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

What’s the fuss about lens quality reviews

(Recently submitted post to PentaxForums.)

I find it curious how we photographers fret so much over lens quality reviews or lens superiority AND I do understand the difference between precision engineered glass and a soda bottle.

It’s easy to blur/fade an image made from a lens transmitting great IQ but impossible to add detail from an optic that never saw it in the first place.

I was using PF long before I became a member (I know, my bad) because of the wonderful amount of knowledge shared here by fellow Pentaxians. The lens database is incredible, especially the coverage of vintage and third party lenses.

My ex girlfriend shoots Canon and doing a fair amount of research there, it seems nearly impossible to find any reviews on anything other than the “latest & greatest” (and never so much information in one place.) I sense PF members seem more concerned with sharing creative process than promoting Market Hype.

I curb myself as much as possible from LBA but do like to keep informed on lens performance (vintage and modern), especially the diversified hands on experience I find here. Reading a recent post on Lenses and the K-1, I was very pleased with a response by Noel Porter. “One of the key things with any lens is understanding it’s characteristics and using it’s strengths or avoiding it’s weak areas (soft corners wide open etc).” (Read more at: http://www.pentaxforums.com/forums/190-pentax-k-1/329374-my-k-1-wasted-my-legacy-glass.html#ixzz4JuFQw1zm)

I’ve always viewed lenses as paint brushes. An artist may use two different brushes of the same size or shape to achieve different desired effects.

My main workhorse lens is a Sigma 24-60/2.8, it provides consistently good IQ. It will never provide the color and smoothness of my M50/1.7, the sharpness of my A50/2.8 macro or dirty/gritty film feel of my Vivitar 35/2.8. The Sigma 70-200/2.8 DG OS USM is in no way superior to my old F300/4.5 for IQ, but is the “go-to” lens during low light, nighttime sports events (and yet it never finds itself in the vest pocket like the tak-f 70-200 on a day hike.) They each are what they are.

Still, one of my favorite techniques is – NO LENS PHOTOGRAPHY (IQ be damned) – images below.

Zone Plate on K3

Black Locust Blooms, backyard photography, garden photography, plant photography, fine art, zone plate

http://www.instructables.com/id/PHOTOGRAPHY%3A-Creating-Perfect-Pinholes-and-Zonepla/

http://www.whizkidtech.redprince.net/zoneplate/

Writing with light – The brush doesn’t make the painting, the painting dictates the brush.

I’m consistently impressed while reading an inquiry here on the forums, how often a responding member will ask for more information on someones shooting style, subject matter, etc. before giving a recommendation. Sometimes it’s the newest technology when appropriate but often members encourage us to explore the strong characteristics of what we might already have or can easily obtain.

I look forward to reading more “fretting” over lenses, you folks make it an enjoyable treat and me happy to be a member of PF.

Another Zone Plate

Laws - California - locomotive - slim princess - railroads - museums - zone plate - black&white - monochrome - Bishop

Not much to write about this month, Just enjoying the Pentax K-1

Spending time this month reading about lenses and the Pentax K-1.

I find Pentax Forums a very nice resource for all sorts of material, lenses, cameras, flash, techniques – and not necessarily related to solely Pentax.
Easy to research articles and always someone willing to give a helpful reply.
Shots taken this month with the Pentax K-1 and various lenses or optics.

Death Valley by Zone Plates

Last month I was fortunate enough to get out of the snow and head to Death Valley for a well enjoyed photography trip.

For the past couple of years I have really been enjoying working with zone plates and decided to try my luck in the desert landscape.
Zone plates are very similar to pinhole photography in there is no lens and the resulting photo is from light diffraction rather than refraction through a glass element.
Zone plates however use a pattern of opaque and solid concentric circles resulting in a softer (less sharp) image caused by a larger amount of undiffracted light to reach the image plane. They are often reduced in contrast and produce a distinct glow or halo in the highlights.
California - Death Valley - National Parks - Panamint - historic locations - valley - zone plate photography Continue reading

Zone Plate Photography on US Route 6

One of the cool things about where I live is the distinction of the western terminus of Historic US Route 6.

The route starts in Provincetown MA and follows a cross country track to become the second longest highway in the United States.
Originally the western terminus was in Long Beach CA and in 1937 it was the longest highway in America with a total of 3652 miles.

California - ranch - tatum ranch - barn - horse - monochrome - historic highways - us route 6 - zone plate photography- Bishop Continue reading

Back to the Basics 2 – zone plate photography

I’ve really been enjoying working with the zone plate photography and the fresnel effect it gives

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There is something challenging about not being able to picture the image through a viewfinder and trying to imagine how the final will emerge. Continue reading

Back to the Basics – Pinhole & Zone Plate Photography

Pinhole & Zone Plate Photography. Back to the Basics – No Lens, No Meter, No Viewfinder

A couple of weekends ago I was fortunate enough to partake in a day trip down Titus Canyon in Death Valley. A colleague was wanting to work on some landscapes for the upcoming “Shooting the West” photo symposium and as I had always wanted to see this canyon and the en-lying ghost town of Leadfield, off we went.
Also around this time I had been studying the effects of pinhole photography. For the price of a lens cap I was able to pick up a pinhole/zoneplate optic for my Lensbaby to give it a try. I hadn’t really done any pinhole since college and never tried anything like zone plate photography, so was curious to see the effects and try the skills myself.
The pinhole is around an f177, so there is not enough light passing through to frame anything in the viewfinder and of course no in camera metering. While the zone plate is an f19 because of the concentric circles, the same applies. Continue reading