14 replies to this topic

[Andrea B.]

Purpose of Test: To verify that each lens can shoot at a close distance in Vis/IR/UV and can record in those wavelengths. Each lens was given the extension needed to work within a foot of the flower. I did not attempt to match the perspective/distance across the photos in this simple test.

Subject: Rudbeckia hirta [Black-eyed Susan]
Location: My Front Yard, Middletown, New Jersey, USA
Date: 14 September 2014
Camera: Nikon D600-broadband
Raw Converter: Photo Ninja
TIFF to JPG Converter: Photo Mechanic

Visible White Balance: D600 Profile made from Color Checker Passport in Photo Ninja.
IR White Balance: Photo Ninja Color Correction droopper dragged over photo diagonal.
UV White Balance: D600 UV Profiles made with Labsphere Reflective Standards in Photo Ninja. These profiles are combined with the Visible D600-Profile and adjusted slightly using the rock vase in the photos which has proven to be UV-neutral. Use of a standard at time of shooting permits tiny adjustments for time-of-day and changing light conditions not otherwise accounted for in the initial global profile.

Target: Each lens was focused on the front edge of the central cone of the Rudbeckia. Deviations from this are mentioned as they arise. Focus was reset through Live View after each focus change.

Editing: The photos were edited in Photo Ninja as though I were going to post them in UVP's botanical section with the exception that I did not apply any local edits such as selective sharpening or clone-outs of unwanted dusties. Typical edits include small exposure adjustments, highlight control, opening shadows slightly, minor saturation pullbacks to bring the red channel under control.
Also the photos are uncropped so that any center/edge differences could be noted. Unlike the companion F-mount Infinity test, very few center/edge differences were seen in this test.

UV-capability: The sunlight and clouds varied a bit during the shoot, so please do not read too much into the shooting times. All the lenses tested are apparently capable of recording the Rudbeckia's UV-signature. In comparison to the speeds in the companion F-mount Infinity test, speeds are much longer because the work is closer, and the lenses must be placed on extension tubes or helicoids.
At f/11 and ISO 400 the UV speeds are:

UV-Planar 60/4.0 = 3"
Omegar 75/4.5 = 3"
EL-Nikkor 80/5.6 = 4"
UV-Nikkor 105/4.5 + PN11= 1/2.5"
UV-Nikkor 105/4.5, unextended = 1/2.5"
Lentar 135/3.5 = 3"

Of the F-mount 35s, the Noflexars are faster in UV. No surprise as they have been long known to be good for UV since Klaus Schmitt's early tests. The Noflexar comparative speeds in the Vis/IR/UV shots vary slightly only due to changing light conditions.
Noflexar-1 35/3.5 = 1.6"
Noflexar-2 35/3.5 = 1.6"
Soligor 35/3.5 = 2.5"
Vivitar 35/3.5 = 3"

Lens: Zeiss UV-Planar 60mm f/4.0
This industrial lens was not used in the companion F-mount Infinity test because I have not been able to determine its flange focal distance. Although presented first here, this was actually the last series shot in the test. The light was at more of an angle and shadows were long.
Mount: M39.
Adapter: M39/M42.
Adapter/Helicoid: M42/F.
FFD: ?

Visible Light [f/11 for 1/125" @ ISO 100 in Sunlight with Baader UVIR-Block Filter]


Infrared Light [f/11 for 1/50" @ ISO 100 in Sunlight with B+W 093 IR-Pass Filter]


Ultraviolet Light [f/11 for 3" @ ISO 400 in Sunlight with Baader UV-Pass Filter]



Lens: Rodenstock Omegar 75mm f/4.5
Mount: M39.
Adapter: M39/M42.
Adapter/Helicoid: M42/F.
FFD: approximately 60nm.
Front Filter Size: The front of the lens has no filter threads, so filters were held in place while shooting.

Visible Light [f/11 for 1/160" @ ISO 100 in Sunlight with Baader UVIR-Block Filter]


Infrared Light [f/11 for 1/30" @ ISO 100 in Sunlight with B+W 093 IR-Pass Filter]


Ultraviolet Light [f/11 for 3" @ ISO 400 in Sunlight with Baader UV-Pass Filter]



Lens: EL-Nikkor 80mm f/5.6
This is the newer style EL-Nikkor enlarging lens which has an aperture window. I have not made a permanent modification to the lens to prevent light leaks.
Unlike its performance in the companion F-mount Infinity test, the EL-Nikkor showed no light leaks in the close work while I covered its aperture window with my hand.
Do note for the record that focusing the EL-Nikkor at its widest f/5.6 aperture is not easy even in good sunlight.
Mount: M39.
Adapter: M39/M42.
Adapter/Helicoid: M42/F.
FFD: 70mm.
Front Filter Size: 40.5mm

Visible Light [f/11 for 1/50" @ ISO 100 in Sunlight with Baader UVIR-Block Filter]


Infrared Light [f/11 for 1/15" @ ISO 100 in Sunlight with B+W 093 IR-Pass Filter]


Ultraviolet Light [f/11 for 4" @ ISO 400 in Sunlight with Baader UV-Pass Filter]



Lens: Nikon UV-Nikkor 105mm f/4.5 + Extension Tube PN-11
This is the first series with the UV-Nikkor. I ran a second series without the PN-11 just for grins. Of course, using an extension tube caused depth of field to suffer a bit.
Mount: Nikon F.
FFD: 46.50mm.
Front Filter Size: 52mm.

Visible Light [f/11 for 1/400" @ ISO 100 in Sunlight with Baader UVIR-Block Filter]


Infrared Light [f/11 for 1/125" @ ISO 100 in Sunlight with B+W 093 IR-Pass Filter]


Ultraviolet Light [f/11 for 1/2.5" @ ISO 400 in Sunlight with Baader UV-Pass Filter]



Lens: Nikon UV-Nikkor 105mm f/4.5, Unextended
This is the second series with the UV-Nikkor. This time no extension tube was added.
Mount: Nikon F.
FFD: 46.50mm.
Front Filter Size: 52mm.

Visible Light [f/11 for 1/400" @ ISO 100 in Sunlight with Baader UVIR-Block Filter]


Infrared Light [f/11 for 1/200" @ ISO 100 in Sunlight with B+W 093 IR-Pass Filter]


Ultraviolet Light [f/11 for 1/2.5" @ ISO 400 in Sunlight with Baader UV-Pass Filter]



Lens: Lentar 135mm f/3.5
The Lentar was extended with a focusing helicoid.
When using the Lentar, I had some difficulty placing the tripod at the correct distance for focusing in the different wavelengths. So the IR focus was on the back edge of the Rudbeckia cone, not the front edge as in other photos. And the UV focus was a little forward of the front edge of the Rudbeckia cone.
Mount: T2.
Adapter: Fotodiox T2/F. (Not used in this particular test.)
FFD: 55mm.
Front Filter Size: 49mm.

Visible Light [f/11 for 1/80" @ ISO 100 in Sunlight with Baader UVIR-Block Filter]


Infrared Light [f/11 for 1/135" @ ISO 100 in Sunlight with B+W 093 IR-Pass Filter]


Ultraviolet Light [f/11 for 3" @ ISO 400 in Sunlight with Baader UV-Pass Filter]

[Andrea B.]

Lens: Novoflex Noflexar 35mm f/3.5 #1
The Noflexar has an unusual 3-staged pull-out to permit shooting at close distances.
There is a cyan streak on the left side of the UV photo indicative of a light leak possibly along the pull-out axis or from the adapted mount. It happens intermittently. I must pursue this further to determine the cause.
Mount: Permanently adapted to Nikon F-mount. Original mount unknown.
FFD: 46.50mm.
Front Filter Size: 49mm.

Visible Light [f/11 for 1/200" @ ISO 100 in Sunlight with Baader UVIR-Block Filter]


Infrared Light [f/11 for 1/100" @ ISO 100 in Sunlight with B+W 093 IR-Pass Filter]


Ultraviolet Light [f/11 for 1.6" @ ISO 400 in Sunlight with Baader UV-Pass Filter]


Lens: Novoflex Noflexar 35mm f/3.5 #2
The Noflexar has an unusual 3-staged pull-out to permit shooting at close distances.
Mount: Nikon F.
FFD: 46.50mm.
Front Filter Size: 49mm

Visible Light [f/11 for 1/200" @ ISO 100 in Sunlight with Baader UVIR-Block Filter]


Infrared Light [f/11 for 1/60" @ ISO 100 in Sunlight with B+W 093 IR-Pass Filter]


Ultraviolet Light [f/11 for 1.6" @ ISO 400 in Sunlight with Baader UV-Pass Filter]


Lens: Soligor Wide 35mm f/3.5
The Soligor was extended with a focusing helicoid.
Mount: T2.
Adapter: Fotodiox T2/F. (Not used in this particular test.)
FFD: 55mm.
Front Filter Size: 43mm.

Visible Light [f/11 for 1/200" @ ISO 100 in Sunlight with Baader UVIR-Block Filter]


Infrared Light [f/3.5 for 1/500" @ ISO 100 in Sunlight with B+W 093 IR-Pass Filter]
I failed to stop down to f/11 after focusing at f/3.5.


Ultraviolet Light [f/11 for 2.5" @ ISO 400 in Sunlight with Baader UV-Pass Filter]



Lens: Vivitar 35mm f/3.5
The Vivitar was extended with a focusing helicoid.
The green grass in the background of the UV photograph is a mystery. I have no idea what has caused this patchy false colour. It is possible that it is a center/edge phenomena as was seen in many of the UV photos in the companion F-mount Infinity series. I will try an alternate conversion to see if I can bring it under control.
Mount: T2.
Adapter: Fotodiox T2/F. (Not used in this particular test.)
FFD: 55mm.
Front Filter Size: 43mm.

Visible Light [f/11 for 1/160" @ ISO 100 in Sunlight with Baader UVIR-Block Filter]


Infrared Light [f/11 for 1/50" @ ISO 100 in Sunlight with B+W 093 IR-Pass Filter]


Ultraviolet Light [f/11 for 3" @ ISO 400 in Sunlight with Baader UV-Pass Filter]

[igoriginal]

Outstanding work, right there! Thank you, Andrea!

[Andrea B.]

Thx, Igor.

*****

I am raising a temporary red flag on the above results. I need to try a reshoot with that UV-Nikkor to verify that the speeds listed above (repeated here) are valid. It would appear that the UV-Nikkor is about 3 stops faster in close work than the other 'long' lenses. Can that be correct?
Hmmm......

UV-Planar 60/4.0 = 3"
Omegar 75/4.5 = 3"
EL-Nikkor 80/5.6 = 4"
UV-Nikkor 105/4.5 + PN11= 1/2.5" ?????
UV-Nikkor 105/4.5 = 1/2.5" ?????
Lentar 135/3.5 = 3"

*****

I've added a few minor updates to the report.

[nfoto]

I'd say the UV-Nikkor is faster than most other lenses for pure UV exposures. The amount will vary depending on the spectral properties of the illumination and the subject of course, but 1-2 EV is entirely feasible, perhaps more.

[igoriginal]

If the UV-Nikkor has higher transmission curves (or "peaks") and / or transmits deeper than many other lenses, then of course this should translate to less exposure time.

Which is something I proposed (in another discussion), that deeper-transmitting lenses CAN be more useful, even if in UV-floral work, because of reduced exposure times.

Thus, why, even if confined to doing only UV-floral work with non-dedicated ("accidental") lenses ... it is preferable to have a lens that transmits down to 320 nm, instead of a lens that transmits only down to 365 nm. If those are the only "affordable" options that one has to choose between.

Edited by igoriginal, 18 September 2014 - 19:11.

[Andrea B.]

I'd say the UV-Nikkor is faster than most other lenses for pure UV exposures. The amount will vary depending on the spectral properties of the illumination and the subject of course, but 1-2 EV is entirely feasible, perhaps more.

Certainly true for close work. The UV-Nikkor didn't lead by much in the landscape series.
However, I was not expecting a 3-stop difference in the close work !!

[Andrea B.]

Those UV-Nikkor times are good accurate.
Wow.

[JCDowdy]

Why is the UV-Planar so long?

[Andrea B.]

The UV-Planar is an enlarger type lens which requires a helicoid.
Any lens placed on an extension tube or extended by an added helicoid will see less light at the image plane. So you must set either a longer speed or a wider aperture than you would for the same shot made without extension.

The UV-Planar has around 60-70% UV transmission (if I'm remembering correctly) and is made from special glass. It is very sharp.

[JCDowdy]

I see, now I understand why it had shutter speeds similar to the other enlargers.
I was mistakenly thinking it was a quartz/fluorite.

[enricosavazzi]

A couple of questions, just to make sure.
Is the Baader U filter mounted in a blackened metal cell? (e.g. the original Baader mount)
Did you attach the Baader U to the front of the lenses with a light-tight adapter with all lenses in this test, or did you hand-hold the filter in front of some of these lenses?

[Andrea B.]

I was mistakenly thinking it was a quartz/fluorite.
It is. I should have elaborated.

This is from Klaus Schmitt's database about the UV-Planar.
Mod. double Gauss 5 elements in 5 groups. Made of CaF2, LiF2 and special UV transmitting glass.
CaF₂ = calcium fluoride. In mineral form this is called fluorite.
I think Klaus may have meant to write LiF for lithium fluoride because lithium has only one valence electron.
Here is a link about using LiF for optics: http://www.crystran....um-fluoride-lif

***********************************

Enrico:
Yes, the Baader U filter is mounted in its original filter ring. I've added a 48-52mm step ring to attach the filter to all lenses which themselves have the necessary step ring to match the 52mm - except for the Rodenstock Omegar 75/4.5 which has no filter threads. For the Omegar only I had to hand-hold the filters in front of the lens. This is so noted in the Omegar write-up.

[JCDowdy]

Andrea B., on 20 September 2014 - 14:59, said:

This is from Klaus Schmitt's database about the UV-Planar.
Mod. double Gauss 5 elements in 5 groups. Made of CaF2, LiF2 and special UV transmitting glass.

Seems odd to combine such exotic materials with a special UV transmitting glass which seems, according to Dr. Schmitt's data significantly limits transmittance. Looks like a UV-B cut-off with ~50% transmssion at ~320 nm. Perhaps it is to protect the relatively soft CaF₂ and LiF elements?

[enricosavazzi]

Correcting optical aberrations requires optical elements made with at least two (and usually more) types of glass of different refraction index, dispersion etc. One of the problems of designing a UV lens is that few types of glass transmit UV sufficiently well, and therefore there aren't many types of glass with different optical properties to choose from. The most common are quartz and fluorite. Other materials transmit UV well but are generally not used to make optical elements because their other optical properties are not especially advantageous. We often see lithium fluoride, magnesium fluoride, sapphire etc. in flat optical windows, but not in lenses.

I believe that the CoastalOpt 60 mm was designed with one element made of a type of glass that does not transmit UV too well, in addition to a few fluorite and quartz elements, in order to correct aberrations with a reasonably low number of elements and to prevent the size, weight and cost of the lens from spiralling out of control.

Edited by enricosavazzi, 20 September 2014 - 20:55.