Photo Phorum

4 May 2011 - The Camargue and Panoramas

We had a delightful day in the Camargue, particularly at the Parc Ornithological where the flamingos put an a magnificent display for us.  The day was a photographer's dream, clear, blue and sunny, and we'd delayed our arrival until very late afternoon, hoping to maximise the western evening sunlight on these beautiful birds.  This was the first time I'd seriously tested my new Manfrotto 055XPROB tripod and 322RC2 head, bought online in France.

I'd have to say that the tripod and head are a dream compared to anything I've used before and the pistol grip release/clamp for the head is a wonder.  The tripod itself is as steady as you could ask for the price and the easy adjustment capacity followed by the instant clamp on release of the grip made shooting both still and moving subjects a dream.  I was lucky that the light made short exposures possible, but I'd also tweaked the ISO up to 200, despite the brightness, just to minimise blur for these constantly moving clusters of birds.  

I was very happy with the shots I got of birds in flight, using the servo focus to maximise sharpness.  You can judge yourself from the link for the Picasa web album on the top right of the sidebar how well this all went.

Another photographic challenge on the day was how to take an effective panorama shot of the vast Fort at Aigues-Mort.  This thing is just so wide  that it was impossible to get far enough back to fit it all into my 18mm lens, and the changes to perspective as I rotated to take the necessary number of photos capture the whole width are a bit weird (I was 100 metres back from it and it still took 6 shots to get it all in!).  The only way I could eventually patch together a panorama in photoshop was to construct it in three prestitched bits and then put all those together.  The result, as you can see at the picasa album (The Camargue) is strange and I'm not sure yet if I can put it together any better.  I was probably just too close with the equipment I had and probably had to stand much further back (i.e. in the water) and shoot it with a telephoto or a much wider lens with fewer shots.  Don't know and am unlikely to find out with this particular subject.

However, on the general subject of constructing panoramas, I have learned a few things.  As anyone who has visited cities with monumental towers, churches, skyscrapers knows, photographing these tall structures without weird lens distortions is challenging, often because you just can't stand far enough back to fit them all in.  I have discovered (well, "duhh" you're probably saying) that you can take vertically stacked slices of tall things and reconstruct them into a panorama with photoshop (CS3).  One technique I'm playing with involves making sure that leave space and light on either side of the main image at the bottom (ground) level and as much clear sky as you can manage at the top of the image (although you can probably fake that if you need to.  I shot in landscape mode and rotate them to portrait for the stitching. Photoshop does this nicely for you in File/automate/photomerge.  

When satisfied that it is stitched together satisfactorily - you might have to use interactive mode to get the images in the right place, but if your slices are sufficiently overlapped and carefully framed, using sight markers to carefully align each successive shot, then automation should take care of it - you then rotate the whole image back to portrait.

This is where you see the maximum effect of lens distortion. Go to Filter/distort/lens correction and play with the sliders for vertical and horizontal to make the image diminish less into the distance.  It should still taper somewhat or the final image looks noticably faked.  This part of the process where you leave lots of sky at the top and space outside you object on the sides now pays off, as the distortion sliders consume this space rapidly.

However, the result should give you a great shot of your admired tower not looking like it's been sucked up into a celestial vortex, and something more like what you actually saw with your eyes, which is the real objective.

One more tip - reduce the size of your component images before you start to stitch or you end up with a file so large that your RAM implodes half way through and you can't save your final edit.  I know this from painful experience!

1 May 2011 - Wrong Metering Mode

I've been wondering why my metering has been just off the mark for many of my photos on this trip to Europe.  I was convinceed that I hadn't really figured our how to use my 550D properly and was almost pining for my old EOS 350!  Last night, I was fiddling around with my camera, looking up a few things in the manual that had been puzzling me.  Somehow it lead me to methodically working my way through most of my default settings (I usually shoot in aperture priority), and suddenly I realised that I had the camera set on evaluative metering.  Now I know why I have been only taking average pictures - the camera is set to take average exposures over the whole frame!

I think that will explain the flaring in low light and the muddiness in photos where there is a more complex range of things in the frame.  It also explains why my results have been pretty good where the image is simple (e.g. gothic church towers against impossibly blue skies).

Now things are reset to spot metering to match the spot focus and I will report back on results.

Belgian Bull

Update: I switched from evaluative to spot metering and then tried to photograph some rather beautiful Belgian cows with the late afternoon sun on them with a background of impossibly green fields edged by a glowing yellow field of canola.  Some great results but realised that spot metering is very difficult to use with moving subjects.  I guess you learn something everyday - in this case that no one setting is always right.

April 2011 - Why the photography chat?
This is the space where I want to chat, in a very inexpert way, about some of the technical aspects of my photography.  It will no doubt be utterly boring to most, but I hope to record some of my experiences as I try to improve my photography and as I try to master my Canon EOS 550D camera.  I will also welcome any comments or suggestions from those who know the solutions to my questions or can point out (in the nicest way possible) the stupidity of any of my ramblings. 
I suppose for a start, I should try to set out my ideas of the fundamentals of good snapping: 

1. Choose an interesting subject and decide what is going to be the focal point
2. Know where the light is coming from and how much of it there is available
3. Plan to be there at the right time of day with the right equipment
4. Check out what's in the frame and get your composition right
5. Hold the camera as still as possible 
6. Decide whether you should be shooting on auto settings, aperture priority (my default) or shutter priority (sometimes necessary for fast moving subjects or special effects)
7. Which of the wide angle or telephoto lens is the right one to use.

Of course, not all of these are possible to control at all times.  Sometimes the subject chooses you - you just have to be there - and sometimes you just have to try to make the best of poor light, if your subject is so compelling.  Getting the framing right is always important and saves a lot of later work in your editing program of choice.

Wine Cellar in Aloxe-Corton

Holding the camera still is such an important factor and finding suitable ways to brace your camera to stop shake as you release the shutter is the key to better photographs in most situations but especially in less than bright light.  I carry a small, pocket-sized tripod with me most of the time and this has been a blessing on 3 trips to Europe now.
  
Another useful trick is use your timer settings so that the camera isn't shaken by the act of you pushing the shutter button.  You can go obsessively further with trying to avoid shutter shake - using large tripods with remotes and timers as well as settings that tilt your mirror up before the shot is taken  .................. .  All give good results and use some or all of these things at different times. This photo in the wine cellar is a simple example of a photograph taken in low light without flash and on a slow film speed setting - using my trusty small tripod and the timer (aperture priority, f4, 1.6 secs at ISO 100).  A flash would have completely ruined the shot.


Travel Shots

Early morning at Kintzheim

I've done my usual trick so far and blasted away indiscriminately at every charming or remarkable streetscape, artifact, objet, burg, ruin or chateau.  However, the ratio of good to bad/uninteresting shots has been too great and I'm trying to get myself to pick my mark more carefully and to try to find the time to come back to the really interesting possibilities - taking my own advice and getting there when the light is right - usually early morning (not my forté), late afternoon or evening.  I was really regretting not having brought a large tripod with me (too heavy) as I tried to photograph the full moon rising over Sélestat in Alsace the other night.  I had my camera mounted on my little tripod and that was jammed into a supporting stake in a vineyard high up the hill above Chatenois. I couldn't look through the viewfinder because it was too high, so had live-view switched on .......... . So to add insult to injury and the freezing cold, it didn't work.  It was a great shame not to have captured it but still great to have seen such a spectacular moonrise!

Apsaragus in Beaune Market

Also, with part of the object of this trip being to photograph and write about food for the Canberra Times, our Blogs and for a future book, a good tripod is  indispensable.  It's on my shopping list!  If I had the dollars, a 18-300mm lens would also be on the list, but that will have to wait a bit.




Auto ISO on the 550D

Auto ISO causing light artifacts?

One of the features of the 550D is the capacity to set the camera to auto ISO.  It has a standard maximum of ISO 6400 and can be tweaked up to 12800.  You can also set to auto ISO but define a maximum.  I've found this auto ISO feature takes a bit of getting used to.  Where I have had it set to a maximum of 6400 or even considerably lower levels, I sometimes get very bright artifacts in otherwise well exposed shots.  I have reverted to manually setting the ISO unless I'm shooting in very low light situations where conditions are variable.  My results have picked up considerably having taken that decision.  Any tips on this will be gratefully received.