Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
04-27-2020, 11:35 AM - 2 Likes   #1
Loyal Site Supporter
Loyal Site Supporter




Join Date: Feb 2015
Location: Avalon Peninsula, Newfoundland
Photos: Gallery | Albums
Posts: 704
Combining interval shooting and a neutral filter on waterfalls

Set up a little experiment. Local waterfall is about perfect for pics at the moment. While I like water shots, I find the pure cream you get with just a neutral density filter is not as pleasing as I'd like. So I've been fiddling with combining interval shooting and neutral density filters to get a better effect.

Here is a composite of 10 frames each taken at 1/640sec together with a detail of that shot.




What we get here is a bit of a pointillist effect. Interesting, but probably not with this particular subject. (Surf, maybe?)

Here is a composite where each pic was taken at f14 and and a 6 stop filter mounted leading to .3sec/exposure together with a detail.



While I took a series of 25, I find that compositing about 8 frames (I use Silkypix Pro 10 now though I've used astro stackers in past experiments) seems to give the sort of texture I'm looking for. The horsetail texture reminds me more of sugar streaming than cream which visually I find more interesting. Still need to work with the technique a lot, but it feels like I'm on to something. Others must do this as well, but I don't know the field well enough to figure out where to look for more info.

I won't bother showing a totally creamy shot with the filters set higher--especially with this setting and lighting it's very boring to my eyes.

K-70/16-85mm w/ tripod


Last edited by jgnfld; 04-27-2020 at 12:30 PM.
04-27-2020, 11:54 AM   #2
Pentaxian




Join Date: Feb 2015
Photos: Gallery | Albums
Posts: 7,914
QuoteOriginally posted by jgnfld Quote
What we get here is a bit of a pointillist effect. Interesting, but probably not with this particular subject.
You've likely use composite exposure in live view with electronic shutter enabled. You could also use the INT composite mode that doesn't use live view , ES disabled, won't produce dots in moving waters.
04-27-2020, 12:02 PM   #3
Loyal Site Supporter
Loyal Site Supporter




Join Date: Feb 2015
Location: Avalon Peninsula, Newfoundland
Photos: Gallery | Albums
Posts: 704
Original Poster
QuoteOriginally posted by biz-engineer Quote
You've likely use composite exposure in live view with electronic shutter enabled. You could also use the INT composite mode that doesn't use live view , ES disabled, won't produce dots in moving waters.
I was using interval shooting (1 per 2 sec) with LV and compositing the series in post with SP10 Pro, rather than in camera. I'll look into other combos. Thx.
04-27-2020, 02:33 PM - 1 Like   #4
Otis Memorial Pentaxian
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 36,363
The pointillist effect does not appeal to me, but we all know about matters of taste...


Steve

04-27-2020, 02:34 PM   #5
Otis Memorial Pentaxian
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 36,363
Question...why interval and not multiple exposure as burst?


Steve
04-27-2020, 02:38 PM   #6
Loyal Site Supporter
Loyal Site Supporter




Join Date: Feb 2015
Location: Avalon Peninsula, Newfoundland
Photos: Gallery | Albums
Posts: 704
Original Poster
QuoteOriginally posted by stevebrot Quote
Question...why interval and not multiple exposure as burst?


Steve
Mainly because I left my remote shutter release at home--DOH--and wanted hands off as I was in a muddy recently flooded location and that was the quickest way to get the series of frames. There are others as you note. It's a side issue I probably never should have even mentioned.
04-27-2020, 03:18 PM - 3 Likes   #7
Pentaxian
photoptimist's Avatar

Join Date: Jul 2016
Photos: Albums
Posts: 4,355
QuoteOriginally posted by stevebrot Quote
Question...why interval and not multiple exposure as burst?


Steve
For falling or moving water, the interval time shouldn't be too short. If a globule of water takes 1 second to fall across the frame and you squeeze off a 7 FPS burst, there will be seven nicely spaced copies of that globule. It's a cool stroboscopic effect but maybe not a naturalist one.

Doing interval/multiexposure composites/stacks for slower moving water can require even longer intervals to allow floating leaves or foam to move far enough so that the viewer does not see or notice the multiple copies of each leaf/foam spaced across the frame.

It's not hard to look at moving things in a water scene, count off seconds, and gauge how long it takes for things to move across and out of the frame.
04-27-2020, 05:07 PM - 1 Like   #8
Site Supporter
Site Supporter




Join Date: Dec 2012
Location: Essex County, Ontario
Posts: 643
Great practical advice above photoptimist.

04-27-2020, 06:47 PM   #9
Loyal Site Supporter
Loyal Site Supporter




Join Date: Feb 2015
Location: Avalon Peninsula, Newfoundland
Photos: Gallery | Albums
Posts: 704
Original Poster
QuoteOriginally posted by photoptimist Quote
For falling or moving water, the interval time shouldn't be too short. If a globule of water takes 1 second to fall across the frame and you squeeze off a 7 FPS burst, there will be seven nicely spaced copies of that globule. It's a cool stroboscopic effect but maybe not a naturalist one.

Doing interval/multiexposure composites/stacks for slower moving water can require even longer intervals to allow floating leaves or foam to move far enough so that the viewer does not see or notice the multiple copies of each leaf/foam spaced across the frame.

It's not hard to look at moving things in a water scene, count off seconds, and gauge how long it takes for things to move across and out of the frame.
1. Yeah, a strobe effect would NOT be pleasing to my eye here, though I didn't think about that issue. Will now in the future. The more random pointillist effect I got was just, er, well, mussy to my eye. But the strobe effect would be completely non naturalistic.

2. You know, I did actually vaguely think about that a bit when I told myself not to worry about some small colorful plastic balls that were circulating in the whirlpool. Correctly so. But it was nowhere near as thought out as your thinking here. Thx.
04-28-2020, 09:33 AM   #10
Otis Memorial Pentaxian
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 36,363
QuoteOriginally posted by photoptimist Quote
For falling or moving water, the interval time shouldn't be too short. If a globule of water takes 1 second to fall across the frame and you squeeze off a 7 FPS burst, there will be seven nicely spaced copies of that globule. It's a cool stroboscopic effect but maybe not a naturalist one.

Doing interval/multiexposure composites/stacks for slower moving water can require even longer intervals to allow floating leaves or foam to move far enough so that the viewer does not see or notice the multiple copies of each leaf/foam spaced across the frame.

It's not hard to look at moving things in a water scene, count off seconds, and gauge how long it takes for things to move across and out of the frame.
Thanks for the detailed explanation. The usual suggestion on this site for water blur under bright conditions is for interval merge as a substitute for a suitable ND filter. I have tried a number of approaches, have not seen the advantage of using a set interval, and have wondered if I were missing something.

There are several considerations when merging for water blur, the two most obvious being the length of the exposures and the interval between. Not quite as obvious is the vigor and nature of the water motion itself. For example, I do a lot of non-merged tumbling stream work at about 1/10s - 1/15s and strangely, it is not unusual to get a fair number of droplets frozen at those speeds. Not all the droplets are "dropping". Merging multiple shots at that shutter speed merely multiplies the number of suspended drops.

Here is a short list of observations regarding this technique:
  • If one wants blur, it is good to have blur
  • In terms of blur, a stack of 50 exposures at 1/500s is not the same as a single exposure at 1/10s unless the interval is infinitely short (related to point above)
  • A definitive drop of one meter or more is easier to blur than a meter of drop spread over 10 meters distance
  • If there is a mix of fast and slow action in the frame, the slow parts will be the most problematic
  • There is a limit as to what might be attained by increasing interval length
  • Lake ripples are hard to blur
  • Even a mild ND filter can be an amazing help
  • Some leaves never drift out of an eddy, but may yield to removal in PP

Again, thanks for your comment. It helped remind me of the fine points of why merging for blur can be a challenge.


Steve
04-28-2020, 10:02 AM   #11
Loyal Site Supporter
Loyal Site Supporter




Join Date: Feb 2015
Location: Avalon Peninsula, Newfoundland
Photos: Gallery | Albums
Posts: 704
Original Poster
QuoteOriginally posted by stevebrot Quote
Thanks for the detailed explanation. The usual suggestion on this site for water blur under bright conditions is for interval merge as a substitute for a suitable ND filter. I have tried a number of approaches, have not seen the advantage of using a set interval, and have wondered if I were missing something.

There are several considerations when merging for water blur,...
Steve
Thx. Some points to ponder.

BTW, do you know where these issues are discussed in detail in any written source? As I said originally, I am presently experimenting fairly blind and surely there is experience out there that has been written down. I just don't know where to find it.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, cream, density, detail, effect, filter, filters, frames, interval, photography, shot, technique, texture
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
interval movie on K-50 lowest interval 10sec? dvrapant Pentax K-30 & K-50 2 05-24-2016 12:13 AM
Continuous Shooting, Exposure Bracketing, Interval Shooting etc in B Mode! kamayok3 Pentax DSLR Discussion 8 02-12-2014 01:45 PM
Neutral Density Graduated Neutral Density Filter questions tessfully Pentax SLR Lens Discussion 36 04-11-2013 07:01 AM
Combining ND and CPL filter together? catastrophe Pentax Camera and Field Accessories 6 10-19-2011 02:55 AM



All times are GMT -7. The time now is 04:36 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top