Problem with ND filter/Colin might know..

[bnnrcn]

I have just uploaded two photos taken with a 10 stop ND filter in this thread Long exposures . My problem is the colour cast which was caused by my B+W 10 stop ND filter. B+W is known as a good brand and it is not cheap at all! I know that there are Singh-Ray filters which are known as best quality. So , I wonder it there is also such a problem with Singh-Ray ND filters? If they don't cause such a problem , I might buy a variable Singh-Ray ND filter in the future. BTW , I think I have started this thread in the wrong section,sorry about it

[dubaiphil]

You're going to get a colour cast with strong ND filter's, whatever the brand. Quoted as saying that Singh-Ray are best quality is going to ruffle a few B+W fanboys feathers, and allow S-R fanboy(s) to strut their stuff.

How about taking a WB reading from your original file before screwing on the filter and applying that to the 10 stopped image? That's worked for me in the past. If nothing else, it gets you in the right ballpark.

p.s. why do you see so many black and white very long exposure images?

[Manfred M]

Binnur - a +1 to Phil's comment

I've also posted a comment along with the images in question that you put up.

You are really dealing with two separate issues; the first is the colour cast that the filter introduces, and that is super easy to change in ACR / PS;

The second is that you are shooting mixed light; the reds, yellows and oranges from the setting sun versus the blue reflected from the sky. So any colour temperature you pick that pleases you is fine as the image has light where the colour temperature ranges from around 1800K to over 18000K. This is really up to you and you have to decide which way you want to bias the image. I've done work where I have adjusted the colour temperature in different parts of the image differently using layer masks.

When I look at your images; the first one looks like it has an "as shot" colour temperature adjustment and the second one has the look of the "auto" adjustment. Both look fine to me, and I personally prefer the second one; not because of the colour temperatures, but rather because we can see more cloud details in the sky.

[Mike Buckley]

p.s. why do you see so many black and white very long exposure images?

Ahhhhhhhhhhh. I had never thought of that.

[John 2]

If you are really bothered Binnur, you can buy an opaque lens cap (has a neutral white centre) quite cheaply. You fit this over your 10stop and then set the camera to take an auto white balance reading which you then store as a custom set up. You then set the camera to this every time you use your 10stop. I have done this and it works BUT frankly Manfreds advice is sound. It is just as easy to compensate in ACR/PS by de saturating the offending colour cast.

[bnnrcn]

Thank you Phil, I feel relieved because I'm planning to buy a Canon 70D in a couple of months and that's why I can't afford to buy a new ND filter right now

May I ask what you mean by reading WB from the original file ? I have a Canon 1100D and I'm afraid it is not possible to read the temparature and tint with my camera. I only have adjustments like auto,daylight,cloudy...but I don't have the values for temparature and tint

You're going to get a colour cast with strong ND filter's, whatever the brand. Quoted as saying that Singh-Ray are best quality is going to ruffle a few B+W fanboys feathers, and allow S-R fanboy(s) to strut their stuff.

How about taking a WB reading from your original file before screwing on the filter and applying that to the 10 stopped image? That's worked for me in the past. If nothing else, it gets you in the right ballpark.

p.s. why do you see so many black and white very long exposure images?

[bnnrcn]

Thank you Manfred If this is the case , I will try to do my best with ACR. I uploaded the first image with 'as shot' color temparature in order to show how the filter creates a colour cast and I cooled the colours by changing temparature and tint in the second one.

Binnur - a +1 to Phil's comment

I've also posted a comment along with the images in question that you put up.

You are really dealing with two separate issues; the first is the colour cast that the filter introduces, and that is super easy to change in ACR / PS;

The second is that you are shooting mixed light; the reds, yellows and oranges from the setting sun versus the blue reflected from the sky. So any colour temperature you pick that pleases you is fine as the image has light where the colour temperature ranges from around 1800K to over 18000K. This is really up to you and you have to decide which way you want to bias the image. I've done work where I have adjusted the colour temperature in different parts of the image differently using layer masks.

When I look at your images; the first one looks like it has an "as shot" colour temperature adjustment and the second one has the look of the "auto" adjustment. Both look fine to me, and I personally prefer the second one; not because of the colour temperatures, but rather because we can see more cloud details in the sky.

[Mike Buckley]

May I ask what you mean by reading WB from the original file ? I have a Canon 1100D

I'm confident that Phil is referring to applying a custom white balance setting. Refer to "Custom White Balance" explained beginning on the bottom of page 115 of your camera manual.

[bnnrcn]

Thank you John , I think it is better to go for Manfred's advice I was worried if my B+W ND filter caused the problem but it seems that it is the general result of all strong ND filters.

If you are really bothered Binnur, you can buy an opaque lens cap (has a neutral white centre) quite cheaply. You fit this over your 10stop and then set the camera to take an auto white balance reading which you then store as a custom set up. You then set the camera to this every time you use your 10stop. I have done this and it works BUT frankly Manfreds advice is sound. It is just as easy to compensate in ACR/PS by de saturating the offending colour cast.

[bnnrcn]

Ahhhhhhhhhhh. I had never thought of that.

[John 2]

I think that's the right decision. The only problem might be if the colour cast is otter than a simple colour. By that I mean that if it is pure red, blue, yellow, green, magenta or cyan then the cast is relatively easy to eliminate. If it is a mixture of some of these, you will have to work at it a bit.

[bnnrcn]

Thank you Mike ! I have just tried what you suggested and I find it useful. I will try it next time when shooting long exposures BTW do you have a Canon 1100D too ? How did you know the page number in the user manual ?

I'm confident that Phil is referring to applying a custom white balance setting. Refer to "Custom White Balance" explained beginning on the bottom of page 115 of your camera manual.

[Manfred M]

Binnur - I suspect what Phil is saying is that you either shoot a white target (in the lighting conditions that you are shooting under), without the ND in place or shoot Auto White Balance and then when you open that shoot in ACR, use the colour temperature reading given there and apply it to the shot with the ND. If you use the white target, use the eyedropper tool in ACR to set the white point, and then use the colour temperature shown under the custom white balance.

[Mike Buckley]

Binnur,

I use only Nikon cameras, but please don't hold that against me, as I regularly commit far worse sins you should be concerned about.

I simply Googled Canon 1100D manual, loaded the PDF of the manual, used Ctrl+F to conduct a search of white balance within the PDF, saw that the Table of Contents explains white balance beginning on page 115 and read the explanation.

[bnnrcn]

Thank you Manfred.I think it is possible to do what you have suggested during the shooting session by following Mike's idea. I tried 'Custom WB' function in my camera a few minutes ago. First I shot a photo with auto WB as you said above, then I recorded it with custom WB function. Then if I want to use those settings for the next photo, I just have to choose custom WB option in my WB settings. Very useful function

Binnur - I suspect what Phil is saying is that you either shoot a white target (in the lighting conditions that you are shooting under), without the ND in place or shoot Auto White Balance and then when you open that shoot in ACR, use the colour temperature reading given there and apply it to the shot with the ND. If you use the white target, use the eyedropper tool in ACR to set the white point, and then use the colour temperature shown under the custom white balance.

[DanK]

I suspect what Phil is saying is that you either shoot a white target (in the lighting conditions that you are shooting under), without the ND in place or shoot Auto White Balance and then when you open that shoot in ACR, use the colour temperature reading given there and apply it to the shot with the ND.

I'm new to this. Up to now, I have never used more than a 3-stop ND filter, and while I bought a 10 stop recently (Hoya rather than B+W because users report less color cast), I haven't yet had a chance to use it. However, it seems to me that I would take a shot of a neutral target with the ND filter ON, rather than with it off. That would give the neutral target the color cast that you want to correct. Assuming it is not a complex color cast (John's point above), it would then be trivial in LR or ACR to correct the color cast in that shot and copy the results to the image you care about. Am I missing something?

[bnnrcn]

Thank you Dan I can't really make a judgement on your comment because I'm new into long exposures too. But, all I can say is that, your suggestion would be time consuming at sunset time. Because, as you know, there is very short time for sunset shots especially with a 10 stop ND. So, if I shot a neutral target for WB adjustment with an ND and then shot my real scene I would loose half of my precious time. I think it is better to try the 'custom WB' function in my camera without screwing the ND filter and apply it to the image which will be taken with ND. If it doesn't work , I might as well correct the WB with PP.

I'm new to this. Up to now, I have never used more than a 3-stop ND filter, and while I bought a 10 stop recently (Hoya rather than B+W because users report less color cast), I haven't yet had a chance to use it. However, it seems to me that I would take a shot of a neutral target with the ND filter ON, rather than with it off. That would give the neutral target the color cast that you want to correct. Assuming it is not a complex color cast (John's point above), it would then be trivial in LR or ACR to correct the color cast in that shot and copy the results to the image you care about. Am I missing something?

[Manfred M]

I'm new to this. Up to now, I have never used more than a 3-stop ND filter, and while I bought a 10 stop recently (Hoya rather than B+W because users report less color cast), I haven't yet had a chance to use it. However, it seems to me that I would take a shot of a neutral target with the ND filter ON, rather than with it off. That would give the neutral target the color cast that you want to correct. Assuming it is not a complex color cast (John's point above), it would then be trivial in LR or ACR to correct the color cast in that shot and copy the results to the image you care about. Am I missing something?

Dan - You are right on. The issue with Binnur's shots is that they are classic mixed light at sunset ones, so personal preference are probably more of a driver than anything else.

I always tweak what comes out of the camera; I have a 5-stop Tiffen and a 10-stop B+W and frankly have not been bothered by any colour cast from either, probably because I always work the image WB, even when shooting without a filter.

[dubaiphil]

I'm shooting RAW, so I can adjust WB in post. Lazy, I know.

I'm simple you see - I build my long exposure shots from an image with no filter

Naked lens - make a mental note of settings
Add Grad ND - make a mental note of settings if different (maybe metering off the brightest area and doing a mental check that I'm getting roughly the amount of stops that my filter's supposed to give me)
Add 10 stop - add 10 stops to shutter speed and shoot - if there's changing light levels during sunset/sunrise then an adjustment of the shutter speed based on gut feel to suit

Now if I'm in RAW and auto WB, then I can see the adjustments to WB in post processing and I have my original Auto WB setting which generally gets things right - then I can apply the same WB to the image with the Grad ND and 10 stop

[Mike Buckley]

Thank you Mike ! I have just tried what you suggested and I find it useful. I will try it next time when shooting long exposures

The thought just now occurred to me that making a custom white balance setting is also very helpful in other situations, most often when for whatever reason your camera's auto white balance capability or your camera's white balance presets aren't as good as what you prefer. (It's likely that your upcoming 70D has a better auto white balance than your 1100D, at least based on my experience of upgrading to a later-generation Nikon camera.)

You can also use the custom white balance when there is more than one light source perhaps even more obvious than the one Manfred explained; you can set the white balance only for one area of the scene but that can be the most important area, leaving only the less important areas for you to adjust during post-processing.