As you would expect as the light level increases my E5 will alternate between increasing the shutter speed and reducing the aperture.I am curious at the way it has been programed to do that.It has been programed to prioritize stopping down the lens over increasing the shutter speed. For example: Spot metering off of my computer desk light bulb the exposure that the program mode chose is iso 200, F10 and 1/1600. I am in regular program mode with no shift.Why would Olympus program it to stop down into diffraction softening f stops while keeping the shutter speed at only 1600?I know I can use shutter priority or program shift to get the exposure I want. I am just wondering if the programming choices made by Olympus are the same kind of numbers used on FF cameras (just an oversight) or if they reflect something that I don't know. Is there a reason it seems shy about using fast shutter speeds? Does it overstress the shutter?If you have a DSLR from a different company does it do the same thing?Just wondering. When I use shutter priority to photograph things like dragonflies or hummingbirds I try to shoot at 1/4000 sec or even 1/8000. Is that a bad idea?Thanks -- Jon

Fullframe cameras (and 35mm SLRs) allow you to go to f22. F10 on 4/3 is equivalent to f20 on a full frame camera. While you do get into diffraction limits a little beyond f18, I challenge you to prove if you can actually see the effects of it in any of your photos. I use up to f16 freely (for very long range telephoto shots) with no regard to diffraction showing a loss of contrast and sharpness in my final result. Beyond that, there can be a loss of contrast and sharpening but this is something that must be weighed against getting all the DOF you want. And at such extremely narrow apertures, that is something that only becomes a concern with close up photography.For any other type of photo, f10 on 4/3 is just fine and not a worry, and again I challenge you to prove it that it is.In the photo below, taken at f16 which didn't get the subject in the back within the DOF like I thought it might (it was the first day out testing the EC14 on the 50-500mm shooting handheld) I can't see any evidence of loss of sharpness or contrast due to using f32 equivalent. The theory and math suggests I should but then the real life evidence suggests that unless you use a very very good lens and a tripod used properly, you can't really show the effects of diffraction very clearly. If you do your tests handheld with a cheap lens, you'll get more softness due to the lens and too slow shutter speeds as you stop down than you will from diffraction. A person might then assume the loss of sharpness is from diffraction when it might not be. While the 1/focal length rule is suitable for most people, you will get the best guaranteed sharpness at double the rule and anything below that can show a difference in sharpness if you print large enough. And you have to consider that much of what people assume about the effects of diffraction comes form the film days. There are ways to overcome the loss of contrast and sharpness of diffraction by using software, which they simply did not have the ability to duplicate by processing film in the darkroom and especially with the photo processing machines at the drug store. The second set of photos below shows an f8 digicam photo (f48) and diffraction is clearly evident, not to mention the haze with 400mm equivalent. Using f8 was a mistake, had been doing closeups before this and forgot to change it back the f2.8 which would have been just fine for this photo. But it was a good opportunity to see what I could do with Photoshop which I was learning to use at the time. If I had taken this with my film camera, there would be little hope to improve the lack of sharpness and contrast if using film because I certainly never used a color darkroom, I had my photos processed with one of those big machines at the drug store. But this is digital and you can do much more with your photos and the two photos show quite clearly that diffraction can be an issue but it can be corrected to some extent.While some images do show some diffraction effects with my 4/3 cameras (pretty much only close up work) it is overall not an issue at all. I rarely see it and when I do I can fix it. I will say that f10 on a 4/3 camera should not be a concern to you at all. It's fine, don't worry about it, and again I challenge you to prove this wrong. But don't make the mistake of trying to prove it by using the same shutter speed and a wider aperture and therefore a lower ISO because a lower ISO will be sharper and then you will assume a difference due to diffraction when there isn't. Sure the math and theory says there should be but it won't be enough to notice unless you print your photo huge.Again, unless you are doing very close up photos or extreme telephoto shots, diffraction should not be a worry to you. There are very few images where you will actually ever need beyond f10 to get all the DOF possible and even if you have to go to f13 or so you should not see any evidence of diffraction limits in your end result. Beyond that you might but you can do a lot with software to correct it.Don't assume anything when hearing the usual information about diffraction because much of it comes from 'the old days' with film and just gets repeated over and over by people who perhaps like to sound knowledgeable about the subject but don't ever actually take photos and process them to show how things really are with the current state of technology.

Nice photos.I guess I should be less cautious about smaller apertures. I will have to try them more often. I have used f16 for macro shots. I will try telephoto. The longest I have is 250mm not the 50-500mm so I don't have the same reach.It still seems strange that the shutter speed in program mode never gets close to it's limit. Program mode does a good job of monitoring focal length and maintaining a 1/'equivalent focal length' shutter speed.I was more curious if anyone knew a reason to be careful about really fast shutter speeds.Thanks again. -- Jon