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I’ve again stumbled upon someone claiming that one Raw is as good if not better then bracketing when making a HDR image…
Thought I’d debunk this ones and for all.

This is the bracket I used in this example, it’s from -4 ev to +4 ev, 9 exposures.

Out of those 9 exposures I made this HDR in Photomatix Pro 4. There are virtually no clipping just some pixels directly in the sun.

This is the middle (0 ev) Raw file.

This is the HDR from a single Raw file, using the same settings as in the above, both the white and black end are clipped, there are lots of noise and loss of detail. The shadow areas that are without details are turning grey because of the tonemapping tries to compensate for black, it could be pulled down but that wouldn’t change the amount actual dynamic range, just make it harder to see.

And finally this is the middle exposure Raw file converted without ever going to HDR, but using every slider in my raw converter to pull out every last bit of information. There are clipping in both highlight and shadow and excessive amounts of noise, but to my surprise, the detail in the shadow area are greater then the single Raw HDR.

Still, the dynamic range in this is no where near what it is in the multiple exposure version. There are times when using one single Raw file is the way to go, for example if you have moving targets, but generally bracketing gives you a wider dynamic range with much less noise.

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A little about photography…

Focal Lenghts

I am spending some too much time on flickr and one of the most common questions people post there is what lens should I buy… often they need a lens that can do everything, is fast and cheep and made by the same company as their camera… I have covered 10 to 500 millimeter in my camera bags so I decided to put up the tripod in the garden and show what the different focal lengths actually looks like. I made these steps 10, 20, 28, 35, 50, 80, 135, 200, 300 and 500. I shot all photos with an aperture of f/8 and with a Nikon D300 that has a magnification factor of 1.5 so the range is 15-750 mm if you use a film 135 camera (The numbers under the images in parenthesis are for FX or 135 format). The lenses I used is  Sigma 10-20, Sigma 18-200 and Sigma 150-500.

10mm (15)

20mm (30)

Wide angle (10 & 20 mm)

10mm is considered a “Superwide” and 20mm is a Wide focal length. Theses are good for landscape and at least 20mm for architecture. 10mm is so wide that you get distortions if you put the horizon on any other place then the middle, and yes you get distortion even if the lens is the brand as the camera…

I like to use these focal lengths for infrared works too…

28mm (42)

35mm (52)

Normals (28 & 35 mm)

28mm (42mm in 135 format). This is as close to the “normal” lens I get here… The normal is actually not 50mm as is the common belief, but about 29mm on DX cameras, 43mm on FX or film if you like. “normal” is the focal length when the perspective is the same as we perceive with our eyes when we look at a scene. 35mm is approximately the same as the famous 50mm lens on the 135 system.

50mm (75)

80mm (120)

Short Tele (50 & 80 mm)

This is short tele range on the DX format, every time I say that 50mm is a I get some shit for it but really… On an analogue or FX camera it can be called a “normal” but not on a DX… 50mm is a good lens for portraits (or so I’ve heard)

Nikon has a very good lens, the 50/1.8, it’s sharp as a razor has very little distortions and cost about a 100 euros… There are no reason not to carry that around.. =)

135mm (200)

200mm (300)

Tele (135 & 200 mm)

For better reach, sports or events where you can’t get close enough, 135 would probably still be a grand portrait lens if you have space… these lengths start to get that compressed perspective effect that tele lenses have and it’s fairly easy to blur out the background…

300mm (450)

500mm (750)

Long Tele (300 & 500 mm)

Sports and wildlife, birds, that person you are stalking… Generally these are heavy big pieces that you know why you are carrying around… =)

When you get to this length you will need a very short shutter speed to not cause motion blur, at 500mm I started noticing mirror shake too… It’s harder to use very long lenses then people generally think…