Flower Composite series

[dabateman]

My flower seemed to be stimulated by the UV light. But I thought I too would try the UV color composite test.

 

Here is my series, I am using Full spectrum Olympus EM1 camera. The Pentax UAT 85mm lens at F11. I am using a ExoTerra UVB light bulb on the left, a Lucky Herb UVB bulb on the right and a 302nm bulb in front of the tiny flower.

 

Visible of flower:

 

303bp10 with 330WB80 filter:

 

313bp25 with 330WB80 filter:

 

335bp10 with Baader Venus U filter:

 

370bp15 with Baader Venus U Filter:

 

390bp25 filter

 

Baader Venus U filter only:

 

330WB80 Filter only:

 

Now the fun part. These were aligned using Bernards method with the command prompt and then color composite in Gimp. These are my favorite with Blue as 390nm and 370nm as Green:

 

Red channel 335, Green 370, Blue 390nm

 

Red 313, Green 370, Blue 390nm

 

This is the typical range that I don't really like the output of

 

Blue 335nm, Green 370nm, Red 390nm:

[bvf]

Nice. What's the flower? Looks daisy-ish to me, without actually being a daisy. (I expect Birna will be along soon to put me right.)

 

I'm a bit puzzled when trying to interpret the images. The last one (using the RGB allocation that I do) gives the petals a slightly reddish colour, indicating that the petals aren't reflecting much UV but that what there is is mainly at longer wavelengths. But the penultimate image shows quite strong red colouring, indicating the predominant reflection is at the shorter wavelength end.

[Andy Perrin]

I would white balance the final images so they don't have such a strong color cast. The point is to see the variations, so if one color is dominating, you don't get to see them. If I try it at home, white balancing off the cup, the second to last one (Red 313, Green 370, Blue 390nm) has a nice range of reds and blues in it.

[dabateman]

Well I took all the short cuts on these images. I first resized to 1024x768 in Infran viewer from the out of camera Jpegs. Then I ran them through the alignment code that Bernard provided. Yes I know this is bad, but the files are tinny and ran quick and easy to work with. Also if you just download the images I provided here, you will be working with the exact same starting files.

 

Next time I will do the following:

1. Open Raw files in Raw Therapee, adjust to taste and output .Tif files.

2. Run the alignment code

3. Open the stack in Gimp and play with the order.

4. See if I can output .Tif from Gimp. May need to update.

5. Final adjustments in other software.

 

 

The flower was opening up under UV, and projecting out more shoots (Stama?) while imaging. So there is difference just due to time. See this:

 

Visible at start:

 

Visible at end:

 

However,

I do like this technique, I see difference between the bandpass filters that I don't see in the direct images. This helps to really see the stronger reflections.

[Cadmium]

David, Those composites are very interesting! :-)

[nfoto]

The flower certainly belongs to the Daisy Family (Asteraceae), which however is the largest of all plant families with nearly 25,000 known species. My guess is Erigeron annuus, a quite widespread weed in Europe. Do not take this identification as anything other than approximate.

[ulf]

Daisies have a very long flowering period.

I still see them popping up now in lawns, even after having had several frost nights.

The first ones I noticed was in early April, when starting looking for flowers.

Can they be of the same species?

[nfoto]

Probably not the same species as depicted in this thread. The small flowers in the lawns in all likelihood are Bellis perennis. That species can flower almost around the entire year, conditions permitting.

[dabateman]

Bellis perennis, looks huge in comparison.

This flower was smaller than my pinky finger nail.

[ulf]

Probably not the same species as depicted in this thread. The small flowers in the lawns in all likelihood are Bellis perennis. That species can flower almost around the entire year, conditions permitting.

Thanks for the good answer to my badly phrased question.

I wondered about the ones I have seen, not David's tiny flower.

[Andrea B.]

Concur with Birna -- that is a very typical Erigeron. We have many (over 90!!) in the US. Further ID would require knowledge of the hairiness of the stems and the shape of the leaves. Likely possibilities are E. annuus and its very similar cousin E. strigosus. The E. pulchellus in the East usually has a pinkish tinge and is larger than this. The E. philadelphicus in the Eastern US has finer, narrower rays than this.

 

If you look at the stems and most of the hairs are pointing upwards very close to the stem, then E. strigosus. If the hairs are mostly relaxed and leaning away from the stems, then E. annuus.

 

Dave, your pinky finger nail is quite probably larger than mine. So I'm guessing you think the flower is about 1/2" across?

 

Given that the leaves appear to be large-ish near the top of the flower, I will also go with E. annuus, but only as a tentative ID.