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Old Baader VenusU vs New BaaderU

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#1 Andrea B.

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Posted 12 February 2018 - 01:22

The D300 has no internal filter so I popped in the old 1.25" Baader VenusU filter to make a test photo of this Bidens flower which has a classic UV-absorbing bulls-eye.

What the?? Everything I just wrote DISAPPEARED !!
Please be patient while I rewrite it all.
GEEZ!!! What magic combo of keys did I hit anyway?????


Please see the next post for the missing text.

These photos were not sharpened and did not any have noise removal.

Converted and white balanced in Photo Ninja.
Attached Image: bidens_uvOldBaaderVenus_sun_20110603wf_20192pn.jpg

The only adjustments made to the Raw Composite were a reset of the black point and the white point.
Attached Image: bidens_uvOldBaaderVenus_sun_20110603wf_20192rawComp.jpg

The only adjustments made to the Red Channel photo were a reset of the black point and the white point.
Attached Image: bidens_uvOldBaaderVenus_sun_20110603wf_20192redChan.jpg


Converted and white balanced in Photo Ninja.
Attached Image: bidens_uvBaader_sun_20110603wf_20193origpn.jpg

The only adjustments made to the Raw Composite were a reset of the black point and the white point.
Attached Image: bidens_uvBaader_sun_20110603wf_20193rawComp.jpg

The only adjustments made to the Red Channel photo were a reset of the black point and the white point.
Attached Image: bidens_uvBaader_sun_20110603wf_20193redChan.jpg
Andrea G. Blum
Often found hanging out with flowers & bees.

#2 Andrea B.

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Posted 12 February 2018 - 01:28

MISSING WRITE-UP

The old Baader VenusU was mentioned in another topic causing me to remember that I had made this test back in 2011 using my old D300. The D300 had no internal filter so it was easy enough to open it up and pop in the small 1.25" Baader VenusU to make this test.

The photos here are noisy and not so great, but they do serve to show that the old VenusU was a leaky little filter!! I'm wondering whether there might have been some Visible light leak in addition to the obvious IR wash-out of the classic UV-bullseye in the center of the little Bidens flower?

These photos were made outdoors in Sunlight with no boost from artificial UV illumination such as from a UV-Led or a UV-flash. It is possible that extra UV could help the old VenusU overcome some of its leakage due to the huge amount of IR in sunlight? I will leave that experiment to someone else to try.

These photos were not sharpened and did not any have noise removal.
Andrea G. Blum
Often found hanging out with flowers & bees.

#3 Andrea B.

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Posted 12 February 2018 - 02:09

Gaak. Those fotos are really awful. Oh well. :rolleyes:

I wonder if I still have that VenusU because I need to make a better comparison test! I thought I had saved it, but it is not in the current filter cases.
Andrea G. Blum
Often found hanging out with flowers & bees.