiffen's ear on this, they should consider making replacement filter sets for the EX3 ND filter wheel, or even a complete filter wheel assembly to replace the stock one. That would be the perfect solution. Replacing the stock filter wheel in the EX3 is a 10 minute job with a small screw driver. I believe it is even possible to replace the filters in the stock filter wheel with a bit of careful persuasion. One of these ideas would be the perfect solution and make using the EX3 an almost carefree thing. I have no idea how hard it would be to do this for the EX1.

Ed Kukla · June 23rd, 2009, 07:52 PM

Quote:

Originally Posted by Les Nagy

If you have Tiffen's ear on this, they should consider making replacement filter sets for the EX3 ND filter wheel, or even a complete filter wheel assembly to replace the stock one. That would be the perfect solution. Replacing the stock filter wheel in the EX3 is a 10 minute job with a small screw driver. I believe it is even possible to replace the filters in the stock filter wheel with a bit of careful persuasion. One of these ideas would be the perfect solution and make using the EX3 an almost carefree thing. I have no idea how hard it would be to do this for the EX1.

I'll second this idea. I really don't want to add a 4X4 or bigger filter on a matte box nor a 77 screw in if I don't have to. I also have the W/A lens so a filter for that will be even bigger and more $$$.

Leonard Levy · June 23rd, 2009, 10:35 PM

Tiffen is still working on development of the filter itself. Its probably premature to ask for them to create replacements for internal Sony parts and there may be legal issues - I don't know.
It would probably depend on whether they end up designing a filter that appears colorless. If it remains green then it would not work as an internal filter.

I think Sony may be working on this issue as well now.

BTW balancing through a green filter didn't work for me except through the Tiffen prototype.

Vincent Oliver · June 25th, 2009, 06:17 AM

I have just read through most of the posts on this thread.

Yesterday I shot a stage production of Grease using the EX3, with a Canon XH A1 as a second camera. The intention was to mix and match the two in post production. However, the IR contamination on the Sony has rendered the clips useless. The Canon clips are perfect. I am bitterly disappointed with the Sony footage and will have to go back for a re-shoot on Friday. This is the first re-shoot that I have done in my 38 years as a photographer.

For what it is worth, my opinion is that the Sony camera with the IR problem is not fit for purpose. I don't see why users should be looking to third party filters to correct a problem which should not be present. I am today writing to Sony to ask them to provide a solution, the camera as it stands is fundamentally flawed. I would urge other owners to also write to Sony.

Vincent Oliver · June 25th, 2009, 06:21 AM

Quote:

Originally Posted by Vincent Oliver

I think Art Adams gives a fair answer to the problem. For me it is not a real issue, as I said I just replaced my black jacket with another colour.

The creative person will always find a way arround any problem.

I take back what I said in my earlier post, it is now a real issue. This problem will be rectified when I go back and do my re-shoot using a Canon XH A1.

I am very, very angry

June 25th, 2009, 06:17 AM	#239
Vincent Oliver Trustee Join Date: Sep 2004 Location: Chislehurst, London Posts: 1,724	I have just read through most of the posts on this thread. Yesterday I shot a stage production of Grease using the EX3, with a Canon XH A1 as a second camera. The intention was to mix and match the two in post production. However, the IR contamination on the Sony has rendered the clips useless. The Canon clips are perfect. I am bitterly disappointed with the Sony footage and will have to go back for a re-shoot on Friday. This is the first re-shoot that I have done in my 38 years as a photographer. For what it is worth, my opinion is that the Sony camera with the IR problem is not fit for purpose. I don't see why users should be looking to third party filters to correct a problem which should not be present. I am today writing to Sony to ask them to provide a solution, the camera as it stands is fundamentally flawed. I would urge other owners to also write to Sony. __________________ Eyes are a deaf man’s ears. Ears are a blind man’s eyes Last edited by Vincent Oliver; June 25th, 2009 at 08:10 AM.

June 17th, 2009, 04:05 PM	#226
Leonard Levy Trustee Join Date: Feb 2006 Location: USA Posts: 1,684	shinier fabrics seem to have more Red problem than others, but all fabrics are different.

June 17th, 2009, 04:21 PM	#227
Anthony McErlean Trustee Join Date: Oct 2008 Location: Northern Ireland Posts: 1,081	Thanks again Brian, I did a school concert a few lights ago, in fact I have to record it 3 times in total. The first night I didn't have my filter on, I thought, just wait and see what happens first, it wasn't long till I discovered I needed the filter. I Think you said Brian not to leave it on at all times, only when needed. Thanks.

June 18th, 2009, 12:11 PM	#230
Leonard Levy Trustee Join Date: Feb 2006 Location: USA Posts: 1,684	Brian, Have you tried to color correct the green vignette out?

June 18th, 2009, 12:54 PM	#231
Brian Cassar Major Player Join Date: Jan 2007 Location: Malta Posts: 306	Leonard, I didn't try hard enough. I use Premiere CS3 and I didn't find a quick way to do it and I did not bother to delve in further. If maybe someone can enlighten me......I'll appreciate it greatly! I've realised that when one views the edited video on a 40 inch or larger TV, the eyes would focus in the middle of the screen and hence the green vignette at the edges is not so prominent. I do not know whether others would agree on this.

June 20th, 2009, 09:06 PM	#232
Jason Davenport Regular Crew Join Date: Sep 2008 Location: Dallas, TX Posts: 131	Has anyone tried tricking the white balence with a 1/3 green gell in front of lens to balance the green out, or is it just too subtle.

June 20th, 2009, 11:07 PM	#233
Serena Steuart Major Player Join Date: Jun 2006 Location: Studio Alnitak, Melbourne, Victoria, Australia Posts: 640 Images: 3	The tint isn't uniform, being a function of incident angle through the filter; increases from zero on axis to greater towards edges. Noticeable on wide angle. Can be corrected only in post, but since it is a function of lens focal length then correction isn't too painful.

June 22nd, 2009, 12:20 AM	#234
Leonard Levy Trustee Join Date: Feb 2006 Location: USA Posts: 1,684	Jason , The 1st prototype Tiffen Filter (still under development) is a uniform light green and balancing under that tint does work. As Serena explained the 486 is a green vignette green so it is not so simple.

June 23rd, 2009, 06:08 AM	#235
Docea Marius Regular Crew Join Date: Jan 2009 Location: Romania Posts: 175	Today I received the filter 486, we tested the EX1 has a tenta vignetare green but the picture obtained is much more true to color. Is visible to outside shooting, but a ok: Maybe to show something from tiffen, which is currently the best solution .. my opinion :-)

June 23rd, 2009, 10:35 PM	#238
Leonard Levy Trustee Join Date: Feb 2006 Location: USA Posts: 1,684	Tiffen is still working on development of the filter itself. Its probably premature to ask for them to create replacements for internal Sony parts and there may be legal issues - I don't know. It would probably depend on whether they end up designing a filter that appears colorless. If it remains green then it would not work as an internal filter. I think Sony may be working on this issue as well now. BTW balancing through a green filter didn't work for me except through the Tiffen prototype.