Using HDR Efex for Interior Architectural Photography

Interior architectural photography, for architects, designers, real estate etc presents some challenges for the photographer. As in all photography, control and quality of light is paramount. Lots of time and money has been invested by designers, architects and builders in the use and effect of windows and lighting. As a photographer it is our job to represent those aspects to the best of our ability.

In the old days, this was accomplished with the use of elaborate lighting setups. Firstly tungsten, then leading up to the powerful and portable flash arrangements we use still today. With the advent of digital photography, it became easier to modify images after having taken the. This paved the way for the development of HDR (High Dynamic Range) photography. This allowed the combining of images to be blended together to show the full dynamic range (from full shadow to full highlight) in the one image. In the beginning this led to very surreal effects that bore little resemblance to actuality. Today, very advanced software allows for the use of this technique to be much more realistic.

Why HDR?

So why would you use this HDR technique to photograph interiors In my work, the primary reason is because it allows me to produce an image which is as close to the actual scene. By this I mean all the lighting, both natural and electrical, is shown as it is in reality. Whilst this could be done with using flashes, either large or Speedlite setups, this method is more reproducible and much more cost effective to me, and to the client. Also it removes the possibility of mistake leaving harsh shadows, colour casts and other issues that can arise with the use of flashes.

Technique

the basic technique of HDR photography is to take a series of bracketed shots and put them together using software. My workflow for this is:

• Camera is fixed to tripod with remote release cord attached.
• Camera is levelled using electronic level on screen.
• Scene is metered for middle exposure of room. This is in AV mode @ 100ISO using shutter speed to achieve correct exposure with a fixed aperture.
• Using the Auto-bracket function, I set this to either +/- 2 or 3 stops. This depends on how much difference there is between the brightest and darkest part of the image.
• I usually take a series of 3 or 5 shots depending on the scene.
• Import the images into Aperture after storage on HD.

Software

I have used Photomatix in the past, but over the last couple of years I have been using HDR Efex by Nik Software. I have found this to be much more user friendly and also more subtle in its method effects and tone processing.

Once the 3 images are selected and imported into HDR Efex, you are presented with the following workspace:

This shows the imported image in  the centre, with various built in presets down the left. To the right are the tools used to modify the image. This has settings for normal image control like contrast, exposure etc. and also tone compression and HDR method controls.

The default setting that is applied to the image when the window opens is remarkably effective as-is. Most of the presets are not much use for my needs as there effect is too extreme and therefore too obvious. You can also save your own preset once you have a series of settings you are happy with.

The first thing I usually do is adjust the sliders to achieve the correct exposure, contrast and saturation for the room. White balance is adjusted if needed once the blended image is back in Aperture. This will usually result in the windows being blown out and over exposed, in this case due to the time of the day, the windows were not so bright so just needed darkening a little. This is achieved through the use of 'Control Points' accessed through the panel on the right:

 Once you click on the 'Add Control Point' button you can click on the image and add one. What this does is allow you to selectively control parts of the picture in terms of exposure, contrast, saturation etc., as can be seen here on the right hand window:

So by lowering the exposure and playing with the other setting, you can drop the relative luminance of the brighter areas. What I have found is using many control points with smaller changes to each produces the most accurate result. As with all HDR work, it is a matter of trila and error to obtain the best settings for each particular occasion.

A handy feature is you are able to show a masking images that shows exactly where the control points are affecting:

 So by using the control points to modify the parts of the image you want, the control over the image is remarkable. You can easily achieve a realistic and accurate looking image in very little time:

In this case this is a subtle change but this technique works in almost all situations.

Once you are happy with the image, just click on 'Save' and a tiff of the modified image is saved and, in the case of Aperture, opened there. this can be further worked on there if needed. Sometimes it may need to be run through a noise reduction software (I use NoiseNinja) but if all exposures have been taken at 100ISO then it usually is fine unless the images is going to be displayed at a very large size.

The End

I hope this helps people interested in HDR for interiors. HDR has been given a bad name by some people for various reasons, mostly because of the surreal effect it can bring. As I have shown taking the correct bracket shots and subtle use of software tools provides extremely good results. If anyone would like more information on this, please let me know.

Low Light Event Photography with the 1DX

Had a couple of indoor events for the Halogen Foundation, a charity helping produce the young leaders of the future. various speakers appear and speak on leadership.

Was a good tryout for the low light, high ISO and focusing properties of the 1DX. All in all it seemed to do pretty well!

I started off playing about with setting the ISO, but given changing lighting conditions and the darkness of the arena, compared to the stage, I wanted to control shutter speed and depth of field as much as possible. In the end, using the auto ISO setting was the easiest way to accomplish coverage of all the differing luminances. The values produced ranged from 3600 up to about 20000! Given the high end of this range, there was surprisingly little noise present in the images. Obviously it was there in the shadows, but given the ISO speed it was quite remarkable. What this did allow of course, was the ability to gain depth of field when needed and provide a shutter speed at which all shots on all lenses could be comfortably hand-held.

In terms of focusing in the dark arena conditions, sometimes the camera did flater, but given it was almost too dark to see the crowd, it was still impressive without and AF-assist beam of some kind. Fast glass helps of course, but even the best have their limitations - MF to the rescue.

In terms of white balance, I did start using the Tungsten setting, which worked well for the first event where the lighting was almost exclusively that. However the second event was an awful mix of Tungsten for the stage and low-light fluro and Tungsten on the audience. Talk about a rock and a hard place! In the end for those shots I just shot Auto WB, which gave a faithful rendering for most, but some required a tweak in Aperture afterwards.

In terms of pure WB for the stage lights, the Tungsten setting worked perfectly and colour was rendered very accurately.

The dynamic range of the 1DX was very large, which allows for beautiful gradation of tone in both the shadows and the highlights. This is definitely the best low-light camera I have ever used. When combined with f2.8 L lenses, I cannot hope for a better combination and provides the option of coming back with shots that would not have been possible before without supplemental lighting. the naturalness and colour rendition is second to none in the Canon stable.