But what is it exactly?
What you are looking at is a “stack” of four different camera lens filters attached to a AF-S Nikkor 18-70mm 1:3.5-4.5G ED lens. That I was attempting to use to get some long exposure shots of campus. But that isn’t important right now.
Since this is a new blog, let me give you the backstory as to why I was trying this ridiculous concept of stacking filters. My official job title is Technology Support Analyst. I’m housed within the Department of Geography and Earth Sciences but I report to the Office of Academic Technology (OAT). Recently I have been asked to help develop the CLAS image repository for use on college websites. Initially that meant taking panoramic pictures of CLAS buildings and computer labs but has since morphed into more “generic” photos of campus (generic meaning, non-panoramic in this case). So when I get some downtime from my technical support role, I very often wander campus with my camera and tripod looking for interesting things and places to shoot from.
Now, back to the bad idea. After a brief meeting this week I decided that I could take some long exposure panoramic pictures around campus in the middle of the day. Now if you are not familiar with the phrase “long exposure” and how it relates to photography I’ll explain. Typically when you take a photo with your camera, the shutter, which lets light pass through the lens into the digital sensor, stays open very briefly, usually in the range of one-two hundred and fiftieth of a second (1/250) but this number can vary greatly depending on the conditions. Now when someone speaks of taking a long exposure they are usually referring to the shutter on their camera staying open for one second or longer. Also when someone refers to a long exposure it’s a safe bet to assume they are taking a photo when there isn’t a lot of light available. So you can guess that attempting to shoot a long exposure photo in the middle of day might not result in the best result, and you would be right (at least with today’s set up).
In order to overcome the brightness of the sun at approximately 1pm I decided that I could attach every filter I owned onto my camera lens at one time. So I did exactly that. Now I do own a Neutral-Density(ND) filter, which acts like sunglasses for your camera lens it blocks some of the light making things seem darker. The neutral density filter I own is rated at -0.3 which means its 1/3 of a stop darker when its attached to the lens. (I’ll try to remember to explain what “stops” are in a different post) After the ND filter I attached a step-up ring and a circular polarizing filter (the step-up ring is just an adapter that lets you use larger filters on a lens, in this case my lens is 67mm in diameter and my circular polarizer is 77mm in diameter). And finally I attached the drop-in filter system I own (drop in filters are usually rectangle and do not contain any threads) and attached the Ultra Violet (UV) filter and the Split ND filter (this is a graduated filter where the bottom half is clear and the top half is a ND filter that are blended together). Finally, I decided to set the apature of the lens to f11 (as with the “stops” I’ll try to go into apature in a later post).
When it was all said and done, I was not able to get the long exposure shots I was hoping for, and combine that with attempting to make panoramas out of the attempted long exposure shots I failed miserably. So instead of just trashing the shots and starting over another day I decided to play around in PhotoShop and create some funky images out of the results. I’ve posted the crazy images to my “Campus Images” photo folder on my Google+ account so you can find them there. If I’m not in your circles on G+ or you aren’t a member, you can see the album here: http://goo.gl/FPoiY
So can shooting long exposures in the middle of the day work? The short answer is yes. The long answer is yeesssssss! In order to shoot a long exposure in the middle of the day you will need a strong ND filter, probably in the range of -3 (3 stops) to -5 (5 stops) and set the apature of the camera to f22 or higher. Also, shooting on a cloudy day would probably work out better as well.
Finally, I just wanted to say thanks for reading to the end of this post. I realize that I probably got a little long winded. And as I mentioned in the post, I’ll try to go into more detail about stops, apature, shutter speed, and why do you want to (and how to) shoot long exposures in later posts.