Small-Format Pinhole Revisited

This morning I finally ordered the drill bits I need to make some pinholes. Even though I’m very happy with my Lensbaby pinhole optic, I can get wider with a body-cap pinhole, which is also much more compact.

My original plan was to add a 46-52mm step-up ring to the cap so I can add a filter. I’ve read that dust can potentially enter the pinhole and find it’s way onto the sensor, something that can’t happen with the Lensbaby, as its pinhole is printed on clear film. However, I’ve decided against that for the time being, as the area of the pinhole will likely be several magnitudes smaller than any gaps in the average lens.

I also planned on mounting the pinhole plate directly to the underside of the body cap, which means that the pinhole will be 48.5mm from the film plane, requiring a .26mm pinhole. This would be a good focal length for a “normal” angle of view. However, without interfering with the mirror, I can easily recess the pinhole into the body so that the distance is 37.5mm, making for a wider angle of view. That would require a .22mm pinhole. On an APS-C sensor camera such as the Nikon D90 DX format, it would be an approximate focal length of 56.25mm, considerably wider than the Lensbaby at 75mm (50mm x 1.5).

Large Format
I also plan on building some new 4x5 pinhole cameras, one 75mm “wide” (24mm equivalent focal length in the 135 format) and one 150mm “normal” (45mm equivalent in 135 format). These will require .32mm and .45mm holes respectively.

Medium Format
As good as large format pinhole photography is, medium format using 120 film is much more convenient, and less expensive to process. For this, I plan on buying the Holga 120WPC:

Holga 120WPC 6x12cm Pinhole Camera

Its 6x9 and 6x12 formats should provide plenty of area to develop a nice, “sharp”, detailed pinhole image. I’ve seen some really nice examples from this camera, so I feel it’s worth a try.

To make the pinholes, I’ll sandwich several sheets of thin brass painted on one side with superflat black paint between some thin sheets of plastic, and drill them together to make some pinhole blanks. This will prevent the pressure of the drill from distorting the hole in the very thin brass, and prevent the paint from filling the hole. I could also try drilling them first and painting them afterwards, and using the drill to open the hole back up. Then I can trim the plates to suit, and mount them with gaffer’s tape as needed.

For the 4x5 cameras, I’m toying with the idea of making matching body cap pinholes of the same focal length using a tube as an extension. These will not be for picture taking, but for judging exposure. Film has a characteristic known as reciprocity failure, meaning that its sensitivity to light is not linear; the longer the exposure, the less light it absorbs. This means I can use my Nikon N80 to take test shots with the same film stock as 4x5. I can then document the results so that I can take a meter reading and know, with a fair amount of accuracy, what the proper exposure is including the reciprocity factor. At this point, film is too precious to waste, especially 4x5.

New Lens, New Moon

Taken with NIKKOR 70-300mm Zoom, enlarged and sharpened.

I was excited to see how a moon shot would turn out with the Samyang/Phoenix 500mm cat lens, and tonight was clear enough to give it a try.

Moon, courtesy Samyang/Phoenix 500mm f/8 Reflex Lens, native resolution.

Same as above, enlarged and sharpened.

The second photo is the original, un-enhanced version, shot handheld at 1/1000 sec. the third photo is the same image enlarged to the size of the last moon shot I took with the NIKKOR 70-300mm refractive zoom, and sharpened just a bit. The first image is the NIKKOR 70-300mm refractive image.

The experience of taking the photo was most enjoyable. The image appeared quite large in the viewfinder, and once it was focused, there was lots of detail. I took a few shots and chimped; this was the third. The fourth was no better. It was fairly easy to focus, but because we’re going for the absolute maximum resolution here, it had to be DEAD on.

So, I put the camera on a tripod (more to free my hands than anything else) and used Live View to zoom in tight for focusing. It helped a little, but not as much as you’d think. Then, I set the camera to self-timer mode, steadied it, and pressed the shutter release. I did this many times in an attempt to improve over the original (third) image. I never did. Then, clouds started drifting in front of the moon, and I called it a night.

So, this is what I have learned:

Live View has an automatic gain that sets the display brightness, and with such a bright object against a jet black background, all detail was lost. So not much help there.

The tripod does virtually nothing if it’s not both very rigid and placed on the ground, not a deck.

At this magnification, everything works against you, including mirror slap, which is unavoidable in a camera of this class in which you can’t lock the mirror up. So while the image might have been as sharp as the refractive lens’, the additional magnification cancels it out.

But, overall I’m not unhappy with the results, because I know that there are still some technical issues to work out. And, if you look at both images straight out of the camera at their native size, the catadioptric image looks better, because it’s larger and therefore displays more detail. It’s only Photoshop trickery that makes the refractive image look better.

Armed with this knowledge, I’m betting that the 800mm f/8 catadioptric will yield an even better image. From what I’ve read, the other two Samyang catadioptric lenses, the 500mm f/6.3 and the 800mm f/8, are optically superior to the 500mm f/8, though not nearly as compact and well built. I think the 800mm would be well-suited for astronomy, and the 500mm f/8 good for terrestrial work. So, the 800mm is tentatively on my wish list.

What Would I Have Done Differently?
I would have used some sort of optical magnifier to help me focus instead of Live View. Once again, digital is not always the solution.

• I would have added some mass to the camera/tripod assembly to dampen out vibrations.
• I would have used the infrared remote to trigger the camera instead of the self timer.
• I would have placed the tripod on the ground.

Shooting 35mm with the Holga 120

There’s a 35mm film adapter kit available for the Holga 120 which enables you to take standard 3:2 35mm frames. It includes a 36mm x 24mm mask, and a back with the frame counter window covered up. The mask has two plastic brackets on the left side to center the film cartridge, and guides to ensure that the film remains centered on the mask opening. You use the original 120 take-up spool with no additional modifications.


In theory, it should work quite well, although I’m sure the vignetting effect will be missing, and the images will be more tightly cropped as if using a 60mm lens on a standard 35mm camera (slightly longer than a “normal” lens.) Hopefully, I can use the Holga .5x wide angle converter to restore the wide angle effect.

Frame advance will be pretty straightforward; After each picture, I advance 22 clicks. If I wanted to maximize the amount of exposures, I’d reduce the number of clicks by one every other frame to compensate for the increasing diameter of the take-up spool. This of course requires tracking the number of frames taken.

However, in my opinion it’s not the best way to use 35mm film in the 120 Holga. The best way is to modify the standard 6cm x 6cm mask to create a 35mm panoramic adapter. This way, you can take advantage of the full width of the 6cm 120 frame size, plus the full width of the 35mm film, including the sprocket hole area. This is known as “Sprocket Hole” photography, and is quite popular amongst the Lomography community.

So, along with my 35mm adapter kit, I ordered an extra 6cm x 6cm mask. I plan to modify it by adding brackets to center the 35mm cartridge, and possibly add film guides that just barely catch the edge of the film to stop it from curling. But I’m still on the fence about that. Like the standard 36mm x24mm adapter, I would advance the film by clicks, but use 36 to cover the full 6cm width. Or, I could advance less clicks and superimpose the next image on top of the previous one. When processing the film, I’ll ask them not to cut it, so I can decide for myself what constitutes a frame. My Epson V500 scanner should have no problem scanning such a wide frame.

The Annual Autumn Tradition

Today my family and I will be embarking on our annual autumn tradition; a pumkin-picking pilgrimage to Alstedes in Dover. It seems the perfect opportunity load my Holga 120FN with 35mm film and test out the new .5x Wide Angle Adapter.


I’ve estimated that it takes 24 clicks to advance the film to the next frame with a comfortable space between frames. Of course, this space will widen as the diameter of the take-up spool increases, but I don’t feel like complicating things by tracking the number of exposures and compensating. I just want to shoot.

I plan to take this to a consumer lab for processing, so I want to make it as easy for them as possible. Still, I’ll specify no color correction and to leave the film uncut due to the uneven frame spacing. I’ll unload the film at home in a changing bag, the only real hitch in using 35mm film in the Holga 120, due to the lack of a film rewind knob. The changing bag will find a new home with my Holga kit.

Strobism

For the past couple of weeks, I’ve been following strobist.blogspot.com and getting a feel for flash. I’m still working out my flash strategy, and it will likely be based on the Strobist concept. So far, I’m fully in sync with David Hobby’s preachings. Travel light, and work with what you’ve got. So I’m approaching flash cautiously, since again I need to purchase all new equipment. Well, almost

Eventually I’ll be needing two or three light stands, and I’m happy to find that in my original stash I have a nine-foot Smith-Victor stand, and two Manfrotto umbrella adapters with hot-shoe adapters. So, I’ve got a little bit of a head start.

With ten sheets of black coraplast in hand, I’ll be building a few grids, snoots and flags.

Then there’s the flash purchases themselves. I’m pretty much set on the Nikon SB900, since it will work not only as an excellent iTTL flash, but also as an off-camera flash. The very affordable SB600 would be my second flash, due to its compatibility with a wide range of Nikon cameras, including the N80. It has both i-TTL and D-TTL, plus TTL Auto and manual.) For a second backup/third flash I’m considering the Vivitar 285HV, and for Macro work the Sigma-EM 140 DG Macro Ring Flash.

For times when I absolutely, positively have to use flash on-camera, the Custom Brackets CB Junior rotating bracket wins hands down.

First Impressions: Samyang 500mm f/8 Mirror Lens

Samyang/Phoenix 500mm f/8 Reflex (Catadioptric “Mirror”) Telephoto Lens

Those who may think this is a poor quality product are sadly mistaken. The truth is, this lens is manufactured to high-quality standards with a fit and finish comparable to any high quality lens.

There are many misconceptions about mirror lenses that prevent people from buying them. If you understand what their purpose is, and how to get the most out of them, they can achieve things that no other lens can, at a ridiculously low cost.

Ignorance is Bliss

In 1976, when I purchased my first SLR, the Canon AE-1, I pined after the Canon Reflex 500mm f/8. I was intrigued by the donut-shaped bokeh that it produced, seeing it as a unique advantage that no other telephoto lens had. Since then, I’ve always had an affinity for the aesthetic of reflex lenses.

Ironically, while some complain about the quality of the reflex len’s bokeh, others seek to produce creatively shaped bokeh using custom aperture disks. Lensbaby even offers a creative aperture kit for their Optic Swap series of lenses.

I passed up several opportunities to purchase the reflex lens for my Canon AE-1, which of course would have been unusable with my present Nikon Bodies.

Newer, Cheaper, Better

Fast-forward to 2010. By comparison to the reflex lenses of old, the Samyang/Phoenix version is smaller, lighter, has a shorter minimum focus distance, and is quite inexpensive. Here are some specs for comparison:

Canon Reflex 500mm f/8

Lens construction: 3 groups, 6 elements (including mirrors)

Coating: Multicoated-S.S.C (super spectra coating)

Minimum Aperture: f/8

Angle of View: 5°

Minimum Focus Distance: 13.12 ft. (4M)

Filter Type: Rear section filter holder, drop-in type (with 34mm exclusive filter. Regular 1X)


Length: 5.84 in. (146mm)

Diameter: 3.54 in. (90mm)

Weight: 25.04 oz. (710g)

Reflex-NIKKOR C 500mm f/8

Lens construction: 6 groups, 6 elements (including mirrors)

Coating: Multicoated-Nikon Integrated Coating (NIC)

Minimum Aperture: f/8

Angle of View: 5°

Minimum Focus Distance: 5 ft. (1.5M)

Filter Type: Threaded, 39mm (rear), 82mm (front)

Length: 4.57 in. (116mm)

Diameter: 3.5 in. (89mm)

Weight: 29.6 oz. (840g)

Samyang/Phoenix 500mm f/8 MC Mirror

Lens construction: 6 groups, 7 elements (including mirrors)

Minimum Aperture: f/8

Angle of View: 5°

Minimum Focus Distance: 5.6 ft. (1.7M)

Filter Type: Threaded, 31.5mm (rear), 72mm (front)

Length: 3.4 in. (86.5mm)

Diameter: 3.0 in. (76mm)

Weight: 12.7 oz. (360g)

Samyang’s series of mirror lenses are inexpensive by design, not by manufacture. By folding the optical path three times, less material and less glass are employed, and the simplification produces far less chromatic aberration.

These lenses takes on a whole new life with digital photography. Their subdued contrast and saturation can easily be enhanced in post-processing, and if captured in Camera Raw, images that are underexposed to reduce motion blur can be opened up. On higher end cameras with higher ISO capability, they become even more usable. And, they’re so compact and light, you can walk around with them all day to explore far out-of-reach subjects.

Read the review »

New Arrivals: Holga .5x Wide Angle Adapter

Wow, a two-element plastic wide angle lens for my Holga 120FN. Now I can comfortably shoot 35mm film with the 35mm film adapter (mask and back), or as panoramic sprocket-hole with the modified 6x6cm mask.

It slides right over the existing lens covering the distance scale, which is OK, since it’s meant to focus at infinity anyway. It even comes with its own storage pouch, and front and rear caps.

New Arrivals: Samyang 8mm f/3.5 & 500mm f/8

I just unpacked my Samyang long and wide duo. The long is the Phoenix 500mm f/8 Catadioptric (“Mirror”) lens, and the wide is the ProOptic 8mm f/3.5 Fisheye lens. Both are manufactured in Korea by the Samyang company, and are marketed under many other brand names as well.

When it comes to equipment I’m very picky about quality, and the build on these lenses is outstanding. Both are manual focus, unchipped lenses, so they won’t even allow me to use any of the auto exposure modes on my Nikon D90. But this is just fine for the type of work I’ll be using them for. Besides, what’s better than a digital camera with a color histogram?