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Message: <blockquote data-quote="tdodd" data-source="post: 1869196" data-attributes="member: 55450">Richard, viewing a file from a 7D at 100% is very, very different to viewing a file from a 1D3 at 100%, because the pixels from the 7D are smaller and more densely packed. When you view at 100% you are viewing pixels of a fixed size on your monitor and so the tiny pixels from the 7D are under greater enlargement (magnification) than those from the 1D3 when displayed on a monitor. Taking my monitor as an example, I have a resolution of 1920x1200 and the screen width is 14.5" wide. If I take a file from a 7D and display its 5184x3456 pixel image at 100% it is equivalent to blowing up the image from that cropped sensor to 5184/1920*14.5 = 39" across. Bearing in mind the sensor is only 22.3mm wide that is an enlargement factor of approx 45X. If I take my 3888x2592 pixel image from my 1D3 and display it at 100% that is equivalent to displaying the whole image as 3888/1920*14.5 = 29" across. Yet I started out with a larger image to begin with, with a sensor width of 28.7mm. That means I am only enlarging the 1D3 image by a factor of approx 33X. In other words the 7D file is enlarged by a factor almost 50% greater, and that will more easily reveal problems with misfocus, shake, blur, noise, insufficient DOF and diffraction. To make fair comparisons between cameras it is only right to compare images at equivalent enlargement factors. You need to determine which camera makes the better PICTURE, not which camera makes the better PIXEL. Making comparisons at 100% is not comparing apples with apples. I might also add that if you do view at 100%, thus yielding a virtual image of 39" across (it could be a lot more on many monitors) then ordinarily you would view such an image, if printed or displayed on a TV screen, from a distance of at least 4', not 12"-18" as is typical when viewing (scrutinising) a computer monitor. A while back I ran my own tests, comparing the results from my 1D3 against my 40D and 50D at a whole range of ISOs from 100 up to 3200. When viewed at equivalent enlargement factors there was not much to choose between them. When viewed at 100% of course the 1D3 trounced the 50D at the pixel level. Pixel peeping has its uses for analysing the outright quality of an image, but it is not much use for comparing cameras with different pixel densities at all. All IMHO. <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite2" alt=";)" title="Wink    ;)" loading="lazy" data-shortname=";)" /> It's also worth noting that the old guideline of 1/(focal length x crop factor) for minimum hand held shutter speeds was pretty good when printing at up to around 10x8 or maybe 12x8. It is probably not good enough, unless you are very skilled or lucky, for examining individual pixels at 100%, or 39x26 or more. If you want sharp BIF at those sorts of magnification you may need shutter speeds 3X to 4X faster than the old guideline suggests. Best thing to do - think less about pixels and more about pictures. EDIT : Here you go - here are three images at 800 ISO (a reasonable BIF ISO) from my 1D3, 40D and 50D, in random order. They were shot from the same tripod position with the same prime lens. I have cropped them to create an identical (or as close as possible) composition and then resized them all to an equal size. That means that regardless of physical pixel dimensions, the enlargement factor is the same for all three cameras. For reference, the 1D3 file was cropped to 1071x714 pixels before resizing to 800x533. The other files of course have more pixels in them for the same field of view, but the pixels are smaller, so in theory it should all balance out. Let's put theory into practice.... EXIF is intact, but I suggest you make your own judgement about the results before looking to see which file is from which camera. They were cropped and converted from raw in Lightroom 3 with no edits.</blockquote>

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