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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Hot Mirror/IRND/Mirror ND Filter Matrix [Parts 1-4]

Thanks Evin for the great review.

I've just ordered the Pancros. .6 .9 1.2 and 1.5

After ordering I just realized that the .6 is not combo and I don't think it has IR cut. Would the ND .6 without IR be an issue for the Red cam? I tried to look for also a combo .6 but I couldn't . Do you guys think it would be possible to just cancel the .6 filter on my ordered? My credit card has already been charged... :ohmy:

Thanks,

Ivan C
 
eyes wide open...

eyes wide open...

I was 100% sold on the panchros. Bought a set, shot a doc on them and I experienced nothing but trouble with "ghosting".

I was a huge proponent of these filters. Not anymore.

Even with just one of the panchros you risk ghosting if you have another filter (non-mirrored) behind it.

Even the "non-mirrored" side of the panchro seems extra reflective.

Almost impossible to eliminate a "double image" when dealing with specualar highlights.

Anyone want to buy a set of panchros .3,.6,.9,1.2?

Eyes wide open!

Dylan Macleod
Cinematographer
Toronto, Canada
www.dylanmacleod.com
 
I want to reiterate Dylan's comments. Here at NEVER2LATE Productions, we have both the Pancros and the Tiffens (IR+ND) for our two REDs and Nikon primes and zooms, and on a sunny day, outside, the Pancros are definitely trouble. Serious trouble.

We have really bad issues with ghosting, as well, and find that the Pancros are completely unusable when attempting to use a polarizer or another filter in the mattebox. In many conditions, we much prefer the Tiffens. This issue is NOT a problem with the mattebox (Redrock), as, in an attempt to eliminate the ghosts, we actually wrapped the entire front end of the camera in Duvateen. No effect. It strictly has to do with the direction of the sun's rays and strong reflections. We find that it makes little difference if there is more than one filter in the camera or not. We still have problems. It is possible that we are having issues with the clear filters on the front of each of our lenses, but who on earth uses their lenses on location without clear filters on the front?

In summary, if you aren't using a large external monitor when you're shooting, better be prepared for Casper to make his appearance in your footage when you download at home. Some of these effects are pretty subtle on a 5.5" RED monitor, but you can definitely see them when it's all blown up.

You can see exactly what I'm talking about in the last sequence (junk/car sequence) of the first eight minutes of our film on Vuze. Here is the link:

http://www.vuze.com/details/DCVVZAT...X&s=Sworks+in+progress&st=SRELEVANCE&t=X&vt=1

Watch especially for the highlights, and you'll see Casper in several places. Watch, as well, as "Patrick" walks from the front of the car to the door. It's subtle, but there it is, Patrick's ghost is about 3 feet in front of him. The most obvious one is the highlight that bleeds off to the right as the camera pans from left to right of the grill of the car.

Unfortunately, we will not be able to reshoot these images. We shot them before we had a large external monitor and, frankly, before I even knew to be looking for them. Fortunately, however, no one except me has ever really seen or mentioned them. (Even our superlative DP, Seth Iliff, didn't seem notice them on playback on the large screen.)

Stephen
 
I'm so new to this game, I would hesitate to make any real recommendations on a yea or nay for the Pancros, but, if I were doing it all over again, I would go strictly with the Tiffens.

Stephen
 
Stephen Pruitt said:
We have really bad issues with ghosting, as well, and find that the Pancros are completely unusable when attempting to use a polarizer or another filter in the mattebox. In many conditions, we much prefer the Tiffens. This issue is NOT a problem with the mattebox (Redrock), as, in an attempt to eliminate the ghosts, we actually wrapped the entire front end of the camera in Duvateen. No effect. It strictly has to do with the direction of the sun's rays and strong reflections.
Click to expand...

Stephen, I don't understand what you wrote, could you try it again?

Are you saying that Pancros in a Redrock mattebox are JUST FINE? Or that even in the mattebox wrapped with duvatine you have ghosting?
 
zak forrest said:
Stephen, I don't understand what you wrote, could you try it again?

Are you saying that Pancros in a Redrock mattebox are JUST FINE? Or that even in the mattebox wrapped with duvatine you have ghosting?
Click to expand...

I think he means that it is not because they hadn't properly sealed the mattebox...which is another way to get unwanted filter back reflection.

It should also be noted that some people have found ghosting in highlights with no filtration at all. This could possibly be when you get a prime lens with a large and flat back element. The reflective surface of the sensor can actually bounce an image back on to the back of the lens, and the lens in turn will send it back to the sensor... a ghosted image.

Dylan Macleod
Cinematographer
Toronto, Canada
www.dylanmacleod.com
 
Irnd

Irnd

Just a thought. Has anyone tried using the Vocas mattbox with the tilt frame on front? Would it help to put a tilt on the filters?

bob
 
zak forrest said:
What about a Tiffen Hot Mirror with some regular old ND filters behind it (closer to the lens)? Any problem with this? That's what the Hot Mirror is made for right? This thing with each Pancro IRND cutting more IR than the last is now confusing me, I was all set to get the Tiffen Hot Mirror while I wait for my Pancros to ship, but am a bit confused now..
Click to expand...

You could use either the Tiffen, Schneider or Rosco hot mirror in the front of the matte box and yes, then use any brand ND behind those. However I have found that you can only go up to about 1.2 with that method before you start to see a little IR effect compared to the Pancro.

That is why I have the .9 and 1.5 Pancro ND+IR filters for really bright light. I also have a plain .3 & .6 ND to adjust those 2 filters so I get the amount of ND I want. I have been shooting with the Rosco Tru-Color in the matte box most of the time I'm outside even if all I'm using is a Pola with it. Getting clean images so far but I just got the Pancro's so I'm not too happy to read about these problems. Damn I thought I was all set.
 
Dylan's interpretation of my original comment is the correct one.

I have had no luck putting ANY filters behind the Pancros using our Nikons, but no issues with ghosts using multiple filters using the Tiffens.

Stephen
 
Stephen Pruitt said:
Dylan's interpretation of my original comment is the correct one.

I have had no luck putting ANY filters behind the Pancros using our Nikons, but no issues with ghosts using multiple filters using the Tiffens.

Stephen
Click to expand...

Stephen, Dylan, did you also have ghosting with PL mounted lenses?
Thanks
Marc
 
Baab said:
Just a thought. Has anyone tried using the Vocas mattbox with the tilt frame on front? Would it help to put a tilt on the filters?

bob
Click to expand...

I am using the Vocas but didn't buy the optional tilt filter unit (it's like an extra $300 or something).

I have tried angling it by hand...it just seems like more hassle than it is worth, especially when there are other options that seem to be equally effective.

Dylan Macleod
Cinematographer
Toronto, Canada
www.dylanmacleod.com
 
Stephen Pruitt said:
but who on earth uses their lenses on location without clear filters on the front?
Click to expand...

In all the time I have worked in this industry I have never used a clear filter (B-glass) in front of the lens unless a stunt or SPFX reason warranted it.
 
Stephen Pruitt said:
We have really bad issues with ghosting, as well, and find that the Pancros are completely unusable when attempting to use a polarizer or another filter in the mattebox. In many conditions, we much prefer the Tiffens. This issue is NOT a problem with the mattebox (Redrock), as, in an attempt to eliminate the ghosts, we actually wrapped the entire front end of the camera in Duvateen. No effect. It strictly has to do with the direction of the sun's rays and strong reflections. We find that it makes little difference if there is more than one filter in the camera or not. We still have problems. It is possible that we are having issues with the clear filters on the front of each of our lenses, but who on earth uses their lenses on location without clear filters on the front?
Click to expand...

I use Master Primes without "clear" filters. This is to avoid problems you are describing.

A few questions:
1. Do you use mattes?
2. Do those mattes match the focal lengths of the lenses used?
3. What are the exact lenses and filters used?
4. Do they have highly reflective front element? Good lenses (such as Red 300mm or Master Prime) have highly transparent coating on the front element (see the picture of a master prime on my website http://www.achtel.com/equipment.htm )

I shot a fair bit of footage using Pancro 0.9, 1.5 and 2.0 (!) with True POL Schneider behind it. The conditions were: bright, sunny Australian day, which is about 1-2 stops brighter than what you would experience on your hemisphere. There were plenty of high contrast (white) objects on dark background. I shot with and against the sun at sunset. No reflections whatsoever.

Surely, you must be doing something wrong, you just need to work out what it is :unsure:
 
You could be right, Finner. It might just be the clear filters on the Nikons. I hesitate to remove them because that makes the probability of a ruination accident vastly higher. We don't have tons of money to run out and buy lots of new lenses. We are working in very, very dusty and windy conditions here in Kansas.

We will try the Pancros without the clear/UV filters installed and see what happens. However, if it is a choice between using the Pancros without the clear lens filters and the Tiffens with them, that's an easy decision for us to make. We'll go Tiffens every time.

Stephen
 
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  • #98
If you put ANY piece of glass in front of a Pancro you will see ghosting and reflections. If you put all your filters behind the Panchro you should be fine in all situations except specular light-sources. And even then it shouldn't be too bad unless it is a particularly focused beam right in the lens. Maybe tomorrow I'll try and do some testing.

Steven, most cine lenses, including my Zeiss primes do not get used with a protective filter. Unlike in still photography the chances of secondary reflections happening off your protective filters is much higher when shooting moving images. Your also more likely to have an AC watching out for the lenses on a more or less full time basis so the need for those filters is also diminished. Another reason for the severity of the reflections is probably the distance from the front protection filter to the Pancro, this gives a larger parallax error to the refection and makes the ghost appear farther away and more noticeable.
 
I want to be clear. We never put anything in front of the Pancros. The Pancros were always the first in line. We were NEVER able to use the Pancros with a polarizer behind them without significant ghost sightings, especially on the highlights, as mentioned. We'll try pulling the clear glass off, but I cannot imagine why it would make a difference to have clear glass on the lens, but other filters in the mattebox behind the Pancros.

Stephen
 
Stephen Pruitt said:
... but I cannot imagine why it would make a difference to have clear glass on the lens...
Click to expand...
because Pancro is a mirror, not an attenuator. If any of your filters reflects back, it will show as a ghost in the Pancro mirror. A typical clear glass filter can reflect ~5% of light back, and even the best once reflect about 1~2%. This light will reflect back from Pancro mirror and will show as a ghost. It is absolutely critical to use mattes and only high quality PL filter behind and only if necessary. Best not to use any other filter at all. Front lens element is curved, so it will not cause hard reflection, just tiny loss of contrast.

You haven't answered if you used mattes and what size they were.
 
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