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Message: <blockquote data-quote="tdodd" data-source="post: 1693813" data-attributes="member: 55450">You're welcome <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile    :)" loading="lazy" data-shortname=":)" />Another thought - I mentioned high shutter speeds, for hand holding, but how high? Well you may be familiar with either of two rules of thumb for minimum hand held shutter speed....- Shutter speed must be at least 1 / focal length, so you should not shoot a 400mm unstabilised lens at less than 1/400, when hand holding;- Shutter speed must be at least 1 / (focal length x crop factor), so you should not shoot a 400mm unstabilised lens on a 50D at less than 1/640.Those are good rules of thumb, but some people are able to shoot at slower speeds, while others may need even faster speeds in order to achieve shake free images.But actually there is more to it than that. The speed you need also depends on how large you intend to make your images for final display, and whether you crop them in software before producing the finished article. What really matters is your enlargement factor. The more you enlarge/magnify your images the more easily the flaws will be revealed. Those flaws can include shake, blur, noise, misfocus, insufficient DOF, diffraction - a whole bunch of stuff.The original rule of thumb worked well for shooting 35mm film and printing to around 10x8 or perhaps 12x8 as a maximum. The rule applies equally to images shot on a full frame DSLR, because the sensor is the same size as the film and to get a 12x8 print will require the same degree of enlargement : approx 8X.When you shoot with an APS-C body you end up with a significantly smaller image from the sensor - 1.6X smaller. Thus to get a 12x8 print from an APS-C body requires the image to be enlarged by a factor 1.6X greater and the captured image will need to be 1.6X sharper. That means that shake and blur need to be 1.6X less, and the easiest way to accomplish that is to raise shutter speed by 1.6X to compensate. You'll also find that your focusing needs to be 1.6X more accurate too, and you might find you need sharper lenses as well. That's why you are better off shooting at 1/640 with a crop camera in order to match the sharpness from a full frame camera at 1/400.But it doesn't end there. What if all you need is a web shot to be displayed at a pysical size of just 6x4 on a screen? Well you've just halved the size of your problem. If you needed 1/640 to make a sharp 12x8 you will probably get away with 1/320 for a web sized image, so long as you don't crop your original. If you do crop your original then you end up with a smaller image to start with, so whether you need a 6x4, a 12x8 or something else, you'll find you may need to shoot with a different minimum shutter speed again.Finally, when you pixel peep at 100%, you are creating a virtual image that might easily be 40" across, and maybe a lot more. If you want your individual pixels to look sharp at 100% then you'll be looking to use a shutter speed of something like....1 / (focal length x crop factor x 4)which means shooting at 1/2500 for a 400mm lens on a crop body. That may start to run you into issues with aperture and/or ISO, if you pursue that approach. This is where tools such as stabilised lenses and tripods can really help out. How much easier to shoot from a tripod at 1/320 than hand held at 1/2500. That will buy you three stops of extra EXPOSURE, which might mean shooting at 200 ISO instead of 1600 ISO. That will help IQ enormously.This is another reason why you should aim to fill the frame as much as you can. The larger the subject captured at the sensor the less cropping you will need to do later and the less pressure you put on your IQ and your own skills, because you will end up enlarging the image less to create your final piece of work. This actually goes on further, to support the recommendatoin to get closer. The closer you are the shorter the lens you can use. The shorter the lens you can use the lower you can set your shutter speed. The lower the shutter speed you need, the lower the ISO you need etc. etc.. Of course, there are other issues when changing subject distance and focal length, such as perspective and subject isolation from the background, so sometimes it is better to shoot from farther away, but then you really need that long glass to do the work for you, rather than cropping until there is nearly nothing left of the image you recorded.EDIT : If your 50D images don't look pin sharp at 100% then don't feel like you have failed. If your image looks sharp at 50% then you should consider that to be an excellent achievement. Even at 33%, from a 50D, that will be an image of 1584x 1056 pixels, which will pretty much fill most people's monitors. That's still a big (almost huge) enlargement, and if it looks sharp at 33% then you will have succeeded in producing a fine piece of work, as far as sharpness is concerned, at least <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite1" alt=":)" title="Smile    :)" loading="lazy" data-shortname=":)" />.</blockquote>

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