Using an Electronic Flash with a Minox B

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I have a Minox B. The B has a flash sync built into it, near the light meter. I also have a small vivitar 251 Electronic flash that has a cord which fits into the flash connection of the B. At almost all speeds, when the flash is connected to the B, the flash will fire. However I think that this synchronization is set up for bulb flashes which reach their maximum brightness much slower than electronic flashed. What speed should I set the B so that it works with this flash. I am assuming that it should be very slow, perhaps around 20. Also, because the minox only has 1 f-stop (3.5) how do you set up the flash for different distances? Must you use different film for different distances? Also what effective f-stop does the nuetral density filter that is built in give you?

Thanks so much! Kay

-- Catherine Coz (cc473@is9.nyu.edu), May 11, 1999

Answers

Kay, if I use 1/100 speed on my B, I found out that the film missed the flash; at 1/50 it was OK-- the top speed on different B may be different, 1/30 is a safe number to use.

Unless your flash has automatic control, the only way you can some how control distance is using the ND filter, which give you 2x factor. Or you may use a thin handkerchief or thin tissue paper to cover the flash to further reduce the intensity of the flash light; this will give you another 2x to 4x reduction.

I some times use a Vivitar 285 flash , which is automatic.

-- martin tai (martin.tai@capcanada.com), May 11, 1999.


Setting the correct distance is slightly more complicated, the Vivitar 251 flash, like many other flashes has an automatic setting, However this simply means that you must keep your camera at a certain f-stop, which corresponds to the speed of film you have. This is a little complicated for a beginner but once understood is easy to use in a camera with variable f-stops. You simply set the flash to automatic, dial in the correct ISA, ASA or DIN and leave the camera on the same f-stop for all of your flash pictures. The problem with the minox is that you can not set the f-stop. For instance the 251 model, for any distance out to 13ft (4m) you set the f-stop to 2.8 for 25 ASA film, 5.6 for 100 ASA film, 16 for 800 ASA film etc. etc. Unfortunately you can not do this with a minox. The solution is to do what Martin said, 1 use the ND filter and green filter if you are using black and white, and 2 use a piece of paper taped to the flash (this has an added benefit of softening the light, making shadows less sharp and more pleasant). The camera is normally at 3.5, Green filter would be around 5.6, the ND filter around 8. Combine this with some experimentation with different papers to cover the flash and you have opened up a range of distance/f-stop/film speed combinations with which the flash can be used. HOWEVER, putting a piece of paper over the flash on automatic mode does nothing, the flash will simply give more power to the flash until the sensor reads that it is the correct exposure or no more power can be given, you can only use that trick when you are using the flash in manual mode. Just remember that overexposing is MUCH better than underexposing, especially with flash pictures, and especially with ugly subjects who have terrible complexion *-)!!!!!!

By the way the 251 Model is an excellent flash to use with the B, its cheap, small (only twice the of the minox b, the same length but double the width, it easily fits in one's pocket) I glued a piece of rubber on to the top of mine so that I can squeeze the camera and flash together and hold both of them at the same time, with the B on top of the flash, red-eye is a problem with this set up, but the flash is easily moved away from the camera if you are shooting color. Also, since the flash naturally overexposes just a little bit if it is left on automatic with 25 ASA film, this is what I use almost exclusively, good grain and overexposure at the correct f-stop, nothing could be more perfect, usually I use tech-pan 25 or pull a role of slide film down to 25.

-- George Maltezos (George@Maltezos.com), May 11, 1999.


Kay, In common with most cameras of that vintage, synch speeds were timed for slower flash bulb speeds. The recommended factory synch settings for the older Minox models are listed on the leaflet that came with my Minox 8x11 electronic flash. The B and IIIs are 1/20th and the BL and C are 1/30th, and on the LX, use the flash icon on the dial. I suspect you could get away with 1/30th on a B and a IIIs as the shutter is mechanically the same as a BL. I always used 1/30th on my BL. Once I tried the BL at 1/60th, based on a new revised factory leaflet that came with a newer 8x11 flash that was enclosed in my TLX set and got only half of the frame exposed by the flash. I went back to 1/3oth and have had no further problems. The electronic flash must be timed to fire at the instant both shutter blades are wide open. If the speed is set too fast, the second blade has already started to close when the flash goes off, thus part of the negative is darkened and part is exposed correctly, as the blade has already closed over the dark section of the negative.

-- Michael J. Vorrasi (MVorr99@aol.com), May 11, 1999.

I do what the leaflet of the EC flash says: For Minox B use 1/50, it's working OK. Maybe there is some individual variation between cameras. My photographs using flash are coming out with too sharp shadows, I'll try some paper or kerchief to soften the light.

-- Wolfgang Fischer (wolfischer@hotmail.com), May 12, 1999.

I'm using a IIIS, and while 1/20 may the right setting for bulbs, I have had EXCELLENT results with electronic flash at 1/100. I use a Vivitar 2800 on an 8" PC cord, flash in the left hand, camera in the right. I use this flash's lesser Auto setting, which is rated f/4 for 100-speed film: since I always use 100-speed film, and the difference from f/4 to f/3.5 is neglible for print film, exposures are usually fine.

I have also tested the flash at 1/50 and 1/200; results were okay, although there was a hint of falloff. So when I want to use my electronic flash with the IIIS, 1/100 seems to be the way to go. Of course, your results may vary...

-- Michael Goldfarb (mgoldfar@mobius-inc.com), June 04, 1999.



Catherine,

You've been fairly well apprised as to the correct shutter speed to select. Let me add a little to this discussion regarding the selection of a flash and how you can maximize its use for different distances and/or the use of flash fill for outdoor daylight pics.

First, and foremost you MUST have a flash having a variable output selector. For purposes of this discussion (and for purposes of economical choices out there) I will refer to the Vivitar 285 and the 283 with the optional VP-1. The VP-1 is the Variable Power Sensor designed to replace the 283's standard auto sensor. Its available at B+H for about $19.

Second, now that you have one of these babies in your hand how do you calculate the flash output and set it so it'll work with your Minox? Do the following:

a) Always keep in mind that the scales on the 285 and the 283 do nothing more than give you information. They are primarily designed to tell you how far your flash will be effective at a give ASA, f/stop and maximum distance for any give auto setting color code set by the sensor on the front of the flash. Here is where you can help your MINOX with its fixed f/stop. The 285 and the 283 with its VP-1 sensor allow you to modulate the DURATION of the flash by cutting it in fractions: 1/2, 1/4, & 1/16 for the 285 and an expanded range up to 1/64th (!!) for the 283 with the VP-1.

Lets apply it: with an ASA of 100 and a full manual flash setting your f/3.5 will mandate taking pictures with the flash approximately 40 feet away. Not too practical. However, by reducing the output four stops to a 1/16th setting you are now in the traditional poitrait range of about 8 feet. Too close? Move the settingto a 1/4th and your f/3.5 is set for flash exposure at a distance of about 16 feet. The same calculations are possible with the (more affordable) 283 equipped with the VP-1. Just set the reduction of stops as needed to accomodate your film speed and anticipated shot distance.

What about flash fill for outdoor shots? Do the above calculations and then again reduce the flash output by one or two stops. BUT its very difficult to "arrange". Eg: ASA 25, required f/3.5 and required flash sync of about 1/30. You're in a box here as there are no variables you can adjust on your camera. If you're lucky enough to be in the ball park with good exposure at 1/30 th shutter speed you can add just a little flash. Lets say you're taking a shot where the ambient light provides for good exposure as above. Check the flash dial: the above settings provide that at full manual the required distance must be about 18 - 20 feet. It'll be properly exposed but the shot will look artificial as the total light will be from the flash and nothing from the ambient light. Tone it down two stops (1/4 power) and you can take the same shot at the SAME DISTANCE with a wonderful flash fill.

To do the above you need the variable power capibilities of Vivitars (cheap used) or other flashes on the market.

Good luck & regards

Steve

-- Steve Dunn (bicycle55@blazenet.net), January 01, 2000.


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