PDA

View Full Version : Problem with 8x10 splitter - ideas?



Scott --
13-Jul-2010, 08:49
Hi, all -

Made a splitter from an 8x10 darkslide today. I've made and used these before with no problems; I'm baffled as to what happened today:

http://i531.photobucket.com/albums/dd359/smpsweeps/0009.jpg

http://i531.photobucket.com/albums/dd359/smpsweeps/0008-1.jpg

The holder hasn't ever shown leaks before, and the splitter fits nicely. Ideas what's going on here?

Scott

David Swinnard
13-Jul-2010, 18:30
Is it possible the light trap mechanism where the slide is inserted is somehow "lifted" across the whole width (or at least more than the 1/2 width) when the split slide is inserted?

I don't know how you fabricated the 1/2 slide but years ago when I wanted 1/2 slides for testing I made sure to only remove material back to the edges of the actual "film window" in the holder. This ensured, when the half slide was inserted, a full-width portion was engaging the light trap.

Dave

Scott --
13-Jul-2010, 18:59
Hi, Dave -

Yeah, that's how I made them - the cutout is only in the film gate. It seems clear that the leaking is coming during exposure of each side (contaminating the other side), but I've never had this problem with splitters before. I are, corn-foosed... :eek:

Michael Roberts
14-Jul-2010, 13:18
Scott,
Sure looks like a light leak. What is causing the bright spot in the lower right of the top image, that's not present in the bottom image? Any clue there?

The cause is not obvious to me, either. My first thought was lens flare--that's a mighty shiny truck. Also, I've had a problem a few times removing my dark cloth and having a loose thread catch on one of the pins, pulling the spring back slightly open.

What about the lens and lensboard--anything new or different? Bellows okay?

If you can't find anything obvious wrong with the holder, split slide, camera, bellows, or lens/lensboard, then try shooting a test sheet and see if the problem persists. If not, it must have been a one-off problem.

Ash
14-Jul-2010, 13:21
Coming from a corner, by the shape of it?

Scott --
14-Jul-2010, 13:30
Okay, I setup a test today: Shot one side with the splitter, developed the film and checked for light infiltration to the screened side. It's been raining all day, so I set up a flower, and shot the 16:10 exposure:

http://i531.photobucket.com/albums/dd359/smpsweeps/0010.jpg

Yeah, I have a problem with agreement between the masking on my ground glass and what the splitter is actually doing. But, from this admittedly questionable test, the splitter worked fine. Next test will be shooting it outdoors in daylight to see if it happens again or not. Maybe I pulled the holder out a little when moving the darkslides around...

Michael Roberts
14-Jul-2010, 13:42
Damn, that was a fast test shot--12 min! Must be using one of those rapid developers...:)

Scott --
14-Jul-2010, 13:44
Damn, that was a fast test shot--12 min!

Shot this morning. Just got around to scanning... ;)

Ash, you may be right. I'll try with another holder on the next round of test shots. May take the kids out for a hike tomorrow...

dave_whatever
14-Jul-2010, 13:51
Are you sure on the day in question you didn't just acidentally pull the spring back and entire darkslide unit away from the camera slightly when inserting, or more likely removing, the splitter board? Depending on the strength of the springs on your camera back it's quite easy to di, especially when stood behind the camera.

Scott --
14-Jul-2010, 14:29
Are you sure on the day in question you didn't just acidentally pull the spring back and entire darkslide unit away from the camera slightly when inserting, or more likely removing, the splitter board? Depending on the strength of the springs on your camera back it's quite easy to di, especially when stood behind the camera.

Yeah, Dave - you're likely right. Time for another test, eh? ;)

Scott --
15-Jul-2010, 09:59
Ok, hiked the 8x10, holders, lenses, miscellany, and two kids for a 2.5 round-trip walk to a local waterfall this morning, just to try out the splitter again. Negative's drying. Looks perfect, at least splitter-wise. Posts forthcoming.

Looks like the first test was either a bad holder (today's was a different one) or user error. I'm betting on the latter.

Scott --
15-Jul-2010, 10:48
One of the two I shot today:

http://i531.photobucket.com/albums/dd359/smpsweeps/0012.jpg

Have some markup issues on the ground glass, but the splitter looks fine.

Thanks for the help, everyone!

Robert Hughes
15-Jul-2010, 11:18
One of the two I shot today:
That's a nice, er, half a picture. Where's the other half?

Michael Roberts
15-Jul-2010, 11:56
Robert,
I think the other half is here:
http://www.largeformatphotography.info/forum/showthread.php?p=608274#post608274
:)

Scott --
15-Jul-2010, 12:52
Yeah, that's, er, both halves. :D

Curt
16-Jul-2010, 14:25
Scott, the problem is the Ram, I've got one exactly like yours, it give off bad vibes. OK, I was thinking of mine, it look as good as yours but mine has a lot of miles on it.

I'm a bit confused a bit, what is the camera, is a dark slide used with a cut out of the area to be exposed or are you using wood sliders in the camera back. Sorry for the inquire I'm a little under the weather.

My old cameras have the springs and slots for sliders but I have never used them, It would be nice to see how it goes with your setup. I see that there are slots in both directions, I assume that one is for 4X10 and the other for 5X8 is that correct?

Curt