Blue cast on my neg.

Matt Wells · June 4, 2004

I was wondering if anyone can tell me the possible reason for a blue cast over my film.

It is only very slight (nothing like K40 in daylight with no correction), and actually looks pretty good.

The films most affected (all 16mm) are:

Fuji 250T all shot in daylight with correction

Fuji 400T all shot in daylight with correction

Now I am wondering if it could be one (or all) of the following:

- wrong correction filter. I just assumed the filter I was using was correct - came with the camera - it looked correct (embarrasing mistake I know )

- There was a very long gap between exposing the footage and processing (also embarrasing )

- the camera needs attention? (however the images are VERY sharp and ROCK steady)

Obviously this could be adjusted if I telecine the footage again, but it is not critical stuff so I probably wont bother.

I would just be interested if anyone can offer any ideas here.

One interesting point is that I also shot some Fuji Reala 500D, outside, obviously without correction, and this is slightly better - this obviously points to my correction, but I was wondering if anyone had any other ideas.

Matt

GeorgeSelinsky · June 4, 2004

Are these film dailies or tape? If it's tape, then the telecine operator could have simply screwed up. I think if you shot with correction the whole way and didn't have any confusing scenes, they should retransfer it. If it's film dailies it's also possible the timer screwed up, same would apply but they're usually less likely to reprint than to retransfer.

Is the daylight correction filter salmon colored? That is the correct color. If it is blue, then you prolly used an 80, not an 85, which is for correcting daylight stock in tungsten light (an underexposure would also be likely, since that filter eats about a stop and a half versus the 85).

- G.

June 4, 2004

I would suggest to check your mate-box, your filters holder. Is it possible that you got some lights from behind the filter and reflected the lens. If the you got reflection from behind the filter, this light will of course add bluish flair to the picture. With the daylight material it is less noticeable because there is no need for the correction filter.

good luck

R.E.L

Gareth Tucker · June 5, 2004

Two things spring to mind.

Firstly that "daylight" is not at a fixed colour temperature and is slightly bluer at certain times of day in certain places.

And secondly, I have been told that U.V light can register in the blue region of an image and in daylight there is a lot of U.V invisisble to the naked eye but visible to film. Although my first instinct is that any filter used on the camera will cut the majority out.

G.

Matt Wells · June 7, 2004

Thanks for the replys.

My filter is definitly an 85 filter, but I am not sure about wether it is a or b.

I have looked at the footage again (it is tape not print) and I think that I am going to speak to the telecine guy.

When I picked up the tape he mentioned to me that he thought it had a blue cast and let me view it there and then to show me what he meant. He also offered to put it through again, so mabey this was a hidden admission that he had got it slightly wrong.

The problem was that it was the first 16mm I had shot myself after super8, and I was so bowled over by the sharpness and reduced grain, I found myself just saying "wow that looks excellent, don't worry about the re-transfer"

As it is not critical I am not all that worried, but next time I will make sure I attend the transfer. I have some Super8 vision200T coming up and will definitely make myself present for that.

Saying this, the blue cast is only slight, and actually looks quite good, it is just that I had not intended it to be there when I first shot the footage.

Thanks,

Matt

Tony Brown · June 7, 2004

Posted this a couple of months ag0 - never did find the problem...

+++++++++++++++++++++++++++++++++++++++++++++++++

I've just completed shooting a commercial and have had a call from the colourist that always does our best lights. Everything has a strong blue cast, in some cases its off the scale and only just correctable.

We shot night scenes in Tokyo on 5279, locally processed, local Arricam & 435 and Cooke S4's

We shot day scenes in Dubai on 5248, unprocessed stock was carried hand luggage back to London and processed there. My own Arri 3 was used together with Local 535 & 435, Lenses all supplied from London. The neg was examined at two different Spirit suites, same results.

I don't get to see the neg until tomorrow, but the director has and says there seems to be a degree of overexposure throughout. I doubt this as my meter checks out against the spare that I carry and when shooting exterior on a beach with 100asa, it doesn't take a genius to know that its around 22 to 22 and a half as a general stop. If my meter had come up. with less than 16 then I'd have known ther was a problem. In any case I tend to under expose as a rule, not over.

So different countries, different stocks, cameras, lenses, spirit suits,labs......

I do not correct in camera which obviously pushes the blue way up - but in 10 years I've never had this before.

Phil Rhodes · June 7, 2004

Hi,

Oh yes. Film is so reliable. Experienced DPs know exactly whet they're going to get - they barely need a meter! It isn't a hugely long, complex chain of events with enormous opportunity for error at every stage. Oh no.

I'm not gloating over your misfortune, Tony, I'm really not, but this stuff seems terrifyingly common. All that Fuji stills stuff I did, exposed at what the camera asked for, came out a stop to a stop and a half under. Two of the four carts of super-8 I shot in LA and Vegas jammed. I am not seeing a fantastic track record here.

Phil

John Pytlak RIP · June 7, 2004

If the bluish cast is mostly in the shadow areas, I suspect age or radiation fog. How do the d-min (no exposure) densities of the affected film compare to other films of the same type?

Sam Wells · June 7, 2004

I would suspect matte box ' filter kick back issues only if all the footage shot at the same time & lighting, otherwise it would vary I'd think.

The "very long time" between exposure & processing -- depending on conditions - could certainly contribute to the problem, all the more reason to attend a retransfer, if it's purely a Telecine issue they can do it again and hopefully right, if it's fog level there may be options & you can warm it up etc.

85 vs 85B is insignificant.

-Sam

Matt Wells · June 8, 2004

Thanks again everyone - The time between my exposure and processing was a few months - and the telecine guy is very experienced, so this is now looking like the problem, especially as it seems to have affected the daylight balanced stock I shot too.

I am going to shoot some more soon, I will probably try some of the new Ektachrome 100D and project just to see how I am doing.

matt

Matt Wells · June 8, 2004

If the bluish cast is mostly in the shadow areas, I suspect age or radiation fog. How do the d-min (no exposure) densities of the affected film compare to other films of the same type?

Not sure about this technicality, but I do have all the technical leaflets from Fuji. is the d-min one of the graphs?

The blue cast seems to cover the whole frame, but it is more noticeable in the darker areas, such as the shadows.

Matt

John Pytlak RIP · June 8, 2004

Did you refrigerate the film in the "long time" between exposure and processing? If not, that could explain the problem.

The "D-min" is the density of UNEXPOSED film after processing. Any age or radiation fog will increase the D-Min, and reduce the contrast of the "toe" of the film that captures shadow detail. Many times, fog is NOT neutral, and will give a color cast, especially in the shadows.