I want to get a ND filter, but I need it quickly before heading out on a trip. B&H and adorama are shut down for the holidays, and some sellers through amazon sound like they won't really ship for a couple of days, so even if I do expedited shipping, it might not go out in time.
Two questions:
1. If I'm shooting waterfalls, what ND filter strength should I get?
2. Where can I buy it from and get it by Saturday?
I don't have another online merchant suggestion, but if you happen to have two polarizer filters you can stack them to achieve much the same effect -- in the crude experimental examples here I was able to achieve (slight under-)exposures of up to four seconds in full daylight.
It will depend upon how bright the scene is to begin with. I use a Hoya ND8 that works for general stuff, but there have been times I've wanted to drag the shutter more. Having said that, it's probably the most generally useful ND (IMO). It cuts 3 stops of light. I've used Cameta in the past and the service was good.
How much of an ND you'll need will depend upon how bright you expect your ambient to be and what aperture you're intending to use, and you may be interested in something like a 9 stop ND, but this will be of limited use for other things (I use my ND filter for cutting light while maintaining an open aperture, but 9 stops is a bit much for most of my applications in that sense)
I don't have another online merchant suggestion, but if you happen to have two polarizer filters you can stack them to achieve much the same effect -- in the crude experimental examples here I was able to achieve (slight under-)exposures of up to four seconds in full daylight.
Nope -- the problem is that my lenses are all 77mm, and the camera stores don't seem to stock that size. :(
So the nearest camera store that may have one is over an hour away. (Small town, here.)
I'm still trying to figure out the .6 .9 1.2 8, 12, 16 stuff. Some say .9 is three stops, some say it's 4 stops. Some descriptions say 12 is three some say 4. I'm not quite sure what it all means, but I'm thinking a 1.2 or 16?
Depending on the speed of the water and the amount of blur you desire your shutter speed is going to need to be in the area of 0.5 seconds to 2.5 seconds.
Let's say your are in bright sun light, proper exposure using Sunny 16 would put you at f/16 with a shutter speed of 1/125. So you need to cut 6 stops to get to 0.5 seconds and 8-1/3 to get to 2.5 seconds.
If it is over cast you would be around f/8 at 1/125. If you set your aperture to f/16 that gets you two stops so your ND filter would need to be in the 4 to 6 stop range.
Seems like a 6 stop ND would work for most situations and then just adjust your aperture to get desired shutter length.
I hope my math is correct here, can somebody verify?
FYI... I remember someone (I think it was BearMusic) posting a method for achieving a similar result by stacking multiple photos.
FYI... I remember someone (I think it was BearMusic) posting a method for achieving a similar result by stacking multiple photos.
I think you can use a tripod and burst mode, then stack the images and mess with blend modes and/or opacity, or maybe use HDR (I also want to experiment with stitching) software but with the images all having the same exposure. If there's no wind moving leaves, the moving water should blur but nothing else.
This is an unadjusted resized original shot at 4 seconds, f/8.0, ISO 80 on a sunny mid-afternoon using two stacked polarizers (I bought a second one used for $10 just for this purpose). Camera was on a mini-tripod and the FL was 291.6mm (35mm EQ) so I think there's also some camera shake, but as you can see the exposure is pretty much OK as a starting point.
This one was shot at 2 seconds (unadjusted) (adjusted)
Once you find what you want order from Amazon. You can have it by Friday.
I was having a hard time finding the stronger ones on amazon -- they were sold by third party dealers that didn't ship right away.
Ended up buying a 6 and a 3, figuring I could stack them. I found a 10, and was wondering if it would be too much, and if I'd regret it. Probably should have done that instead, but we'll see what happens.
It's kind of strange, though. It was hard to find anything over 3. I looked at midwest photo, calumet, richmond camera, and a bunch of other camera stores from which you could order online, but they seemed to stop at 3 with the 77mm.
Well, the 6 and 3 will give me something to play with. Thanks for the info, everyone!
I bought this variable one from Henry's a year and a half ago and have been pleased with the results. The variable nature gives some options for adjusting exposure length.
I think you'll be fine with the 6-stop and 3-stop combination. Remember, if you need more exposure time but can't get it, you can always stack in post, per my instructions in the thread linked by Mark. When you are stacking the filters, be careful of flare and ghosting, it can get bad, you've got a lot of surfaces there.
Your going to want to probably use your 70-300mm or your 28-135mm. Most of these falls are pretty open. All have good shade, but then we've been hitting them in the afternoons. I've been using my 18-270mm with a .6 NG Filter. So far getting pretty good results (IMO). If you use your 100-400mm you will loose quite a bit in the wide view (not sure if I'm saying that right)...you will want to get more of the "big" picture. Some isolation works but most of these falls are tighter (how close you are to the falls) and smaller. Kind of like the ones in VA that we saw.
I tried a "quick and dirty" experiment with this -- there's a small creek nearby and I just rested/braced the camera on a rock and shot in burst/continuous mode at 1/30 sec exposure, f/3.5, ISO 80. I ended up stacking 6 or 7 frames; I only had to move a couple around a little bit. I found I had to set the opacities of the overlying images a bit higher than in the post ...
Unadjusted base image Stacked result: (I don't think I made any other adjustments).