Recently, I purchased a couple of 'new' second hand lenses. (see my earlier post, if you haven't already done so!)
I was happy to see that included in that deal were 2 variable ND filters. This was good because it meant that I didn't have to stack ND filters as I had been doing and also, I could focus through the variable filter at it's lightest setting and then adjust it to go darker without having to remove separate filters and then re-install them when I was ready to take the photo.
I went down to Rathmines where I knew there were some old piers of a wharf that had served the RAAF Base there when it was a Flying Boat Base. It was my intention to use the variable filter to get some long exposure shots using the variable ND filter.
The filter I was using is a ND2-400. ND2 being equivalent to 1 stop of exposure and ND400 being equivalent to 9 stops of exposure (according to Google!). The filter cuts out the light coming into the camera. This means that to get a properly exposed photo, the shutter speed slows right down and we are left with a long exposure photo. You can see some examples of long exposure here in a previous blog post.
I took a few photos, chimping as I went along. Now there's an interesting word; Chimping. It is a virtual new word and simply means 'immediately looking at the result of a photo on a digital camera after each shot'. Anyway, I wasn't entirely happy with the result. Considering that the top level of the variable ND is equivalent to 9 stops (allegedly!) I was only getting a 2 second shutter speed from ISO100 at f22; I had thought that I would get longer.
One thing about using the filter that I had not considered was the vignetting in each corner caused by using a filter on a wide angle lens. This happened all the time when opened up wide to 10mm.
Another problem also showed up and this is a common problem found when using a circular polariser on a wide angle lens; it makes one part of the photo go darker. Now, a variable ND filter is simply 2 pieces of polarising glass; one circular and the other linear. One filter is turned to offset the polarisation, making the filter darker or lighter. I did end up with this problem and a darker area appeared up the top of some photos, right in the middle!
I wasn't too impressed with my first use of a variable ND filter.
I think my next step is to purchase a 77mm filter holder and separate ND filters for this lens. It may be a little more fiddly but I think it would give better results. Once I have the holder to fit the lens, I can then purchase more filters for that as time goes on.
Photos Copyright ©Life with Jordy Photography
All Rights Reserved
|The RAW file. You can see the filter in the corners of the photo (at the widest of 10mm) and |
the dark blotch in the middle at the top caused by the polarisation on a wide angle lens.
Shutter speed at 2.5 second.
|It was always my intention to edit in B&W. Photo edited in Nik Collection, Silver EFEX Pro.|
Vignetting applied in Silver EFEX Pro helps to hide that dark blotch.