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Monday, December 31, 2012

••◊ Zeiss ZF.2 lenses for filmmaking/video

The Zeiss ZF.2 lenses have become popular for low budget filmmakers for a couple reasons.
  1. You can adapt the Nikon F-mount to Canon EOS, Sony E-mount, or even PL-mount.
  2. They are much lower cost than CP.2's, but based on the exact same glass.
  3. High quality precision optics
  4. Great flare control at wide apertures. Much better than most pro-sumer lenses.
  5. The aperture ring can be de-clicked for cinema style smooth aperture control.
  6. It's easy enough to add a lens gear (mostly).
What I'm going to discuss here is my personal experiences with trying to use these lenses as a film making tool. Let's start with the lens used in a matte box. As you can see below the stock Zeiss lenses all come with a beautiful silver anodized front ring. This is completely benign when used as a still lens, but behind an ND filter it becomes troublesome. While I was out shooting plates at a local park in mid day sun I noticed some flare problems even though I had the matte box flags closed down to control side spill. The silver front ring was likely reflecting back onto the ND filter. The easiest way to fix this is to add a cheap filter step up adapter that's matte black; in this case to 77mm (second photo below). My circular polarizer has a 77mm thread mount, so that was the logical choice. Also the Zeiss ZF.2 lenses are inconsistent in front ring size, so it's good to standardize this filter thread size for the economics of having a common screw on filter size. As an added bonus the step up adapter conveniently grabs onto the matte box bellows, which means you don't have to mess around with the bellows being caught in a telescoping lens barrel!

So, speaking of telescoping lens barrels...this example is from my 50mm macro lens. Notice how is almost doubles in height when focusing from infinity to macro? You need to take this mechanical displacement into account when mounting the lens in back of the matte box filters so you don't accidentally crash into them! This is definitely an issue that true cinema lenses don't face. They tend to have the same front diameter, the same length, and the same placement of lens gears in order to ease the headache of on-set lens changes. That's one of the reasons why people choose the Zeiss CP.2's instead of the ZF.2's. If your talent is costing $1k/hour then it better not take more than 5 minutes to change a lens and reconfigure the camera!

The last point I'm going to discuss is the necessary modifications needed to make the lens ready for film making. Typically these lenses need a focus gear and de-clicking of the aperture ring. For those not daring enough to do it themselves, service shops like Duclos in Los Angeles offer it as a turn-key solution. Video Gear sells the Novoflex adapters to convert the lens to whatever mount you need and the filter adapters area incredibly cheap online. So all you really need is the gear and de-clicking.

Now you may ask why I didn't use a el-cheapo zip gear? ...and there lies one of the first problems I had to solve. The 50mm Zeiss ZF.2 has a 349-degree focus barrel rotation! There's no room to put the zip tie or screw attachment points! The 35mm Zeiss on the other hand has about a 1/3rd turn focus barrel rotation, so it could potentially be used with a cheap off the shelf zip gear. If you use a rigid mount gear on one lens and a zip gear on another you'll have the same lens changing issue. If you have the budget I recommend making your lenses as mechanically interchangeable as possible.

What I also took note of is that the Zeiss 35mm lens is an incredibly heavy beast. It weighs more than my 24-70mm L-series Canon zoom lens and that thing is a beast to lug around! At least is doesn't telescope.

When purchasing the 100mm macro lens the telescoping becomes an even greater factor. Both the focus barrel and front ring translate! So you can use an extra wide lens gear, but even with that I'm not sure you'll be able to use a follow focus over the entire focus range - I haven't tried it myself. That lens is really meant for extreme macro detail shots anyway, so it's probably not a big deal to not be able to use a follow focus - in most cases.

Other than the ergonomics of trying to make a low cost SLR lens work for cinema, these really area excellent precision made lenses. They do breathe while racking focus, just like any other SLR lens, but the CP2.s do that as well. It's only when you step up to the big budget lenses that those problems go away and in that case it makes more sense to rent.

Sunday, December 30, 2012

••◊ Catching up with Christmas in Seattle, part 2

Continuing on from part 1 of my Seattle photo expedition...After visiting the local Seattle parks and a quick dunch (dinner-lunch) at Cafe Flora we headed back through the city's Capitol Hill district in search of an I-5 on ramp. I took some pictures of the golden sunset through the city buildings as we were driving along.

What would be trip to Seattle without random sidewalk statues of Jimi Hendrix?  Heck, Paul Allen built a whole museum for Jimi just a few miles away.

Then there are random, but common city views of Seattle. Growing up I hardly remember a wooden power pole that wasn't stapled to death with fliers for local bands and city dweller events. I'm sure there's a documentary story in there somewhere.

During the flight home I decided to take pictures of things that I could identify from the air starting with Mt. Rainer...

...random mountains over central California...

...South San Francisco (sorry, we flew over the main city before reaching 10,000 feet for "approved electronic devices")...

...The metropolitan Los Angles area. Downtown is so incredibly small compared to the urban sprawl. If you look at the far let of the first picture below, 1/3rd up from the bottom you can see the white blur of the "HOLLYWOOD" sign on the hillside just north of downtown...

...Finally, my neighborhood. My mom doesn't believe me, but you can actually see my house. ...and no, Sarah Palin, you can't see Russia from there.

Saturday, December 29, 2012

••◊ Catching up with Christmas in Seattle, part 1

Well...mom did it again this year. She convinced me to come up to Seattle for the holidays - so fly I did.  The day started out with a rather early 4am beep, beep, beep of my alarm going off.  That, followed by some grumbling of "what the hell was I thinking taking an 8am flight on Christmas Eve?"  I was expecting a full on wrestling match inspired by the WWE at the airport with people lined up from Lindbergh all the way back to the embarcadero downtown - Police pepper spraying line cutters - The TSA out with tasers in hand...  As it turned out the airport was quite empty at that hour and I basically walked right up to the gate (note to self for next year).  Alaska had a full flight, so they asked for volunteers for checked baggage.  No $20 fee?...sounds good to me.  The only glitch I noticed is a BSOD Windows computer at the gate (see photo below).

After arriving in Washington I spend the majority of the day with my Aunt.  Keeping with tradition, we had to see a movie at Christmas time.  Hitchcock was playing at the local theater so we settled on joining the other dozen or so wayward Chistmas escapees.  I read about the film in the journal of the ASC before I left.  The movie was helmed by a first time director, but lens'ed by Jeff Cronenweth, best known for his work with David Fincher (The Social Network, The Girl with the Dragon Tattoo...etc).  It's a neat little film.  Worth seeing on a rainy weekend day.

After our new tradition (Indian food on Christmas Eve) we all hopped in a rented van and headed out for Xmas light viewing.  By this time my back was killing me from sitting all day and I had an exhaustion/stress headache, so you'll have to pardon my lack of enthusiasm.  We stopped at a house in West Seattle that runs a light show and features its own radio station to support charity.  I had to supply a couple pictures here to show the house in various states of lighting.  The best part was a rendition of "I AM SANTA CLAUS!" sang over the melody of Black Sabbath's "Ironman."  Yes, that really happened.

Next up was a quick jaunt across town to Kerry Park for a full downtown Seattle view.

Not being a big Christmas fan, that's all you're getting out of me about Christmas.  No one wants to see family Christmas photos anyway.  I didn't take any.

On Thursday my mom and I went park hopping with the first stop at Volunteer Park up on Capitol Hill.  In all my years living in Seattle and the bicycle racing I did at Volunteer Park I never really took the time to notice the park itself.  They have a nature conservatory green house there.  When I first walked in my glasses immediately fogged up from the transition of 40-something to 60-70-something degrees with humidity.  As you can see below, I took a few photos of the various flora, ferns, and cactus.  I'm not a nature photographer, so you're just going to have to forgive the lack of imaginative photography.

I'll cover more of the trip in part 2.

Saturday, December 22, 2012

••◊ Novoflex lens adapters

I recently started investing in some nicer glass for the front of my camera, i.e. Zeiss ZF.2's.  The problem is that I have a 5D mark II, currently, and I plan to move up to a Sony video camera next year.  ZF.2's are Nikon mount lenses and the 5D and FS-700...etc are Canon EF mount and Sony E-mount respectively.  Short of taking out a second mortgage and selling a kidney to buy a set of CP.2's I needed a solution to adapt the Nikon mount to whatever camera I'm using at the time.  In walks Novoflex(dah dah dummmm.....dramatic hero pause).  Below is a picture of three adapters my local dealer sells for Nikon lens to EF mount, Micro Four-Thirds lens to Canon FD and Nikon lens to Sony E-mount (left to right).

One of the problems I immediately noticed out of the box is that the lens was loose on mount.  The pro-sumer grade EF mount is normally a bit loose, even with an L series lens.  That side was actually equivalent to my Canon lens being mounted - no big deal.  The Nikon lens mount, however, was unreasonably loose.  So loose that the lens would shift around if I tried to use it with a follow focus.  That's no good.  At first I was thinking that this adapter was an overpriced hunk of junk and I emailed the Novoflex support to see if there was anything they could do, including return my money.  The helpful support person sent me a photo showing a picture like the one below.  It turns out that lens adapter tolerance is a well known issue.  Just read the reviews on Amazon and whatever site that talk about all the problems with cheap adapters - 1000 of reviews!  Using a small screwdriver I very slightly pried open the spring slots and viola!...The ZF.2 was rock solid.  I wish I could say the same for Canon's EF mount on the 5D (it's really not **THAT** bad, but still).

By now you probably noticed the large blue lever on the side of the adapter. This is for manual control of the lens aperture.  In theory it seems like a convenient feature, but in practice it's not really useful.  For camera operators like me, I need to know the actual value of the aperture so when I meter the light in the scene I know the lights are set correctly.  Using the lever is kinda of hap hazard and not the way I prefer to work.  The ZF.2's include a manual aperture ring, which is my preferred way of working.

In order to mount up the Novoflex adapter I recommend to first set the lens aperture to it's smallest value; f/22 in this case.  In the second picture below you'll see that the adapter's small silver tab near the top of the picture is just to the right of the black lens aperture control lever at the left.  This is the way you'll need to line up the adapter for mounting.  In the third picture you'll see the silver tab has been rotated counter-clockwise to butt up to the lens aperture lever.  Then it's just a matter of lining up the red dot (first picture) to the red dot on the EF mount and mounting the lens as you would any other Canon lens.

When I upgrade to a real video camera I plan on purchasing the Nikon lens to E-mount adapter.  Hopefully that works just as well.

Sunday, December 16, 2012

••◊ Zeiss versus Canon lenses versus Samyang

I borrowed a focus chart over the weekend to do a few tests on my lenses.  After paying an atrocious amount of money for a set of Zeiss primes I wanted to see if they were really worth it.  What I had available is a mixture of popular lenses used with a DLSR for video.  So I realize that the lenses aren't quite the same value, performance range, or expected performance.  It's what *I* had available to me.  I have a Canon 24-70mm f/2.8 L series, Zeiss 50mm f/2 macro, and Zeiss 35mm f/1.4.  My friend brought over his Canon 24-105mm f/4 L series and Samyang 35mm f/1.4.

First, I'll say that the Zeiss lenses are really top notch precision quality.  Their lower end SLR lenses are made by Cosina in Japan, but these clearly aren't spec'd like Canon or Nikon lenses.  No plastic or rubber, nor tolerance slop, as I've become accustomed to from Canon L series lenses.  Even the lens shades are metal!  But, more importantly, I really wanted to look at the optical quality of the lenses.  I'll get into the ergonomics of the design in a future post.

Let's start with a comparison of crops from the lower left corner of the focus chart using the 35mm focal length at f/4.  Frankly, they're all really good with the exception of the 24-105mm Canon, which is starting to show chromatic aberration and distortion.  The Samyang actually has really great performance, which is surprising given the bargain price - most likely due to the mostly plastic construction of this lens.  Notice how the Zeiss still has detail in the "A" pattern?  Very nice.

Canon 24-70mm @ 35mm
Canon 24-105 @ 35mm
Samyang 35mm
Zeiss 35mm

Then lets look at the same plots at 50mm f/4.  The 24-70 and Zeiss seem pretty close, with the exception of some aliasing in the A pattern on the Canon lens.  However, both Canons still show distortion even at this "normal" focal length.  The aliasing on the 24-70mm might have something to do with the distortion skewing the lines slightly.

Canon 24-70mm @ 50mm
Canon 24-105mm @ 50mm
Zeiss 50mm

This is all cool, but what about pictures in the real world?  For that I went to a nearby hillside and took some pictures while focused at infinity. One thing I'm still getting used to is the Zeiss lenses and their hard stop at infinity. The infinity markings on the Canons aren't always dead on. You really have to focus them via live view to know you have a sharp image. Below are the same outlook at 35 and 50mm using each of the lenses.

Although the Canon 24-70mm is still really good, it doesn't match the Samyang nor Zeiss.  The Canon 24-105 is definitely more distorting and blurry. The Zeiss and Samyang were both excellent.  I invite you to download the images and examine them for yourself.  The images below are 960x640px, so you're not seeing the full story by just looking at the images in in the blog post.  Blogger downscales everything to 320px wide.

Overall view
Canon 24-70mm @ 35mm
Canon 24-105mm @ 35mm
Samyang 35mm
Zeiss 35mm
Canon 24-70mm @ 50mm
Canon 25-105 @ 50mm
Zeiss 50mm

I fully realize I'm being overly nit picky here, but when you pay so much for a lens you deserve to be.  What I can say is that the Zeiss and Samyang seem to be matched pretty well optically.  Both are excellent.  It appears as though what you're really paying for with the Zeiss is the all metal bomb-proof construction and tight German tolerance.  What I haven't been able to investigate is the bokeh, flare control, and transmission characteristics.  Frankly I'd rather be out shooting than doing lens tests, however it's the end of the year and production is pretty much shut down until the hangovers from New Year's Eve wear off.