Pinhole Ultraviolet Transmission Lens Test

Learning Ultraviolet Photography is proving to be such a challenge it reminds me of when I first picked up a camera. How wonderful to be able to shoot 35 photos and not find a single keeper. Reminds me of the film days. I’m finding that trying to imagine how an image will appear, when the focus is using non visible light, has many variables that can affect the outcome.

One of course is the light source. If you don’t have full sun cover, using a dedicated light for a specific bandwidth or a full spectrum flash is essential. Next is choosing quality filters that absorb all light not wanted to affect the image. Also, I’m finding that the lens choice is just as important as the light source itself. Very few lenses are truly dedicated UV lenses made from quartz rather than glass, so the challenge is finding “accidental” lenses that permit good UV transmission.

Below is a basic test I used to determine which of my older lenses would permit the best UV transmission in the 360-365nm bandwidth. I used a pinhole cover with a dedicated Hoya U360 and BG40 filter stack to eliminate all light in the visible and IR range. I used a white plastic as the background and focused a dedicated 365nm light on it. White balance was done on the background. Exposure time was 15 sec and iso 1600. All phtos were post processed with the same settings.

All lenses tested were set to f4 and the rear of the lens was set at 2 1/2 inches from the background. Lenses tested were the Lensbaby Sweet 35 and Edge 80 optics, the Lensbaby Twist 60 and Selective Focus optics, an El-Nikkor 50/4 and Meyer Optik Domiplan 50/2.8 and Helios 44M 58/2. The Domiplan is supposed to transmit down to 345nm from other test located on ultravioletphotography.com (great reference site). The El-Nikkor is also supposed to be a good transmitter. The clearer the light through the lens itself signifies better UV transmission, purple signifies the worst.

From my basic, non-scientific test I was suprised to see the Lensbaby Soft Focus optic seems to perform as well as the Domiplan and both the Lensbaby and Zeniton 35mm lenses performed well. The Zeniton 135 performed poorly, even though it is the same optical construction (4 element / 4 groups) as the Zeniton 35.

Test are as follows:

Lensbaby Sweet 35 and Edge 80 optics

Ultraviolet transmission test, Pinhole Optic, LensBaby, Sweet 35 optic, Edge 80 optic, Hoya U360 filter, 365nm light, UltraViolet, UltraViolet Photography, 365nm Photography, BG40 filter, Bishop CA

Lensbaby Twist 60 and Soft Focus optics

Ultraviolet transmission test, Pinhole Optic, LensBaby, Twist 60 optic, Soft Focus optic, Hoya U360 filter, 365nm light, UltraViolet, UltraViolet Photography, 365nm Photography, BG40 filter, Bishop CA

El-Nikkor 50/4 and Domiplan 50/2.8

Ultraviolet transmission test, Pinhole Optic, LensBaby, El-Nikkor 50/4, Meyer Optic Domiplan 50/2.8, Hoya U360 filter, 365nm light, UltraViolet, UltraViolet Photography, 365nm Photography, BG40 filter, Bishop CA

Zeniton 35/3.5 and 135/3.5

Helios 44M 58/2

Ultraviolet transmission test, Pinhole Optic, LensBaby, Helios 44M 58/2, Hoya U360 filter, 365nm light, UltraViolet, UltraViolet Photography, 365nm Photography, BG40 filter, Bishop CA

Pentax K1 testing Old Glass

Received the new Pentax K1 and decided to run a few test with the older vintage lenses I still have.

Nothing special with the images and minimal post processing, just to show the clarity. Have been pleasantly surprised with the results. I’ll list the lens below each shot posted for reference.

Kiron 28-105 2.8 (respectively), some vignetting at 28 and a little purple fringing. Still very sharp for its age. Shot at f8.

Tokina 70-210 4.5-5.6 (respectively), Slight purple fringing at 210, sharper than my current Sigma 70-200 2.8 APO DG. Shot at f8

Tamron SP90 Macro 1:1, very sharp. Shot at f8

yale lockset macro

Tokina 70-210 4.5-5.6 @210 with +10 Diopter, shot at f8. Some purple fringing with no hood but pleasantly surprised.

inyo register macro

 

Monochrome toning in Lightroom

LightRoom adjustments for Monochrome Photography

Working more with the monochrome techniques we learned at the Shooting the West photography symposium I mentioned in an earlier post. In the past, I would always start in PS to make the majority of my adjustments and then switch over to LR to finalize any highlight/shadow – white/black adjustments and luminosity smoothing before final sharpening. Mark had us start in LR using the hue sliders under color/hsl to determine how we wanted to see that color tone in greyscale. Then we would set everything back to default and make the adjustments using the color sliders under B&W mix. This technique allows the photographer to adjust the photo as if they were using multiple color filter on camera in the field. Continue reading

Bodie Ghost Town- Bower 8mm Fisheye lens Review

A few weeks back I was able to test out the Bower 8mm fisheye lens designed with the APS sensor in mind.

The model I tried was labeled Bower, though there are many other names on the same lens produced by Samyang/Rokinon.
Supposedly an all manual lens I found the Pentax version functioned in both A & ATV priority as well.
The exposure settings on the lens seemed to be true to my camera, about 1/3 less needed in post. I only tried f5.6 & 8, as most reviews I’d read mentioned sharpness dropping off after f11.
The Bower 8mm fisheye lens instructions suggest focusing in live view. I didn’t find this helpful and found the focusing ring the best option. Other reviews mention having to calibrate the focusing ring to infinity for the model/brand camera you own. I found this to be the correct. At 1.5 feet it seemed accurate but noticed the ring would go past infinity on the scale and would be a bit out of focus.

Monochrome - Fisheye - lens - Bower - 8mm - Bower 8mm fisheye lens - Bodie - BodieStatePark - GhostTownPhotography

The price is about 2/3’s less than the Pentax 10-17mm I rented a few years back and I would say the image quality of the Bower is as good. Also, I think there is less distortion than with the Pentax.
If you find yourself needing a fisheye for a project, I would consider renting a Bower 8mm fisheye/wide-angle lens. For the price they seem to be a  quality lens.
More images taken with the Bower 8mm fisheye lens may be seen in archives/ghosttowns.

Best lenses for night photography

I just read a great article by David Kingham about the best lenses to use for night photography.
Photographing at night doesn’t requires high-end lenses and usually the most basic lenses will perform quite well, especially with a DSLR.

The author points out one of the most important features of a lens for night photography is the amount of light your lens will let in, providing you with the best options of a lower ISO to reduce noise. He mentions this is one advantage of primes over zooms. Primes having a fixed focal length usually offer a wider aperture, though he does offer some nice zoom options for those of us who use both. Continue reading