Mirabilis jalapa [Marvel of Peru]

[photoni]

Castellani, Antonio (2022) Mirabilis jalapa L. (Nyctaginaceae) Marvel of Peru. Photographs made in visible, ultraviolet and mixed light. LINK

 

Other Common Names:

• Four O'clock Flower
• Bella di Notte in Italian, Beautiful at Night
• Don Diego de Noche in Spanish

 

Reference:  Wikipedia Mirabilis jalapa

 

 

 

For the last two photos a white balance made with Teflon and daylight was used.

Is the green of the leaves a mistake? or a 340 nm signal?

Thanks, Antonio

 

Sony A7 f.s. Soligor 35mm, Elinchrome flashlight, 32> 1500w clear quartz tube

 

 

Nemo 365 nm light  -  different white balance

.

 

.

 

 

[colinbm]

Very colourful Toni

[KhanhDam]

All these filters but my eye is drawn to the filtered one.  Nice job

[Nate]

Excellent comparisons, quite a few favorites in there. I have seen some green leaves look greenish in UV too with a BaaderU filter. I'm curious about this too.

[photoni]

17 hours ago, Nate said:

I have seen some green leaves look greenish in UV too with a BaaderU filter. I'm curious about this too.

@Nate me too !

I don't understand if the green of the leaves of the last two is a balancing error or what ...

 

I double-checked the files and corrected the white balance of some photos (I changed the image above) but not having a neutral reference, they are my interpretations.

[ulf]

1 hour ago, photoni said:

I don't understand if the green of the leaves of the last two is a balancing error or what ...

It is strange, but there might be a few possible answers.

The lens has good UV-reach and the camera, I think, also has a reasonable UV-reach.

 

If the flash has a very strong UV-output this actually might be reflected light from the false greenish 340nm band.

Some leafs and petals has cells at the surface that reflect light before it reaches the UV-dark chlorophyll. 

However the TSN according to published transmission graphs block deeper UV-a rather early.

 

I have not measured the TSN-filter and do not know how good the actual UV-transmission and IR-suppression is, compared to the S8612 or BG39, 2mm.

If the TSN allows some IR leakage that might also be what you see.

What thickness do your TSN, ZWB1 and ZWB2 have?

[photoni]

On 9/5/2022 at 11:48 AM, ulf said:

If the TSN allows some IR leakage that might also be what you see.

 

my test with the diffraction grating say almost zero

 

.

On 9/5/2022 at 11:48 AM, ulf said:

What thickness do your TSN, ZWB1 and ZWB2 have?

 

all are about 2mm thick
the only two with a thickness of 1.5 is QB39 in this test I put it single and double.

 

.

I took the test again. with the same set I added flowers and basil leaves,

and for a reference I added an anodized aluminum "bonsai" wire with teflon tape cap.
I have found that aluminum is much better because it is not overexposed like Teflon.

 

.

.

these are the last two photos (previous) with a correct white balance.

.

 

 

what fooled me was the neutral gray color of the wall and the color of the Ikea pitcher

 

.

[ulf]

Problem solved!

None of my suggestions were valid. 

 

It was the WB al along.

Assuming that a background is UV-neutral is always risky!

Well done solving the problem yourself Tony!

[Nate]

Great job figuring it out.

I question my WB technique sometimes with my plumbers tape card. I don't know how much to expose when making the WB calibration shot. If I under expose the color on the card, I get different false colors than with a longer exposure.

[Yves W]

Thank you Antonio, how much time spent, it is beautiful and interesting.

Ok with Ulf, the TSN575 cuts a little the UV 

[Andy Perrin]

Nate, possibly putting the plumbers tape card at an angle to the camera to reduce the chance of overexposure is an idea? I think if your WB is changing with longer exposure, it is saturating.

[Nate]

Thanks @Andy PerrinI'll give that a try

[Adrian]

Mirabilis is a well known example of having fluorescent pollen, presumably to attract pollinators after dark, when lit by moonlight.

[nfoto]

Indeed, M. jalapa has large pollen grains with interesting UVIVF appearance.

 

(an old image, sorry about bad quality)

 

[Andy Perrin]

The quality is fine, although your latest images are certainly better. At least at iphone screen size!

 

(If I zoom in, I see how grainy it is, but it’s decent when small.)

[photoni]

5 hours ago, nfoto said:

Indeed, M. jalapa has large pollen grains with interesting UVIVF appearance.

yours is fantastic, superlative!

I looked at mine (with light green filter) with 100% crop is beautiful!

[nfoto]

My picture was taken 17 years ago. So lots of digital progress have occurred since then.

 

Magnification around 5X if I recall correctly.

[Doug A]

Excellent series @photoni. You always capture remarkable colors with all the filter combinations. Love the 5X UVIVF @nfoto.

Thanks for sharing,

Doug A

[photoni]

9 hours ago, nfoto said:

My picture was taken 17 years ago. So lots of digital progress have occurred since then.

 

Magnification around 5X if I recall correctly.

 

@nfoto what camera did you use? I looked at the EXIF there is no data ... not even © !!!
if I view your photo at 95% there is a strange moire of the grain, perhaps the Jpeg compression?

in 2005 I had the D2x, the best camera on the market, but only good at 100-200 iso.

[Andy Perrin]

1 hour ago, photoni said:

 

@nfoto what camera did you use? I looked at the EXIF there is no data ... not even © !!!
if I view your photo at 95% there is a strange moire of the grain, perhaps the Jpeg compression?

 

No, that’s the fixed pattern noise of the sensor itself. The noise must have been very high compared to sensitivity back then. 
 

https://en.m.wikipedia.org/wiki/Fixed-pattern_noise