Common lawn flowers

[Cadmium]

Common lawn flowers, Dandelion and English Daisies in UV

 

[Andrea B.]

Very nice photos, Cadmium.

I love the fuzzy stems of the English Daisies.

Maybe you would like to made a botanical entry for your English Daisies if you also have a visible photo? I'll help format it, if you would like to do that.

 

The photos are very sharp. What lens were you using? Just curious.

[Cadmium]

Thanks Andrea. I actually wasn't impressed personally with the sharpness of these. This was using the UV-Nikkor, and I have done some in the past with the Kuri that were sharper.

I do like the backed off distance using the 105mm however. La La U for those.

So I will need to do a direct comparison between the UV-Nikkor and the Kuribayashi 35mm to resolve in my mind which is sharper.

[nfoto]

I do have a number of Kyoei 35/3.5 and allies and they are very clearly less sharp than the UV-Nikkor.

[JMC]

I think they they look really sharp Steve. And they're really nice photos too - I love seeing these common flowers in UV.

[Cadmium]

Some stack test comparisons. Was a little windy, as usual, the slightest amount of movement with longer exposures and you loose sharpness. Shot at ISO 200.

I usually refuse to shoot with higher ISO, so I just shoot the pic over and over, but still I get some motion wind blur.

 

Hoya U-340 8mm

 

Schott UG5 (Hoya U-330) 1mm + S8612 2mm (UV+Blue+Green+Red, 'Bird-Vision'?), not much difference here, but if you have red flowers in the photo also, they will be red, using 1.5mm red will be black.

 

Schott UG5 (Hoya U-330) 1.5mm + S8612 2mm (UV+Blue+Green, the standard 'Bee-Vision' stack)

 

Hard to come by Schott BG24A 5mm + S8612 2mm (UV+Blue+Green+Red), use S8612 1mm and you get more red than brown.

 

Visual

[Andy Perrin]

What was the blue background in the visible shot? They all look nice to me!

[Stefano]

That 8 mm thick Hoya U-340 filter is becoming more and more interesting, and I think it is also making you more and more interested in it. It is quite thick for a filter, but has unique features. Do you still think that you will not sell it as a product?

[Cadmium]

Schott BG24A is equivalent to Russian filter ПС11.

 

Stefano, I don't have any U-340 that thick now, I use to, just the ones I have for myself.

 

Andy, That is the Baader UV/IR-Cut. I don't like that filter for visible, personally, I prefer BG38 or BG40, because they deliver a more nature white balance using my cameras,

but the Baader UV/IR-Cut was in my bag and the BG38/BG40 was not. Andrea wanted a visual reference, so I used this one.

The back ground is just moss and dandelion leaves and other things, shot in the shade.

I think the blue in that visual pic is just some sky reflection.

[Stefano]

One day, when I will have a better camera/lens system, I want to try that filter. You need a capable lens to really gain from this filter.

[colinbm]

Thanks Steve, I like this one a lot...."Hard to come by Schott BG24A 5mm + S8612 2mm (UV+Blue+Green+Red),"

[Cadmium]

Believe it or not, this is the very same flower, it grows in a hollowed out pumice rock, so I don't get it mixed up with other dandelions.

The first shot above is shot earlier in the day, the flower is not yet fully opened, the second shot below is shot later in the day after the flower is fully expanded,

and notice the center of each flower shot, see how things are even seemingly structurally different, almost as if it is a different flower.

These two shots were taken on the same day, I think about about 5 hours apart.

 

Once again, Schott BG24A 5mm + S8612 2mm (UV+Blue+Green+Red).

[Ninjin]

I really like your pictures, especially the first one!

 

 

I wanted to show my one, I think the flower is called Heliopsis, but I'm not sure. So said the owner of the flower. It was already late sunset when I found it.

In UV this flower always looks like 'painted petals with crazy brush'. It turns out a different color - on the one petal.

Here is an option for ПС11.

 

 

Visible, Hoya330_1.5 mm S8612_2 mm, ПС11_5 mm S8612_2 mm.

[Ninjin]

Probably there was more sun in the second picture of dandelion (difference in red)?

 

Here are some of my ПС11 filter options with bright sunshine.

Color is very dependent there on the thickness of the glass and the sun - I never know what color I will get with it.

[colinbm]

Interesting colours Ninjin, such a variation with the different thicknesses....

[Cadmium]

Evgeniya, Nice examples! Thank you.

I am not sure I white balanced the same as you. I will try some more later.

Theoretically, it should work approximately the same ad BG3, but BG3 cuts off more of the red.

[Cadmium]

Evgeniya, I also like the Heliopsis set, very interesting blotchy pattern in the U-330 shot especially, and ПС11 shot also.

[dabateman]

Great images Cadmium!

 

You are inspiring me to look at my BG12 again. I have that in 1.5, 3 and 5mm from an old microscope. Its different but close.

 

[Cadmium]

Dave, not even close. BG12 has no red, where as BG24A has more red than BG3, BG25, etc....

BG24A is not like any of those, because it has more red.

Grab some BG24A if you can find some, because it won't be around forever. I suggest getting 2mm and 3mm thicknesses, then you can stack for 5mm when wanted.

 

[ulf]

UG2A is also an an interesting alternative for these UV-VIS filter combinations if someone is able to produce 0.7mm thin filters.

 

With an UV-starved illumination the UG2A 1mm is showing promising results together with S8612, 2mm.

With more UV the coloured UV-signatures becomes much too dark, in the same way as produced by a UG5, 2mm stack

[Ninjin]

Thank you Cadmium!

 

I also tried Wratten 47, on your advice 1.5 mm for the 'red centers'. Very nice for me - It looks similar!

 

The whole red flower - I could not get. This does not allow to increase the thickness to 3 mm. Because - the flower comes in full green, not red. (I can’t find my test at 3 mm, so maybe later.)

 

Wratten#47_1,5mm + S8612_1 mm.

[Cadmium]

Wow, that is very nice, interesting! I don't remember suggesting that. I will try it, but I don't know where my #47 is at.

Did you use Gel or glass?

[dabateman]

My Parks 38A has an almost IRchrome red look.

If I can find a good image I will share. Your #47 +S8612 reminded me of that filter.

[Cadmium]

UG2A is also an an interesting alternative for these UV-VIS filter combinations if someone is able to produce 0.7mm thin filters.

 

With an UV-starved illumination the UG2A 1mm is showing promising results together with S8612, 2mm.

With more UV the coloured UV-signatures becomes much too dark, in the same way as produced by a UG5, 2mm stack

 

Ha ha, Ulf, persistent... but as I have told you, 0.7mm is too thin for me.

Try ITOS for 0.7mm thick.

 

What are you thinking of stacking the 0.7mm with? S8612 2mm?

[ulf]

I'm glad that I can make you laugh in these gloom times.

 

I have handled big, much thinner glass sheets for special optical purposes.

Thickness 0.1mm, outer Ø130mm, center hole Ø25mm. We had 30-40 of those and I must admit that I cracked some of them.

I still have a few smaller ones, Ø55mm, without any center holes.

 

That makes a Ø52mm, 0.7mm glass disc look rather robust. It is not that far from 1mm thickness.

 

With the right methods and equipment it is not an impossible goal to make 0.7mm filter glass.

Even if your current manufacturing process makes it difficult to get a good yield with thin filter glass, it might be that the processes could be expanded or improved.

If you are interested in discussing possible ideas for making such filters please message me privately.

 

Both thicker than normal and thinner than normal filter glass open up for interesting filter responses!

 

Gutta cavat lapidem, non vi, sed saepe cadendo.