Small Flash: distance scale, Thyristor or not?

[Robland]

I have 2 "new" flash units, Metz Mecablitz 20 B5 and Vivitar Auto Thyristor 225. I purchased to go with my 1950 era 6x6 folder with Prontor SV shutter. The Vivitar came with a PC Sync cord and for the Metz I added a cord. I'm evaluating their usage and want to keep the most versatile unit. My goal is to use inside (night), with people, specifically at special occasions, birthdays etc. Our home is not brightly lit but adequate. I need a fill flash to brighten the faces and bring out detail in the shadows, without overpowering the scene.

My experience has always been with more modern cameras and flash.

The Prontor has a M and X setting for flash, I'm using X and do not understand which shutter speed would match the 5.6 setting on the flash, I assume 50 or 100, but that's a 1 stop variable and could be all the difference between acceptable or wasted effort.

The Vivitar has a "thryistor" or sensor on the front to read the light coming back from the scene and shutting down when enough is reached. This is my assumption. The setting on the back shows a range of distance. Note in the picture the ISO 100, F5.6 with the blue range between 4 and 12 feet. If I keep my subjects within this range then 5.6 would be a good setting, but at which shutter speed.

The Metz is new, looks unused (both purchased on auction site). It does not have a sensor on the front and therefore less attractive (assuming the dang sensor works the way I described above). The setting suggests that with each movement from subject to cameras I would need to adjust the aperture from 5.6 at 10 feet to F/22 for as close as 3 feet, that's a 3 stop swing and a lot of fiddeling.

Question:
Are my descriptions accurate.
Is the latitude in exposure enough to allow a 1-2 stop swing without adjustment, (using the Metz)

 

[Spyro]

The shutter speed is irrelevant when you're using flash, because the flash speed (very fast) becomes your shutter speed ie it freezes action within range. Just make sure you dont go faster than the sync speed. The thyristor is a simple machine, you dial into the flash your film's ISO and camera's aperture (and repeat everytime you change them) and it gives you a distance range within which you should put your subject. Then it does the rest, and it can be surprisingly accurate.

To be honest I wouldnt bother with any of that, I'd just grab a digital camera and run some tests the day before, find a couple of standard manual settings that you're happy with (eg for close up portrait, group, outdoors) and stick with them all night.

 

[sevo]

Leaf shutters sync at almost every speed - small flashes have a maximum duration of usually less than 1/500s, a speed which only very few leaf shutters ever reached. Unless you operate slow grid powered studio flashes, you can assume every speed to be a sync speed on cameras with leaf shutters.

The all-manual distance table method is perfectly accurate, but it needs permanent attention and interaction. For normal subjects, sensor automation ("thyristor" on yours) will not be much worse - but it will be way off if there are large dark areas or a distant background in the image, so you'll have to learn how to adjust or when to switch to manual with aperture setting by distance.

When mixing ambient and flash, simply try to expose half either way to start with - that is, take a exposure reading for the aperture the flash suggests, and expose at that time and with that flash setting, but stop down by one stop.

 

[Ronald M]

Use slow shutter speeds to pick up ambient light, 1/15 say at 5.6 under exposing around 1 stop and let the flash expose the subject. Called fill flash. The lamps will get a nice warm glow if incandescent. If flluorescent, you need to filter the lens and flash to match.

Start saving incandescent bulbs now because you will not be able to do it the with the new bulbs. You get screwed up light from them. A digi cam helps to sort it out.
I don`t have a one of them in my house, but I have horded 5 cases of various wattage bulbs. Since I use dimmers, they will last a life time.

Omni bounce from Stofen is what I use on my Vivitar 285. It gives a ceiling bounce and kicks some light forward. That plus slow speeds is the best you can do and remain portable.

Google Stofen.

 

[oftheherd]

First of all, your Vivitar is not showing a distance of 4 to 12 feet. It is 12 feet or 4 meters. So, with ASA (ISO) 100, f/5.6, your best distance to your subject is 4 meters, or 12 feet. That will give your subject at that distance, its best exposure.

You are talking about a primary use inside a house. That implies the possibility of more than one subject, at different distances. As long as they aren't more than 2 - 3 feet from each other, you should still get usable photos. You will be aided by film latitude and bounce from ceilings and/or walls. That will vary depending on exactly where you flash is pointed and the reflectivity of the ceiling/walls.

I don't know your camera, but from other's postings, it is apparently with leaf shutters in the lens. If so, put the shutter on X sync and don't worry about the shutter speed to flash duration, as sevo pointed out above.

Practice, practice, practice. You won't nail every shot even after you get good at it. But you will mess up fewer and fewer all the time. You should also try to find books on the use of flash in non-automatic mode (exactly what you need for the photography you want), or check out the very informative site of Mr. Hicks at www.rogerandfrances.com/ where along with a lot of other things, you will find information on flash. Google others as well, since some people give good information that they, and those of us who are used to it, understand perfectly. Those just trying to learn, may not find everyone's so clear.

Good luck and don't hesitate to ask questions any time.

EDIT: I should have read closer myself. Good you have a shutter on a folder that takes flash. Many didn't. You mention thyristor. You are correct that is shunts the charge away from the flash bulb, so giving on the flash needed based on the sensor telling it there is enough light. For the type of photography you mention, that won't work much of the time, since you will probably have distant backgrounds, and light bulbs in the photo.

Most of the time, if I were you, I would rely on the distance settings on the back of the flashes. The manufacturer spent time and money getting them as accurate as possible.

Again, practice and experimentation are your friends. Photography is an art, but it has its tools that require skill to use properly.

 

[charjohncarter]

The Vivitar looks like it has two auto modes: blue and red. It appears that the red mode would be using f2.8 and the blue mode f5.6 at 12 feet (4meters)( ISO100). These usually came with a manual mode, too. The GN (guide number) of the Metz may be higher and therefore more useful. I would keep both if you can. It is nice to use one as a slave at times especially indoors to light a wall.

Again, you have to practice, I learn something new every time I use flash (it is the hardest thing in photography). But as above has said; expose for ambient light (using shutter speed) and learn how to do fill flash. Don't discount the manual setting, but the auto works well enough for worry free shooting.

 

[chris00nj]

The Vivitar flash has the same auto settings as my Metz 20 C-2. The distance you see is the maximum distance. Just stay within the distance and the auto thyristor will do the rest. It's simple.

The max distances also assumes direct flash. If you bounce the flash off the ceiling, then you will lose power. If I want to bounce I'll use the f/2.8 setting, to allow for the flash to have some extra capacity. The flash should also have an "ok" light which indicates that the auto thryistor thinks that enough light hit the subject.

The Vivitar should be easy to use and surprisingly accurate.
I've used the Metz 20 C-2 with good results with Kodachrome 64 (set for ISO 41):

Zeiss Ikonta 524/2 (folding 6x9) with a Metz 36 C-2 bounced off the ceiling, Portra 400NC:

I like to bounce off a low ceiling, but don't rush to get a diffuser. I've had more problems when using diffusers than anything.

Also learn to drag the shutter if you are taking pictures of people in a larger room. This prevents your subjects from looking like they were taken in a dark cave. If normal exposure would call for f/2.8, 1/30, ISO 400, then set your camera's setting to f/2.8, 1/125, ISO 400 (two stops underexposed). Your flash will correctly expose the subject due to the auto thyristor, but the extra ambient light will help give a wee bit of exposure to the background.