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08-29-2015, 09:00 AM   #1
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1st attempt with HDR function

Had a beautiful CuNim off to the north last evening so I thought it a good time to try the HDR function of the K50. The camera was mounted on a tripod and a remote release was used. I tried all three +/- settings and all the shots came out with the same image displacement. Is there something wrong with my camera or was I just asking too much of it?

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08-29-2015, 09:19 AM   #2
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guessing there was enough of a breeze that things weremoving even if your camera wasn't. The road is fine, but the clouds are ghosted. The HDR settings were too aggressive, which is where the haloes around the trees come from.

My take would be that the in-camera HDR functionality isn't very good (I've never tried it). Try taking 3 exposures yourself and use some software to combine them

Nik HDR Efex Pro is my favorite, though I don't like the examples it's showing there. It's easy to use, not as easy to make a really awful HDR shot with, but it's not great at handling ghosting sometimes.

HDR Photography Software - Standalone Programs & Plugins by HDRsoft is a very fully featured product, it's excellent at letting you sort out complicated ghosting issues, and it produces a lot of really terrible HDR shots in the wrong hands. Go easy on it if you try it. Less is more. Don't let the sky look like Gozar the Gozarian is about to step out of it (and if you do, remember that if someone asks you if you're a god, you say YES)

You can also merge to HDR in lightroom or photoshop. The picture will look pretty much the same as the middle exposure did before, but instead of having +/-5 stops, you'll have +/- 10 stops of dynamic range to dodge and burn with.
08-29-2015, 10:34 AM   #3
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Good Morning,

I have never used the HDR mode directly, but I have done a lot of "HDR" using bracketing. I recognize the problem here well, as it has plagued me from time to time. Since HDR or bracketing is taking multiple shots with varying exposure values, there is time spent from shot to shot, plus each shot if of a different shutter duration. What happens is movement of the object/scene that you are shooting, which when the multiple shots are blended together - you get a less than stunning result.

I was fortunate enough to be able to shoot the USS Constitution in the Boston Navy Yard (after hours) at both sundown (and after) as well as sun rise (and before). I did the sunset first and learned a very high priced lesson. I wanted the highest quality, and best detail in the shadows - so I shot at a very low ISO (80) from a tripod (If I would have though things through a bit more I would have perhaps recognized my stupidity). What I failed to realize (or actually remember from being in the Navy), is that the tide and wind, bounce the ship around like a cork - even when tied up to the pier.

So, when I processed the shots later that night, my heart sank when I scrolled shot to shot, and it looked like a movie of the ship rising with the tide and moving with the wind. It was even worse when I combined them together. The pier, pilings and background was perfectly sharp. The ship was blurred (just like your clouds), the rigging looked like a set of banjo strings. It was crap. So, when there is the potential of movement, RAISE the ISO - you can always process out the noise to varying extents. By raising the ISO, you capture more light and the exposures are substantially shorter. I was able to take the best single exposure of each bracketed group and just process it as a single frame, so I was able to recover to a degree.

I don't really understand the internals of the HDR mode - but if it tries to minimize the use of buffer memory (which I would think that it would), it would take an image, do a bit of processing, take the next image, do more processing, take the final image and then complete the processing. At least in bracketing, it just takes 2, 3 or 5 successive images in quick succession with no processing in-between (which I used) and I still had problems.

So, the bottom line is you have to understand to a degree of what the camera is going to do, and also the environmental factors (weather, etc.) surrounding the scene, to really make it work for you.

Just a note - it does look like you were at a pretty high ISO level with the grittiness of the images. There are times when HDR/bracketing just does not work out well. The best approach is with single frames that have good exposure characteristics, and then post process them well to pull out the information that you were able to capture.


Last edited by interested_observer; 08-29-2015 at 10:42 AM.
08-29-2015, 10:53 AM   #4
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HDR is just a type of image stacking. Good results depend absolutely on all the elements of the image being stationary in respect to each other. The camera or the blending algorhythm can align the images if they are shifted one frrm another but it cannot align elements within the image.. What has happened in this case is that the clouds have moved in between frames while the road and other parts of the image have remained relatively stationary and the processing software in the camera just can't put it together. There is nothing wrong with your camera or lens.

08-29-2015, 12:31 PM   #5
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Can you tell us anything about the settings used (aperture, ISO, exposure time)? Did you use "green mode" or one of the manual ones? And in case of the latter, do you feel confident in your abilities to dial the correct settings?

The reason I'm asking is because your pictures seem really strange to me. Not only did the clouds move unnaturally far between exposures, your ISO also seems way too high.
Did you bump up ISO intentionally because you needed super short exposure in order to freeze the fast moving clouds?
Maybe you used the wrong settings and somehow dark frame compensation or some other PP kicked in and delayed the second frame.

I recommend not going above ISO 400 for HDR, ideally you'd stay at base ISO. Disable *ALL* in-camera post processing (diffraction/aberration correction). Dial back noise reduction. When the frame is static, use optimal aperture. With moving subjects, open up as wide as possible.

Last edited by romay; 08-29-2015 at 12:43 PM.
08-29-2015, 03:30 PM   #6
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I'm also surprised because I've found the in camera HDR in both my Kr and Q (haven't tried it in the K5 yet) to actually work quite well, even hand held.
08-29-2015, 10:08 PM   #7
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I'm going to guess that shake reduction was on. Turn off the shake reduction if mounted on a tripod. Try it again.

This is one of the downsides of having shake reduction or any camera with ibis or lens with stabilization. Gotta remember to turn it off.

08-30-2015, 05:38 AM   #8
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I personally have used the HDR processing in my K500 a couple of times, but I prefer to shoot in RAW and the in camera process will not work on RAW images.
I have found that Photo Matrix Software does a very good job of removing ghosts from blended photos especially if there is movement and I've attached the elements of a shot I did of a flower and later processed the with the software
The first 3 photos attached are the original bracketed shots. The camera was Hand Held with the shake reduction on.
The 4th shot is a layered merge of the 3 shots using Photo merge Exposure in Elements 13 which is essentially the same process as the camera that did not remove the ghosting caused by the movement of the flower between shots. It is my understanding that the ghosting can be removed with PS Elements but it would take a lot of extra work
The final shot was processed with Photo Matrix Essentials. The software, I feel, effectively processed the original raw files and removed the ghosting caused by movement from the primary focal point.
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Last edited by NS_Sailor; 08-30-2015 at 06:21 AM.
08-30-2015, 06:06 AM   #9
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The camera chose to use ISO 21600 and f11 at 1/4000. It then took three shots in a burst and processed them afterward (a progress bar comes up on the screen and the camera is locked up while processing the three images). The only thing I changed was the amount of the step between shots. If my notes followed my shooting, not always perfect, this one was at +/- 3. Hadn't thought of image stabilization as a problem. If I get the chance again, I'll turn it off next time.
08-30-2015, 06:44 AM   #10
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QuoteOriginally posted by LSAGuy Quote
The camera chose to use ISO 21600 and f11 at 1/4000.
Shooting at such a high ISO and shutter speed will most likely reduce or even eliminate the effect of ghosting caused by movement but the settings will introduce noise into the final photo that even the camera's internal noise reduction process may not remove
08-30-2015, 11:11 AM   #11
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QuoteOriginally posted by LSAGuy Quote
The camera chose to use ISO 21600 and f11 at 1/4000. It then took three shots in a burst and processed them afterward (a progress bar comes up on the screen and the camera is locked up while processing the three images). The only thing I changed was the amount of the step between shots. If my notes followed my shooting, not always perfect, this one was at +/- 3. Hadn't thought of image stabilization as a problem. If I get the chance again, I'll turn it off next time.
I really don't think that any of the individual shots had a movement problem. The difference is way too clean and clear cut. The movement came between the first and last shot, and it was substantial. Parts of those clouds were moving - quickly. Regardless of any of the settings - anything would have had the same problem.

I just looked and the frame rate for the K50 is 5 fps. So, you needed 3 frames in a burst. The shutter speed in this case is negligible. Therefore, the entire process - involving the shutter took 3/5 of a second or 0.6sec plus then HR processing. The only way to "fix" the problem is with a higher frame rate. 10 fps would cut the amount of movement in half, but it would still be noticeable. The only real solution would be an electronic shutter.

08-30-2015, 12:49 PM   #12
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Taking another look at this I don't think the motion is due to wind. It looks like vertical displacement in the cloud and the edges are very even and consistent unlike what would be expected if the cloud were driven by the wind. I can see shake reduction causing that kind of displacement.
08-31-2015, 05:30 AM   #13
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Well, then there are a couple of things that probably have gone wrong - if you used +- 3EV and your base exposure was 1/4000 at ISO 21600 then probably the underexposed shots came out bad since the camera can't co 3 stops below 1/4000. This doesn't really explain the displacement, though.
If 1/4000 was your darkest exposure then the brightest one was shot at 1/50, but this still doesn't explain displacement.

My guess is that either noise reduction kicked in because of the high ISO and delayed one or more frames or your buffer ran over. I don't have enough experience with the K50 to say whether the latter is possible in HDR mode at all.

Some tips:
1. Always leave enough "headroom" in your HDR bracketing so that the camera doesn't run into limitations. In your case, 1/400 would have been okay as base exposure, this would have allowed for a much lower ISO. Also, +-2EV is isially okay, if you really only want a punchy sky then you can deliberately underexpose your HDS one or two stops at the expense of the shadows and foliage on the ground.
2. Dial back ISO as much as possible, since tonal compression (HDR processing) by definition amplifies noise a lot.
3. Pro tip: This is actually my secret for awesome HDR pics: When doing HDR, *never ever* base your exposure on what the camera meters on its own. Instead of that:
- Select spot metering, dial ISO back to base ISO.
- Meter exposure for the brightest and darkest spot in your scene. If the darkest spot yields unacceptably long exposure, dial up ISO carefully and repeat the measurements.
- Once you're satisfied, calculate the EV range.
- For static scenes, divide that range into equal amounts of 2 EV and setup your bracketing accordingly.
- For "moving" scenes, use 3 EV intervals and narrow the bracketing window by one EV on both ends.
- Make sure you're in RAW mode and have JPEG disabled, along with all other PP features like noise reduction or lens correction.
- Take your shots and don't mind if not a single one is properly exposed, that doesn't matter.
- Use your favorite tool to stack the images. Don't pull up all sliders, just compress the tones to a point where it starts to look unnatural.
- Dial back the sliders a bit.
- Make sure you output a 16 bit TIFF and no JPEG. Finally, run it through noise reduction and lens correction.
- Feed the result into your standard PP workflow.
Awesome results guaranteed.
09-11-2015, 05:15 PM   #14
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QuoteOriginally posted by NS_Sailor Quote
Shooting at such a high ISO and shutter speed will most likely reduce or even eliminate the effect of ghosting caused by movement but the settings will introduce noise into the final photo that even the camera's internal noise reduction process may not remove
I agree. I'd put it on a tripod, SR off, and manually set the shutter speed and ISO. You'll get significantly better results. I've shot them handheld as a test, but in bright daylight so the shutter speed was fast.
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