SX50 – Manual Exposures
From time to time I’ll quote from and/or link to various forum threads we’ve participated in. This article is based on excerpts from recent conversations at Birdforum.net http://www.birdforum.net/showthread.php?t=240202&page=25 Discussions like these include questions and answers from the range of experience, with newbies and skilled photographers freely sharing info and advice. These forums are a valuable resource to us, and are highly recommended.
The Case for Manual Exposure:
I prefer to shoot in Manual mode, generally avoiding all the automatic features of the camera save for AF. I begin by assessing the prevailing light and manually choosing an appropriate minimum ISO for my intended target area. My preset C1 settings set ISO80, Manual mode, full-zoom with aperture full-wide, so in decent light I generally only need to frame the shot and adjust the shutter to expose. With practice this becomes quicker than you might imagine, and not too different than trying to guess how much EV compensation will be required to correct for however wrong and in which direction any given AE metering will likely be. An often overlooked advantage of Canon SZ cams is the “live-view” EVF preview which simulates both exposure and DOF (wysiwyg) when shooting in Manual mode. This puts exposure control back in the hands of the photographer. This behavior is unique to the Canon superzooms afaik, and it’s a priceless feature imo… despite the other short-comings of the EVF.
I’m sure most users will prefer to use one or more of the semi-auto modes in various situations for a variety of valid reasons. Temple prefers Av mode with both the SX50 and SX40, and I also use Av mode occasionally when speed is of the essence. I believe Canon has done a good job with SX50 mode processing in general. They provide users at all skill levels with a capable and flexible camera. But I shoot all our Canon cameras in Manual mode most of the time. So with due respect to the preferences and techniques others prefer, I’ll just explain my own thinking on this and hope not to cause any angst. And then I’ll share some example images which illustrate the benefits of manual exposure.
So, just what’s so different about shooting in Manual mode, as compared to Auto, Program, Av, Tv, or even Sports mode for that matter?
The big difference for me, is that in all the AE modes, exposures are determined by algorithm. And however fast or clever that code may be, it simply does not see with the eye of this human photographer … More often than not AE does not expose my images as I would prefer. Further, depending on the complexity and lighting in the scene, any slight reframing (intentional or otherwise) prior to focus lock can cause the camera to alter exposures (often dramatically) even after EV comp has been dialed in. And, when you half-press to lock focus the AE program also locks the exposure in accordance with whatever “it thinks” is correct or best for the framing in place at that focus point, without regard to what the photographer sees or wants to see. Any subsequent reframing (intentional or otherwise) before releasing the shutter does not automatically re-adjust the exposure accordingly even though the composition may have changed significantly, and no manual re-adjustment or further compensation is possible without also refocusing. So if you lock focus on the Raven’s eye in bright light, expose the deep textures of his black head, and then reframe to include the white Mouse in his talons…you can be pretty sure that all the detail in that poor Mouse’s fur will be blown out in your image. If the exposure is not correct when focus is acquired, the captured frame will not be exposed correctly. These complex auto-exposure calculations are all done pretty quickly I grant you, which can be a major advantage, but it’s obvious that this method simply doesn’t always work so well, with blown highlights, blocked shadows and harshness or imbalance in overall lighting even when clipping does not occur… all being very common in auto exposures. And I find it all rather just too fussy anyway.
In Manual mode there is never any need to fight with (or compensate for) the vagaries of the Auto Exposure program. Whatever metering mode is chosen only appears as a light meter guide display and has no effect whatsoever on the exposure of your image. I can adjust ISO, shutter speed and/or aperture to obtain the desired exposure and DOF for my scene based on what I see in the viewfinder. I can lock focus wherever I choose and reframe as needed without fear of the camera altering any setting I’ve chosen. And I decide what compromises should be made to optimize the quality of my shot.
You must select a reasonable ISO for the prevailing light of course, but you can choose the best (lowest) ISO appropriate to the available lighting and never have to bemoan the Auto-ISO program having chosen a higher one than necessary. And you must also know what minimum shutter speeds you need for a steady camera… which with good technique and the SX50s excellent image stabilizer can often be slower than would be chosen by the camera in AV mode. But by not relying on Auto-ISO and Auto-Exposure algorithms the photographer can pretty easily control all these settings to properly adjust his image prior to releasing the shutter, without any unexpected or unwanted intervention from the processor. And he can have much better confidence that what he sees in the viewfinder is both what he wants, and indeed what he will get.
The camera usually makes all of these settings decisions faster than any human could, and my choice to shoot in Manual mode means that whatever exposures I capture (and any missed opportunities that I don’t capture), will be my fault. But I usually prefer the results I get by making these decisions myself.
The following slides were created to illustrate how the high-resolution IQ of the SX50 expands the optical focal lengths (fov) presented in cropped images. But they also provide examples of common scenes which for reasons of focus, lighting and shadow, could be problematic for the AE modes to expose properly.
Peace, and good shooting everybody.