What's it all about?

This blog is about photography and photoediting. Its purpose is to provide hints and tips and links to interesting and useful resources for digital photographers, regardless of their level of expertise or experience. It is aimed at people who use digital SLR cameras and who process their images using the latest versions of Adobe Photoshop and Adobe Photoshop Lightroom.

The author of this blog is Glenn Springer and you can read more about him at his web portal at faczen.com. Information on workshops, and links to everything is at photography.to. Glenn's original blog, which is an ongoing journal of his photographic meanderings goes back to 2006 and contains many additional hints and tips, as well as representative images that he has made. Gallery quality prints are available through his Smugmug gallery site. It is an interesting place to visit to see a variety of quality images, as well as an ongoing general journal of photos going back several years.

Photography workshops are scheduled every few weeks starting in the Spring. For an overview of what's happening, please visit the photography.to website.

The most recent blog post is below. Scroll down to the bottom to see the list of previous postings or search for any particular topic.

Sunday, April 3, 2011

Using HDR for interior (architectural) shots

I had my bathroom renovated and thought I would take a few pictures as the work progressed. I did, and you can see some of the steps on my Journal blog at http://www.faczen.blogspot.com/. Search for “renovation”. When it was all done, I wanted to take a shot that would show how nice the room looks now. And in the process, I realized that this was the perfect opportunity to use HDR.

In this writeup, I’m going to go through the main steps that took me from an ordinary photo to an image that I think captures the essence of the renovated room (OK, I know it’s a bathroom, and the ‘essence’ is not what we normally want to experience, but you know what I mean!).

The purpose is to show you some of the things you may want to do when creating an HDR, and a few other techniques for post-processing thrown in. Is this a step-by-step tutorial? No. My goal is to make you think about some of the steps you could take to create a final image and maybe to give you some ideas.

If you've been following my Journal blog, and especially if you're a member of the award winning Richmond Hill Camera Club (congratulations to all on winning the Stu Freedman Trophy at the Greater Toronto Council of Camera Clubs competition this year -- without my help this time! LOL), you would know that I created a presentation on HDR for the Imaging Conference, and I promised to convert it to a blog post. THIS IS NOT IT. But it will tie in nicely when I get it finished!

Is this a really great image? Nah. But infinitely better than the original!

Step 1: Visualization

I wanted to show the textures in the wood, capture the warmth of the lights (an aside here. There’s daylight from a window behind me. I didn’t think it would be enough. Also, the lights are not warm at all: I bought 6500K – daylight – bulbs and should not have. I’ll get some warmer ones and use these in my computer workstation area), and the really great colours of that towel hanging on the door. There are deep shadows on the front and sides of the vanity that I wanted to penetrate.

Step 2: Exposure

The front of the vanity is the darkest area in which I want to capture detail, so it needs to be in Zone III or more. So if I set the wall on the right as Zone V, I should be close. I had the ISO cranked ‘way up at 3200 and the aperture at f/4: as wide as it would go on the 12-24mm lens. I was hand-held – no room for a tripod – I was squeezed up against the wall in the bathtub. In the end, the lightest exposure was at 1/50 second. So I set the camera to 1/200 second in Manual mode, set the D300 to do 5 exposures ranging from -2EV to +2EV and banged off 5 frames in high speed mode.

Step 3: Merge to HDR

I have several programs I can use to do this. I chose this time to use Photomatix 4, directly from Lightroom. This image shows the workflow:

Now just sit back and wait for Photomatix to do its thing. There are a couple of choices you have to make, depending on if you were handheld or on a tripod (aligning the images) or if there was anything moving in the image (remove ghosting) but basically, just hit go.

Step 4: Toning the image

Photomatix is going to present you with some presets to look through. You’re not looking for the one that gives you your final image, you’re looking for the one that takes you closest. You’re going to be tweaking from there. In this case, I thought the “grunge” setting was the closest, although I really wasn’t looking for a rough image. Now you start playing with the sliders on the left. The first thing I did was to cycle through the five smoothing settings and in this case, I thought the most pleasing one was the middle one. The picture looks too grainy and bright for me, though

So I brought the Gamma up, added a little extra saturation and got rid of some of the grain and noise by adjusting the four smoothness controls. The critical one is the ‘Micro-smoothing’ but I didn’t want to crank it all the way up because you compromise apparent sharpness that way. When you’re done, hit “Save and Re-import” and your image will show up in the appropriate folder in Lightroom.

Step 5: Post-production

Well technically step 4 was post-production too, but we still have more to do. You could do some colour balancing adjustments, tweak the exposure, change the noise reduction and sharpness, all that good stuff in Lightroom now, but I wanted to do something else first, for which I had to go to Photoshop. So I did. Since I hadn’t done anything in Lightroom yet, I chose “Edit Original” when presented with that choice.

First Things First. I shot with a 12mm lens at an angle, so stuff is distorted. If you straighten the image to make the edge of the medicine cabinet on the left vertical, then the wall on the right is way off. That’s what you use “Perspective cropping” for.

Select the crop tool, clear any presets, then drag to select most of the image. You’ll get a different menu bar at the top when you do, and you’re going to want to select the “Perspective” tickbox as shown.

Now drag the bottom corners of your selection until the edges align with the features you want to be vertical. You may have to play with this a bit. If it doesn’t come out the way you expected, just step back in the history and try again. Photoshop will now create a rectangular image from your selection. If you used to use a view camera with a tilt lens, this is a similar effect. Click in the image to confirm. Magic!

Note that I could have levelled the image here too, but I like the way Lightroom does that, so I saved it for later. OK, what else? There was quite a bit of colour variation across the image. So I used hue/saturation adjustment layers with appropriate masking to vary the colours.I didn’t want the toilet paper roll in the lower right corner, so I used content aware fill to get rid of it. It didn’t work right away, so I had to take it, and the right wall, to a new layer and work there without distraction from other things in the image.

Since I’m really a fan of Topaz Adjust, I opened a duplicate layer with it and used just a little bit of adjustment – in this case I chose the “simplify” preset as a starting point, to smooth the image more. I added a little extra saturation and noise reduction too. Back in Photoshop, I copied the colourful towel to a fresh layer and boosted the saturation. The lights above the medicine cabinet were completely blown out. I copied them to a fresh layer and used the burn and dodge tools to give them a better look with a hot spot in the middle where the bulbs themselves are. There was still too much green in the image so I did a levels adjustment on the green colour channel.

Back to Lightroom. A little tweaking, crop to 8x10 proportion and we’re done. Here’s the final image:

The total time taken to process this image was about 30 minutes. It took me a lot longer to do it again with screen captures, etc so that I could write this up! One thing that amazes me is the lack of apparent noise, given that the camera was set for ISO 3200! And by the way, this was a small room: the width you’re looking at is only 6 feet and the camera was less than 8 feet from the door in the picture. Love that wide angle lens!

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