Exposure and Histograms

[Martin P Wilson]

I usually shoot raw and I noticed this weekend when converting I was having to bring in the black and white points as the histogram was not using the full dynamic range available (good, no clipping). I was shooting powerboat racing under a sky that varied from clear blue to cloudy but mostly bright with a high level haze. So I had a subject with a full range of tones. The histogram was nicely centred so my exposure was pretty well spot on but why the limited range? Pictures OK, if a bit flat, I just had spare dynamic range at each end.

 

Anybody have any thoughts? I was using a Canon EOS-1Ds3 and the results were much the same on raw or in-camera jpg.. I can't think of a way of changing exposure to extend the dynamic range the sensor records.

 

I am currently reviewing my workflow to support news/sport where, ideally, I will need to be able to submit in-camera jpg from the field without post-production (I will shoot raw+jpg). I was having to expand the range to avoid dull images. Not a problem normally as I can make adjustments at leisure and so I had not really noticed it before.I will have to dig out the camera manual, there may be a setting I have missed.

[Bryan]

I've noticed this when using a telephoto, maybe just not as much contrast as when using a shorter lens - more air to cut through perhaps?

 

Further, some subjects don't have much contrast, particularly when combined with flat light - I don't think that it is anything to worry about. 

 

I notice that within Canon's DPP raw converter there is a contrast control, which I suspect can also be set in camera, but never touched it myself!

[Martin P Wilson]

Thanks Bryan,

 

Contrast should have been OK even though I was using a longish (400mm) lens but fairly close. It was essentially a bright clear day (1/1000 @ f8-11 on ISO400). I have just had a thought that if I have the highlight protection setting thingy on that might be doing it. I must find the manual!

 

I wasn't so much worried as wanting the in-camera jpgs to be usable without having to post process - I need to reduce time (and effort)  from shot to submission as time oi of the essence if I am going to maximise sales opportunity through Alamy News et al. For instance at sports events I want to be able to submit pix between races/ classes when typically there is a maximum of 20-30minutes p[ause in the action.

[Martin P Wilson]

Just had a quick play - highlight tone priority might be contributing to it. Unfortunately the light is rather flat today so I can't really check properly. Switched it off and will see what happens.

[David Davies]

Have you tried different camera profiles?

[Martin P Wilson]

David,

 

I think that may be it. I had it set to Faithful as I have almostly used the camera with raw and it gives the most flexibility. According to the manual (just found) Faithful is "dull", Standard appears from a very quick test to be more contrasty with a wider histogram. It was so long since I last reconfigured the basic settings I had forgotten all about picture styles - doh!

 

I will now need to watch my exposures more carefully.

[Paulstw]

As far as I was aware the in camera profiles, styles and settings don't effect the RAW file at all, only the in camera conversion to JPG. I always try to shoot to the right as much as I can as the RAW files tends to 'dull' down in Lightroom in an auto tone import. 

[Martin P Wilson]

Paul, You are probably right. I have always shot raw so I wouldn't have noticed. But now I need to be able to use the in-camera jpg so will increasingly be shooting raw+jpg as I want the control of raw to maximise quality on those images that justify the effort and where I have the time to process.

 

Recently I have been trying to expose to the right rather more diligently. Which is how I came to be very much more aware of the compressed histogram; and using a Fuji X-E1 which seemed to make better use of the dynamic range.

 

In the quick test I ran the  Standard jpg was slightly wider than Faithful (and the raws) and the shape was different. There was some difference between the raw files but it was a not a critical test. I will see how it works for real when I get the chance.