Help needed on Hitech Filters

[JacePhoto]

Hi everyone,

I am using Hitech Filters and have difficulty understanding them. I like to find out if it is human error or product error.

#1 Hitech ND 10 (Big Stopper) and 0.9 Soft grad combined - 7 pm

> I have a strong blue color cast in this picture that i cannot seem to correct in Photoshop no matter how hard i tried.

[/url] Help needed: Weird Color cast in Evening shots? by 1000words.com.sg, on Flickr[/IMG]

#2 But i have no problems when there is strong sunlight. (Picture taken in the morning)

[/url] Filters Stacking help needed by 1000words.com.sg, on Flickr[/IMG]

Appreciate your help

 

[nitewalk]

Correct me if I'm wrong, the blue cast caused by Hitech ND filters is because the filter itself is relatively less able to cut out blue wavelength in the visible light spectrum. On a cooler/cloudy pre-dusk, the temperature is cooler hence the intensity of the blue wave will be greater and since it is less able to cut out blue wave compared to others in the spectrum, you would get a stronger blue cast than earlier in the day when the temperature is higher.

 

[JacePhoto]

Correct me if I'm wrong, the blue cast caused by Hitech ND filters is because the filter itself is relatively less able to cut out blue wavelength in the visible light spectrum. On a cooler/cloudy pre-dusk, the temperature is cooler hence the intensity of the blue wave will be greater and since it is less able to cut out blue wave compared to others in the spectrum, you would get a stronger blue cast than earlier in the day when the temperature is higher.

Okok. Thanks. As i am new to filters, is there any way to PP the blue cast in PS? I cant seem to find any answers in the forums (here or otherwise).

Thanks in advance.

 

[nitewalk]

Lol i tried. Tried desat the blue/cyan before doing auto-levels. The image didnt look decent. Plus it introduces vignetting. Did u try shooting without stacking? The additional 3-stop gnd could be too strong in reducing the intensity of other wavelengths in the visible light spectrum.

 

[tecnica]

Was the photo shot in raw?

I am using hitech gnd, though slightly cool but still not until to this extent.

 

[JacePhoto]

Lol i tried. Tried desat the blue/cyan before doing auto-levels. The image didnt look decent. Plus it introduces vignetting. Did u try shooting without stacking? The additional 3-stop gnd could be too strong in reducing the intensity of other wavelengths in the visible light spectrum.

I have been real clumsy and careless. I think i did so but didn't label. I guess i need to rework this.

Just a curious question, has anyone stacked (Hitech) ND 10 and CPL filters together to get reasonable colors?

Many thanks.

 

[JacePhoto]

Was the photo shot in raw?

I am using hitech gnd, though slightly cool but still not until to this extent.

Hi Technica,

Yes, i shot both images in Raw and Jpeg. Posting the Jpegs.

For the RAW, i still couldnt recover the images. haha.

 

[edutilos-]

Have you tried doing custom WB, 10,000K and adjust blue --> amber?

Otherwise, try select white point for WB and click on the part that should be a cloud (i.e. white).

 

[catchlights]

the only explanation is there was't much warm tone wavelength present during dusk hour, and the filters were too strong, filter out all the warm tone wavelength and there is noting left, so you won't able to correct it at the post.

 

[Eng Hoe]

I have been real clumsy and careless. I think i did so but didn't label. I guess i need to rework this.

Just a curious question, has anyone stacked (Hitech) ND 10 and CPL filters together to get reasonable colors?

Many thanks.

I think 10 stop filter will usually give you color cast. No diff even with expensive brands like Lee, except that for Lee filter, the color cast is easier to correct. Things get worst if you stack filters.

Next time, try to shoot with custom WB or convert to BW.

 

[JacePhoto]

Hi everyone, thanks for the inputs. i have changed to 10,000k as adviced by Edutilos. The results were almost like the day i shot it except much desaturated. I guess the human eye sees much more than the sensor. Noted on the wavelength and custom WB.

great to be learning from you guys.

[/url] Changed to 10,000k as adviced by Edutilos by 1000words.com.sg, on Flickr[/IMG]

 

[Francis247]

If you shoot in RAW, try changing the WB Shady and also tune up to around 9200k. That should be quite reasonable. It suffered the same blue cast like the LEE Big Stopper.

 

[HighTone]

I also have this problem and not knowing what to do, a friend told me to set WB to warm. have yet to try it. Thanks to TS for posting it and Edutilos for the hint about setting CWB 10,000k.

 

[nitewalk]

I also have this problem and not knowing what to do, a friend told me to set WB to warm. have yet to try it. Thanks to TS for posting it and Edutilos for the hint about setting CWB 10,000k.

You could see it as compensating the cooler colours by using a warmer tone in custom WB

 

[Squid]

I have similar experience and worked around it by either increasing the colour temperature of white balance and/or increase the exposure time. At times, the reciprocity rule fails me and I have to extend the exposure time by one or two more stops. For example, instead of calculating for exposure time for ten stops, I increase exposure time to eleven or twelve stops (depending on what the histogram tells me) even though the filter is a ten stops filters.

 

[Mythmaker]

Whenever I use the big stopper, I have to set WB to 11500K or 12500K (magic lantern). Otherwise at 10000K it's still giving a strong blue cast lol.