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05-31-2016, 10:05 AM   #5101
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QuoteOriginally posted by Stone G. Quote
there are some weaknesses with these cheap filters: Pronounced Purple Fringing in high-contrast situations and a sligtly lower contrast
PF and aberrations in general are due to diffraction (the rainbow effect in prisms) so to the extent you can avoid the greater bending of light rays in the periphery of a lens the less PF you'll have.

I've found that using step-up rings and CU filters of one to two sizes larger than the lens calls for allows using only the center of the filter glass which avoids much of the perceived IQ issues with CU filters. I've settled on 49mm for the Q lenses with good results although the 40.5 rings weren't a problem and kit-up easily.

A lens hood also helps overcome the lack of coatings on inexpensive glass and noticeably helps contrast as well.

With the small size of the Q lenses the extra size of the filter rings isn't a problem. For lenses with rings of 62mm and up it becomes a bit of an inconvenience though to buy, carry and use 2x larger filters.

As for 'grip-ability' -- have you been wondering what to do with that old grip/winder or the stand-off flash bracket? Some fit and handle better than others -- and don't overlook stuff made for the medium format bodies. Made for the Q's, this would be a useful after market accessory.

(Yeah, that one's on bass-ackwards but it works. Would be nice if it had electrical connectivity for the switches in normal position. An' the other's upside down.)

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Last edited by pacerr; 05-31-2016 at 01:00 PM.
05-31-2016, 10:10 AM   #5102
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QuoteOriginally posted by pacerr Quote
PF and aberrations in general are due to diffraction (the rainbow effect in prisms) so to the extent you can avoid the greater bending of light rays in the periphery of a lens the less PF you'll have.
{emphasis added by me}

So, will a smaller aperture result in less PF?
05-31-2016, 11:23 AM   #5103
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QuoteOriginally posted by reh321 Quote
So, will a smaller aperture result in less PF?
I hesitate to make a general statement about that - I'm sure others have a better explanation - but I suspect PF would still be present but just less obvious. Every point of light in a scene passes through every point in the lens regardless of the aperture. My goal is to minimize the number of rays exposed to the maximum diffraction effects at the periphery of the lens(es). Oversized magnifying filters do that.

The typical diagram of light rays passing through a lens is deceptive as it only demonstrates a single, or discrete, ray path making it seem that a single ray only passes through a single point of the lens. In fact, that ray passes through every point in the lens with different effects on angle of incidence and diffraction so aperture can't block all rays. (Hey, you try to explain it then! )



But it's easy to test it for yourself with a specific (your own) sensor and lens package.

Last edited by pacerr; 05-31-2016 at 12:14 PM.
06-02-2016, 10:11 AM - 1 Like   #5104
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Q with 01 lens.

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06-02-2016, 06:27 PM - 1 Like   #5105
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xposted in Cloudscape thematic

#1


#2


#3
06-03-2016, 08:22 PM - 1 Like   #5106
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Morning hike
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06-03-2016, 11:31 PM - 1 Like   #5107
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Q7 + 02

It's not often I have a camera with me when there's a particularly intense sunset developing, and I'm near the water.
Time span = 6 minutes between first and last photo.


Wellington Point dusk 1


Wellington Point dusk 2


Wellington Point dusk 3
06-04-2016, 09:31 AM   #5108
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Spectacular sunset! Well captured with the Q! #3 is my favorite; I like the rocks in the foreground!

06-04-2016, 01:55 PM - 1 Like   #5109
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Mass of daisies in my yard! Original Q and 01 lens.
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06-05-2016, 08:26 AM - 2 Likes   #5110
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Pentax Q and pentax K-01

Pentax Q with big bro K-01 , grand pa Auto 110 and great grand pa ME Super….
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06-05-2016, 10:17 PM   #5111
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In the back yard.
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06-06-2016, 08:50 AM - 2 Likes   #5112
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Q7 + 02



06-06-2016, 01:52 PM - 1 Like   #5113
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QuoteOriginally posted by palarnab Quote
Pentax Q with big bro K-01 , grand pa Auto 110 and great grand pa ME Super….
Take out the ME Super and it's the Island of Misfit Toys!
06-06-2016, 11:00 PM   #5114
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Twelve spotted skimmer, on Flickr.


It's summer when these guys come. Q7 and 06 lens.
06-08-2016, 06:44 PM - 1 Like   #5115
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Q + 02

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