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02-06-2017, 11:22 PM   #76
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QuoteOriginally posted by W.j.christy Quote
I did, it turned out well.....

Nice shot - and what a doll!
Thank you.

02-21-2017, 12:13 PM - 4 Likes   #77
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I have 6 Helios 44 and found that the oldest (a non MC KMZ preset Helios 44) is the most prone to swirl.

2 unprocessed JPGs (Pentax K50, f2)



02-26-2017, 02:22 PM - 3 Likes   #78
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Some backtracking...
From page 1 of this thread:
QuoteOriginally posted by W.j.christy Quote
. . .
I do have a super takumar 50-1.4, and a FA 50 1.4 but i don't think those will swirl, if they can let me know and maybe provide some steps i can play with?
My S-M-C Takumar 50mm f/1.4 will swirl.
A little.
With a little help.

I've been experimenting with a homemade star shape bokeh "filter". Along with stars, the filter can also add some swirl.
Both shots at f/1.4, first without filter and then with.
(Click pictures for larger size.)





It looks like this is an example of the vignette effect discussed in this thread. The swirl is strongest when the lens is at f/1.4.
With the filter on, the lens loses about 1 stop of light. So my Takumar effectively becomes a f/2 lens wide open.

This was a small scale test. The rose branch was about 60cm from the camera, and the background foliage was from 1 to 2 meters behind the branch. I haven't had a chance to try a larger scene.

With my Takumar I can capture more swirl using a full frame camera rather than my K-7. So those shots were taken with a Canon 5D.

I made my filter by printing a star template and cutting the shape out of black posterboard. Then I inserted the star into a de-glassed filter.






QuoteOriginally posted by BigMackCam Quote
Although I haven't tried it myself, I've seen some great results from other people using both commercially-made and home-made bokeh masks . . .
. . . What would be really cool would be to combine a "swirly bokeh" lens with one of those masks
Yeah, I love animated bokeh and I've had fun playing with my star mask.
I tried the same garden scene with my Helios 44-2. Both shots @ f/2, without filter and then with.


06-20-2017, 11:50 AM   #79
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RMC Tokina f/5.6 100-300mm, wide open. I didn't know this lens could produce bubble bokeh until today. I'm not sure whether the swirl in the bubbles is more from the lens or more from the breeze fluttering the leaves on the distant sunlit trees. I was just going for getting the exposure right for Oscar, who I discovered was chill-axing in the shade of his burr oak tree.



06-20-2017, 01:23 PM - 1 Like   #80
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QuoteOriginally posted by goatsNdonkey Quote
RMC Tokina f/5.6 100-300mm, wide open. I didn't know this lens could produce bubble bokeh until today. I'm not sure whether the swirl in the bubbles is more from the lens or more from the breeze fluttering the leaves on the distant sunlit trees. I was just going for getting the exposure right for Oscar, who I discovered was chill-axing in the shade of his burr oak tree.
That's a cool effect... but is it bubble bokeh (as in, the famed "soap bubble" bokeh)? I have a couple of reasonably-modern super-zoom lenses that produce the "mini-doughnut" effect you have there when used at certain focal lengths and aperture settings. I'd say it's quite different to the "soap bubble" effect typical of some well-known triplet designs, and others where the outer edge of an out-of-focus highlight has a distinctly-bright and (sometimes) coloured edge.

I don't see any optical swirl, exactly, as the shape of those out-of-focus highlights is pretty circular rather than elliptical out to the borders and corners - so I'd guess it's the structure of the scene in this instance.

None of which takes anything away from the entertaining effect of your Tokina 100-300. Nice

Last edited by BigMackCam; 06-20-2017 at 01:29 PM.
06-20-2017, 01:48 PM - 1 Like   #81
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Agreed, what swirl one might perceive, might not be from the lens especially, if at all. And the "bubble" bokeh, doesn't strike me as soap-bubble like either. Instead, it's more like the background trees are immersed in some club soda. I've heard of mirror lens highlights compared to doughnuts, but I it looks more like Spaghetti-Os to me, the hole having much greater thickness than the dough part. Some of the tiny Os in my image have a very bright outer edge, looking a bit like miniature mirror lens bokeh, but the bright border of them is kind of uneven. It was a surprise, but I may have never have previously pointed the lens at a background with lots of tiny bright highlights.

QuoteOriginally posted by BigMackCam Quote
That's a cool effect... but is it bubble bokeh (as in, the famed "soap bubble" bokeh)? I have a couple of reasonably-modern super-zoom lenses that produce the "mini-doughnut" effect you have there when used at certain focal lengths and aperture settings. I'd say it's quite different to the "soap bubble" effect typical of some well-known triplet designs, and others where the outer edge of an out-of-focus highlight has a distinctly-bright and (sometimes) coloured edge.

I don't see any optical swirl, exactly, as the shape of those out-of-focus highlights is pretty circular rather than elliptical out to the borders and corners - so I'd guess it's the structure of the scene in this instance.

None of which takes anything away from the entertaining effect of your Tokina 100-300. Nice
06-20-2017, 02:03 PM   #82
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QuoteOriginally posted by goatsNdonkey Quote
it's more like the background trees are immersed in some club soda. I've heard of mirror lens highlights compared to doughnuts, but I it looks more like Spaghetti-Os to me, the hole having much greater thickness than the dough part.
LOL We need a food-related sub-classification for bokeh balls... doughnuts... Spaghetti-Os... what next?!

QuoteOriginally posted by goatsNdonkey Quote
Some of the tiny Os in my image have a very bright outer edge, looking a bit like miniature mirror lens bokeh, but the bright border of them is kind of uneven. It was a surprise, but I may have never have previously pointed the lens at a background with lots of tiny bright highlights.
I first saw this effect (or a very similar one) on a Pentax DA 18-270 zoom. I'd been using it for at least a couple of years before I took a photo with it that produced the weird bokeh rings, just behind the subject (the photo was of meerkats against a dirt-and-gravel background, as I recall)
06-20-2017, 02:13 PM   #83
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QuoteOriginally posted by goatsNdonkey Quote
RMC Tokina f/5.6 100-300mm, wide open. I didn't know this lens could produce bubble bokeh until today. I'm not sure whether the swirl in the bubbles is more from the lens or more from the breeze fluttering the leaves on the distant sunlit trees. I was just going for getting the exposure right for Oscar, who I discovered was chill-axing in the shade of his burr oak tree.
I'd say it is showing mild swirl here. If you look at the shape of the bokeh balls, a lens that swirls will have the balls closer to the edge of the frame squashed in a way that makes them appear to radiate from the center of the frame. The effect is present in your image if you compare bokeh balls from the upper left to ones near the center but it is much less exaggerated than what some lenses will do.

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