Actually quite interestingly, all the light leaks occur on the opposite edge to the one with the ridges in, which puts them at the top of the film holder near where you insert and remove the dark slide as i'm sure thats how he'd inserted them, holding onto the notched ends and inserting the other end. Whether that means the dark slide whole itself or the meeting of the holder with the camera at that point it at least makes some consistent sense.
It is also recommended to insert the dark slide as "square" as possible to engage the light trap inside the holder uniformly. Starting with an edge of the dark slide and then squaring it as you continue WILL allow light to come into the film area past the light trap around the dark slide if there is light available to mess with you. I also find myself squeezing the rear standard against the camera with a holder in place to make sure that the insertion of the dark slide does not unintentionally cause the rear standard to open up. When you are inserting a long 7x17 or 8x20 dark slide this is more of an issue than with 4x5 but good habits in your shooting routine should be consistent with any LF format you load up.Originally Posted by jimbobuk
Cheers!
Thanks Michael for your long explanation of the handling technik. I really appreaciate your realism with the use of eventual 6x9 format! In fact, I was often thinking of making an alternative for ULF field camera that would be windproof - simply a ULF P&S used on a tripod. The only reason I did not build it is the dimension of it - although easy to make, the camera would need a case surely heavier than the camera itself.
This is exactly what happened to me some years ago on a visit to the Great Sand Dunes in Colorado. I was working with a fairly new 5X7 camera and Fidelity holders that had not previously given me any trouble. However, for some reason the bellows developed a small pinhole that caused a light leak that was not visible on the ground glass. Because of the high winds at the location I decided to not cover the bellows. The result was that some 40+ negatives I made over a three day period have significant fogging from the pinhole in the bellows at the top right, about ten pleats from the camera back. Had I covered most of the bellows with the dark cloth, as I typically do, the damage from the light leak would have been avoided.
Sandy
Last edited by sanking; 17-Sep-2006 at 11:57.
I now keep my 7 x 17 holders in seperate 'bags/pouch'? I had my wife sow together some 'blackout' cloth/material and attach some velcro. I carry my holders in an individual 'bag'. It fits nicely.
When I remove the holder in the direct sun, I do my best to block the sun with my shadow, or use the dark cloth to shield the holder. Again, its not an issue with my 4 x 5 or 8 x 10 but it is with 7 x 17 holders.
Modern plastic holders have design features which make them virtually light tight even in direct sun. This is not true of most wooden film holders, whatever the size and age. The opening flap end is a source of possible light entry, by reflection, with virtually every wood holder I have seen. If you load these holders with film and leave them in bright light long enough there will be some fogging of the film, starting at the corners. A few designs have tried to eliminate this problem. De Busch ULF film holders, for example, used a locking mechnism that involved removing the entire end of the holder. The deign eliminated the problem, but these holders were very hard to load so the solution was worse than the problem. Great Bassin holders eliminated the opening flap and you loaded the film by bending it and shoving it under the loading rails. This worked well for 5X12 holders but 7X17 and 12X20 film was very hard to load with this design, and there was the risk of stress knicks on the film.
To avoid fogging at the flap end it is good practice to carry the holders in light tight envelopes of some kind and remove them from the envelopes only for the shortest period of time needed to insert in the camera back and then remove and return to the envelope.
Sandy King
Re: Keeping the focusing hood whilst making an exposure
I have some 5x12 holders that I bought new in June 2006 and it seems that they have light leaks at the flap end of the holder. I have been shooting with my darkcloth covering these holders and still I am getting light leaks. I have finished unloading the last of them and will be setting up the camera in a darkened room and will be trying the flashlight test to see if the leak is due to how the holder fits in the camera back, just to be sure there's not something wrong there.
I looked at my 4x5 holders recently and compared the flap design to that of the wooden holders and it seems superior in that it prevents light leaks from coming in at the flap edge. I find it aggravating that my new 5x12 wooden holders are not leak proof. For what they cost, they should be.
By the way, when you guys are shooting verticals with your ULF, how do you keep the flap ends covered?
Last edited by Diane Maher; 17-Sep-2006 at 15:31.
There are things that can be done with plastic injection molding with 4x5, 5x7 and even 8x10 holders that simply cannot be replicated in wooden holders. Yes, wooden holders in 5x12 and ULF sizes are rather expensive, but let's not forget that these are are custom made products of some serious complexity and dimensional criteria particularly in the interior. That said, there are a couple of things that you can do to eliminate light leaks eminating from the flap end. First is to use some tape and mask off about 2" of the inside of the inside of the flap and the holder where the flap resides with flat black spray paint. I would add - a very thin layer of the black paint so you do not mess up the tolerances that reside in this area. That way if some stay light entered this area it would not be able to bouce around and get to the sheet film.
We already covered the second component of avoiding light leaks - a dark cloth over the camera.
To answer your questions about the verticle, if your camera facilitates pullng the dark cloth down then you are home free. If it does not then you need to either have a large enought cloth to accept the verticle proportions or go through the elastic hole with the BTZS cloth as I described above.
Cheers!
Jim,
I should probably clarify my earlier comments.
I remove the cloth when making exposures 90 percent of the time. Michael mentioned a couple more situations where I would leave it in place.
When working in windy conditions where objects in the scene can move (such as flowers, grass and branches), I might have to wait a considerable time before the objects stop moving, which would expose the film holder to sunlight for an excessive time. In that case I'd leave the cloth in place. When the subject isn't going anywhere (rocks, desert), I'd probably remove the cloth, make my series of exposures and move on.
If I were concerned about the fabric causing the camera to wiggle in the wind, minimizing the surface area in the manner Michael suggested (stuffing it under belows) works, as does wrapping around the tripod legs and securing it with a small bungy.
With the model camera you are using and the cloth size you have, you should easily be able to leave it in place on the camera while making an exposure, if you choose.
The panoramic cameras described here are more challenging, since the dark slide is so much longer, which I observed first-hand at the View Camera Conference in June. As are result, I am testing the performance of a special sleeve for ULF users that would permit pulling even these long slides.
But for you, the only time it would be challenging to pull the slide with the cloth in place would be the situation I described earlier (film holder in vertical orientation with the dark slide being pulled upward). In all other cases, there is room within the trunk of the focusing cloth to pull the slide. This can be accomplished by feel without your head in the jacket, or, if you choose, you can put your head in the trunk to see what is going on. Just remember, the sleeves are intended to be accessed from the outside in like you were using a changing bag.
In horizontal orientation, it can be done by shifting the fabric of the trunk to one side or other, or you can also pull the slide into, or through one of the sleeves, which still keeps the sunlight from falling directly on the film holder. If the pull is downward, the natural hang of the fabric provides space to pull into.
With the film holder facing upward, you would need to be a little more careful. If you leave the dark slide in the film holder when making an exposure, (some people favor pulling it completely to use as a lens shade), you would need to make sure the slide is pulled sufficiently to clear the film path. Secondly, you need to make sure the weight of the fabric pushing on the dark slide doesn't push it back down into the film path, or cause a separation between the film holder and the camera back. By pulling the dark slide out completely, this problem is minimized, but you'll probably have to practice in the daylight a bit to learn to feel for the slot and easily slide it back in.
FWIW, the types of light leaks I've encountered are as follows:
1. Roll film holder with no real light trap. I pulled the dark slide out completely and light got in through the empty slot. Poor design. I compensate now by leaving the dark slide in the holder, pulling it only as far as necessary to clear the film path. If it is windy, I either shield the dark slide with my body to prevent wind from buffeting it, or I pull it completely and leave the cloth in place as described earlier. The sleeve of the focusing cloth permits me to access the darkened environment to get at the film advance (though this is even possible to do through by manipulating the control knob through the fabric).
2. Same roll film holder, dark slide slipped a bit in transport and light got in through the window where the film is exposed. Again poor design. No lock to prevent the slide from working its way out. I now tape the slide handle in place to keep it from slipping inadvertently.
3. A more challenging leak to diagnose ocurred when I installed a spirit level in the flash shoe on the top of the rear standard. It took some time to determine that when oriented vertically, the film holder was making contact with the edge of the spirit level which created a gap between the film holder and camera back.
Aside from that troublesome roll film holder, I now also work exclusively with Fuji Quikload in a Kodak Readyload holder, so have not had to deal with the issues of loading film, faulty light traps, etc.
Anyway, lots of good advice in this thread. You'll figure it out. ;-)
Definitely.. thanks a lot guys.. i yearned to take some more test shots this weekend but it just didn't pan out that way... it will be happening this week(end) so i'll try to take in all your tips... i will definitely be trying to operate whilst keeping the jacket on, should be ok.. though i guess actually loading the dark slide behind the ground glass could be tricky so i may have to take the hood off for this operation and then put it back on to pull the slide.. we'll see.. practice, practice, practice.
I just hope there isn't something fundamentally wrong with the setup.
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