Neutral Density Color Shifts

[davetravis]

I recently did some E6 on Fuji Velvia and found that my waterfalls had a slightly magenta color cast that seemed to get worst as I went to a darker ND. I'm using the Hi-Tech brand in the Cokin P holder. Can anyone suggest a ND that doesn't have a color cast?
Thanks.

 

[Amund]

I have a Singh-Ray Galen Rowell series and have never experienced any color shift with it, seems dead neutral to me...

 

[Dave Parker]

I have never had color cast problems with the Hi-Tech stuff.....they have always been neutral, I have had trouble with color shifts in Velvia in the past if you were underexposing a small amount, the older ISO would go blue and the couple of rolls of Velvia 100F I shot did have some magenta in the whites, which flavor of velvia were you shooting? Also did you process yourself? or have them commercially processed? could be a variance in the chemistry as well.

Dave

 

[davetravis]

Dave,
I was shooting RVP50, and doing my own e6. Other rolls from the same batch, where I didn't use the ND's were fine. So I'm thinking it's the ND's. I also use the graduated ND's from Hi-Tech and have never had any color shifts...go figure. It's worst in the 3 and 4 stop puppies.

 

[David Henderson]

I've been using HiTech for maybe ten years now- anyway I'm on my third set of nd filters. I did get one batch from them , about five years ago I think, that had a distinct brown/purple look . They didn't get near a film; I discussed it with Formatt and they sent me replacements that were fine. The reason they gave at the time was difficulty in getting their usual dyes, and the need to source temporarily elsewhere, and they went into some detail about their measurement of neutrality and rejection of non-neutral filters.

But frankly I've seen enough on Photo.net to believe that the issue continues sporadically and that their noble statements about quality control of a few years ago were wishful thinking. Let me be clear though, a neutral HiTech is not unknown and is just as good as any other brand using CR39 - which means all the well-known ones. My own strategy is to continue to use them but to view them on white paintwork or a very white paper in daylight and on a Lightbox to assess any colour cast, and to be prepared to phone them up and send them back for replacements if I need to. Why bother? well I do have all their hardware, but it's mainly because they are so much cheaper than Lee or Singh Ray (not sold in UK) for something I need to replace every 2-3 years because they scratch. And frankly being UK based I can call them and sort out replacements in ten minutes and negligeable cost.

I have to say that I have seen at least one Lee Filter with an identical problem (may well use the same dye suppliers) and that I have a Hoya ND filter here(not a grad) that is a most unpleasant shade of green.

 

[JBrunner]

I recently did some E6 on Fuji Velvia and found that my waterfalls had a slightly magenta color cast that seemed to get worst as I went to a darker ND. I'm using the Hi-Tech brand in the Cokin P holder. Can anyone suggest a ND that doesn't have a color cast?
Thanks.

Could it be reciprocity color effect because of the longer exposure?

 

[davetravis]

FALSE ALARM!!!
Sorry guys! :confused:
I just went back through the slides and compared them.
I shot waterfalls on Maui using RVP50, and RVP100. The security people would not hand inspect my film and they x-rayed it going and coming back.
The 50 is fine, but the 100 has the color cast!
I used the 100 recently in Colorado and got the same results.
Into the trash can goes the 100.
Thanks for all the replies though.

 

[JBrunner]

Unless one of the machines was way out of whack two passes through carry on xray should not have had any discernable effect on 100 speed film.

 

[David Henderson]

I agree with JD Brunner. I've used lots of Velvia 100 after X Rays from hand baggage systems ( I don't often ask for hand checks) without having this problem. In fact i've never had a problem with hand-baggage X Ray with any film. I have used a fair bit of Velvia 100 though, and its certainly prone to bring out the slightest hint of red in a scene. The Velvia 50 , though arguably more saturated, doesn't overreact to red in the same way.

 

[Lopaka]

Dave, was that 100 or 100F? I found a slight magenta bias on some 100F I shot last year, so far none on 100.

Bob

 

[davetravis]

Dave, was that 100 or 100F? I found a slight magenta bias on some 100F I shot last year, so far none on 100.

Bob

Well it was Velvia 100, not the F, but only those rolls are tainted.
I've got my big fall trips coming up soon, so just in case I just ordered fresh film.
Thanks.

 

[Baxter Bradford]

.....Velvia 100 though, and its certainly prone to bring out the slightest hint of red in a scene. The Velvia 50 , though arguably more saturated, doesn't overreact to red in the same way.

This mirrors my experience entirely. The 100(nonF) distorts the red part of the spectrum in a non-linear manner; producing results which I find undesirable.

Thus I haven't used much of it! If you can get RVP50 for the Autumn colours, then I would suggest this route.

 

[roteague]

I recently did some E6 on Fuji Velvia and found that my waterfalls had a slightly magenta color cast that seemed to get worst as I went to a darker ND. I'm using the Hi-Tech brand in the Cokin P holder. Can anyone suggest a ND that doesn't have a color cast?
Thanks.

I've shot a lot of Velvia 100, and I've never run into this problem. Baxter has done a lot more extensive tests than I have though, I've only shot it under a few conditions; like ocean scenes, high mountain scenes. For my upcoming trip I'm shooting all Velvia 50, but I may sneak a couple of sheets of the 100 in to test how it works in desert scenes.