Seen on Ebay [Thread includes some lens tests.]

[Bill De Jager]

Bill, it was great to hear from you with such a nice newsy post. Reading between the lines, it sounds as though you were not quite well. So I hope that you are feeling lots better now. Do take care of yourself, now, OK?

 

Thanks, I'm feeling far better now. My number one priority this year is staying healthy under the stress and long hours of work I see coming again. Also, sorry for my delayed response. Unfortunately, I was sidelined by a cold just after the UV effort I describe below so I decided to wait until I felt reasonably better, especially in the head.

 

I am particularly eager to see a photo made with your LifePixel UV-conversion.

 

 

Working on it! I took some photos last weekend with the UV-Nikkor, including one of the color checker and the standards. Then I ran into some software issues, then out of time. When the software is squared away (in progress right now) I'll get a couple of photos ready and post them.

 

So last Sunday I spent three hours trying to test my 1000mm f/8 tele-Takumar (with FD mount), which I had hoped might actually be useful for UV astrophotography. It has five elements in five groups and I think it's not multi-coated so there's a chance there. One previous effort had seemingly shown that it would not focus well in UV, but I wanted to try again in better light to make sure. It seems to pass UV reasonably deeply for a non-dedicated lens just going by the color of the results. I had to spend some time familiarizing myself with the Canon, which I've hardly used, and learning the remote control which seemed to be cantankerous. I made lots of goofs along the way; at one point the camera took about 50 photos in a row on its own because I misunderstood the settings.

 

The whole thing was made harder by the fact that the Ed Mika glassless FD to EOS adapter (intended for long lenses with beyond-infinity leeway in the focus mechanism) doesn't quite seem to get the focus out to infinity despite the almost-certain focus shift in UV.

 

So I had the lens on the first floor inside my house, pointed a bit up at some somewhat-distant vegetation, an approach which was tricky due to all the bare trees, shrubs, and wire fences in various possible lines of sight. It turned out that the series of photos I had taken, which I thought was definitive, actually had a very close out-of-focus twig blurred over the entire field of view! This was due to a shift of the entire rig that I made without checking the line of sight except in live view. With this narrow of a field of view and very narrow depth of field it's actually possible to have this happen without it being immediately evident.

 

I also discovered today that the remote release technique I had been using last weekend, with mirror lock-up supposedly activated, didn't actually create a delay after the last mirror activity prior to the shutter release. I need to more carefully research and figure out the interplay of the self-timer, remote, live view, etc. so I can find a way to make sure the mirror goes up and stays up, followed by a suitable delay before the shutter is released. I'd probably be better off using the broadband Sony A6000 with a filter drawer due to the Sony's electronic first curtain and lack of mirror, but I'll have to figure out the adapters to make this work.

 

In any case, I could not get sharp images even just looking at live view. There's a softness issue inherent in the lens which I realize may be connected to the not-quite-secure tube which was subjected to a mount conversion at some time in the past. Off to the shop when I get a chance, and maybe a mount conversion too. This is just too cool of a lens to not try to make it work in some band of light!

 

As Bjørn has observed, you can force UV through almost every lens if the illumination is bright enough and if the exposure is long enough. Given the vast amount of lenses in the world, we have chosen to list UV-capable lenses only. So the assumption is, for now, that any lens which is not listed in the Lens Sticky is probably not as good or useful as a lens which *is* listed in the Lens Sticky. :D

 

I was thinking about just older lenses, with simpler formulas that might seem promising. There's no point in reinventing the wheel over and over, though there is no point in trying to be comprehensive either on negatives.

 

If using your UV-converted camera, you just need to shoot a neutral reflective standard (white or light grey) at the beginning of each shoot under the UV illumination which will be used. The in any editor, perform a white balance step on the white/gray area. Save it as a preset to use on the UV photos from the shoot. This is also useful for setting the tones in a monochrome photo.

 

Photo Ninja is nice if you are using a broadband camera, because Visible colour profiles can be make to restore proper Vis colours which go a bit awry after removal of the internal filters. External UV/IR cut filters do not always restore the original camera colours. Nor is in-camera white balance always enough to restore the original camera colours.

 

Thanks for the advice! I finally used the color checker and standards last weekend.

[Bill De Jager]

That is one pretty lens!

 

Sure is!

 

 

I ran outside today briefly with the lens and my Canon but quickly found the cold bad for my still-unhealthy respiratory tract. Initial and brief impression is that UV transmission is not deep.

[Andrea B.]

Well, Bill, I'm not sure exactly where you are, but the light this time of year in Northern California in the Northern hemisphere may not hold all that much UV? And sunlight never provides all that much UV below 350nm anyway? I think most of what we photograph is between 350-400nm.

 

Sure is a pretty lens though. :D

[Bill De Jager]

Well, Bill, I'm not sure exactly where you are, but the light this time of year in Northern California in the Northern hemisphere may not hold all that much UV? And sunlight never provides all that much UV below 350nm anyway? I think most of what we photograph is between 350-400nm.

 

Sure is a pretty lens though. :D

 

No, there is enough of a difference in UV transmission between lenses to be quite visible even now, a little before the equinox. I'm thinking that the poorer lenses are not transmitting below 370-380 but I have no way of testing that. My latitude is near 38 degrees.

[Bill De Jager]

I am particularly eager to see a photo made with your LifePixel UV-conversion.

 

Well, I got the software set up after some false starts and here is my first effort in Photo Ninja. I used the eyedropper tool to correct the 90% standard to white, but I suspect the colors are still off. It's late so I'll have to look at the tutorials another day. As my parents often jokingly said, "If all else fails, read directions!"

 

http://pic100.picturetrail.com/VOL437/1642984/24174024/410915721.jpg

 

Nikon UV-Nikkor on Canon T3i (600D) with Lifepixel UV conversion and no external filter. Sunlight, somewhat late in the afternoon, 38 degrees north latitude, February 22, 2015. The rag is white in visible light.

[nfoto]

RGB read-out shows the 'UV white' balance isn't entirely perfect, Bill. You should achieve same readings for all channels on your teflon patches, plus the two darkest patches on the CC and its frame all shoulkd appear neutral (albeit with different REGB levels of course). Deviations in R,G,B should be - preferably - within one or two steps off from the average over the three channels.

 

Uneven illumination of the scene might also cause should deviations from a UV-neutral balance, however.

[JCDowdy]

Bill,

Please refresh my memory, what UV filter did Lifepixel implant inside your Canon 600D?

[Bill De Jager]

Thanks, Bjørn! I'll look into it shortly. i also forgot to turn the in-camera WB all the way over like your tutorial states. I left it on auto. :D

 

JC, go to http://www.lifepixel.com/infrared-faq and scroll down to "What kind of filters do you use for conversions?" to see the graph. They don't give any other information. There is a small amount of visible contamination that gets through.

[rfcurry]

BTW, has anyone here had a conversion done by Kolari Vision? http://kolarivision.com/

What results?

Thanks.

[Andrea B.]

Bill, it looks pretty good, although as Bjørn pointed out refinements may be needed.

 

Converting from raw to jpg and from your chosen Photo Ninja color space to sRGB for web posting can - along with resizing - skew colours a tiny bit. So the sample reading should ideally be taken from the editor. Of course for whatever reason the Photo Ninja team has not seen fit yet to give us an RGB dropper to read colours with.

 

With that kind of filter you are seeing some visible violet or blue leak, so the appearance of some green is natural in a white-balanced foto.

 

Let me bring up Photo Ninja and get back to you here with a couple of hints about settings.

 

In this linked thread I show the differences between choices of Light Source in the Color Correction Tool. This is after you use the white dropper to correct colour. There are lots of examples in this thread. There is also one of Bjørn's & my discussions about it all. And a lot of other rambling discussion. All good stuff to help you decide how you want to handle your UV false colour. Just keep in mind that UV colour is false, so there is no right or wrong.

 

http://www.ultraviol...-for-uv-photos/

 

Another illustration of effect of Light Source choice:

http://www.ultraviol...ght-source-tab/

 

This thread shows how to make a color profile in Photo Ninja for visible colour. Such a profile can be applied to UV photos, if desired, after white balancing them.

http://www.ultraviol...e-photos-added/

 

ADDED: Of course I just realized that you cannot profile the Visible colour of your UV-dedicated camera so some of the discussion in the links is inapplicable. However Photo Ninja should have a standard visible colour profile for your camera. The information about choosing a Light Source in the Colour Correct Tool is still relevant.

[Andrea B.]

Reed, yes I have a Kolari conversion of my Pentax K5. It was good. I talked to the Kolari guy a bit via emails to remind him that certain Nikons should not be converted and he was cool about it. Somewhere I have a link. Will try to find. Also Kolari is mentioned in our Sticky as a good conversion shop.

 

Here is a brief discussion with a comment that Kolari made a good conversion:

http://www.fotozones.com/live/index.php/topic/50375-new-conversion-shop-kolari-vision-anyone-tried-them-yet/?hl=kolari

[JCDowdy]

JC, go to http://www.lifepixel.com/infrared-faq and scroll down to "What kind of filters do you use for conversions?" to see the graph. They don't give any other information. There is a small amount of visible contamination that gets through.

 

Not much detail in a linear scale plot. I asked because your photo, judging from the many colors I see on the Passport, appears to show a good deal of visible across a broad spectrum not just a blue leak. It would be interesting to know the OD from 400-700nm.

[Bill De Jager]

Thanks for all the guidance, Andrea. I definitely have some reading up to do. My intent is to generally strive for UV colors very close to the standard that you and Bjørn achieve, basically for the purpose of consistency. I may choose to set color balance differently now and then for photos that don't involve testing, once I get better at it and know what I'm doing. Past attempts at "eye-balling it" did not work well. Frankly, this is an area of digital photography that I just have not paid enough attention to, tending to rely on automated tools.

 

Not much detail in a linear scale plot. I asked because your photo, judging from the many colors I see on the Passport, appears to show a good deal of visible across a broad spectrum not just a blue leak. It would be interesting to know the OD from 400-700nm.

 

Excellent point! I didn't start to appreciate this issue (linear vs. semi-log scale plots of transmission) until I caught up on some recent posts here. Yes, I noticed that the squares looked different than how they usually look on this site when color-balanced. Let's see how the photo looks when I finish the color adjustment. I had hoped this camera would be handy for lenses that take larger filters or none at all, which is why I went for this particular conversion rather than a broadband one.

[colinbm]

I just got a Soligor 28mm f/2.8 Lens M42 mount. Really nice looking & well made lens & extremely well kept.

I haven't found any conclusive details of the lens construction, but it appears to be seven single elements.

Shining the MTE U301 lamp into the lens, there is no clouding or fogging.

On the Blak-Ray J221 365nm radiometer, it is giving #5 out of #60. Not too good ?

I have got this lens in advance of getting a Panasonic G3, so I am hoping that it performs as well as John's post here....

http://www.ultravioletphotography.com/content/index.php/topic/1261-melting-snow-suburban-uv-scape/page__fromsearch__1

Col

[JCDowdy]

Col,

 

I did not use a Soligor in that posting....????

 

There are numerous Soligor 28mm f/2.8 documented, some >20 at last count it seems!

On the other hand, at least one Soligor 28mm f/2.8 is supposed to be OK in UV but I can't tell which, so maybe you will get lucky!

 

However, your meter readings don't sound encouraging.

[colinbm]

Yes I understand it is not the same lens you used in the snow shots. I was just hoping this one was just as good.....

This Soligor 2.8/28mm doesn't seem to be with those others listed either.

The branding on the front ring reads....

SOLIGOR 1:2.8 f=28mm No.1680866 LENS MADE IN JAPAN. M42 mount, min focus 0.45m, filter ring 58mm.

It has a silver aperture ring.

Instead of a Manual/Auto switch, it has another black aperture ring, for previewing.

http://www.ebay.com.au/itm/Soligor-28mm-f-2-8-lens-m42-mount-/131443105189?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2047675.l2557&nma=true&si=55FMxjyiWsFM5yfEJ%252BbZmAc%252Bi2Y%253D&orig_cvip=true&rt=nc

Col

[JCDowdy]

Well, you pay your money and you take your chances!

I might have been more inclined to this one, spin off the bayonet and there is a T-mount underneath.

The one you ordered may also have a t-mount under the M42 from the looks of the photo. If so a T-2 to µ4/3 adapter would be the most solid set-up, otherwise you are stacking adapters.

[colinbm]

Thanks John

I only realised today that these Soligor lenses have T2 threads as well. I didn't think it was that common in photographic lenses.

Yes there is a T2 thread under the M42 mount

Col

[Bill De Jager]

Bill, it looks pretty good, although as Bjørn pointed out refinements may be needed.

 

Converting from raw to jpg and from your chosen Photo Ninja color space to sRGB for web posting can - along with resizing - skew colours a tiny bit. So the sample reading should ideally be taken from the editor. Of course for whatever reason the Photo Ninja team has not seen fit yet to give us an RGB dropper to read colours with.

 

With that kind of filter you are seeing some visible violet or blue leak, so the appearance of some green is natural in a white-balanced foto.

 

Let me bring up Photo Ninja and get back to you here with a couple of hints about settings.

 

In this linked thread I show the differences between choices of Light Source in the Color Correction Tool. This is after you use the white dropper to correct colour. There are lots of examples in this thread. There is also one of Bjørn's & my discussions about it all. And a lot of other rambling discussion. All good stuff to help you decide how you want to handle your UV false colour. Just keep in mind that UV colour is false, so there is no right or wrong.

 

http://www.ultraviol...-for-uv-photos/

 

Another illustration of effect of Light Source choice:

http://www.ultraviol...ght-source-tab/

 

This thread shows how to make a color profile in Photo Ninja for visible colour. Such a profile can be applied to UV photos, if desired, after white balancing them.

http://www.ultraviol...e-photos-added/

 

ADDED: Of course I just realized that you cannot profile the Visible colour of your UV-dedicated camera so some of the discussion in the links is inapplicable. However Photo Ninja should have a standard visible colour profile for your camera. The information about choosing a Light Source in the Colour Correct Tool is still relevant.

 

Well, after some embarrassing false starts*, I took several bracketed series of photos near mid-day today with the following:

 

-Broadband Nikon D5100, UV-Nikkor, and Baader Venus for a reference

-Lifepixel UV-converted Canon 600D, UV-Nikkor, and Baader Venus to remove the visible light leak

-Lifepixel UV-converted Canon 600D, UV-Nikkor, and no filter to see how the visible light leak affects color rendition

 

Unfortunately, I found out afterwards that I could not get the standard site white-balance because I didn't have a custom visible-light profile like in the posts you linked to. I don't have a single photo of the Color Checker and standards in visible light from any camera. I did get some nice purple photos out of Photo Ninja, and the ones from the Canon without the Baader are quite different from the ones with the Baader. When I take care of this gap I'll be able to go back to those RAW files and rework the color balance as you indicated.

 

I also found that I had inadvertently blown out the 99% standard even with the darkest exposures. On top of that, the standards received some reflected light from the Color Checker which I now know is a no-no. I'm not sure how much these issues affect the color balance. Well, next weekend I have some work to do. At least I'm getting good practice, something I have not managed to do in a long time.

 

* So I did the reference photos with the Nikon, then tried the Canon. Nothing visible in live view, no matter what I did! What is going on??? Lens cap off, settings all correct, check again and double check, and still nothing! Finally I realized I'd grabbed my unconverted Canon 70D, a fine camera and much nicer than the 600D, but not capable of seeing significant UV. Duh! Normally I have no trouble telling these two cameras apart.

 

[P.S. PN should be able to get the camera WB profile from the CR2 file, but I think the UV conversion has thrown it for a loop. It lists "no profile" instead of the camera profile. I could try to make one with my Canon 70D as an approximation.]

[Andrea B.]

Bill, it does indeed sound like you are getting some good experience !!

 

It is most def easy to blow that 99% standard out of the water. Your cameras should have some kind of "blinky" warning so you can check that while shooting?? Also temporarily set cams to Spot Metering and use the 99% standard as the spot-upon-which-to-meter. Adjust with EV +/- as needed to bring the histogram to the right but not over.

 

Do you have just the 99% standard? The next one down, 75% I think, is also useful when you've blown the 99% one.

 

Great point about the potential reflection from the CC onto standards. I have the CC and my standards embedded in a foam pelican-like box. I'm hoping that setting everything into the foam prevents reflection, but I'd better run some tests. If not, it is easy enough to simply cover the CC when I'm shooting the standards.

 

Let's see....Photo Ninja....here's a workaround for lack of a 600D visible profile. And a workaround for wb which should bring you reasonably close to the blues.

• On the first 'page' just under the histogram be sure that your 600D is shown in the Profile box. Click on the box and you should get a pop-up window. After selecting 600D at the bottom right see "Built-in" and click that. Then the box will show "Builtin 600D".
  

• Now because you can't profile the 600D visible colour (because it is converted), go to the Color Correction page and select:
  Color correction > Light source > Daylight/Flash
  

• Now do a white balance by selecting the black patch on the CC card. You will see the Mode box change to Manual. That black patch is not perfect for wb, but we've used it in a pinch.
  

 

Everyone I hope is keeping in mind that there is no absolute standardized false colour palette. If you look thru some of the flower work, you can see we drift a bit with blues to blue-violets and yellows to mildly orangish-yellows and so forth. There really would be no way to totally standardize the colours even if we wanted to because of variations in filters, sensors, cameras and lenses. All we are attempting to do is permit some comparisons of floral UV signatures without too much distraction by wildly varying colours.

[Bill De Jager]

Andrea, thanks for the info!

 

I have four standards including the 75% one. I've been using the 2%, 50%, and 99% standards, so I've used the 50% as a reference in Photo Ninja when the 99% was blown out. This last time around I also remembered to set the white balance to tungsten beforehand.

 

I was using massive bracketing but still managed to get it wrong except on one shot where I went one extra stop and reached the sweet spot. Next time I'll do it right and check the histogram.

[Andrea B.]

Yep, the 50% will work too. :D

Maybe try spot metering, check blinkies and then add EV as needed?

[JCDowdy]

Perhaps a little something for our UK members?

 

Looks like it is missing it's T2 to M42 adapter but who really needs that anyway?

[JCDowdy]

I may be the only person that thinks these are worth looking at, but here is another one....

 

Steinheil München Cassar S 2.8/50mm für M42 Schraubanschluss

[rfcurry]

John,

 

I like the Cassar S 50/2.8 as well. IMO, it is definitely a must have for those who can't afford quartz.. Among German 50mm triplets, in my experience the Cassar S surpasses in both UV depth (reaching 320nm?) and build quality, the Meyer-Goerlitz Domiplan 50/2.8, the Ludwig Meritar 50/2.9, and the Ludwig Peronar 50.2.9. I don't know about the Meyer-Goerlitz Trioplan 50/2.8 as I haven't used one of these. [The Trioplan was more expensive than the Domiplan and is now being re-issued -- https://www.meyer-optik-goerlitz.com/en/trioplan-50-f2.9?c=86/ ] I haven't found a Piesker 50 and the Pieskers are always superb.

 

Wide open, none of the triplets has the contrast or image quality of a CZJ Tessar 50/2.8 or the 50/3.5. That one extra piece of glass makes a big difference. But stopped down the Cassar performs very well in UV and seems to go deeper than the Tessar. Also, the performance of the Tessars, assuming all are pre-multi-coating, seems to vary; while I have not heard that or seen that with the Cassars.

 

A fine lens.