This is a followup to “From the Practical to the Ridiculous“. I got the sun I wanted to test the Rokinon 800mm and it’s doubler. I also wanted to get really nutty and try the doubler I have for the camera body in addition to the doubler that came with the kit. I’m making the assumption that using a doubler on the already doubled 800mm will result in a 4x increase and not a 3x increase. It’s very possible that I’m wrong. If so, please let me know, so I can edit my descriptions, titles and stuff and learn a bit in the process 
On to the testing!
in addition to the Rokinon, I brought a Sigma 70-300m lens, a 50mm Nikkor lens, the doubler that came with the Rokinon 800mm, a doubler for the body of the camera and a tripod. All of the photos were shot a f/8 on my Nikon D90, as the Rokinon is fixed at that aperture.
The Rokinon is a mirror lens that weighs 2 pounds and has a 3 degree field of view. This and the f/8 make it a tough lens to shoot from the hip with. It can be done, but, you really need to have a tripod or something to steady it against.
For the testing I took general pictures with the 50mm and progressed through the lens lengths to see what kind of magnification and quality I could get. I also have shots of the full moon, as it was a clear night. With these pictures I started with the 800mm and added doublers to get to 3200mm. You can find all of the photos form both posts on Flickr.
The pictures I selected are from the Woodland Reservoir to Carousel Center Mall, which is about 3 miles to the North.
The mall is hard to pick out right away in the 50mm shot. It’s the white line with the blueish speckles almost in the center of the shot. You may need to look at the Large or Original size on Flickr to find it the first time.
Now the mall @300mm
Next @ 800mm – at this point, any movement shakes the image, and I’m having issues setting the shutter to let in enough light and not get blurring from shake. The exposure meter does not work on the D90 with this lens. I have to see if there is a setting on the camera that will enable the meter with this lens, but, that’s a different project
1600mm – More problems with shutter speed and shake, and due to the doubling tube, the center of gravity is far enough out to start tilting the camera down. This wouldn’t be a problem if I had a third arm (or a 2nd tripod), since I had neither, it was fun trying to keep the image in frame and not blurred from the downward motion of the camera
and finally at 3200mm – At this magnification, objects are really to find. It’s hard to focus the camera because any movement of the focus ring will cause blurring. The cooling breeze was enough to cause a lot of shake, not to mention the pounding of the ground as people jogged by.
Yeah, yeah, this is a long article, with a couple of pics. Just hang around for a bit more text and a few more pictures. Yer almost at the end here…
Now for the moon pics. These were taken from a friend’s front yard (the same place I took the Grape Harvest pics)
Moon @ 800mm
1600mm
and at 3200mm
This lens is Ok. At 800mm it’s pretty serviceable but, the subject is gonna have to be pretty still and brightly lit if I decide to use the either of the doublers
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October 15th, 2009 on 11:40 am
[...] More magnification testing with the Rokinon 800mm f/8 Sunny day + housework avoidance = [...]
October 21st, 2009 on 11:21 am
[...] were taken during my Quick Trip to Beaver Lake. Unlike the other images in “more magnification testing” and “from the practical to the ridiculous“, these have been post processed, [...]