Sunday, February 26, 2017

Non-TTL Speedlights - Nikon

The Nikon SB-24, SB-25, and SB-26 Speedlights.
The closing of  Keeble and Shuchat last year was a blow to photographers on the San Francisco Peninsula. The true, full service stores like Kaufmann's, Brooks', and Gasser's are long gone, victims as much of the digital camera as the rush-rush mentality of today's users. Gone are the days when a dealer and a customer considered themselves friends, and would think nothing of debating the relative merits of one piece of equipment over another.

What I miss most is the assortment of used cameras, lenses, and yes, speedlights that were offered for sale. I appreciated the fact that K & S was very customer friendly when it came to purchasing used equipment. You were given a reasonable amount of time to test your purchase, and if returned within that grace period, you got a full refund.


SB 24 with a Wein Peanut Slave Mounted. Click here. for details.
Why Even Consider These Legacy Speedlights? Cost. It will take you $327 (MSRP) to secure a new SB-700, the entry level iTTL speedlight. (Forget about the SB-400 - It's basically useless). If price is an issue, a used, very serviceable but minimally featured, Nikon SB-24 can be had for a relative song. I purchased a pair of serviceable SB-24s for $50.00 a few years back. And while the price has gone up, reasonably priced specimens can be found on E-Bay.


The Nikon SB-26 - See it? Buy it!
Swiveling Head: Even though the listed Nikons have a head rotation of 180 degrees left / 90 degrees right, it sure beats the 0 degrees left / 0 degrees right of the Vivitar. One could purchase a special Vivitar anatomical flash handle/grip with a swiveling flash shoe, but you'll need a special adapter cable if you want the sensor to continue looking straight ahead.

Beam Angle Adjustment: The Nikon speedlights listed can adjust the flash beam angle automatically (adjusts automatically to match compatible Nikon lenses) or in a manual mode. . 

Build Quality: Put this into perspective: When the Nikon SB-24 was introduced, it cost nearly three times as much as the Vivitar 285. Granted, the Nikons were far more sophisticated in design and execution, but to Vivitar's credit, the 283 and the 285  units were similar in functionality, although not necessarily in sophistication or convenience. If you can find an original Ponder and Best unit, a Nikon user might find it perfectly usable, so long as we understand its limitations.

Supplementary Battery Packs:  Chinese knock-offs of the Nikon supplementary battery pack are available, cheap, and use AA batteries.The packs themselves are backwards compatible: The SD-8a, the designed to work with the SB-28 and newer units, will work on all of the listed speedlights, and will work with the SB-80DX, SB-800, and the SB-900/910. The original SD-8, compatible with the SB-24, SB-25, and SB-26, cannot be used with the SB-28 or anything later.

The Family Lineage: Holding the SB-24, 25, and 26 show a distinct family resemblance.
  • All three share the same flash foot configuration, and left-right sliding power switch.
  • When the wide angle panel and bounce flash panel were added to the SB-25, the head design was duplicated in the SB-26. This gives you an additional "wider than wide" setting*.
  • The three share a similar control  button punch-out placements, but are identical in the SB-25 and 26. 
  • All three have separate rotation and tilt lock buttons.
  • All have PC (Pin Connector, not Personal Computer) flash interfaces. 

Model
Flash Angle
Output Levels
Button Type
Stofen Dome #
Bounce Fill Card
SU-Remote
SB-24
24-85mm
Full – 1/16
Raised Soft
OM-C
No
No
SB-25
24-85mm + 20*
Full – 1/64
Recessed Soft
OM-C
Yes
No
SB-26
24-85mm + 20*
Full – 1/64
Recessed Soft
OM-C
Yes
Yes

Non-TTL Automation: Seven F-stops are available. They are adjusted based on the ISO setting. Intermediate ISO settings are similarly scaled.
When using ISO 200, the F-Stops range from to 2.8 through 22
When using ISO 800, the F-Stops range from to 5.6 through 45
  1. Turn the flash on.
  2. Using the slider, set the flash to Aperture mode.
  3. Press the [Select] until the ASA / ISO value begins to blink.
  4. Use [arrow up] or [arrow down] until the desired ASA/ISO setting appears.
  5. Press the [Select] until the current aperture value begins to blink.
  6. Use [arrow up] or [arrow down] until the desired shooting aperture appears.
  7. Press the select button to end.
  8. Transfer the Aperture and ISO values to your camera manually.
Adjusting Output In The Manual Mode:
  1. Turn the flash on.
  2. Using the slider, set the flash to Manual mode.
  3. Press the [M] and the output values will decrease in 1-stop increments. When you reach the lowest output value, the next press will advance you to Full power, or 1/1
  4. If you need to adjust the output in 1/3 stop increments, press the [Sel] until on output level display appears in the upper right-hand corner of the LCD display.
  5. Output can now be adjusted using the [up arrow] or [down arrow] buttons.
This trio of legacy speedlights are similar in appearance, handling and performance, and finding a reasonably price specimen is not as difficult as you might think. If you do manage to obtain one, click here for some tips on bringing an old speedlight "back to life" by reforming the capacitors.

Sunday, February 19, 2017

Flash Versus Ambient: By The Numbers

Original You Tube video can be seen here.
Warning: Potentially Disturbing Images. I look pretty awful in these photos. Some days I look worse. Can't explain my Conan O'Brian hair.

I made this series of photos for my Outdoor Flash class to illustrate the role existing (ambient) light plays in the foreground - background relationship so far as exposure is concerned. There are three important points to be made:
  • The exposure setting for your background may not be the same as that of your foreground. 
  • The background and foreground settings may not be mutually exclusive.
  • Your camera's internal meter can only meter what it sees, which may be different from what you want.

Photo #1 Exposure: 1/8, F 5.6, ISO 200
I am standing in front of a closed exit door in our main meeting room (Photo #1). I am being lit only by the overhead fluorescent lights. The camera is mounted on a tripod with a subject-camera distance of about 8 feet. Setting the camera's exposure mode to Aperture Priority, I made this photo at F 5.6, my usual starting point. Exposure compensation was set to zero.

For the record the shots were made with an APS sensor Nikon D80 with a zoom lens set to 135mm. This was to insure that the background in all subsequent photos would completely fill the frame. This will be important in determining a suitable background exposure.

Photo #2 Exposure: 1/20, F 5.6, ISO 200
 For this shot (Photo #2), I opened the door to reveal the solar panels in the parking area adjacent to the building. Again shooting in Aperture Priority, I got this image. The Matrix Metering system attempted to reconcile the extreme differences between the background and the foreground, resulting in an exposure where neither background nor foreground were rendered properly, the two extremes being "averaged" mathematically. Clearly, this is not a satisfactory photograph by anyone's standards, but unfortunately, similar to so many I see when indoor subjects are photographed against an  outdoor background.

Photo #3 Exposure: 1/250, F 5.6, ISO 200
To get a handle on a more suitable background exposure, I simply stepped aside and let the camera evaluate the background minus the foreground (me). Without changing the aperture, the camera selected an exposure duration of 1/250 of a second, which is a full 3 1/3 F-Stop difference (Photo #3).

Now we have a slight problem. The preferred exposure time for the background at F 5.6 is 1/250th of a second. Since the D80 can't synchronize a flash at this speed, we need to find some equivalent exposure (aperture/exposure time) combination where the flash will work (maximum exposure 1/200th of a second).

Two factors to consider:
  • Can your speedlight deliver enough light at your chosen aperture?
  • Will the corresponding exposure time introduce noticeable camera shake?
Ideally, I would, in the Manual Exposure Mode, choose a combination from a series of equivalent exposure settings, one that would allow for proper flash synchronization. Any of the following might do:

1/200 @ F 6.3
1/160 @ F 7.1
1/125 @ F 8.0
1/100 @ F 9.0

Photo #4 Exposure: 1/200, F 8.0, ISO 200
As you can see from the caption in Photo #4, my choice of exposure settings underexposed the background by 2/3 of a stop. Notice that the blue sky is bit more saturated (true blue) in Photo #4 than it is in Photo #3, a happy outcome.

Reminder:Your camera needs to be in the Manual Mode, using the aperture and exposure settings you like best. If you leave your camera in Aperture Priority or Shutter Priority, you may wind up with an overexposed background like the one in Photo #2.


Photo #5 Exposure: 1/200, F 8.0, ISO 200, plus speedlight on camera
Adding Flash: For Photo #5, I attached an SB-900 (it was handy) to the camera's hot shoe and made a shot. The background remains exactly the same as it was in Photo #4, but now the foreground is illuminated by the speedlight. Not great lighting by any means, but a simple photo made by exposing the background with a manually selected F-Stop and shutter speed, and then allowing the iTTL speedlight to simply do its thing. As I warned, another in a series of very disturbing photographs.

Photo #6 Exposure: 1/200, F 8.0, ISO 200, plus speedlight off camera
Getting The Flash Off-Camera: By using a light stand and an extension cable, I was able to raise my light source to a height of about 8 feet off the ground, but since I'm 5' 6" tall, this translates to only  2' 6" above the center of my face.

Both Photos #5 and #6 were made with direct flash, which is to say that no modifiers were used. I only wanted to illustrate the interplay between the background and your foreground subject. So long as they the foreground illumination is not affected by the ambient or background illumination, you are free to adjust them both to achieve the effect you want.