I’ve had a chance to try the Raynox 150 recently on both my Pentax M200/4 and my Pentax M100/4 Dental Macro.
The Raynox 150 and 250 are the same optics as the Raynox DCR 1.5 and Raynox DCR 2.5 but come together in a kit with the 52mm mounting plate. These lenses are very well made and are achromatic to deliver nice sharp images without aberrations.
These test results aren’t scientific or even done in a controlled atmosphere. They are just images for you to look at and evaluate to see the quality these lenses can produce.
The Raynox 150 is approximately a 208mm focal length with a diopter strength of 4.8, the 250 is about 125mm and an 8 diopter. Most people choose the higher magnifications of the 250 or 2.5, however with larger magnifications than 1:1 the DOF becomes very thin and the working distance becomes very close. I chose the Raynox 150 mainly for my longer focal length lenses to maintain a greater working distance for more light control while shooting. I bought the kit as I will probably want the 250 for my mid range standard lenses and will post results with those soon.
I’m finding ultraviolet photography to be one of the biggest challenges I’ve come across in the photographic process in years. Such a huge learning curve.
Due to the short bandwidth of ultraviolet light, the reflective transmittance doesn’t seem to travel as far as visible light, plus this also causes a focus shift issue as photographing in infrared does.
With the sensitivity of the converted camera, I have been able to pick up the ultraviolet spectrum at a decent iso (around 800 – 1600 as opposed to 200 – 400) and live view permits achieving a fine focus if I take the time to really review and adjust before I shoot.
More of the problem seems to be in the lenses. Glass, air space and the cement used to join elements in a lens all interfere with the UV transmission. True UV transmission lenses (made with quartz-fluorite elements instead of glass) are still manufactured and a few older ones can be found second hand but these are way beyond my price range at an approximate cost of $3000US and up.
Fortunately ultravioletphotgraphy.com has a list of true and “accidental” lenses for ultraviolet photography work. I managed to pick up one of the Steinheil 50mm Cassarits recently and imediately noticed a difference. While not a spectacular shot, it is the first time I’ve been able to achieve focus on any subject farther away than about six inches.
This was shot midday 1/4 second, f8, iso 1600 using a Hoya U360 and S8612 bringing it to around a 360-365nm light source. The Steinheil triplets have been tested to have a cutoff of around 320nm. I am looking forward to testing this lens (as well as an older Cassarit 100mm) with a Hoya U340 to see if I can achieve a deeper UV cutoff point.
Recently I have begun trying to work with UltraViolet light and my full spectrum K1. I’m enjoying it very much as the learning curve is proving to be a real challenge.
Most of my older lenses (and non of my newer digital) transmit the UV spectrum very well but I’ve been lucky enough to come across a few that are permitting me to do a some hand held shots. I’m finding simpler lenses with fewer elements and cemented groups seem to be working best so far. I’ve picked up a few 4/4 Zenitons and hope to show the results later in the spring during the wildflower season.
Here are a few using an older Lensbaby Soft Focus optic. It is 2 elements in 1 group.
The following are the exposure settings, filters and light source I used while photographing a White Geranium.
All were shot at f5.6 and on a 25mm tube.
1st image is shot with U360 & Kolarivision hotmirror filter stack, FS converted speed-light, iso 800, 1/90th.
2nd with U360/Kolari hotmirror and a dedicated 365nm flashlight, iso 800, 1/45.
3rd with BG3/Kolari hotmirror and dedicated 365nm flashlight, iso 1600, 1/90th.
As I’ve mentioned on my macros page, I’m not a macro photography purist.
I don’t focus on achieving a 1:1 life-size ratio when photographing a subject.
I do prefer using dedicated macro lenses (at least close focus) or macro techniques while doing close focus work as I find there is less distortion than with wide angle lenses.
I also enjoy trying anything that will spur my creativity.
This last winter, I was reading a website on extreme macro photography lens stacking and came across an article about using the Pentax M200/4 as a barrel lens for micro-photograpy work. Extreme-Macro is a fantastic site for studying anything to do with close focus work. There is a wealth of information ranging from techniques to lenses, lighting or magnification calculations.
The page I stumbled upon mentioned the Pentax M200/4 as a wonderful lens to couple with a microscope objective for extreme work.
As I have an old M200 that doesn’t get used in this digital age, I decided to pull it out and see what I might be able to do with what I already had on hand or at least low cost investment.
A 52mm-52mm coupling ring, a 52mm-40.5mm step-down ring (which I did have to buy) and my old Rodagon 105/5.6 enlarging lens reverse mounted.
I must admit here that I am often lazy about using a tripod unless doing night shots and still prefer using an optical viewfinder over the rear lcd so achieving and maintaining focus with any depth of field would be a challenge.
I was surprised at how easy this combination was to hand hold and still achieve nice photos with a magnification of approx. 1.9:1.
Also, it was a fantastic pleasure to view something larger than life and try to see it in an artistic style.
Next I tried a reverse mount combination of the M200 with a Sigma 24/2.8 for a magnification ratio of approx. 8.3:1.
The added weight of the Sigma made it much harder to handhold but still produced nice results, though even at f16 the depth of field is very shallow.
This will take a lot more practice to get the my creative sight going.
I have been enjoying this new artistic view of the world so much that I just purchased an old EL-Nikkor 50/2.8 enlarging lens to use in the field (don’t want to take my Rodenstock out into the elements)
and am now on the hunt for an infinity focus objective plus adapter.
Recently I picked up a NIB Tiffen #87 Infrared filter to see if I would enjoy working more with the shorter IR wavelengths (to produce a truer Black and White image) or if I wanted to stay with the 720 and under filters to achieve some color from visible light.
I have always preferred viewing B&W photos and movies to color and when I hold an image in my mind it is almost always in B&W.
The 87 comes in around 795 or just at the baseline of the IR spectrum. Not quite as black as the 093 (830) or 87c (850) but still dark to the human eye.
I do like the contrasty effect the monochrome images have over the false color, though it is difficult to achieve focus.
The majority of my favorite lenses are still manual focus, so I will just have to practice more.
If you can find this filter it is made of glass with a metal ring and well constructed, plus it comes in at about 1/2 the price of other name brands.
I find the images comparable to the Lee 87 film filters for those who already have a holder system.
I did notice under the right light and white balance there were a few shots that did have a hint of blue sky after an attempt at color swapping.
kolarivision.com has an excellent ir lens hotspot database already compiled; however, I noticed most of my older film lenses weren’t included so decided to create a database (bottom of page) testing these lenses on the Pentax K-01.
I remember trying Infrared Photography a few times in my film days and found it difficult and challenging.
It always seemed I was guessing the exposure time and the focus, trying to approximate the red line on the lens distance scale.
Winter Farm IR
Recently, I acquired a Pentax K-01 and had it converted to a full spectrum camera. Unlike film, digital sensors are sensitive to all light waves (UV, visible bands and IR) so most cameras use a hot-mirror to block the infrared bands and pass only visible light.
Winter Mules IR 1
Most conversions replace this hot-mirror and replace it with an IR based filter for a full time conversion, usually in the 720nm range. With the full spectrum conversion the mirror is removed and the IR filter is placed over the lens, much like the film days; however, unlike the film days I can see the image in live view just as if I was looking through a viewfinder.
Winter Mules IR 2
Apparently the new mirror-less systems make fantastic digital infrared cameras. They automatically set accurate exposure and the focus can be determined manually via live view or calibrated for auto focus. Another wonderful aspect of the K-01 is that it will take all my older Pentax K mount lenses.
Winter Tree IR
I now need to experiment with several to determine which will be good performers or or which will be susceptible to flares and hotspots. Infrared is often most noted for its use with contrast or faux colors with vegetation.
Faux Color IR Canal
Here are a few shots from the winter local scenery, a bit different but fun. I look forward to working with the camera as the spring green comes around.