Panasonic Lumix DMC G3 Camera

[colinbm]

Hi Klaus

Yes it is a combined filter.

No processing, just a .jpg from the G3 .RW2 file.

Col

 

Steven Smeed Sparticle Filter Array, with four UV, narrow band pass filters, 340nm, 350nm, 370nm & 386nm, placed in front of the lens.

(This was taken some time ago, with it on my Sigma DP2)

[kds315]

OK, I see. I never shot through that, only took shots of it when backlit

(I have alarge array with many filters that Steve made for me).

That 370nm is a typo I guess, should read 360nm.

[colinbm]

Thanks Klaus for picking up that typo....no the 360 should be 370nm.

I'll have to re-post the photo.

Col

[Andrea B.]

I would love to see the "demosaic only" of that filter shot in post #97.

That is: in Photo Ninja check the Demosaic box only, then save.

Don't check any other boxes.

 

Another interesting version to see would be with only Demosaic and Exposure/Detail checked where As Shot is the only setting under Exposure/Detail with all others set to 0.

 

Do I have this correctly that the false colours are relative to the BaaderU?

[colinbm]

OK Andrea, we have something for you...

Pictures as requested.....

Col

 

Shot as previous in #97...

Opened in PhotoNinja with Demosaic only selected.

 

 

Shot as previous in #97...

Opened in PhotoNinja with Demosaic & Exposure Detail only selected.

[Andrea B.]

Thank you, Col !!! Much appreciated.

 

I had thought that the 386nm should record more of a violet colour. That is, before white balance, it should record more of a violet colour. And indeed it seems to be so.

 

I wonder if I can get that green with a narrowband 340nm on a Nikon? Gotta try that this summer some time.

[colinbm]

Glad it helped Andrea.

[kds315]

Indeed, those colors are closer to what I am used to see (and again Colin, the 370nm should read 360nm; 370nm looks differently)

[colinbm]

Hi Klaus

Just for the record, I took the Sparticle Array apart & checked the filters.....

This is exactly what is written on each ferrule.

340nm 145538. (BP10)

350nm BP 10 340 0430.

MGPD 370BP20 36654.

386.5NB2 135687.

Cheers

Col

[JCDowdy]

Col,

I see that the bandpass on your filter set varies. The 350 is 10, the 370 is 20, the 386.5 is 2. What is the BP on the 340?

 

Klaus,

Is that perhaps why the colors are not exactly what you are used to seeing?

[enricosavazzi]

Thank you, Col !!! Much appreciated.

 

I had thought that the 386nm should record more of a violet colour. That is, before white balance, it should record more of a violet colour. And indeed it seems to be so.

 

I wonder if I can get that green with a narrowband 340nm on a Nikon? Gotta try that this summer some time.

I am sure you can. At least on all converted cameras I tried, wavelengths between 320 and 340 nm are recorded as green. However, if the filter transmits also longer wavelengths (around 350-360 nm) the (false) yellow/orange of these wavelengths will overwhelm the green and make it undetectable.

[colinbm]

Thanks John & Enrico

Unfortunately, my records of these filters elude me for now, however, I have found a previous discussion I had here with this same Sparticle Array........different camera (Sigma Foveon).

http://www.ultraviol...__hl__sparticle

Unfortunately, eBay has removed the link to the 340nm filter, but the other three are still there.

Thankfully, in the above post I had the 340nm filter as being BP10.

Col

[colinbm]

Hi everyone

I am still working with the Panasonic G3.

I have now added some quartz to replace the internal glass removed in the conversion.

I have placed a 3mm quartz in the recess that the 3mm filters were removed from & I placed a 1mm quartz in the place of the shaker glass, but it is static.

I can now get infinity focus, with all lenses on their respective adapters.

This week I purchased a 20mm f3.5 Olympus PEN F lens, hoping it would be as good as on this graph....(PS, it is the same)

http://www.ultraviol...0mm-25mm-pen-f/

But it was just as Alex had experienced here....

http://www.ultraviol...capable-lenses/

20mm "Pen-F bayonet mount for old APS film camera, not new Oly digital Pens. Very sharp in UV, except for outermost image corners. Susceptible to flare. Transmission limited to approx. 370-400nm. Photo Link (scroll down)."

I have tested it in photos & with my UV Sparticle Array & on my Black-Ray J221 radiometer, it failed to impress me & is limited in UV as Alex has found.

I will look for another wide angle lens for UV photography in a month or two.

I was looking forwards to using the PenF 20mm lens, as it is very wide & is close focusing at 0.2mm (8"), maybe the PenF25mm is a better performer in UV ??

Cheers

Col

[Alex H]

Colin, it is still one of the best ≈20mm lenses I've tested in UV.

[colinbm]

Thanks Alex

About the Pen F 20mm.....

As I said, it, "is limited in UV as Alex has found."

I will still be pursuing its attributes as I stated, "it is very wide & is close focusing at 0.2mm (8")".

Col

[kds315]

Thanks Alex

About the Pen F 20mm.....

As I said, it, "is limited in UV as Alex has found."

I will still be pursuing its attributes as I stated, "it is very wide & is close focusing at 0.2mm (8")".

Col

 

You crack me up Colin: "failed to impress me" - which other 20mm focal length lenses have you ever had in hand that performs like that one?

[Andrea B.]

I don't have any 20s. Too wide. :)

[colinbm]

You crack me up Colin: "failed to impress me" - which other 20mm focal length lenses have you ever had in hand that performs like that one?

 

I am sorry Klaus, but I have made a grave error reading your graph of the PenF 20mm lens.

Looking at the graph in 'full size', I can see that I mistook the 350 line as 300nm, my bad mistake!

It is not a case of 'what other 20mm lens works as well for UV photography', it is a case of this one NOT being very capable..........

My interpretation of my copy of this lens (PenF 20mm f3.5), is it preforms more like this your graph (below).......my estimation, overlaid on your graph, is in magenta...... (now removed)

Cheers

Col

 

Enlarged part of graph from this post.....

http://www.ultraviol...0mm-25mm-pen-f/

[Alex H]

I am glad you figured it out, Colin. I have tested few lenses in 20-25mm range, and picked this one not only because of its transmission (no so much for its transmission), but also for sharpness and field of view.

[Andrea B.]

Alex, what other 20-25s might you have that would be of interest in the Lens Sticky?

 

***

 

As a general comment, I think we all tend to over-emphasize "how deep" a lens might go into the UV. If we can get reasonably good transmission between 350-400 nm, then we can make some very satisfying UV photographs with a broadband UV-pass filter.

[Alex H]

Andrea, I have already posted about the lenses I consider useful for UV photography in the past. Nothing new to add.

[colinbm]

Here we go....if the PenF 20mm f3.5 is considered, 'usable', for UV photography, then perhaps the G3's kit lens is 'usable' for UV too ?

Cheers

Col

 

[Alex H]

So how deep do you think it transmits?

[colinbm]

Thanks Alex

Well, the PenF 20mm f3.5, just lit up the 350nm BP10 filter on my, Stephen Smeed Sparticle UV Filter Array, but, the kit G3 14-45mm lens, didn't light up the 350nm BP10 filter.

But, the 370nm BP20nm was lit the same. From comparing photos, I would say they are very close, sure, the PenF 20mm is only slightly better at transmitting UV, but the G3 kit 14-45mm lens is much more versatile & functions fully with the camera.

Cheers

Col

 

PS, I would say that the G3 kit 14-45mm lens, would only take off a pencil line from the 350nm side.

 

Graph supplied by our favorite filter supplier :)

[Alex H]

I had 16mm kit lent for NEX cameras - it did transmit UV probably as much (or close to) the 20/3.5 Pen F/FT lens, was wider and was controlled by the camera. But the image quality was not as good, especially in the corners.

 

If 14-45mm lens works well for you than great.