Blending Time - HDR Photography Part 3

HDR Photography

1. Shooting a HDR
2. Getting it off the Camera
3. Blending Time
4. Final Processing
5. Some Inspiration

Time to Mix Exposures

If you have been following this series, at this point you will have taken some bracketed shots, grouped them together somehow, and then opened Photomatix, and set some options to have your images stacked together. Now we will cover the process of Tone Mapping your image down to 8 bits of information per pixel.

Checking Your Shot

The first thing you need to do is click the Tone Mapping button on the left in Photomatix. This will open the Tone Mapping dialog, with a preview pane to let you see the effect of the changes you are making. Once you have the preview pane available, you should check over it.
The things you need to check for are:

• Alignment issues (even if you didn't use the "Align source images" option, still have a quick check)
• Ghosting issues (black or white "holes" in the image where moving objects appeared)

If you do find some issues, you can either leave them be, and fix them later in the GIMP or Photoshop (whatever your image editing app of choice is) or you can try the blending process again, with some different settings to try and reduce the effect.

Details Enhancer

Now all you need to do is Tone Map your photo, and you are pretty much done. However this is probably the hardest part of the process. There are just sooo many options, which change the results so much. When I first started I had a basic favourite few settings, and I would jiggle the sliders a little on 2-3 options, and that as about it.
After some time of this, and a bunch of rather boring HDR images, I went googling for some inspiration, and came across this set of "presets" from Stuart (whoever Stuart is!) - Stuart's Photomatix Presets. Now there are quite a lot of presets here, and it has taken me some time to get to grips with them all, but the process I used when I first downloaded them, was to go through, and select each one, and see the result for myself in the preview window. I would then choose the one I thought looked best, and make minor adjustments (usually lower the Colour Saturation, and maybe make it a bit brighter or darker with the White/Black level sliders) and go with that.

Now that I have been using that method for a while, I know what sort of results I can expect from different Presets, so if I know a certain look will work with the image I'm working with, I can go straight to that preset, make some minor adjustments and I am done. I have also created some more Presets of my own. Most of mine are minor adjustments of the downloaded Presets, but they work for me in saving time and effort exploring all those sliders every time.

Tone Compressor

The Tone Compressor method of Tone Mapping is not one I have used very much to be honest... I find I am unable to get a good contrasty image out of it, every time I try I end up with an image with flat colours. It does tend to avoid that nasty halo-ing you get with the more "extreme" Details Enhancer methods though. I used the Tone Compressor method on this Project 52 photo - Project 52 - #1 - It Begins, but as I look back on it now, I do find the colours a little flat. Definately have a play around with this one though, it is far simpler to understand, and if you keep an eye on the Histogram as you make changes you will get a good idea of what each slider does.

Hold On To Your Hat

Hold On To Your Hat
Originally uploaded by jezza323

Another from the hip street shot with the Canon Powershot A590 IS point and shoot. This one was taken at 5.8mm (35mm @ 35mm equivalent), ISO 200, f3.5, 1/800"

Went for a walk down to the Queen St Mall at lunchtime to get some shots, this is one I got on the way. Managed to get a couple of others were decent too.

I even managed to get EXIF on this one! Processed as follows:

• Copied RAWs + JPGs off camera
• Converted to DNG with DNG for Powershot 2
• Imported DNGs to Lightroom 2.5
• Edited in Lightroom 2.5 (contrast, exposure, noise reduction, greyscale)
• Exported to JPG for Web

Back to Work With You & Some Tips

Back to Work With You
Originally uploaded by jezza323

Here is the first of a few upcoming street shots taken with the Canon Powershot A590 IS point and shoot digital, running the CHDK software. I am going to try and get my confidence up shooting street with this little camera, before I try getting out with the wider lenses using the DSLR.

I shot this from the hip, using hyperfocal distance and Av (aperture priority mode). The shot lost its EXIF in the RAW conversion (CHDK generates unsupported RAW files) but was taken at 5.8mm (35mm @ 35mm equivalent), ISO 125, f6.3 and 1/60"

By the way, if you want a great read on street photography, check out this fantastic post by "Street Vision", an LA street photographer.

Timelapse - Video

From My New Toy
Originally uploaded by jezza323

Here is the output from my latest ebay purchase. It is a Canon Powershot A590IS Compact Digital Cam. I bought this model as it is able to run the CHDK software, which allows many new features, one of which is to run timelapse scripts.

So this was my first go at a timelapse of something interesting. This was filmed? shot?, 1 of those, from my balcony. Unfortunately the script I used didnt allow the camera to go into long exposures as it got dark, so I couldnt use the full set of images I took, but still, this is about 935 shots for this timelapse, taken at 5 second intervals, and pieced together into a 20 fps film. I used Picasa to create the movie.

Enjoy!

Project 52 - #7 - Wellington Point

Sunrise and The Tree
Originally uploaded by jezza323

The sunrise at Wellington Point in Brisbane is a popular location for local photographers. The sun is rising just to the right of frame in this shot, you can see the orange/red glow off the top of the clouds. This is landmark #7 in my Project 52 Brisbane Landmarks for 2010.

Taken with the Pentax K200D and Pentax SMC DA 18-55 AL II @ 18mm, Kenko CPL, TianYa ND8 and TianYa ND8 Grad Filters (thats a whole lotta filters...I didn't need the ND8 but it was already in the holder from an earlier shot).

Single exposure processed in Lightroom 2.5 with exposure graduated mask, clarity, white balance, contrast, exposure and fill lights adjustments.

EDIT: I just realized I had this marked as landmark #6! It is actually landmark #7.

Getting It Off The Camera - HDR Photography Part 2

HDR Photography

1. Shooting a HDR
2. Getting it off the Camera
3. Blending Time
4. Final Processing
5. Some Inspiration

Off The Card

Now that you have been out and shooting bracketed shots, or bracketed panorama shots, you have at least 3 times as many images on your memory card to deal with. These are the steps I go through when I am getting my shots off the camera and doing the initial viewing in Lightroom.

Import

I import from my card reader using Lightroom's import function. This automatically imports images into my photos folder, under a YYYY\YYYY-MM-DD (ie 2010\2010-01-12) format. You can also ask Lightroom to backup the photos to a 2nd location when importing, very important, and simple to do.

Review

The first thing I do after import, is a quick review of imported images in the Lightroom Library module. I work my way through, viewing every image (only briefly). If I believe a HDR set of 3 (or more) bracketed images is worth processing further, I will select all the images, then I will export each set to its own subfolder, such as "HDR-1" or "HDR-4" as a 16-bit TIFF file (you must not use the compression option for your TIFF files, photomatix does not support it). I then stack the selected images (stacking is a lightroom feature) using the Ctrl+G shortcut. This leaves me with a number of subfolders in my working folder, which need to be processed further. (When doing HDR Panoramas I export all the images into a single folder, ie. "HDR-Pano-1")

Windows Explorer

I will then open up Photomatix on my main monitor (I have a dual monitor setup, with a decent 24" Dell and an old 17" LCD) and Windows Explorer on my 2nd smaller monitor. At this point I will navigate to my first HDR subfolder, select the images I wish to blend in Photomatix, and simply drag and drop them from my Explorer window onto Photomatix.

Photomatix

After dropping some files onto Photomatix, a small dialog asking what you want to do with the images will be displayed. If you wish to just blend them together (as opposed to HDR) then select that, otherwise you will want to choose "Generate an HDR image". You then need to confirm the selected images. Photomatix will then ask you to select some settings to use to generate your HDR.

Generate HDR Settings

• Align source images - If you were not using a tripod, you should check this box. I usually use the "By matching features" method, but if that does not work, then you should also try the "By correcting horizontal and vertical shifts" method.
• Reduce chromatic abberations - I always leave this checked, as the HDR process enhances any CA in the shot
• Reduce noise - I always leave this one checked too, again because the HDR process enhances any noise in the shot.
• Attempt to reduce ghosting artifacts - If you have some people/cars/boats in your image which move between the seperate shots, you can try using this option to have Photomatix attempt to remove them, however it doesnt always work. If you find it results in black or white sections of the image (obvious blending errors where the moving objects were), you should start again and not select this option, you can always fix it in the final image. For this one I usually try the "Moving objects/people" option, because thats what I'm trying to remove. If you have a tree which blows about in the wind between shots, use the "Background movements" option.

Now you are ready to click OK. Photomatix will take a few moments, then display you a rather strange looking version of your image, ready to be Tone Mapped. If you notice anything wrong with the image at this point, such as the black/white sections from ghosting or misalignment of the images, you should close, and start the process again here.

I will leave it there for today, in the next post I will cover the Tone Mapping process.

Wellington Point Pier - Hoya R72

Wellington Point Pier
Originally uploaded by jezza323

Wellington Point Pier at sunrise while the sun was behind a large bank of clouds.

Single exposure taken at 18mm with the Pentax K200D and Pentax SMC DA 18-55 AL II lens. Shot at f8.0, 30 sec, ISO 200.

This shot is Infrared, shot using a Hoya R72 filter. All editing done in Lightroom 2.5 (clarity, blacks, white balance, greyscale, contrast)

I really like the extra contrast you get with the R72 filter. The required long exposure didnt hurt the smoothness of the water either