# HOYA ND8 - long exposure



## dfed (Jun 1, 2011)

Today I got myself a neutral filter "HOYA HMC Filter ND8". My idea is to use it for long exposure. My camera is Pentax K100, lens 18-55(kit). I took pictures at sunset, but the pictures are overexposed. I use ISO 200. I would like to take long exposure pictures as shown in the website of the filter producer HOYA FILTERS - The Difference is Clear

I even think that the pictures in the link above are made in daylight. What am I missing?


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## Jarrod268 (Jun 1, 2011)

Are you setting your shutter speed manually or in manual or shutter priority mode?



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## Big Mike (Jun 1, 2011)

A filter like that, can let you use a longer shutter speed that you would without it...but you still have to set your exposure correctly for the scene you are shooting.


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## Robin Usagani (Jun 1, 2011)

your metering is trough your lens.  So it doesnt matter if you have a filter.  I have a feeling you dont know how to meter without a filter either.


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## mjbine (Jun 1, 2011)

Get Understanding Exposure by Bryan Peterson  it will help with the basic understanding of exposure, metering and using filters.


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## dfed (Jun 1, 2011)

I use shutter priority mode.


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## Aye-non Oh-non Imus (Jun 1, 2011)

An ND8 is a three stop filter.  The photos in your link show a much slower shutter speed with the filter attached, probably around a three stop difference.


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## KmH (Jun 1, 2011)

Plus, for sunset photos you want a Graduated ND filter (GND)  so the brightness of sky is reduced, but not the foreground.

The example you linked to is not a sunset. Consequently, the entire scene brightness is reduced to allow a slower shutter speed to blur the waterfall.


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## Robin Usagani (Jun 1, 2011)

dfed said:


> I use shutter priority mode.


Bingo!

If you use shutter priority you still need to make sure the aperture number is not blinking.


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## Jarrod268 (Jun 1, 2011)

You need a VERY strong filter for daylight long exposures.... Like a 10 stop. Your 3 stop could help with water but you need to not force the shutter speed. Try aperture priority at f16 and let the shutter speed fall where it needs to.

If you need longere exposure use a smaller aperture like f22 (to experiment... Could cause diffraction)... Or stronger filtration.

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## JG_Coleman (Jun 1, 2011)

Jarrod268 said:


> ...you  need to not force the shutter speed. Try aperture priority at f16 and  let the shutter speed fall where it needs to.



Yeah, Jarrod268 is right on.  Your best bet is to use aperture-priority,  which will automatically choose a shutter speed that is in the right  ballpark.  

Even aperture-priority may leave your exposure a bit "off" with  particularly long shutter speeds though.  So, probably the easiest way  to ensure that you get the best exposure is to first take a shot in  aperture-priority mode and then review the histogram.  See if it is  under- or over-exposed.

From there, you have two choices.

1) You can pop the camera into manual mode and just add or subtract a second or two of exposure as needed.

or

2) You can stay in aperture-priority mode and use exposure compensation to adjust shutter speed.

Either way will work fine.  Manual mode will give you more direct and  precise control over the exposure, while using compensation in  aperture-priority will enable your camera to continue adjusting to  slight changes in lighting while still producing roughly the same  exposure that you dialed in after your test shot.



dfed said:


> I even think that the pictures in the link above are made in daylight. What am I missing?



The photograph wasn't necessarily taken in broad daylight, though it may very well have been.  However, even at dusk, you can _still _achieve very bright photographs if your shutter speed is long enough.  Honestly though, I wouldn't strive to "replicate" Hoya's sample photo... it is arguably over-exposed and exhibits "sun-burn" at the top of the waterfall where the highlights have completely blown out to pure white.  This is generally considered undesirable and tends to occur when shooting waterfalls in poor, inconducive lighting conditions.


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## dfed (Jun 2, 2011)

Thank you all for the advices.


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