New to 4x5, fault finding help?

[brucemuir]

To test x sync
take the back/groundglass off so you can look into the bellows (from the rear) through the lens.

Open the lens wide open (5.6?) and set the shutter to whatever speed you like but test them all when you get the chance.
Fire the shutter with camera and flash pointed at a blank wall and you should see uniform illumination through the lens with no sign of the shutter blades.


edit: I'd put the rayflash aside for now until you make sure everything is kosher.
that thing will probably rob some power so the quide # will no longer apply.

[mike-o]

I have to agree with Brian. You've got too many variables going on with equipment you've never used before. If nothing else, drop the flash and expose in daylight with a light meter. I suspect a bad light leak, maybe your holder. It's really easy to check the camera and bellows for a light leak with a flashlight in a dark room.

[jnanian]

virtually no access to a darkroom.....though I had originally acquired the camera with a view to shooting tintypes. or making a camera adapter for a DSLR.

the reason for shooting instant is the immediate feedback, given that I am a novice. significantly shortens the learning curve, the way I look at it.

Regarding overexposure, yes that would be a possibility but, how does the fact that pulling the tab on a print in the second pack, and having it come out white, after the #1 print which was also unexposed, was developed as black, sit? Unless I somehow managed to overexpose it so much that light migrated thru the material of the #2 print and fogged #3? is that even possible? it is in my twisted mind. how about reality?

regarding your exposed images ...
it could have been a mix of light leak, bad exposure.
i don't know to be honest, seeing i wasn't there, and have never
used fuji film or any film that was asa 3000 ...

what you might do is set your electronic camera to asa 3000
and make an exposure WITHOUT a flash and see what
your camera said the exposure was. expose your LF camera
with your instant film at the same settings.
use your camera as your flash meter ( if you don't have a meter )
you should hopefully get an image on the film.

hate to say this, but the learning curve for instant materials is kind of steep too
gettng a couple of tupperware trays for dev + fix + water
will give you instant results without the hassle of wondering
if our instant film is bad or your lens isnt' fast enough + fstop isn't smallenough
and the chemistry + materials might cost less than 4 exposures made with your instant ...
...

good luck !
john

ps. asa 3000 is like surveillance speed, it needs very little light to expose it normally.
a flash, even with a lens stopped down to f45 would be way too much light.
when i did newspaper work years ago, i used a 200ws lumedyne head, and asa 100 tmx
and at 6 feet on a normal day, or normal interior i was stopped down to f 22 at 125thS
i have a feeling your flash was way too hot and your film way too fast ...
get rid of your flash, and shoot in soft low light you might be better off ...

[Dan Fromm]

sorry, the flash to subject distance was around 18". GN30m flash at 1/16th. I tried to set the shutter at the highest speed so that only flash light made the exposure. I must admit, I did not do the maths, being excited about finally getting to do some shooting! After some quick calculations on the back of an envelope, looks like 0.5m (about 18") at F16 with 3000asa film, is equivalent to the settings I made.

You left a little something out. GN30 M ISO 100.

You did your GN calculations correctly, but for ISO 100. With ISO 3000 film you're overexposing by 5 stops. Polaroid film is reversal, with reversal film overexposure makes the finished product very light. And that's what you have.

[JollyGood]

You left a little something out. GN30 M ISO 100.

You did your GN calculations correctly, but for ISO 100. With ISO 3000 film you're overexposing by 5 stops. Polaroid film is reversal, with reversal film overexposure makes the finished product very light. And that's what you have.

http://dpanswers.com/content/genrc_flash_calc.php

I am an idiot! thanks

[JollyGood]

To test x sync
take the back/groundglass off so you can look into the bellows (from the rear) through the lens.

Open the lens wide open (5.6?) and set the shutter to whatever speed you like but test them all when you get the chance.
Fire the shutter with camera and flash pointed at a blank wall and you should see uniform illumination through the lens with no sign of the shutter blades.


edit: I'd put the rayflash aside for now until you make sure everything is kosher.
that thing will probably rob some power so the quide # will no longer apply.

cheers!