Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
08-06-2013, 10:31 PM   #1
Loyal Site Supporter
Loyal Site Supporter




Join Date: Jun 2009
Location: Tumbleweed, Arizona
Photos: Gallery | Albums
Posts: 5,314
Question - ISO, Bracketing, Shutter Speed and ev

Good Evening Everyone,

Last year I was able to shoot the USS Constitution during (very early morning to) sunrise and sunset in to the late evening. I need to go back to Boston on business for a week of design reviews late in September, so I want to try this yet again - given that the Navy is willing to entertain my request again.

Last year, I was able to get some excellent images, but not the one(s) I was really after. My largest problem was I took my usual approach of shooting for the highest quality (ISO 80 @ f8), and as I lost the light, the exposure time just elongated as expected. What did not dawn on me at the time, was the tide and breeze - which slightly moved the ship and introduced a slight "motion" blur. Its really amazing to flip through the images and watching the ship bounce around, with the rigging looking like banjo strings.

One thing that did work in my favor slightly, was I was shooting 5 frame brackets (+/-2ev), so I had the ability to select from a range of images.

So this time, I want to take a slightly different approach. Obviously increase the ISO - but to what maximum while still retaining the best quality possible (I want to print possibly at 20"x30" if I can)? I really want the shot, but at the smallest amount of noise possible - but need the ship as rock solid as possible. I was at 20 to 30 seconds (at ISO 80) a last time, so I am thinking that 400 - 800 - 1600 may produce the desired results - depending on the weather conditions (I also need to check the tide tables for the dates/times). In reviewing the lost shots, 30 sec was way too slow. Several at 10 sec were good, then again several at 5 seconds were just as bad as 30 seconds.
  • ISO 100 - 30 sec
  • ISO 200 - 15 sec
  • ISO 400 - 7.5 sec
  • ISO 800 - 3.25 sec
  • ISO 1600 - 1.625 sec
  • ISO 3200 - 0.8125 sec
I'm considering increasing the ISO to 800 in order to increase the relative shutter speed to something less than 5 seconds.

I was really happy with the depth of field at f8 (the lens' sweet spot), but also considering going to either f5.6 or f4 (which is pretty much wide open for my 8-16 and 12-24). I know that the lenses are wide enough that I probably don't need to consider DoF at all. So, if I am using the ISO 800 at 3.25 seconds as a base, then:
  • f8 - 3.35 sec
  • f5.6 - 1.625 sec
  • f4 - 0.8125 sec
I am thinking that 3 seconds (and below) would increase my probability of a good shot to 70-80% (up from about 5%). I am also wondering if the combination of ISO 400 at something like f5.6 which should bring the shutter time down to 3 seconds too, along with hopefully minimizing the noise. Suggestions and comments? Just how much would you ratch up the ISO (at 8 to 9 pm)?

The other approach I was going to continue with was bracketing (5 frames) - but not for HDR. Rather than +/-2ev, I was going to use +/-0.3ev. I really do not need a wide dynamic range (highlights or shadows), but to burn off 5 frames in quick succession with slight exposure variations around a central mean. This was the unexpected bonus from last year, that I had enough shutter speed variation to at least salvage quit a few shots. Also the exposure modes - I usually use Av, but with -
  • P: Varies exposure time and aperture (depending on the program line)
  • Sv: Varies exposure time and aperture
  • Tv: Varies aperture
  • Av: Varies exposure time
  • TAv: Varies exposure time and aperture
  • M: Varies exposure time and aperture
I am wondering if I should consider TAv so as to be able to capture some shutter speed variations, which might increase the number of useable images. Any thoughts on this would be very welcome?

Another thought. If I were to use Av mode and say f8, ISO 400 and a shutter speed of 7 seconds, but dial in an ev of -1, how would it treat the shutter speed?

I am pretty sure of the answer on this question - but does any know if the K5 can vary the ISO in bracketing (automagically)? I am pretty sure that it will not - but the Pentax Collective is a very astute group.

In searching the web for images of the Constitution - I have found most to be pretty mediocre, with perhaps 10 to 20 (out of thousands) really being stunning. I am trying to get just one really stunning one (for my office wall). Anyway - its good to have goals - even if they perhaps may be unachievable. I might also be pushing my skill level here - but the unexpected has happened before.....



08-06-2013, 11:20 PM   #2
Pentaxian
calsan's Avatar

Join Date: Nov 2008
Location: Perth, Australia
Photos: Gallery
Posts: 1,408
DOF is affected by distance from the subject and aperture, ONLY. Wide angle lenses appear to have "more" depth of field because you can fit more of the subject in. But if you took a 300mm lens (say) and were able to back away sufficient to fit the whole ship in the frame, it would provide the same depth of field as using a 12mm lens with the whole ship in the frame, assuming same aperture.

Speaking of long lenses, if you are able to use a longer focal length and get further away, it will flatten out the perspective and maybe give you a more classic look to the photos.

It's interesting how things we think of as immobile, thanks to photography we learn that they aren't. Trees comes to mind - a shutter speed of 1/250th or faster is generally necessary to get a sharp shot of a tree.
08-07-2013, 04:03 AM   #3
Loyal Site Supporter
Loyal Site Supporter
foto guy's Avatar

Join Date: Apr 2008
Location: Vernon, Connecticut
Photos: Gallery | Albums
Posts: 282
You'll get the highest quality shooting at the native ISO of the sensor, which is not necessarily the lowest ISO.

That said, there are plenty of programs that are effective at reducing noise, so increasing ISO a couple of stops shouldn't be an issue.
08-07-2013, 05:50 AM   #4
Loyal Site Supporter
Loyal Site Supporter




Join Date: Jun 2009
Location: Tumbleweed, Arizona
Photos: Gallery | Albums
Posts: 5,314
Original Poster
QuoteOriginally posted by calsan Quote
DOF is affected by distance from the subject and aperture, ONLY. Wide angle lenses appear to have "more" depth of field because you can fit more of the subject in. But if you took a 300mm lens (say) and were able to back away sufficient to fit the whole ship in the frame, it would provide the same depth of field as using a 12mm lens with the whole ship in the frame, assuming same aperture.

Speaking of long lenses, if you are able to use a longer focal length and get further away, it will flatten out the perspective and maybe give you a more classic look to the photos.

It's interesting how things we think of as immobile, thanks to photography we learn that they aren't. Trees comes to mind - a shutter speed of 1/250th or faster is generally necessary to get a sharp shot of a tree.
Thanks for the comments and suggestions. The area around the ship is pretty confined, and across from the mooring there are obstacles that would be in the foreground. I did get some shots using an 85mm lens and its too is really too long other than for details. I do think that you bring up an interesting point though that I have not seriously considered. I was going to bring a 25mm/f2.8 along with my 50/1.7 (its small), and these could possibly create some additional opportunities, both from the focal length and larger aperture prespective. From the pier-side, you loose the waterline entirely, so, from across the channel with the right perspective, this might work rather well.

QuoteOriginally posted by foto guy Quote
You'll get the highest quality shooting at the native ISO of the sensor, which is not necessarily the lowest ISO.

That said, there are plenty of programs that are effective at reducing noise, so increasing ISO a couple of stops shouldn't be an issue.
I have read posts speculating that the base ISO for the sensor is anything from 100, 160 to 200. Last year, I was also trying to capture as much dynamic range as possible - since it was night, the most obvious but perhaps not the best strategy (shot myself in the foot). This year - given the experience gained from the last outing, I am thinking that anything up to say 800, that will provide the best possible combination to capture the best image is probably the main goal. Your suggestion on the noise reduction utilities is excellent, and would provide a good safety net in post processing. I usually don't need them, but that would just re-enforce the notion to shoot probably a combination of ISO 400 - 800, probably giving the camera a range of 100 to 800, shoot TAV and let the body optimize the parameters. That coupled with bracketing +/- 1/3ev across 5 frames, would provide 5 separate "optimized" opportunities, to capture an excellent image.

My goal is just one, absolutely stunning jaw-dropping spectacular image. But, I would also be very happy with something that my skills can actually achieve. I believe that the subject, location and opportunity will be present - its just the matter of composing, framing and not making a stupid mistake - on my part.




08-07-2013, 07:32 AM   #5
Pentaxian
halfspin's Avatar

Join Date: Aug 2012
Photos: Gallery
Posts: 255
DxOMark measured that using 80 ISO on the K-5 is actually 70 ISO giving it the most dynamic range possible for the sensor (14.12 Ev). Everything they measured for (color sensitivity, tonal range, etc.) is best at ISO 80.
08-07-2013, 10:27 AM   #6
Loyal Site Supporter
Loyal Site Supporter
JimJohnson's Avatar

Join Date: Jan 2012
Location: Summer:Lake Superior - Michigan Winter:Texas Hill Country
Photos: Gallery
Posts: 2,299
I am one of those thousands of mediocre shots of 'Old Ironsides', so I really can't offer you much new. On each of my visits to this national treasure I have found the sailors at the Boston Harbor Naval Yard to be friendly and very accommodating to visitors - but doing a sunrise to sunset shoot from a fixed spot is way more cooperation than I would have expected.

One of my issues in photographing this grand dame of the sea has always been the limited sight lines. I can photograph parts of the ship, but getting the entirety in one one image is tough. Please do post one (or several) of your shots!

I'm leaving for Chicago later today. One of my goals is to photograph the congregation of tall ships visiting Navy Pier this weekend. Wish me luck!
08-07-2013, 05:38 PM   #7
Loyal Site Supporter
Loyal Site Supporter




Join Date: Jun 2009
Location: Tumbleweed, Arizona
Photos: Gallery | Albums
Posts: 5,314
Original Poster
QuoteOriginally posted by JimJohnson Quote
I am one of those thousands of mediocre shots of 'Old Ironsides', so I really can't offer you much new. On each of my visits to this national treasure I have found the sailors at the Boston Harbor Naval Yard to be friendly and very accommodating to visitors - but doing a sunrise to sunset shoot from a fixed spot is way more cooperation than I would have expected.

One of my issues in photographing this grand dame of the sea has always been the limited sight lines. I can photograph parts of the ship, but getting the entirety in one one image is tough. Please do post one (or several) of your shots!

I'm leaving for Chicago later today. One of my goals is to photograph the congregation of tall ships visiting Navy Pier this weekend. Wish me luck!
Afternoon Jim,

I just returned from picking up our youngest son from NAU this afternoon. He turned in his last paper yesterday, grades posted today - he is officially graduated and starts his new job on Monday.

The only reason I asked the Navy was because they offered. On the USS Constitution's website, they have a page for Events & Services request, so I requested and they very kindly and graciously obliged. The only reason for my request was indeed the limited sight lines, and you need to be up close in order to get the full image from the water line to the top of the mast. I just showed up at the agreed time, they explained where I could not go, and let me go photograph. For the sunrise, the Chief (Public Affairs) was there and was shooting pictures with me. The facility is manned 24 hours by 7 days a week, so the Navy was there regardless.

Here are links to some of the images I was able to capture last year.I will say that I did break the piggy bank for this and went out and picked up a Sigma 8-16 so that I could capture the ship from waterline to the top of the masts. I did the math and that is the only rectilinear lens that would work - and I wanted straight rigging so a fisheye was out.

I did not know about the Chicago event. That sounds like a lot of fun. I hope that you are able to capture some great images. When you return - please post!!

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!
aperture, av, camera, exposure, f8, images, increase, iso, photography, sec, shutter, time
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Video mode and manual shutter speed/ISO ? alamm001 Pentax K-01 10 12-12-2012 04:49 AM
ISO shutter speed technique alamo5000 Photographic Technique 3 11-15-2012 03:54 PM
How to set shutter speed with ISO.. JWS Troubleshooting and Beginner Help 6 07-06-2012 08:20 PM
Decreasing EV to get faster shutter speed? shang Pentax DSLR Discussion 18 01-29-2011 07:57 PM
k10d flash and shutter speed question vsmouli Pentax DSLR Discussion 7 02-24-2010 02:55 PM



All times are GMT -7. The time now is 12:52 AM. | 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