Protect lens/filter holder for long exposure

[rpagliari]

I do a lot of long exposure with a digital camera and will start soon with LF (4x5).

I usually wrap a scarf around the filter holder with my digital camera. With a LF camera it is a bit trickier because of the cable release. Do you use any particular techniques for covering filter holder and lens?

Also, do I need to worry about protecting the back (I usually do between 4 to 8 minute exposure)?

Thank you,

[Jac@stafford.net]

No filer. No nothing. Relax, enjoy.

[Audii-Dudii]

Also, do I need to worry about protecting the back (I usually do between 4 to 8 minute exposure)?
The answer to your questions is to test whatever setup you end up with and see for yourself what steps you'll need to take to keep the darkness inside the camera.

Also, if you have no prior experience doing long-exposure photography with film, do some research about "reciprocity failure," because your "4 to 8 minute exposure" with a digital camera will need to be multiples longer when exposing film to compensate for the differences in how the two technologies respond to light.

I am primarily a nighttime photographer and wouldn't dream of taking the photos I do with a film camera because compensating for its reciprocity failure will take all the fun out of my outings. :(

[Jac@stafford.net]

The answer to your questions is to test whatever setup you end up with and see for yourself what steps you'll need to take to keep the darkness inside the camera.

Also, if you have no prior experience doing long-exposure photography with film, do some research about "reciprocity failure," because your "4 to 8 minute exposure" with a digital camera will need to be multiples longer when exposing film to compensate for the differences in how the two technologies respond to light.

I am primarily a nighttime photographer and wouldn't dream of taking the photos I do with a film camera because compensating for its reciprocity failure will take all the fun out of my outings. :(

So in summary you can offer nothing to the constituency of this group of large format film photographers. Why post?

[Audii-Dudii]

So in summary you can offer nothing to the constituency of this group of large format film photographers. Why post?

Huh?

I thought I was offering general but constructive comments to somebody who appears to be coming to film photography directly from digital photography and is jumping in at the deep end because of the type of photography he intends to do.

Without knowing more about the specific equipment he plans to use (because judging from his other posts, he's still at the shopping around stage), how would it be possible to answer him any more knowledgeably or specifically than I did? <scratches head>

As for my bona fides, while it's true that I'm primarily photographing with a digital camera these days, it's also a view camera, with which I have a couple of decades of experience.

To that end, I still own a half-dozen film cameras, including a Toyo 8x10, which I used to photograph color transparencies back in the day, even though I'm not presently using any of them.

You might not like my answers, but they're neither wrong nor non-helpful. <shrugs>

[Jim Noel]

Huh?

I thought I was offering general but constructive comments to somebody who appears to be coming to film photography directly from digital photography and is jumping in at the deep end because of the type of photography he intends to do.

Without knowing more about the specific equipment he plans to use (because judging from his other posts, he's still at the shopping around stage), how would it be possible to answer him any more knowledgeably or specifically than I did? <scratches head>

As for my bona fides, while it's true that I'm primarily photographing with a digital camera these days, it's also a view camera, with which I have a couple of decades of experience.

To that end, I still own a half-dozen film cameras, including a Toyo 8x10, which I used to photograph color transparencies back in the day, even though I'm not presently using any of them.

You might not like my answers, but they're neither wrong nor non-helpful. <shrugs>

I thought your comments did more to drive the newcomer away from film than anything else.

[Audii-Dudii]

I thought your comments did more to drive the newcomer away from film than anything else.

If so, that certainly wasn't my intention! :eek:

That said, I don't believe he fully understands what he's biting off here and I was gently, politely trying to clue him in about that.

[LabRat]

You should find a screw in ND filter instead of a filter holder, as some LF lenses are critical that the filter is perfectly aligned in front, because if tilted just a little bit, they can set up severe internal reflections with some types of lenses...

Lenses with a flat element inside seem to double highlights or blob flare under certain conditions when heavy filters are out of alignment...

Steve K

[rpagliari]

hi Audii, thanks for the useful information. As far as digital goes, I have great experience with long exposure.

I've done a lot of research on film (and I've been using 35mm and 6x6 for a year now, mostly street photography) and I think I'm ready for 4x5.
But I did notice, for example, that the lever for cocking the shutter might be a potential source of light leak, and generally speaking lenses are not made for long exposure.

There could also be light leaks coming from the lens board and who knows what else could be an issue. I'm just trying to make sure I won't fail miserably.

It's a good point about the camera that might make a difference. I just ordered a 4x5 viewfinder camera by Stenopeika.

[rpagliari]

You should find a screw in ND filter instead of a filter holder, as some LF lenses are critical that the filter is perfectly aligned in front, because if tilted just a little bit, they can set up severe internal reflections with some types of lenses...

Lenses with a flat element inside seem to double highlights or blob flare under certain conditions when heavy filters are out of alignment...

Steve K

Thanks a lot for the info. Unfortunately, I'm heavily invested into the 100mm Lee system already; so, at least initially, I will give it a try, and use screw in filters later if I get into troubles.

[Audii-Dudii]

hi Audii, thanks for the useful information. As far as digital goes, I have great experience with long exposure.

I've done a lot of research on film (and I've been using 35mm and 6x6 for a year now, mostly street photography) and I think I'm ready for 4x5.
But I did notice, for example, that the lever for cocking the shutter might be a potential source of light leak, and generally speaking lenses are not made for long exposure.

There could also be light leaks coming from the lens board and who knows what else could be an issue. I'm just trying to make sure I won't fail miserably.

My point was that depending on the specific camera / lens / etc. combo you end up buying -- especially because you appear to be looking to buy used equipment -- there are an almost endless number of potential ways that your camera setup can leak light.

The only way you'll know which ones are problematic for you is to test your camera and see what results you get. Then, if you can't figure out why light is leaking in a certain way or from some area, you can post here with some specifics and receive some informed, knowledgeable assistance.

Good on you for thinking ahead, though, and good luck with your adventure!

[rpagliari]

You should find a screw in ND filter instead of a filter holder, as some LF lenses are critical that the filter is perfectly aligned in front, because if tilted just a little bit, they can set up severe internal reflections with some types of lenses...

Lenses with a flat element inside seem to double highlights or blob flare under certain conditions when heavy filters are out of alignment...

Steve K

Could you possibly elaborate on this? For example what do you mean by perfectly aligned?

I can't see the problem unless the filter holder is damaged mechanically.

I believe the flare is mostly due to light leaks, at least in my experience, which is why I use a hood for the filter and wrap a scarf around it.

[Bob Salomon]

Could you possibly elaborate on this? For example what do you mean by perfectly aligned?

I can't see the problem unless the filter holder is damaged mechanically.

I believe the flare is mostly due to light leaks, at least in my experience, which is why I use a hood for the filter and wrap a scarf around it.

A filter is actually also a lens but one of extremely long focal length that would be measured in meters. The best filters are extremely flat so they won’t effect resolution. It is imperative for a filter to be parallel to the lens. That is why holders are not the best choice. Screw in or bayonet or magnetic mounts are far better.

[6x6TLL]

Tangential to this, in regards to protecting the lens, is a UV/skylight filter recommended? Years and years ago when first learning photography, I was taught to always have one mounted, to protect the front element from damage, and that a good filter would not affect sharpness, contrast or resolution.

Is there any reason that wouldn't also be the case for LF today?

[Dan Fromm]

Could you possibly elaborate on this? For example what do you mean by perfectly aligned?

I can't see the problem unless the filter holder is damaged mechanically.

I believe the flare is mostly due to light leaks, at least in my experience, which is why I use a hood for the filter and wrap a scarf around it.

You are mistaken. Flare is due to internal reflections between elements in the lens. LF photographers don't use zoom lenses at all, let alone high ratio zooms so we rarely see any bright flare spots that are reflections of the diaphragm, let alone the long strings of such spots that some zooms produce when the sun is in the frame or near its edge. The typical LF lens doesn't have that many elements, and this helps cut down on veiling flare even with uncoated lenses.

Lens hoods reduce flare by eliminating non-image forming light. Many LF photographers use compendium hoods, bellows whose rear surrounds the lens (with huge gaps, the bellows are square, the lens is round) and extend a variable distance in front of the lens. We set the compendium's length so that it just doesn't cause mechanical vignetting.

LF cameras by and large don't suffer light leaks. When they do, the usual sources are pinholes in the bellows and failure to seat the film holder in the back. Less common causes are failure of the front standard's light trap, failure to cover the hole for a shutter anti-rotation pin in the front standard.

You've been asking about center filters for w/a lenses. These all screw in. Filters, such as the NDs you're going to need, that attach to them also screw in. When the filters are screwed properly in place -- not cross-threaded -- light leaks through the threads are not a problem. And if the filters are well made and haven't been horribly abused, screwing them in guarantees that their surfaces will be perpendicular to the lens' axis. Ain't no gaps or wiggle room.

Y'know, we were all born naked and ignorant. We've had to learn a lot, including to wear clothes most of the time. OP, you really should buy a book on LF photography and read it, you'll learn more that way than from a string of questions and short answers, not all very good. The list mentions a couple or three good ones and suggest where to buy them. Do yourself a favor, ...

[Bob Salomon]

Tangential to this, in regards to protecting the lens, is a UV/skylight filter recommended? Years and years ago when first learning photography, I was taught to always have one mounted, to protect the front element from damage, and that a good filter would not affect sharpness, contrast or resolution.

Is there any reason that wouldn't also be the case for LF today?

Yes, if you use low end stuff.

[rdeloe]

I do a lot of long exposure with a digital camera and will start soon with LF (4x5).
Also, do I need to worry about protecting the back (I usually do between 4 to 8 minute exposure)?


If everything is in order you shouldn't have to worry about light leaks from pinholes in the bellows, leaks through the back, etc. However, if your gear is old and heavily used you should probably check. My current camera had a new bellows put on it, and they used a clear glue which let some light in where the bellows glued to the metal frame; that was one source of light. More light came in via leaks around the light seals between the bellows frame and the camera; the original seals were compressed due to age and the bellows frame was a bit bent.

These are fixable problems, but you need to find them. My technique is pretty simple. Do you have a spare lens board, ideally Copal 0? Or a lens in a Copal 0 board that you can temporarily dismount from the board? You need to replace the lens with a light source. I had an old clamp lamp for incandescent bulbs. Incandescent bulbs are too hot so I used a nice cool LED "bulb". Mount the lamp in the board, put the camera on your tripod, mount the board in the camera (making sure to tape around the socket so there are no light leaks), insert a film holder, pull your bellows out to max extension, and park yourself and your camera in a totally dark room. Wait 15 minutes if you can so your eyes adapt, and then turn on the light. Crawl around your camera looking at it from as many angles and directions as you can. If you see any light, note where it's coming from so you can do repairs (a whole other subject).

When they're shooting, some people seem to like covering the whole camera with their dark cloth for extra protection. That's not my practice but everyone has their preferred approach.

[Doremus Scudder]

hi Audii, thanks for the useful information. As far as digital goes, I have great experience with long exposure.

I've done a lot of research on film (and I've been using 35mm and 6x6 for a year now, mostly street photography) and I think I'm ready for 4x5.
But I did notice, for example, that the lever for cocking the shutter might be a potential source of light leak, and generally speaking lenses are not made for long exposure.

There could also be light leaks coming from the lens board and who knows what else could be an issue. I'm just trying to make sure I won't fail miserably.

It's a good point about the camera that might make a difference. I just ordered a 4x5 viewfinder camera by Stenopeika.

No, no and no.

Lenses and shutters are light tight. LF lenses are fine with long exposures, and, unless your equipment is defective, your lensboard won't leak light either.

The biggest problem you will likely have in that regard is stray light getting in behind the filters in your holder and reflecting around. That's why Dan and others here recommended screw-in filters (no way for stray light to get in). Lee makes a nice hood... maybe that will solve your problem.

Really, I see no insurmountable problem using the Lee system as long as you realize that you'll have to protect the filters from stray light somehow if that looks like it might be a problem. Use a hood, wrap your scarf around it, whatever; it's not rocket science.

Do read up on reciprocity failure and get yourself the charts for the films you intend to use. With many films, a two-minute exposure on the meter needs to be lengthened to 20 minutes or more. An eight minute exposure on the meter might need an hour or more.

FWIW, I've done this a lot, i.e., shot 20-120 minute (and longer) exposures with black-and-white film and a view camera. No light leaks, even though I usually don't use a lens hood (I do use screw-in filters). And, no problems with exposure once I tested my reciprocity failure and made my own tables. Once exposures get into the minutes with film, it's really hard to overexpose, since doubling the time plus more reciprocity correction (which may result in tripling or quadrupling the time) only adds an extra stop exposure. Err on the side of too long to start with.

Best,

Doremus

[Dan Fromm]

Doremus, the OP has, in other threads, stated that he needs to use a center filter on a wide angle lens with an ND filter to allow very long exposures. I'm not sure that the Lee system is compatible with a center filter. Do you know? Me, I never touch the stuff..

[6x6TLL]

Yes, if you use low end stuff.

Yes it would be a problem, or yes it's recommended to use a UV filter?

I'm using a Rodenstock APO Sironar-S 210mm f/5.6.

[Bob Salomon]

Yes it would be a problem, or yes it's recommended to use a UV filter?

I'm using a Rodenstock APO Sironar-S 210mm f/5.6.

You will have no problem with a quality filter. If you shoot color you want a CR1.5. If B&W and color then the UV. Look for a Rodenstock Black line or a Heliopan MC one.

[pepeguitarra]

... generally speaking lenses are not made for long exposure. ...

I am not sure this is accurate. How come they shutters have a B and a T in the speed selector?

[Doremus Scudder]

Doremus, the OP has, in other threads, stated that he needs to use a center filter on a wide angle lens with an ND filter to allow very long exposures. I'm not sure that the Lee system is compatible with a center filter. Do you know? Me, I never touch the stuff..

Dan,

Of course, the center filter would then have to be screwed on to the lens and whatever filter system that was added on would have to be large enough to not vignette. Not impossible, but I don't know the Lee system well either, or which size (if there are even sizes...) that the OP has.

If the OP really needs a center filter and then wants to use screw in filters on top of that, he may be limited to just one more (thin) filter.

From what I've been reading on his other threads, he doesn't really have a good handle on what he wants/needs yet. He'll have to deal with the learning curve. He may find he doesn't really need a center filter and that his metered 8-minute exposure really needs an hour...

Best,

Doremus

[minh0204]

If reflection is your concern, look up "Benro Light Tent Hood Cover". A focusing cloth covering the back of the camera and the bellows is also prudent to protect against light leak entering the dark slide.