ronpier Loc: Poland Ohio

I do the “two finger spread” on my IPad. If it stays sharp, it’s sharp. Look at the eyes. The eyes will tell you right away if the image is sharp. Failing this test will probably end up in my trash can unless it is a unique one of a kind image.

Fredrick Loc: Former NYC, now San Francisco Bay Area

Thank you, Paul. One of the simplest and clearest definitions of BBF I’ve ever read. I’ll never understand why camera manufacturers don’t include a definition like that in their user manuals.

CHG_CANON Loc: the Windy City

Thank you Fredrick! I've found Back Button Focus is pretty much a photography slang term for a usage scenario / specific camera configuration, the type of thing never covered by the manuals. Similar would be ETTR - Exposing To The Right. The manuals might give some examples of Depth of Field of larger vs smaller apertures, but never talk about the impact of metering to the left or right of the 0-mark, nor even what to do get the meter back to the 0-mark.

Manuals are almost exclusively 'what' each control on the camera does, very little 'how', and never 'why'.

imagemeister Loc: mid east Florida

This should be REQUIRED reading for any and all photogs !
.

CHG_CANON Loc: the Windy City

If you have to lower your expectations to fit your results, so be it.

R.G. Loc: Scotland

Do sharpening and denoise together, and find the optimal balance at 100% (1:1). If they're optimised at 100% they'll be optimised at any level of zoom. However, even after that process you may find that at normal viewing distance you can "get away with" some extra sharpening - it's one way to eke out some extra vividness when you think a photo will benefit from it. Anyone who has well rounded PP skills will be familiar with the difference between pushed and overcooked. It's also true that even if a photo has been fully optimised globally, local adjustments can still be used to target specific areas - either problem areas or areas where some extra tweaking is required.

Jules Karney Loc: Las Vegas, Nevada

yes

anotherview Loc: California

Yes. But some say that a viewer should stand at a short distance to judge a photograph. This stand-back will naturally reduce perception of sharpness in a photograph.

I believe judges in a photography contest view a submission at 100% to determine its degree of sharpness.

Ourspolair

I think that 100% does well, but I also go to 3-400% when examining how well I did when using manual focusing. The secret to sharpness is in the initial capture - appropriate shutter speed to lens f/l and taking the time to select the appropriate aperture and focus point to achieve the best DOF for the image. I sometimes fail to use a tripod when I know I should, forcing up the ISO and increasing sensor noise which will have a negative effect on apparent sharpness. Also don't forget that maximum "sharpness" is not appropriate in some shots... A softer look is sometimes more appealing. Please stay safe over the holidays and keep on sharing.

ronpier Loc: Poland Ohio

All very good points. Thank You.

amfoto1 Loc: San Jose, Calif. USA

How large you should view an image on your computer screen entirely depends upon:

- The size of the original (in pixels).

- How you'll be using the image.

"100%" is often ridiculously large. 200% would be absurd in most cases.

If you're using a typical computer monitor, it will display approx. 100 pixels per inch. If your camera is 24MP, it makes images that are 4000 x 6000 pixels. "At 100%" means an image will display one pixel on screen for each pixel in the image. So that 24MP image will be sized as if it were 40 x 60". Hello! That's FIVE FEET WIDE! Do you actually plan to print the image that large? Even if you do, you won't be viewing it from 18 or 20" away, the way you are your computer monitor.

If you size the image for printing using 300 pixels per inch, which is very high quality and beyond what's needed for most printing processes, that same 24MP image can be directly printed as large as 13.333 x 20" without any re-interpolation. Viewing the image at around 33% is closer to how that would look. Many printers say 240 pixels per inch is more than enough for high quality prints, in which case you'd be able to make a 16 x 24" print without any need for re-interpolation.

if you size the image for online sharing it will need to be scaled down quite a bit more, typically to around 100 pixels per inch times however large you want it to appear on screen. For example, a 2000 x 3000 pixel image (6MP) will appear quite large when uploaded here on UHH. 25% viewing on screen should be more than sufficient. But in many other online uses even viewing the original image that large would be overkill. Re-interpolating the image smaller will increase it's apparent sharpness.

So "at 100%" on screen you're often looking that the image far larger than anyone else will ever see it and are viewing it far closer than it would be if truly printed large.

If your camera is lower or higher than 24MP, adjust accordingly. Also, all this assumes no cropping of the image, but that's another discussion and for best possible images we should minimize or try to avoid cropping anyway (get closer, use a longer focal length, etc.).