Getting consistant HDRs? (Photomatix)

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Edit My Images
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This is kind of about the whole process rather than just the editing but I guess this will be the best forum for this...

I shoot a lot of interiors, and often use HDR techniques to bring a more dynamic range as well as add depth and contrast to the image. The problem is... Every single time I do a HDR they turn out differently, and I have to play around in photomatix for ages and even then am often not happy... With lightroom I have a certain workflow for certain types of photos, I raise the shadows, lower the highlights, and the blacks, etc. etc. With HDRs I have to try 3 or 4 different blending algorithms and play with settings which often seem to give random results. I also notice a lot of the time the output image is way too dark and there doesnt seem to be a way to brighten it.

So why is this?? Sometimes I put the images in and I get exactly what I want with X settings, but the next time X settings will be absolutely terrible, and nothing will seem to work.

How can I get more consistant results that would require more consistant editing techniques?


For an example, here is one I shot today. I took 5 exposures (-2, -1, 0, +1, +2) with the brighted being how I wanted the shadows to be, and the darkest being where I wanted the highlights (window) to be. After trying all the different algorithms and playing around with settings I got something that looked ok but still to dark, especially in the high mid tones. So I took one of the original exposures and masked it together in photoshop. Totally taking over an hour...
+2:


+1:


0 (middle exposure):


-1:


-2:


HDR output (natural fused):


final image after blending in photoshop:
 



I am very sorry to see you struggle with that technique
when today's gear may make you jump over DR limi-
nations in two takes… at most.
 
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I am very sorry to see you struggle with that technique
when today's gear may make you jump over DR limi-
nations in two takes… at most.

Sorry I didn't quite understand your reply... Are you saying that I should have only used 2 exposures?

I'm not an expert in HDR, or fully understand how it works to be honest so excuse correct me if anything I say may be wrong but... To get details in the window/lamp and in the shadows the exposures would need to be at least 2 or 3 stops apart from each other. And as far as I know you should avoid making HDRs with more than 1 stop of difference between shots. I could have of course used just 1 stop apart and adjusted highlights and shadows in lightroom but this would damage the file and also produce a lower quality result which is not something I want to compromise on. If taking 20 shots gives the best result I would probably do it.

My biggest problem seems to be that photomatix doesn't understand that the walls should be white, and overall how bright the image should be, but as there is not really a general exposure slider on photomatix it is very difficult to control.
 
Are you saying that I should have only used 2 exposures?

Yes, I do so all the time though half the time it would not
even be required. HDR was a solution to the low DR of
earlier sensor
technologies

There are two points to consider:
  1. the extended DR of newer sensors and supporting
    onboard software
  2. the fewer takes the lesser the margin for errors

Your profile contains not personal nor gear details… I can
not help you more on this.
 
Why not do the HDR Merge in Lightroom, it's a function in CC (PhotoMerge - HDR), then you have the sliders available that you are used to.

BTW I agree with you, you need more shots than 2 for the type of work that you are undertaking, what @Kodiak Qc might be truw, but it would involve shadow and highlight recovery manipluation after the Merge, which a 'true HDR' method does not require.
 
Or use the Nik HDR function if you haven't got CC. You still retain the ability to work in LR.
 
Well the one time I tried doing it in light room it took so long to load I gave up waiting after about 5 minutes (I do have a pretty slow computer), in photomatix it usually loads in around 60 seconds. Maybe I'll give it another try..

But I actually thought the problem might be more regarding how I was taking the photos. Or maybe that I need to somehow inform the HDR software which is the middle or correct exposure. Because it's not always the one in the middle. For example if an image has very few shadows that I want to brighten but a bright window, the "correct" exposure might be the darkest one, not the one in the middle of the 3 or 5 exposures. So I end up getting a very dark output file. If this is the reason I assume any software would have the same problem.
 
Noz03, wie gehts es ihnen? You don't need a 5 shot bracketed for that kind of interior shot. Three at most. In fact, you could get away with your +1 exposure, plus a flash shot exposed for the windows. Then simply layer mask in the flash layer to paint in the window exposure plus some flash exposure on to the walls and shadow surfaces which are facing the camera. This technique would take 3 minutes to edit and produce a more pleasing result.

Also, if you used flash, you would remove those window marks showing up on the wood floor (y)

Besides that, are you saying the Photomatix blend differs each time you blend the same image, or did you mean the result differs from image to image?

You say it takes ages in Lightroom. When merging interiors, select Merge > HDR, then when the dialogue box pops up, select None under deghosting. Click ok after you see the preview to render the merge (takes a bit of time). But, the next time you want to merge images in Lightroom, simply click Ctrl Shift H to action the merge with those settings and without the preview. Should be a lot quicker.
 
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I am very sorry to see you struggle with that technique
when today's gear may make you jump over DR limi-
nations in two takes… at most.

I agree with this if you have a camera with a 14 stop dynamic range there is little need for HDR these days, particularly if you include a bit of fill flash.

I think the problem you are having with HDR output is down to the fact that your base image (middle exposure) is under exposed. Try and use an exposure that is as near as possible to the shot you want as you middle exposure then add to that an equal number of+ and - shots to capture shadow and highlight detail. Use your histogram, preferably with live view, if you have the option, in your example above you need the white wall peak to appear 1/3 of the way in from the right on your base exposure. If you are using a Nikon camera on matrix metering pointed at the window you will need to increase your ev by about 1 stop to achieve this.
 
Why can't you just drop the local highlight in the window - and then lift the shadows? Job done. One exposure would solve it.

Why are you shooting only 1 stop apart? There is something like 10 or 12 stops of range in your picture alsready, so you are producing a massive overlap of exposure range before you ever start. Try taking three shots only at +3 0 and -3 - see how you get on then.
 
Noz03, wie gehts es ihnen? You don't need a 5 shot bracketed for that kind of interior shot. Three at most. In fact, you could get away with your +1 exposure, plus a flash shot exposed for the windows. Then simply layer mask in the flash layer to paint in the window exposure plus some flash exposure on to the walls and shadow surfaces which are facing the camera. This technique would take 3 minutes to edit and produce a more pleasing result.

Also, if you used flash, you would remove those window marks showing up on the wood floor (y)

Besides that, are you saying the Photomatix blend differs each time you blend the same image, or did you mean the result differs from image to image?

You say it takes ages in Lightroom. When merging interiors, select Merge > HDR, then when the dialogue box pops up, select None under deghosting. Click ok after you see the preview to render the merge (takes a bit of time). But, the next time you want to merge images in Lightroom, simply click Ctrl Shift H to action the merge with those settings and without the preview. Should be a lot quicker.

Noz03, wie gehts es ihnen? You don't need a 5 shot bracketed for that kind of interior shot. Three at most. In fact, you could get away with your +1 exposure, plus a flash shot exposed for the windows. Then simply layer mask in the flash layer to paint in the window exposure plus some flash exposure on to the walls and shadow surfaces which are facing the camera. This technique would take 3 minutes to edit and produce a more pleasing result.

Also, if you used flash, you would remove those window marks showing up on the wood floor (y)

Besides that, are you saying the Photomatix blend differs each time you blend the same image, or did you mean the result differs from image to image?

You say it takes ages in Lightroom. When merging interiors, select Merge > HDR, then when the dialogue box pops up, select None under deghosting. Click ok after you see the preview to render the merge (takes a bit of time). But, the next time you want to merge images in Lightroom, simply click Ctrl Shift H to action the merge with those settings and without the preview. Should be a lot quicker.

I agree with this if you have a camera with a 14 stop dynamic range there is little need for HDR these days, particularly if you include a bit of fill flash.

I think the problem you are having with HDR output is down to the fact that your base image (middle exposure) is under exposed. Try and use an exposure that is as near as possible to the shot you want as you middle exposure then add to that an equal number of+ and - shots to capture shadow and highlight detail. Use your histogram, preferably with live view, if you have the option, in your example above you need the white wall peak to appear 1/3 of the way in from the right on your base exposure. If you are using a Nikon camera on matrix metering pointed at the window you will need to increase your ev by about 1 stop to achieve this.


Thanks for all the advice/opinions. Actually I think I just worked out the problem with lightroom, as I was always using the shortcut I think it had no previous settings to go by and got confused but I now tried with the drop down menus and it worked fine! Result was pretty nice as well, very natural looking and easy to control!

To go into a little more detail about using lightrooms HDR module... What is a good workflow to have when shooting for this? As in how to expose the shots? Do they all have to be the same exposure difference? (ie could I use -3, 0, +1 if I had a very bright window I wanted to bring back but not many shadows?). And if I wanted to blend in with a flashed exposure could I include that, or do I have to blend it after in photoshop?

As for Photomatix, I did also try using just the top 3 exposures of the 5 I have, so the middle exposure was pretty well exposed for the walls (aprox 80,80,80 on the rgb histogram), but in almost all blending modes the default image came out extremely dark, especially the walls. I could pull it back somewhat with the very unreliable sliders but that messes up other parts of the image, then more and more sliders need to be tweeked and thats what is causing me the inconsistance in the work and final images.
 
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You can't blend a -1, 0, +3 together. You would get very strange blending results with weird artifacts. I've tried it. Always take the inbetween exposures. There's no reason not to take the full set of bracketing exposures - it's not like it takes a lot of time.

Blending in a flash layer with the merge process will also cause issues (not only with exposure but also with things like white balance, especially if you're not gelling the flash to match the ambient exposure white balance). Always mask the flash exposure in afterwards. You'll have better control and produce better results.
 
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Thanks, I'll keep all that in mind.

One last thing, how do you decide on your exposures? How do you decide the darkest and brightest, and how far apart they should be? Are there any rules for this?
 
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