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Flowers in sunshine with ZB2 and s8612

Filters Multispectral
28 replies to this topic

#1 Yon Marsh

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Posted 25 April 2021 - 22:31

In sunshine with EL-nikkor 80mm and 1.5mm ZB2 and 2mm S8612 stacked filters. Nikon D800 full spectrum.

The Marsh Marigold , Caltha palustris was shot against water which here has a magenta cast on the water, the other shots are common daisies, Bellis perennis with a dandelion, Taraxacum officinale, then a white dead-nettle, Lamium album.

Not sure if the backgrounds are too blue, or what one would expect with this combination. First time I’ve experimented with this. Tried initially doing a white balance as per a UV only image- looked wrong, so then white balanced off a grey scale instead as if in normal light. The ZB2 is meant to be something similar to a BG3?
Its almost an Yves Klein blue.


Caltha palustris
Attached Image: yon-Marsh-UV-_8036681_1.JPG

Bellis perennis with Taraxacum officinale
Attached Image: yon-Marsh-UV-_8036710_1.JPG

Lamium album.
Attached Image: yon-Marsh-UV-_8036713_1.JPG

Edited by Yon Marsh, 25 April 2021 - 22:47.


#2 Andy Perrin

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Posted 25 April 2021 - 23:43

It looks very blue! I played around in PhotoNinja with one of them and came up with this (I forget what I clicked!):
Attached Image: post-204-0-71589800-1619389955n.jpg

I bet doing it with RAW would yield much better results.

Edited by Andy Perrin, 25 April 2021 - 23:44.


#3 Stefano

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Posted 26 April 2021 - 00:30

Maybe they should look a bit like these?

#4 Yon Marsh

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Posted 26 April 2021 - 08:11

Thanks Andy and Stefano, I'm using ACR with raw files and DNG profile editor, I didnt quite know which way to put down a baseline calibration for this, not used photoninja or have it yet. Will see what I can come up with now I know which way it should swing towards.

#5 Cadmium

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Posted 26 April 2021 - 10:07

That is what I use, Photo Ninja, for white balance, plus sometimes Photoshop's Auto Levels.
I think you can still get a free trial copy of Photo Ninja. I think it is the best all around program for white balance.

#6 Andrea B.

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Posted 26 April 2021 - 20:42

For a filter like the ZB2 it is necessary to photograph the subject together with some kind of white standard which is stable under both UV and Visible and Infrared light. Then you white balance against the white standard and save the results to use again on a photo of the subject not containing the white standard.

I don't seem to be able to find an actual example using a filter like the ZB2.

Here is an example using some sunflowers.
Attached Image: sunflr_vis_crop.jpg

I photographed the sunflowers with the Sony A7R using a UV-pass filter which also passes a bit of blue. As noted, this is not like a ZB2, but it will illustrate the process, OK? The lens that day was a CZJ 60/4.5 Objectiv.

The sunflowers and a Spectralon white standard in their raw colors (from Raw Digger) show what was recorded prior to setting any kind of white balance.
If the browser is wide enough, these will appear side-by-side.
Attached Image: sunflr_uvAndBlue_rawComp_crop.jpgAttached Image: std_uvAndBlue_rawComp_crop.jpg

This is how the photos would look in daylight white balance. There is a strong blue cast. However, I rather like the sunflowers with this blue cast.
Attached Image: sunflr_uvAndBlue_daylight_crop.jpgAttached Image: std_uvAndBlue_daylight_crop.jpg

Here is how the photos look after the white balance made on the standard was then applied to the flower photo.
Attached Image: sunflr_uvAndBlue_wb_crop.jpgAttached Image: std_uvAndBlue_wb_crop.jpg



We only white balance against a stable white standard for standardization of documentary photos. You certainly can use other whte balance approaches for artistic purposes. :grin:

I want to note here that many members have found that ACR does not properly white balance their UV photos. I cannot speak to that myself as I gave up Photoshop a long time ago. I am not sure whether ACR has improved recently or not.

P.S. These examples are not completely finished because I just wanted to demonstrate the process quickly. I was using Photo Ninja as a converter and white balancer.
Andrea G. Blum
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#7 Andrea B.

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Posted 26 April 2021 - 23:16

another P.S. Your results clearly show that the ZB2 Stack as a UV + Blue (lots of blue) filter is recording something in UV because both the Marsh Marigold and the Dandelion show their UV signature. Elsewhere we had made some speculations that perhaps the visible violet and blue light would "wash out" the UV. That appears not to happen - at least with these two flowers.

I am beginning to think that maybe white balance against a standard for the ZB2 Stack will produce very odd results. It may turn out that you won't want to WB your photos !! Interesting.
Andrea G. Blum
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#8 Andy Perrin

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Posted 26 April 2021 - 23:27

View PostAndrea B., on 26 April 2021 - 23:16, said:

another P.S. Your results clearly show that the ZB2 Stack as a UV + Blue (lots of blue) filter is recording something in UV because both the Marsh Marigold and the Dandelion show their UV signature. Elsewhere we had made some speculations that perhaps the visible violet and blue light would "wash out" the UV. That appears not to happen - at least with these two flowers.
A caveat: It obviously depends a lot on the exact spectra of the filter. This was not the filter I was referring to when I made that comment! I don't think any *universal* remark that holds for every filter can even be made about when UV washes out the visible, but it must happen at SOME point for SOME filters.

Edited by Andy Perrin, 26 April 2021 - 23:29.


#9 dabateman

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Posted 27 April 2021 - 03:45

I have a ZB1 filter which is similar to the ZB2, but with much less IR. When white balance, grass goes a very nice orange. But a dandelion flowers will still have a dark pattern.

#10 Yon Marsh

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Posted 27 April 2021 - 06:41

Thank you for the dialogue and tips. Ive managed to download a trial of photoninja but not had time to use it yet.
I have made a reference white balance "card" for UV out of some sheet aluminium with two 2mm deep PTFE discs on it, one white and one grey which at the moment I include in a shot to calibrate later as everything is shot in raw. ( No glue is used to secure discs, they are screwed on as if glued they coud have false readings from luminescence).

Here it is when used with U-360+S8612.
Attached Image: UV-White balance for UVa Yon Marsh.jpg
No damage was done to the tree positioning the scale as the tree was dead.


Here is the same card when used on the ZB2 + s8612 without any modifications. I under expose for the sceen so the readings off the "card" dont blow out when processing and have some info in them.
Attached Image: UV-WB-yon-Marsh_8036731.jpg

I had a bit of a dabble yesterday in DNG profile editor and ACR, the blue from this filter with the s8612 is insane.

I now realise I forgot to menton it was combined initially with the s8612 as I was not interested in the IR bit of information for this idea, really sorry; I was keen to post and completely forgot about that, :-(,

Thank you

Edited by Yon Marsh, 27 April 2021 - 06:51.


#11 UlfW

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Posted 27 April 2021 - 10:15

ZB2 is the Chinese variant of BG3.
I have never tried it, but my BG3 2mm demands a rather big adjustment if white balancing fully, against PTFE.
I often prefer the results with the average of the entire image instead as that gives more pleasing overall colours.

It would be interesting to see how a 1.5mm filter would work compared to the 2mm thick one I have.
Ulf Wilhelmson
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#12 UlfW

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Posted 27 April 2021 - 10:18

Try the FastRawViwer. It has a free trial period and work rather well with extreme WBs.
https://www.fastrawviewer.com/
Ulf Wilhelmson
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#13 Yon Marsh

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Posted 30 April 2021 - 17:17

Thanks, Photo Ninja seems great, but I'm unable to fully use it due to Apple.
I've just tried FastRawViewer (FRV) which seems to give the same results and white balance results as Photo Ninja but I am having issues and missing something when trying to use FRV with photoshop. If I go from FRV to pass (open) it in photoshop it then opens up camera raw, nothing in FRV previously corrected carries through. Photo Ninja could export the corrected file as a TIFF which one can work on, how can I do the same from FRV?
Guess its darn simple and staring me in my face but its not clicked with me yet.
Any help or suggestions ref FRV and a workflow to get the image out.
Thank you.

#14 Andy Perrin

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Posted 30 April 2021 - 19:16

Why is Apple a problem for PN? I’m on a Mac and have no issues?

#15 Yon Marsh

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Posted 30 April 2021 - 19:47

It's to do with computer giants forcing obsolescence into their hardware and software (adobe), along with a triggered Y2K issue triggering on march 19th and reserved coded bits in photo ninja.
Photo Ninja is all up and running, trial keys may not work to test things out.
Photo Ninja seems a good easy to use programme, certainly makes the processors work, but for me it's just apple's forced obsolescence.

#16 Andy Perrin

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Posted 30 April 2021 - 21:09

You should just contact PhotoNinja, they are very responsive to emails. I’m sure they would know if Apple is making their products unusable and have a workaround for you. As I said, it’s not an issue for me and I’m also on a Mac. Although I am using Mojave so it could be different for you. But I would talk to the PN folks. They are very nice.

#17 Yon Marsh

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Posted 01 May 2021 - 08:20

Photo Ninja have been brilliant and very responsive and quick, jolly decent.
This is an issue which now can't be solved for me at this time, no work arounds :-(

Im seeing how I can tackle this in other ways just at the minute.

Edited by Yon Marsh, 01 May 2021 - 08:21.


#18 Yon Marsh

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Posted 01 May 2021 - 10:10

I meant no work arounds in Photo Ninja just now.
Jim from from Photo Ninja was very helpful, Alex from FastRawViewer was also an immense help. I was hoping that the XMP files from FRV would be ok but the weak link is ACR, its tint/colour temp value stops at 2000k/150 tint whereas FRW can handle 1824K/2118 tint values!

A big thanks to Ulf W, I've managed to sort out a workflow with RawPhotoProcessor64, the resulting tiff files being tarted up in ACR, still have a bit more testing to do, here are the new tests.

Attached Image: yon-Marsh-UV-_8036681_V1c.jpg

Attached Image: yon-Marsh-UV-_8036710_1V1c.jpg

Attached Image: yon-Marsh-UV-_8036713_1V1c.jpg

Edited by Yon Marsh, 01 May 2021 - 10:18.


#19 Stefano

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Posted 01 May 2021 - 12:34

I like these!

#20 colinbm

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Posted 01 May 2021 - 12:47

Looks great, love the colours.