sd Quattro with Kyoei Kuribayashi (ebay Clone) lens

[GaryR]

Trying out a newly aquired Kyoei Kuribayashi (ebay Clone) 35mm lens on my Sigma sd Quattro. Using an Andrea U filter, b&w UV seems to work well in full sun, but I probably should have used a higher ISO for the handheld Dandelion and Marigold shots. Too windy for the Centaurea cyanus (Cornflower), so I decided to try it indoors with Convoy S2 UV ichia flashlight w/UVEX welding Ultrasonic shades. One was taken in Monochrome mode and the other in color w/2500k Manual WB. I ordered a second Convoy, so I can illuminate from two 45° angles. Thoughts, and criticisms welcome.

 

 

 

 

[dabateman]

Great,

When you moved inside what were your exposure values?

Also what was the exposure for the dandelion image?

I have a SD14, and trying to get a hold on if the SDq will be similar, better or worse. However, I may have to rent one to compare head to head. My out door uv levels have been really low lately. Maybe due to the extensive humidity we have in DC area.

[GaryR]

Great, When you moved inside what were your exposure values? Also what was the exposure for the dandelion image? I have a SD14, and trying to get a hold on if the SDq will be similar, better or worse. However, I may have to rent one to compare head to head. My out door uv levels have been really low lately. Maybe due to the extensive humidity we have in DC area.

 

The dandelion and marigold were more of test, so I didn't spend much time on setup. The mystery lens has a standard f-scale ring that clicks into place, with a secondary variable f-stop ring. I moved that ring slightly off f.3.5, so likely in the f/5.6 range. Definitely need a higher ISO on a breezy day.

 

The sd Quattro has a Monochrome mode menu, with a 'Filtering Effect' slider, which allows you select Y, O, R, G, B. The 'B' blue setting is the only setting that works for monochrome UV. As you may have guessed, the 'R' red setting works best for monochrome IR.

 

No exposure data on the indoor (bw and color) versions because I used Super Fine Detail (SFD) mode on the sdQ. SFD takes 7 different exposures, then combines them into a single 300MB .X3I file, apparently resulting in lower noise and higher detail.

 

bw dandelion

1/8 sec; f/5.6? ISO 400

 

bw marigold

0.3 sec; f/5.6? ISO 400

 

cornflower bw and color

SFD mode, f/22

[OlDoinyo]

It appears that the background bokeh is negative on this lens. I can't make out what the foreground looks like. I am impressed with the ability to hand-hold (I have never been able to hand-hold UV except with film.)

 

The B setting probably isolates the sensor's uppermost layer, so that it is the only setting that works is no surprise.

[Andrea B.]

The flowers look good, Gary.

I also have two Convoys and had the same thought you mentioned about aiming them at 45º angles. But how are you setting up your Convoys? Do you have flashlight holders or clamps or what? So far I have been propping mine on stacks of books. This is not ideal. :D

[GaryR]

The flowers look good, Gary.

I also have two Convoys and had the same thought you mentioned about aiming them at 45º angles. But how are you setting up your Convoys? Do you have flashlight holders or clamps or what? So far I have been propping mine on stacks of books. This is not ideal. :D

 

I did this handheld, while tripping the shutter. The sdQ has a delay timer, so I still might be able to handhold 2 Convoys. Portable clamps sound like the best solution, and will have to look into that.

[Andrea B.]

You know those mini Gorillapods? Flexible, ball-jointed. I wonder if there's a way to attach a small flashlight to that kind of thing?

 

Added: Just was lookiing and those Gorillapods are not particularly inexpensive!

[Cadmium]

Gary, as far as your photos, the Nichia LED is going to give a fairly monochrome shot because it has a pretty narrow 360nm band of light.

If wanted, you would get a lot more 'false UV color' by using a common compact fluorescent black light.

[Andy Perrin]

Gary, as far as your photos, the Nichia LED is going to give a fairly monochrome shot because it has a pretty narrow 360nm band of light.

If wanted, you would get a lot more 'false UV color' by using a common compact fluorescent black light.

Since his body is one of the Foveon X3 sensors, and they put all the UV in one channel (if I read the other thread correctly?) then he is not going to get false color regardless. There is no Bayer.

[GaryR]

You know those mini Gorillapods? Flexible, ball-jointed. I wonder if there's a way to attach a small flashlight to that kind of thing?

 

Added: Just was lookiing and those Gorillapods are not particularly inexpensive!

 

The Convoy with battery has some weight, and not sure if a small tripod would be enough to hold it in place.

 

My first thought was a bullet-cam clamp, then remembered that I already have a bunch of inexpensive Nylon cable clamps. The nylon was too small, but the larger metal cable clamp (with rubber sleeve) fit the Convoy, with a bit of bending. Bolting the flashlight clamp to rigid or telescoping antenna or rod, with table clamp could be assembled from hardware parts. Here are a few shots of the Convoy with the metal cable clamp attached.

 

 

[Andrea B.]

That's what I'm talkin' about ! Nice solution for the flashlight wrap and shouldn't be too difficult to go from that to tripod.

 

I was looking at a gorillapod which would hold 6 pounds. Figured I could use it for a few different things besides holding UV-Led flashlights for fluorescence work. I haven't completely decided yet.

[Cadmium]

Microphone holders

[Cadmium]

Hmm, thought I made a comment on here about using a black light instead of Nichia LED to get more UV color? No? Well maybe it was removed also?

Maybe a different topic? I thought it was in this topic...

Anyway, if you want the UV shots to have more color, a common compact fluorescent black light should give a wider UV spectrum of light than the narrow 365nm spectrum of the Nichia torches (Convoy...MTE...),

which are great for fluorescence photography, but not much good for UV unless you only want a monochrome 365nm shot.

[Andrea B.]

Cadmium, your comment is above in Post #8.

But again, as Andy has mentioned, false color variation is not possible with a Foveon sensor because UV records only in the blue channel. :)

---

 

EDITOR'S NOTE: The discussion about lens clones which was in this photographic topic has been split off and moved to its own thread found here: http://www.ultravioletphotography.com/content/index.php/topic/2795-about-lens-clones/

[dabateman]

I don't know if the monochrome mode does fully throw away all the information from the two lower read parts of the sensor. But it may based on how clean those images look at 400 ISO.

However, your in color final image clearly shows that you are either getting noise from lower levels or that some uv is creeping down.

 

What would be ideal is if you download the 30 day trial of Raw digger and look at the Raw channels to see if there is anything in colour mode and in the monochrome mode with your uv filters and uv lights.

 

I may do the same once I work out every thing I want to test.

 

[Andrea B.]

I can always run a few photos through Raw Digger for you if you like.

Just put the raws into Dropbox or some equivalent and PM me the URL. ;)

[GaryR]

It appears that the background bokeh is negative on this lens. I can't make out what the foreground looks like. I am impressed with the ability to hand-hold (I have never been able to hand-hold UV except with film.) The B setting probably isolates the sensor's uppermost layer, so that it is the only setting that works is no surprise.

 

The grass background on the dandelion shot is about 2" away from the focal point, and does create a distracting bokeh with this lens.

 

Yes, that's true about the 'B' setting for monochrome UV, as it's the only color filter, that doesn't result in a black frame. By contrast the monochrome 'R' setting (and to a lesser degree, Y, O), is the only one that works with an on-lens 720nm IR filter.

[GaryR]

Since his body is one of the Foveon X3 sensors, and they put all the UV in one channel (if I read the other thread correctly?) then he is not going to get false color regardless. There is no Bayer.

 

That's correct...no color on the sdQ foveon sensor.

[GaryR]

Hmm, thought I made a comment on here about using a black light instead of Nichia LED to get more UV color? No? Well maybe it was removed also? Maybe a different topic? I thought it was in this topic... Anyway, if you want the UV shots to have more color, a common compact fluorescent black light should give a wider UV spectrum of light than the narrow 365nm spectrum of the Nichia torches (Convoy...MTE...), which are great for fluorescence photography, but not much good for UV unless you only want a monochrome 365nm shot.

 

I can confirm that the sdQ doesn't work for color UV, using either an on-lens UV filter (Andrea U) or illuminating the subject directly with a Convoy S2+. I've tried the Convoy, with and without a UV/IR-block filter installed, and the results are always the same...blue to magenta images. My low power blacklight produces a bit more magenta, but no other colors on the sdQ. By contrast, my unconverted Olympus M1, produced a nice range of UV/VF colors using only Convoy illumination. I think I might go for a higher output 365nm flashlight for the M1, and continue to use the sdQ for BW UV.

[GaryR]

I don't know if the monochrome mode does fully throw away all the information from the two lower read parts of the sensor. But it may based on how clean those images look at 400 ISO.

However, your in color final image clearly shows that you are either getting noise from lower levels or that some uv is creeping down.

 

What would be ideal is if you download the 30 day trial of Raw digger and look at the Raw channels to see if there is anything in colour mode and in the monochrome mode with your uv filters and uv lights.

 

I may do the same once I work out every thing I want to test.

 

Using either an Andrea U filter, or Convoy flashlight, in Monochrome mode, the 'G' setting appears very underexposed in LV, the 'R' setting is black, but the 'B' displays everything in full detail and tone. All of the color WB settings, record only blue to magenta hues, with no other color information. My Olympus M1 can record a full range of Fluorescence colors using the Convoy. For mono UV, IR and full spectrum, the sdQ will still be my first choice.

[OlDoinyo]

Are you using the camera's X3F files, or JPEG as output? I found when I had an SD14 that the firmware did very strange things with UV or IR filters; sometimes there was hardly any image at all in the X3F file but the JPEG file from the same exposure looked normal. (I know that makes no sense, but I saw what I saw....)

[GaryR]

Are you using the camera's X3F files, or JPEG as output? I found when I had an SD14 that the firmware did very strange things with UV or IR filters; sometimes there was hardly any image at all in the X3F file but the JPEG file from the same exposure looked normal. (I know that makes no sense, but I saw what I saw....)

I have the sdQ set to RAW+jpeg. The jpegs on my FS-DP1 were often perfect SOOC, but I find that full spectrum jpegs on the sdQ are nowhere near as good, as a well-processed X3F. Normal visible light, images are great on the sdQ, but once you remove the dust protector, weird and wonderful results follow. Although UV and IR filters don't work well in color mode, they do work extremely well in the sdQ Monochrome mode. sdQ Monochrome jpeg's look the same as the X3F.

[dabateman]

On the SD14, I find that White balance is critical. If you don't get a good WB, then strange colors appear, that cannot be easily fixed later.

Thank you for the update Gary. Sound like all the uv is in the top highres layer. Also sounds like all the IR is in the lower, low res layer. That is good news. As I find the SD14 to be an IR camera and sometimes tricky to avoid IR leakage.

Seems like that is not a big problem with the SDQ. Also explains why IR images haven't been that great comming out of the Quantro sensor.

 

For editing X3F files I now like the revived Photivo:

https://photivo.bouchier.be/en/pages/Download.html

 

It uses x3f tools and is free.

[colinbm]

Hi Gary

It is good that you are on here with UVP & doing well with the Sigma SDQ.

The magenta that I used to get with my Sigma Foveon cameras, I found that it is from overexposure....reduce the exposure & it goes....?

Did I say I hate magenta....ha ha

It must be remembered with the Foveon sensor, even with the 'dust protector' come IR cut filter removed, the sensor still has a glass ?? cover & the first blue layer is below a thin layer of silicon that will attenuate the UV, but with enough exposure enough UV will get through to get a mono UV image.

 

I'll have to get some of my kit out & get some photography happening again soon.

Cheers

Col

[GaryR]

Hi Gary

It is good that you are on here with UVP & doing well with the Sigma SDQ.

The magenta that I used to get with my Sigma Foveon cameras, I found that it is from overexposure....reduce the exposure & it goes....?

Did I say I hate magenta....ha ha

It must be remembered with the Foveon sensor, even with the 'dust protector' come IR cut filter removed, the sensor still has a glass ?? cover & the first blue layer is below a thin layer of silicon that will attenuate the UV, but with enough exposure enough UV will get through to get a mono UV image.

 

I'll have to get some of my kit out & get some photography happening again soon.

Cheers

Col

 

Hey Colin! Good to hear from you!

I've had the sdQ for a few months now, and finding that the sensor has quite a different response than any other Sigma I've owned. BW IR works great, FS color only works using a Hoya X1 green filter, and UV is restricted to monochrome. Hopefully, the SFD (super fine detail) mode, will produce some interesting results.

 

One thing I've noticed is that the sdQ looks hilarious with a tiny 75mm El-Nikkor lens mounted to the body!

All the Best! -Gary