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I'd say that a 200-300K difference should not be a show stopper, Sami. To my eye, your left grabs are too warm by some 1500K at least. Something else must have happened to your WB settings in this shooting...
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I have this problem bad. I shoot in the desert where the temperature of the desert floor can go to 150F. All my green shrubbery has gone brown and the sand colored desert a redish hue.
Does anyone know what I can do for this? Is there a IR filter for this extreme situation? |
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This is a very common problem though. The Redone is having the same problem, I've read of people having it with the DVX100 as well. |
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I just ordered one in size 77mm for about $200 and they said it was in stock. They have the slim-line that will work with the Sony sun shade and with the adapter for my matte box. I'll see if it works. The EX1 needs a protector there anyway and I can sell the 77mm B+W UV I have still new in the box. Anyone want it? |
Just found out an interesting piece of information, when the F23 was first released, some cameras experienced black reflective fabrics reading as magenta or sometimes blue. Sound familiar? Turns out, it was a bad batch of IR filters which were replaced, solving the problem. I'm thinking about Sony and trying to initiate the conversation...
-Sean |
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I contacted Sony today an officially registered a complaint. They said it was the first they had heard about it but would look into it and get back to me. I referred them to this thread and the fact that the same thing happened with the F23 when it was first released. Perhaps if we all do this they will at least compensate us for the filters we have to buy to make the camera work properly.
-Sean |
In Adam Wilt's test he saw this on both the F-23 and the Ex-1.
Can I put the 486 over my Ex-1 lens then add a 35mm adapter over it, or do I always want the 486 to be on the front? |
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Also, I believe Sean is right - we should all complain to Sony about the red problem; realy don't see a reason for $200 expenditure and hassle with additional filter just to get right colours from a CineAlta, "professional" camera... |
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Don Deignan |
that sounds different. This problem is really only visible on black subjects with certain dyes in them that reflect IR light. Sounds like a processing problem, although I don't think it's related to this. It does seem like it is a processing problem, and we should start a new thread about it so as not to hijack this one.
-Sean |
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Brian - or anyone else - does this filter fit under the EX1 hood? I would prefer it to the slimline version as I can attach things to the external thread if necessary. I know that the slimline version does fit. |
I ended up buying the B+W 489 instead of the 486 as the 486 did not work with 35mm adapters because it has to reflect the light back and it would be behind the adapter. The 489 absorbs it instead of reflecting it and it works great with the Mini35 for example.
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Michael,
Does the 489 fit under the hood, and does it have a thread on the outside? |
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there is so many glass in a mini35 adapter , i doubt a filter would still be necessary.
imagine that you add , the lens, the gg screen, the condenser, the macro lens. and you still need to go through the camera lens. |
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IR passes through many things that visible light does not. The 1 1/2 stops of light loss from the mini35 doesn't really matter, this problem is seen with the RED camera when using heavy ND's like 1.5 and 1.8 (5 and 6 stops!). I used to shoot infrared ektrachrome, and I'd use an opaque filter which blocked all visible light and only transmitted infrared. As far as the 486 behind or in front of the adapter, I'm thinking it doesn't matter. First off, the 486 doesn't reflect the IR light outward like a mirror, it dissipates it between the layers of the filter coating. Also, even if it did reflect the light, why should that matter? The camera won't see it anyway, the filter still blocks it even if it's not traveling straight in. The amount of IR and wavelength we're talking about isn't like a heat lamp, so you won't melt your lens. Later this week I'm going to try a 486 with a mini 35 and cooke S4's. I'll keep everyone informed.
-Sean |
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The 486 filter does work to solve the problem, but it really shouldn't have to be there. I ran into a situation today where I needed the filter, but also a wide angle adapter. Even if I could find a filter in the approriate size, the wide angle doesn't have threads, and I can't put it behind since it mounts to the bayonet. In this case I wouldn't be able to do the shot. I spoke to someone named Lou at Sony support again today, to express my displeasure in the camera not performing as it should. He said he had heard of this earlier in the week from someone who saw it only in certain lighting conditions. He sounded genuinely concerned about the problem and said he would have the engineering team investigate at the beginning of next week. I referred him to this thread, but I think if we all call and complain maybe we can force Sony to step up and fix this. I don't like having to put extra glass in front of the lens.
-Sean |
B&W 486 works fine, when you put it directly on the cameralens there is only a very very slight green coloring of the extreme corners when you zoom out all the way.
The Heliopan UV/IR cut filters give a greenish cast all over the frame and even more so in the corners when zoomed out. |
Peter, while the 486 does work fine and I haven't seen any green cast (unlike the 489) I still maintain that it shouldn't have to be there. This is a design problem. A lot of companies use a weaker IR filter to increase sensitivity, but just like they did with a batch of F23's, Sony used one that allows a couple of wavelengths to pass that shouldn't.
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Sean,
-I agree with you that a filter shouldn't be necessary at all, a proper one should be built in, maybe in the EX3. -B&W 486 looks very similar to the Leica UV/IR filters supplied for M8 camera, however they don't make a 77 mm one. -The B&W 486 is fine apart from very, very slight corner colouring when zoomed out, this is due to the light rays passing the filter at a very oblique angles in the corners. B&W says this happens at wide angles of 60 or more degrees and is inherent in the nature of this filter type. -When used with Letus Extreme there is no problem. -Light loss is minimal, in cool daylight only 1-2%, so I doubt light loss is the reason why the filter is not built in. -Only the Heliopan UV/IR filter gives a greenish cast and is therefore better avoided. |
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Yes Piotr, that is correct.
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Can someone who is at NAB ask SONY what if anything that they are going to do for us about the "RED" (infrared not the 3K Scarlet) problem?
Can the EX1 be retrofitted with a proper strength IR filter? Or is it up to us to take care of the problem ourselves with a screw-on filter? |
There are IR/UV combo filters available that would serve three purposes; UV filtering, IR filtering, and lens protection. It's much better to pre-filter the light to the sensors so that they can better sense only the needed spectrum. I hope that by insisting on this change that other more important things don't lose their priority.
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Mike, I think this is a more serious issue than you're giving it credit for. Pre-filtering the light to the sensors is what happens regardless of where in the optical path the filter is placed. I for one don't like to put any glass in front of the lens that I don't have to, since it defeats the purpose of the anti-flare coatings on the front element as well as taking up the filter slot under the stock lens shade. This is an image quality problem that can and should be solved, and sony doesn't have to stop working on the back focus problem to do that.
-Sean |
Guys,
I have just received my B+W 486 filter and put it on my EX1. I have shot some test stuff in daylight; no greenish cast in the corners at full wide, as some have reported. Also, while - without the filter - the picture (using absolutely neutral matrix settings) tends to have some bias toward reds (especially with Hisat matrix), it's completely natural now. But the real tests I will be doing this evening inside, with some tungsten lighting. I'll try to post some grabs of my girls' black and deep blue garment, which - without the filter - was notoriously recorded as brown or magenta, respectively. With the filter (which has been quite an expensive investment - with duty and VAT paid on top of the B&H price + shipment), I certainly do hope to be getting the right colours... Peter, my Letus kit being away at the moment - how do you fit LEX on the EX1, with the 486 filter in place of the Letus EX1 thread ring? |
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Just a quick update:
Yes, the black clothes look really black, and deep blue are not magenta anymore, with the 486 filter attached in tungsten light (2600-3200K). However, with all matrix settings being default (for both Hisat and Cinema matrices), red is not properly red anymore; will have to play with the settings and try to correct this. Also, in tungsten light the corners indeed get greenish tint at fully wide. All in all, the colours on my V1E looked much better, and without any filtering or the myriad of tweaks needed - this IR problem is something Sony should definitely be made to admit, and treat as a serious flaw on the EX1! Edit: You can see the clothes looking right with the 486, but the greenish tint also visible (at the furniture, in the corners of the right image). Of course, both pictures are not otherwise identical in their parameters as they were not taken the same day; the WB was not re-adjusted to compensate, etc. - but the tendency is obvious and I picked them on purpose, to show how the filter improves black and deep blue, but introduces other problems instead. |
Could someone post pics of the greenish cast. How bad is it?
This is disturbing to me. i was about to buy a 486 but am worried now. i talked t a Tiffen rep at NAB about this and he should me new IR filters that were quite expensive (hadn't come up with a price necc yet.) and were made with a very elaborate process. Lenny |
Lenny,
See my grabs in the previous message. |
Piotr, my 486 filter has threads on both sides, (I believe the slim version has only a thread on one side).
So I screw the filter on the cameralens and then the LEX onto the filter. |
Hi Piotr,
Those two grabs are very telling. I have just re-read Adam Wilts' very informative shoot-out (albeit rushed and 'unfair', by his own admission) between an EX1, RED One and F23 - as has already been mentioned he notices the very same IR-heavy color response exhibited by the EX1 (and to a lesser extent the F23) I hesitate to post grabs linked directly from his article but the effect appears so obviously that I think its noteworthy enough to justify this quote... "Aside from the progression in shallowness of depth of field, what’s striking is the difference in colorimetry. Both Sonys show Tim’s black shirt as a reddish-purple... " (from page 5 of his article which can be found here: http://www.provideocoalition.com/ind...s_ex1_f23_red/ ) Hopefully Sony are taking note and will act sooner rather than later. I would also suggest that you pester you're supplier for _atleast_ a reply from Sony on this issue. Thanks, Dave. |
I can now say definitively that the Tiffen Hot Mirror is not strong enough. I picked one up to hold me over until a 486 slim arrives, and it barely has any effect at all.
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Thanks Sean, That's very useful info.
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- does yours still fit under the EX1 lens hood? - when using it with Letus on, don't you see any contamination from the reflected IR bouncing between the filter and the achromat? |
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