Camera Labs

Guys I have searched "ND Filters " but I did not find my answer. I recently bought a Hoya ND 4 and ND8 of a web site. They cost £20 each which I thought was good.
After using them I am very unhappy with the results. I get colour casting and the pictures are not good.
I want to buy good ND filters and wanted some recommendations please. I want to use them mainly for slowing down water eg The beach of waterfalls etc.
I now have a Nikon D90 and a 18mm-200mm VR lens.

Paul

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Nikon D7000. Nikon AF-S DX 18-200mm f/3.5-5.6 G ED VR II Lens, Nikon 50mm 1.8D, Tamron 10mm-24mm

This is one of the pictures I took.


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Nikon D7000. Nikon AF-S DX 18-200mm f/3.5-5.6 G ED VR II Lens, Nikon 50mm 1.8D, Tamron 10mm-24mm

Unfortunately there are few bargains when looking at filters.

Hoya is a good brand, but their cheaper options are just that. It's the same mantra as with tripods - buy cheap and buy twice.

Now you've got two main options. The circular screw in filters and the square/rectangular drop in filters into a holder that screws into the filter thread of your lens.

I'd recommend the second option, but availability is nil at the moment (for me especially) for Cokin or Lee. Cokin are OK quality, but Lee is the best.

So that brings you back to the most user friendly starting option, the circular screw in filters.

Hoya are good if you go further up the price range, Singh Ray do an excellent Vario ND filter (2stops to 8 stops if I remember rightly), Heliopan are excellent, and B+W are probably the best quality for the price.

The next thing, to minimise your outlay, is to choose the correct filter thread size. If you have several lenses with different thread sizes, then buy a quality step up ring or two so that your expensive ND filter can fit all lenses in your bag.

And the final hint. If you've got a good filter, don't skimp on a cheap step up ring. They can get stuck or fuse!

and if you're looking as slowing down water, especially during daylight, you will get a slight colour cast.

I think your main issue with your lack of excitement over the results with your filters is that if you are stacking them and really pushing the camera and lens to get that slow shutter you're after, you are really degrading your image quality.

For example, what were the settings on the shot you posted?

If you want to really blur photos during the daytime, then you'll need more than a combined 2 and 3 stop filter. You're getting into the realms of a Lee Big Stopper, Hoya 9 stop or B+W 10 stop.

With any filter this string you will get a slight colour cast, but with experience you'll learn how to correct in photoshop.

Thanks for your reply

I was looking at picture you had taken last night and may I say that, first they are amazing and second thats what I am trying to do !! I was reading the explanation on how you obtained a longer shutter speed and I kind of understand it. This said I would struggle on site with it while trying to shoot at the same time

The picture I took was at 1/4 sec at F20, ISO 200 at 22mm. I always have a UV filter on and this was also on the camera along with the ND4 and ND8. Maybe I should just have one filter on?

Paul

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Nikon D7000. Nikon AF-S DX 18-200mm f/3.5-5.6 G ED VR II Lens, Nikon 50mm 1.8D, Tamron 10mm-24mm

Pushing the 18-200 to F20 isn't going to help your image quality. Also, keeping the UV filter on as well as two ND filters is adding 3 extra layers of glass in front of the camera, which isn't going to help.

Another thing - 1/4 second on a tripod? If so, was VR switched on or off, as if it was left on then this could effect things further?

And thanks for the comment - I'm not sure which shot you're referring to though.

Here's a link to a post a while back, explaining how I got to a really long shutter speed in the day to get some cloud movement in the shot - this may help:

http://www.cameralabs.com/forum/viewtopic.php?t=25382

It was really bright when I took the picture and the longest shutter speed was 1/4sec on a tripod. I used F20 so as to get all the wall in focus. Why would using F20 affect image quality? Also the VR was switched of.
Can you give a link to where I can buy good ND filters. I don`t want to buy from -bay

Paul

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Nikon D7000. Nikon AF-S DX 18-200mm f/3.5-5.6 G ED VR II Lens, Nikon 50mm 1.8D, Tamron 10mm-24mm

You'll get diffraction, which is a slow decline in image quality as you reduce the aperture.

I can't buy anything locally in Dubai, so I buy in from B&H or Adorama in the US. If you're using them, there's a cameralabs link which helps to support the site.

There must be some local UK alternatives, but their price to me including shipping is more expensive.

Few reasons of loss of quality:

18-200mm is not the sharpest lens already, that's a "problem" with superzooms (quantity over image quality)
3 filters stacked (incl UV filter)
Stopping down beyond F/11 aperture (diffraction)

As to using F/20 to have the wall in focus, there is a thing called hyperfocal distance, and it has something to do with wide angle lenses and aperture and focus distance. I cant explain but if you would like to know, read up on it.

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- Wout -
Nikon D80 with 18-70 DX, 70-300 VR, 35 1.8 DX
Manfrotto 055XPROB tripod with 488RC0 midi ballhead
Lowepro CompuRover AW and Nova 200 AW

Just one more note, unless ISO200 is your lowest setting, I suggest using ISO 100..

Nikon D90 has 200 as lowest calibrated ISO, so I would not recommend ISO 100 unless you are sure it gives the look you want it to be (ISO 100 is "Lo"-setting on the D90/D5000/D300s)

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- Wout -
Nikon D80 with 18-70 DX, 70-300 VR, 35 1.8 DX
Manfrotto 055XPROB tripod with 488RC0 midi ballhead
Lowepro CompuRover AW and Nova 200 AW

Why does the ISO setting stop at 100? Is `lo` not 100?

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Nikon D7000. Nikon AF-S DX 18-200mm f/3.5-5.6 G ED VR II Lens, Nikon 50mm 1.8D, Tamron 10mm-24mm

That is what I said, Lo is ISO 100 on your camera. But it used to be base ISO 100 on older models and the newer models do that again as well.

But be aware that Lo and Hi settings are equivalents to the ISO not 100% equal. The calibrated ISO (200-3200) should have the correct numbers compared to film.

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- Wout -
Nikon D80 with 18-70 DX, 70-300 VR, 35 1.8 DX
Manfrotto 055XPROB tripod with 488RC0 midi ballhead
Lowepro CompuRover AW and Nova 200 AW

Thanks for that

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Nikon D7000. Nikon AF-S DX 18-200mm f/3.5-5.6 G ED VR II Lens, Nikon 50mm 1.8D, Tamron 10mm-24mm