Hi, I'm concern, as a beginner, about vignetting. Whith a sunshade on my lens, does vignetting occur sooner when you apply swings, tilts or shifts? How to avoid it? Should I stop down, until I could se all the shutter blades through the corners of the ground glass? Help! Thank's to all of you. Daniel Luu Van Lang

-- Daniel Luu Van Lang (daniel.luu@worldonline.fr), December 25, 2001

Answers

You don't use lens hoods with vieww cameras. They use Compendiums, Proper compendiums can not vignette if properly used.

-- Bob Salomon (bob@hpmarketingcorp.com), December 25, 2001.

No amount of tilting or swinging at the rear will change the relationship of the shade to the front of the lens. The thing you must keep in mind is that if the lens has coverage beyond what you can see when the camera is neutral, raising or dropping the front or rear, shifting either, or swinging or tilting the front can move the "hidden" portion of the lens projection into view where, if the shade is too long for the lens' angle of acceptance, you may very well see vignetting.

The simplest sunshade is your hat or a piece of black cardstock that you carry with you into the field. If you stand off to the side of your camera and hold the card or hat in such a way as to block any direct rays of sun from striking the lens (you can observe this) you will realize at least the most important value of a sunshade. One further question is whether there is any additional gain from having a shade completely surround the lens at all times. Technically, if a lens has flare, you should be able to help increase contrast by preventing any light that has nothing to do with the subject from striking that lens. Here, an adjustable shade or compendium would be of value. The only caviat is that you must carefully calibrate such a shade so you know exactly how to adjust it for each lens you use or you could experience vignetting.

-- Robert A. Zeichner (info@razeichner.com), December 25, 2001.

No lens hoods with large format??? Guess I've been doing it wrong for over 30 years.

Yes Daniel, the cut out corners are used to check for vignetting.

-- Daev Richhart (pritprat@erinet.com), December 25, 2001.

Well Daev you're lucky that Bob was around to set you straight. If you ask nicely maybe he can do something about that first name of yours.

-- Wayne DeWitt (wdewitt@snip.net), December 25, 2001.

Daniel,

Yes, it is in fact not possible to make a large format photograph with a traditional lens shade. You must use a compendium shade. To get one, simply send a whole lot of money to hpmarketingcorp.com. Without one of these very important items, your pictures will be very ugly and you will hate them, as will other people. Thankfully, hpmarketing.com is here to make your pictures beautiful. For a price.

-- Erik Ryberg (ryberg@seanet.com), December 25, 2001.

"To get one, simply send a whole lot of money to hpmarketingcorp.com."

Once again you don't send us money. You send us requests for brochurtes.

We sell to camera stores not individuals.

Complicated Huh?

-- Bob Salomon (bob@hpmarketingcorp.com), December 25, 2001.

To help check if you will get vignetting or not, after you have done all your corrective movements, peer through the "cut out" corners of the ground glass. If you don't see the lens opening... you will get vignetting. Choose a different lens shade or readjust your compendium.

-- Scott Walton (scotlynn@shore.net), December 26, 2001.

In an apparent effort to be completely unhelpful, Bob has overstated the case. You can use lens hoods with large format lenses -I do it all the time - but they do present the risk of vignetting with front standard movements. The easy way to check is, as you obviously already know, to look at the lens opering through the corners of the ground glass. Start with the aperture wide open and gradually stop down until you no longer see a football shape. The other thing to be aware of is that using your hand or a dark slide or a hat as a substitute for a lens hood often won't work. Tose things will work fine in a situation where the problem is direct sunlight striking the lens. But that isn't the situation in which you most need a lens hood or shade. The time when you really need a hood or shade is in bright diffused light, when non-image forming light is striking the lens from all directions. People don't spend a lot of money on hoods or shades because they're ignorant of the fact that they can use their hand to shield the lens from direct sunlight. They buy hoods or shades because there are many situations in which your hand or a dark slide or something similar won't work.

-- Brian Ellis (bellis60@earthlink.net), December 26, 2001.

What is a compendium?

A compendium is a fully adjustable bag or bellows that attaches to the camera standard (not the lens) that is adjustable so that what ever move you do - front or back - it can be adjusted so that it does not intrude into the image area. Being adjustable means not only for position but also for length. And frequently compaendiums come with or offer masking blades to restrict any oblique light. A proper compendium will have an opening the same size as the film in use (or proportional to it with masks) and an extension equal to the lenght of the bellows of the camera when the image is in focus. Meeting these conditions any light that does not directly strike the film to make the exposure is blocked from hitting the lens surface so flare is reduced and sharpness is enhanced due to better contrast.

A lens hood can not do what a compendium does and very few large format camera manufacturers sell lens hoods (even Linhof who has their drop-in filter hood set does not recommend its' use in lieu of a compendium.

Yes for you outdoor people it adds weight, bulk and setup time and Ansel didn't use one. But it works better then cardboard, hats, hoods and hands. It is repeatable and easy to use once you get use to it and some increase your filtering options with holders behind the compendium.

-- Bob Salomon (bob@hpmarketingcorp.com), December 26, 2001.

Does anyone else enjoy watching people who can't take a joke become defensive?

-- Chad Jarvis (cjarvis@nas.edu), December 26, 2001.

"Hi, I'm concern, as a beginner, about vignetting."

How does he know your jokng?

Or should he not learn the options and the best way of doing things? Should he want to.

Apparently you can tell the difference.

But that makes for a poor reference source.

-- Bob Salomon (bob@hpmarketingcorp.com), December 26, 2001.

Do I detect a sense of humor trying to ooze its way out of a pore, Bob? :^D

-- Chad Jarvis (cjarvis@nas.edu), December 26, 2001.

No. Just trying to explain to someone who claims he is new to the medium. Apparently some would rather he remain ignorant. But then you probably do not get phone calls from people at work who read what is said, to your mind, as a joke who then believes it.

You probably also don't get the calls from disappointed users who lose shots due to a "joke".

-- Bob Salomon (bob@hpmarketingcorp.com), December 26, 2001.

Hi Daniel

Thes theme is like religion every site has his pros and cons! I work only with lens hoods since almost 20 years, but I do it like this: When I get a new lens then I take the pola back and start my testing against a white wall till I find a hood thad is exactly perfect for thad lens without vignetting. Because I then take the lens to a shift position in wich she starts to vignetting then a take the hood on and it should only take the darker outher 2-3 mm away from the lens covering and then you have the best for thad lens better then any quarter lens compendium and then I write it on the hood for wich lens it fits and you d`ont need the time for ajusting a compendium in the cold winter etc. In windy condition is a compendium not so good also because the wind has more power if something is larger! So it is not always easy to find the right hood but meanwile I have one to every lens that fits! Good light to all!

-- Armin Seeholzer (armin.seeholzer@smile.ch), December 27, 2001.