"Grading" bokeh?

[Peeb]

Testing a new (refurb, actually) nikon 70-300 zoom.

I hear folks discuss background blur as if it's objectively gradeable. Maybe it is? All just seems like .... blur, to me.

 

[tirediron]

It works fine by clicking on them. I think it relates to file size. If you resize your images to <1000 pixels on the long side and <500kb, you should be okay.

 

[Derrel]

^^^EXTREME crop of very central area of first photo, bokeh.jpg

I was able to hover,click, then Open Image In New Window and download them. The first shot looks kind of bad in terms of how the lens slides in to the defocused zone on the rose petals--with a rather strong, unpleasant line on the edges of the rose petals. Here is the very,very central area of the first image. This looks like subject motion to me, like wind blurring...but no matter what it was caused by, that is not "pretty bokeh". I see this was shot at f/5.6 at 300mm at 1/125 second, and that confirms my suspicion of wind-blurring, or maybe flash + ambient...the edges are very typical of a dual-exposure, flash + ambient without a sufficient delta between the ambi and the flash....

Bokeh varies somewhat, even within the same lens, based on subject matter, distance, lighting, and focal length, and many experts claim they see differences in bokeh rendering based on whether VR is on, or off. Your second image looks entirely different--so I do not think these two photos are really good comparisons to look at.

I own the 70-300 VR-G, have shot it the past 4 years...it's "okay" in terms of bokeh, but at the long end, it does have a bit of that Coke-bottle/aquarium glass look to the edges of objects. It is in no way anywhere near the 105 or 135 or 200 or 300mm Nikkor primes, but the lens is very light and compact.

 

[Peeb]

It works fine by clicking on them. I think it relates to file size. If you resize your images to <1000 pixels on the long side and <500kb, you should be okay.

Edited them and they popped right up! Thanks.

 

[Peeb]

View attachment 120072

^^^EXTREME crop of very central area of first photo, bokeh.jpg

I was able to hover,click, then Open Image In New Window and download them. The first shot looks kind of bad in terms of how the lens slides in to the defocused zone on the rose petals--with a rather strong, unpleasant line on the edges of the rose petals. Here is the very,very central area of the first image. This looks like subject motion to me, like wind blurring...but no matter what it was caused by, that is not "pretty bokeh". I see this was shot at f/5.6 at 300mm at 1/125 second, and that confirms my suspicion of wind-blurring, or maybe flash + ambient...the edges are very typical of a dual-exposure, flash + ambient without a sufficient delta between the ambi and the flash....

Bokeh varies somewhat, even within the same lens, based on subject matter, distance, lighting, and focal length, and many experts claim they see differences in bokeh rendering based on whether VR is on, or off. Your second image looks entirely different--so I do not think these two photos are really good comparisons to look at.

I own the 70-300 VR-G, have shot it the past 4 years...it's "okay" in terms of bokeh, but at the long end, it does have a bit of that Coke-bottle/aquarium glass look to the edges of objects. It is in no way anywhere near the 105 or 135 or 200 or 300mm Nikkor primes, but the lens is very light and compact.

The wind WAS blowing, so you are correct. Hadn't thought about VR impacting, but that makes sense!

 

[Designer]

I hear folks discuss background blur as if it's objectively gradeable. Maybe it is? All just seems like .... blur, to me.

I think it's more subjective than objective. Compare ugly blur with pretty blur, and while it's easy to say which is the prettier, you still can't put a number on it.

 

[480sparky]

^^^EXTREME crop of very central area of first photo, bokeh.jpg

I was able to hover,click, then Open Image In New Window and download them. The first shot looks kind of bad in terms of how the lens slides in to the defocused zone on the rose petals--with a rather strong, unpleasant line on the edges of the rose petals. Here is the very,very central area of the first image. This looks like subject motion to me, like wind blurring............

Looks more like camera movement as everything has a vertical smear. As if there's two identical images, laid on top of each other, with a slight vertical offset.

 

[Overread]

I hear folks discuss background blur as if it's objectively gradeable. Maybe it is? All just seems like .... blur, to me.

I think it's more subjective than objective. Compare ugly blur with pretty blur, and while it's easy to say which is the prettier, you still can't put a number on it.

I disagree. Background blurring can be not only compared and contrasted, but described and explained with desirable and undesirable elements identified.
However its important to realise that:
1) It's a form of language and communication that isn't commonly used by most people so they don't develop the vocabulary nor skill at describing what they are seeing. With that lack of proper organisation of thought into what they do and don't like within the scene they are thus capable of telling what they do or don't like but are incapable of giving a strong answer as to why.

2) Different photos and situations will render the background differently and thus its possible that a lens which people objectively say has "poor" background blurring qualities can still produce a good quality result.

3) Sometimes the differences are more minor and thus many times are easy to visually ignore or to simply gloss over. As such you can, again, have a "technically poor performing lens" still do well.

4) Sometimes the quality of a photo is more weighted on its content or upon emotional connections to the content than upon its pure artistic technicalities.

As a result of some of these factors (and others) there is considerable variety which can confuse the matter somewhat. Thus there is a degree of leniency in the blurring market for most people; with far fewer being more exacting upon the blurring quality that they desire (that high grade blurring often goes hand in hand with much higher lens prices also affect matters.

 

[Derrel]

The real problem, as I see it with the 70-300 AF-S VR-G lens is the "aquarium glass" look that it suffers from at its longer focal length settings--a sort of softening of the in-focus stuff that really affects its images. I went through a couple of folders last night where I used the 70-300 VR lens, to find a good example of the 70-300 G's major weakness--what I call the "aquarium

glass" or "video-y" look at its longer end. Here's a good example, an automated preview shot that has not had any lens corrections applied to it, just a crop from a full-sized image--which helps to magnify and reveal the "aquarium glass" look that sort of tends to be hidden in a full-frame shot, or a far-view shot: this was shot at 240mm at f/6.3 at 1/499 second, according to the EXIF. Look at her hair and eyes--it's just not fully revealing much detail. At shorter focal lengths, this lens does much better.

I would say that Overread's post #8 pretty much hits the major points about bokeh. If you want to find bokeh comparisons of one scene and multiple lenses, the Manual Focus Forum had some good ones back in 2011 or so. Look for the Helios lenses and "swirly bokeh" as search terms. Oh heck, HERE is just one really, really information-filled bokeh thread with photos and descriptions of the bokeh characteristics some people look at, like double-line boke issues; bright line problems; onion bokeh; aperture shape rendering; and overall effect (pleasing, distracting, nervous, harsh,etc). Pretty sure looking at the top set of photos and reading this will allow you to see exactly how bokeh can indeed be "graded".

 

[The_Traveler]

4) Sometimes the quality of a photo is more weighted on its content or upon emotional connections to the content than upon its pure artistic technicalities.

Holy crap, yes.
As long as the technical elements don't interfere too much with seeing the picture than they should be transparent to the viewer.
The only reason they come up so much here is that they are handy levers to use to c/c a picture and many posters here are still struggling with technical issues.

 

[Designer]

O.K., here's my attempt at grading blur objectively:

Ugly blur = -10
Pretty blur = +10

So you're right! Pretty blur gets a much higher number than ugly blur. The scales have been lifted from my eyes. Thank you!

 

[The_Traveler]

Scales on eyes= -10
No scales on eyes = +10

No we've got it.m

 

[runnah]

Ive never liked a photo more or less because of the quality of the bokeh.