Raging Sloth

Canon Powershot S95 In-Camera High Dynamic Range feature review



Back to HDR section


Update - If you'd like some quick directions on how to do your own HDR pictures with an S95 I put up a short tutorial.
Update - I’ve added another set of comparison shots at the bottom.
Update - I’ve added some comparison shots from the Grand Canyon at the new bottom



I used to use a mid range (for its time) samsung point and shoot camera which I had really good results with in high light conditions. The thing was that in regular lighting conditions and in low light conditions I wasn’t pleased with the results (though they were still a lot better than many cameras I’ve seen.) In fact I found that its performance in those conditions was inferior to my previous sony which I was replacing. Outside of really high light conditions, the Samsung tended to take pictures of equal quality to the Sony but at a much higher resolution and file size. I was getting 5MP worth of quality in noisy 10MP format...

It was around this time that I decided I wanted to get a nice camera and purchased a Canon Rebel XSi (just before the Ts came out.) I love my XSi and am planning to get an ultra wide angle lens for it. The thing is I found I was still bringing my samsung a lot of places due to its much smaller size. So I finally decided I wanted to get a high end point and shoot for cases when lugging around a DSLR wasn’t a reasonable option. Now I’m the proud owner of a Canon S95.

I really like my S95 so far and am not even done my initial playing with it. One thing I wanted to check out right away was the HDR feature. I had bought the camera for its low light performance (which is amazing for a camera its size) but I needed to see if the HDR thing was a gimmick or not.

Comparison photos.



Set 1



These photos were taken around 2pm in the afternoon. The camera was lying on a metal table and the shutter button pressed by hand though carefully to try not to disturb the photos.


Single Shot


building against skyline single shot

In-Camera HDR version


building against skyline, in Camera HDR shot using Canon S95

It is pretty obvious that the HDR really brings out the colour and detail in the sky, trees and roof of the building. You can also see that there is no noticeable ghosting in the image.

I have since had some examples of ghosting with the feature when I’ve tried taking HDR pictures while holding the camera in my hands and also on certain surfaces (really smooth desks) but HDR really isn’t meant to be done while holding a camera in your hands, and even on surfaces where I’ve had ghosting occur it can be avoided simply by being very careful as you press the shutter button.

After the taking of all three exposures I’ve found it takes around 7 seconds for the camera to combine them into the final image which is very fast considering the images are 10MP.

Now the Camera doesn’t have any options to do anything other than realistic HDR but even so with the feature on all the tonal information is stored in the image so “fake HDR” techniques using the single image should come out pretty comparable to combining three images in software.

I have also had some less dramatic results, but that is to be expected depending on the scene being photographed. In general I’m quite pleased with the feature and the Camera will also do auto bracketing in case you want to do HDR manually.

New Comparison shots (Set 2)



Unfortunately by the time I took my in-Camera HDR and regular shots the moment had passed and my auto-bracketed shots were of a much less interesting scene and not fair to compare against (I also tried to get some comparisons with my Digital Rebel XSi but again didn’t get it done in time for the clouds to be lit up like they are in the following pictures. I took a couple of In-Camera shots so I’ve also got an example of what will happen if you aren’t really careful with your tripod...

Regular shot



nonHDR sunset from the suburbs facing mountains

You can see that the fence in the foreground is quite dark and lacks detail. The Camera did however realize that the sky was the focus of this photo.

In-Camera HDR shot



in-Camera HDR image sunset from suburbs looking at mountains

Here you can see all the suburban elements quite clearly and the sky is still fully detailed. I’m kind of wishy washy on whether I like this better than the regular photo but it is a matter of contrast. I think if I was to clean this image up I’d up the contrast and darken the suburban elements a bit, not quite as dark as in the other photo and since the detail is there I would get better results.

In-Camera HDR ghosting



I took a second batch of In-Camera HDR and regular photos. When I did so I was less careful when pressing the shutter button on my camera and got a little wobble going on my Tripod. As you can see below even a little wobble can upset an HDR shot quite a bit. This is of course an issue with a regular bracketing approach to HDR but in that case there are software methods you can use to lessen or potentially remove the effects. For example if I were to take a picture of a flag that was moving in the wind there would be substantial scene differences between each shot. With some software programs I’d be able to select one photo to take the flag data from and experience no ghosting if my shots were stabilized enough. With the S95 the flag would have effects similar to what you cans see below from Camera wobble.

In-Camera HDR with ghosting



Note: it is hard to make out the actual problem with this photo due to the resolution change to make it small enough for the web. Please see below for close up.
sunset hdr picture with minor visible ghosting (it is worse in the full res version)

Close up of In-Camera HDR with ghosting



Close up of sunset picture to clearly show HDR ghosting
As you can see the shots didn’t line up as well as they were supposed to and we get blending of objects at multiple locations. Of course what do you really expect from a Camera that runs on a battery and combines the images in 7 seconds? I don’t want to come off to anyone like I’m complaining about this, the In-Camera HDR is a nice function that makes the process easier for regular people and if used correctly produces very nice photos. It doesn’t produce the same results as a well taken and processed bracketed shot but neither does the auto mode on a digital camera take photos as nice as a professional photographer who tweaks all the settings. Hands down I like this feature.

Grand Canyon shots Bracketing and Auto HDR


So after a long time coming I actually have some more comparison shots. I was at the Grand Canyon on a bus tour that only netted me 3 hours at the actual Canyon so I didn't have time to spend taking a lot of photos of the same thing for comparisons but I do have examples using different scenes. First off I want to show an exposure bracketed HDR photo which worked out quite well. I had the camera set to +/- 2 for the exposures which photoshop elements did not like one bit. It would appear that photoshop elements makes HDR shots by taking what it calculates to be the best exposure for each part of the image and unfortunately it really liked to have the mountains in the background overexposed and looking like crap. As such I bought a copy of FDR Tools which I've found works quite well. This image was taken using a delay and a mini tripod and needed only 1 pixel's worth of adjustment to line the images up.

Exposure Bracketed HDR shot of the grand canyon




Regular Exposure from the photos used to take the shot




You can see the extra detail in the clouds, the sky and the area of trees which is now much lighter. Of course the trees could be lightened digitally but there would be less detail information to maintain picture quality.

Now for an example of where the in-camera HDR has failed me quite miserably...

Ugly in-camera HDR shot




Less ugly auto single exposure




You can really see that the auto single exposure had some dynamic range problems. The sky is totally white and the distance is overexposed. The foreground looks pretty ok except a little overexposed to the right. The In Camera HDR shot however looks outright terrible. It seems to suffer from the same sort of problem I had with photoshop elements and my bracketing shots. It looks like the camera saw that there was more detail in the distance in the overexposed shot but didn't do any sort of colour correction at all. In addition, It didn't capture the sky and it added a bunch of blue and silver garbage to the photo.

Conclusion


The lesson to all this: the in-camera HDR is convenient and does a decent job in most lighting conditions, it does however fall totally flat in conditions with extreme lighting. The dark shadow to the left and the sunlight hitting the right and the distance really was too much for the system to handle. Again I would say that we have to have realistic expectations though. It takes a good minute for my 2.5GHz Core 2 Duo laptop to grind out an HDR image with FDR tools, so for a camera that fits in a pocket, runs on a battery and combines and tone-maps images in around 7 seconds you really have to take what you get. In regular circumstances I've had some great photos with it and it saves me the time of having to tweak things using exposure bracketing. However if you want to take photos in extreme lighting conditions and/or expect top notch results you really need to step up to auto-bracketing.