Flash coverage for 6x7

[mtngael]

I have a Canon Speedlite 199a that I never used from my 35mm days and a Fuji 6x7 camera. I've only used available light for my photography in the past, but having an upcoming stuff that I'd like to use flash with, can anyone tell me if I'll be able to cover the 6x7 format with what I'm presuming is a flash made for 35mm cameras only. Sorry if it's a dumb question! I hunted around and couldn't find out if a different flash unit is needed for the larger format or if all are created equal. Thanks in advance.

 

[David A. Goldfarb]

You might want a bigger unit for medium format than for 35mm, just because you are likely to be using smaller apertures with medium format, but otherwise, no, there isn't a coverage issue, since the angle of coverage of your lenses is likely to be comparable between the two systems.

 

[MattKing]

The coverage will depend on the field of view of the lens on your 6x7 camera.

For 35mm, the 199a covered the field of view of a 35mm lens unless you use the wide angle attachment, which spread out the light to cover a 24mm lens.

You need to determine the field of view of the lens you are using, and then see if the flash covers it.

I would estimate that if the lens on your 6x7 camera is 65mm or longer, the flash should cover.

 

[lxdude]

It's all about angle of coverage. If the flash will cover the angle of view of the 6x7 lens (horizontally and vertically, as the aspect ratios are different), you will get full coverage.

 

[papagene]

The 90 mm lens on the Fuji is about the same as a 45mm or 50mm on a 35 camera. So the flash should cover. But I agree with David, does the flash have enough power for smaller apertures?

 

[hpulley]

I use my Canon Speedlite 199A with my RB67 Pro S all the time, works great! I have the flash bracket which holds it perfectly. I use a Kaiser hotshoe to PC socket adapter; it fits in the cold shoe on the flash bracket and the short PC cable reaches the socket on the lens without too much extra length to get caught on things.

As usual, bounced flash works best and offers good coverage. Partial bounce using the intermediate angles also works well.

Without the diffuser the 199A covers 35mm lenses on 35mm film which will cover all but the widest RB67 lenses down to the 75mm; without a diffuser it won't cover the 65mm, 50mm and 37mm lenses. With the diffuser the 199A covers 24mm on 35mm film which will cover the 50mm and 65mm RB67 lens just fine but not the 37mm for which bounce would be needed.

 

[mtngael]

Thanks! I should have asked my question better I guess as it was indeed the flash output being sufficient that I was wondering about. And to add to it, since I'm not good at doing my own manual flash math etc., if I would need to set the ASA on my flash diffferently to compensate for the smaller apertures, ie- "fooling" the flash, if that makes any sense.

 

[MattKing]

Thanks! I should have asked my question better I guess as it was indeed the flash output being sufficient that I was wondering about. And to add to it, since I'm not good at doing my own manual flash math etc., if I would need to set the ASA on my flash diffferently to compensate for the smaller apertures, ie- "fooling" the flash, if that makes any sense.

What ISO film are you using?

If you are using ISO 400 (or maybe even 200), the flash has enough power (metric guide number of 30 for ISO 100) to give you some flexibility.

I'm assuming you are using direct flash - not bounce.

For bounce, it's a bit of a challenge.

FWIW, I rarely use flash with apertures larger than f/5.6, so I rarely find a f/3.5 or f/4.5 lens a problem when using flash (as compared to actually seeing well enough to focus).

 

[hpulley]

A Polaroid back with Fuji instant film is good for checking lighting first but I have no trouble with even 100 ISO film which you can bounce at mid 'green' power for f/4.5 or so. You can't fool the flash, it is too dumb to fool really. Manual setting means yoy set the range otherwise you pick a power and it shuts off when it detects a return flash. You need to set the right aperture for corrwct exposure though most neg films are fine a little over or underexposed. 400 ISO film is fine grained enough for easy use.

 

[mtngael]

mid 'green' power for f/4.5 or so. You can't fool the flash, it is too dumb to fool really.

Thanks for the info, I guess a better way to put it would be this; would setting the flash's ISO higher than the one actually used be a way to get a more accurate setting for this use? I'm sure there's a way to figure it out on my own but as I said, all the theory, GN stuff etc. is a little beyond me as 99.9% of my stuff has been available light. I was just wondering if there was an idiot-proof way for me to set my flash so I don't have to think!

Or perhaps I should stick to available light!

 

[MattKing]

Thanks for the info, I guess a better way to put it would be this; would setting the flash's ISO higher than the one actually used be a way to get a more accurate setting for this use? I'm sure there's a way to figure it out on my own but as I said, all the theory, GN stuff etc. is a little beyond me as 99.9% of my stuff has been available light. I was just wondering if there was an idiot-proof way for me to set my flash so I don't have to think!

Or perhaps I should stick to available light!

You are over-thinking this.

If for the film you are using, the flash auto suggests f/5.6, that is what you set on your camera.

If for the film you are using, the flash auto suggests f/8, that is what you set on your camera.

If for the film you are using, the flash auto suggests f/4.5, (1/3 of a stop smaller than f/4) that is what you set on your camera.

The only time you adjust the f/stop away from what is recommended by the flash is when the reflectance of the subject and the surroundings is either much higher, or much lower than average (just like when you are shooting with existing light).

 

[mtngael]

You are over-thinking this.

The only time you adjust the f/stop away from what is recommended by the flash is when the reflectance of the subject and the surroundings is either much higher, or much lower than average (just like when you are shooting with existing light).

Thanks Matt, I probably was over-thinking it. I also wasn't asking my question very well either though! ie- not specifying *what* kind of flash I was looking for (fill type flash with a non TTL meter camera, no ability to dial down flash output incrementally, smaller apertures etc.). I did wonder if the apertures I'd be likely to be using with this camera might have anything to do with it but is sounds like perhaps not.

One of the things I was trying to figured out was answered very helpfully via PM.

However I did realize that there's another thing about flash that I'm hopelessly clueless about but that's not specific to MF or this camera so I'll post it in the proper forum category!

 

[hpulley]

You asked about the Canon Speedlite 199A and the RB67 and I have both so my response was not generic, it was specific. If you have that flash and a 6x7 camera then indeed they will work fine together using a PC socket, I use this combo all the time with a Kaiser PC to hotshoe adapter on the Mamiya flash bracket.

Now, if the Fuji 67 has a hotshoe then the 199A won't work in any auto modes. You can use it on the hotshoe but you'll have to use it as a dumb flash. It is only Auto on the Canon A-series (AE-1, AE-1 Program, AV-1, AT-1, A-1 I think).

Flash light is flash light. The ISO dial on the back doesn't do anything to the flash at all, it just tells YOU what aperture to use with what film in the red/green/yellow auto modes (check the distances) or the aperture to use at what distance with what film for the grey manual setting. The dial is not actually connected to anything in the 199A flash, it is just a guide number calculation aid really.

 

[mtngael]

Ah...thanks. I didn't realize that flash would only do auto with those. It's actually what came with my AE-1 but I've never used flash before now so I didn't look into that (don't have the manual either!) I may have a way to use it w/o the PC cable though that will at least suit my needs for now though.

 

[MattKing]

My recollection is that the 199A offers full auto exposure with the A1 and AE1, whereas with other cameras it offers auto exposure, provided you manually set the correct shutter speed and set your lens' f/stop in accordance with the flash calculator dial.

My review of the manual from Mike Butkus' site confirms that:

Dead Link Removed

I'd suggest a donation to Mr. Butkus if you find the manual useful.

 

[aoresteen]

The 90 mm lens on the Fuji is about the same as a 45mm or 50mm on a 35 camera. So the flash should cover. But I agree with David, does the flash have enough power for smaller apertures?

Depends on the distance that the flash is from the subject.