30 minutes in Mishawaka

Quote:

Originally Posted by Dave Humphries

Hi Jon,

You may dislike me for drawing your attention to this :eek:
But I hope it helps you (and others) recognise when it is a danger and take steps to minimise it.

I couldn't help noticing that you have some background bokeh issues with #5 and #7 - a 'double edge' effect on the grasses - I know because I recognise this from my own experience.

I see from the EXIF data that these were shot with the Canon EF-S 55-250mm f/4-5.6 IS II at the full 250mm focal length and wide open, additional factors contributing to this effect being so visible in these two shots are that you have background grasses of a particular size and these are brightly lit and some are light in colour in front of a darker background tone. With different picture content in other shots, you won't even notice it.

As I said, (sadly) I recognise them from my own experience using my Nikon 70-300mm lens, particularly when used at maximum focal length and aperture - and that experience has taught me that using f/8 or f/11 significantly reduces this nasty 'double edge' effect, compared to shooting wide open at f/5.6.

Further, it helps if you selectively sharpen only the subject in PP (post processing), avoiding applying sharpening or contrast enhancement to these (usually background) troublesome elements. I find this a heck of a problem with reeds too; as they're usually a light yellow in colour and often sunlit, when shooting waterfowl in front of them.

I rarely publish my shots that exhibit this effect, as I personally detest it, but here is a similar-ish (Nikon) example, still visible even after I had tried to minimise it by using f/8 and with careful PP, although that was 4 years ago and I think I do better at hiding it these days (and produce better shots).

Hope that helps,

Dave, Thank you for explaining this. I had a hunch it was due to both extremes on the lens. Don't worry, there is no dislike just appreciation for sharing knowledge.

Cheers