Convenience… Compendium or Collapsible Lens Hood

[Paul Butzi]

"Well, with the "darkslide" method, you just hold it so that the lens is "shadowed" - I cannot believe that any extra light entering the lens from the "unused" portion of the angle of view would have any effect unless you have a bellows flare problem."

You might be surprised.

Try this: on a day with clear sky, go outside, compose a scene pointing away from the sun.

Under the dark cloth, pop the GG off the camera, and see how much light you can see coming off the bellows. I did it with a Wisner and a 300mm lens so the bellows were extended some, and it was like my own private little discotheque in there.

The bellows in my linhof TK is better, and roomier, and so there's less bellows flare. Still, with a 450mm lens, it's an issue for sure.

Bellows flare is a real problem. Really.

-Paul

[Scott Rosenberg]

so Paul, what do you recommend? are the collapsible rubber shades adequate, or must one use a compendium for an real shading?

[Will Strain]

and while we're on the subject, are there any compendiums anybody can recommend that will fit on a wisner traditional 4x5 (other than the lee ones, which just fit on the lens)?

[Donald Hutton]

Paul

I see the point - but that surely that really only applies to lenses with much greater coverage than necessary (like a 300mm Tessar or the 450 which will both cover 8X10 easily so really are pouring all sorts of extraneous light into the bellows of a 4X5). That said, I have used both quite extensively on 4X5 and have never seen a single sheet ruined by bellows flare. I only shadow the front element when I need to outdoors. I can't believe that I could have just been that "lucky" if it was a real potential problem? I also don't believe that the inside of the bellows on my Ebony are much different to anything else out there in terms of absorbing stray light. I suppose what I'm saying is that bellows flare is a different issue to lens flare - I believe that you can avoid all lens flare with the darkslide shade and I have yet to experience any problems with bellows flare.

[David A. Goldfarb]

You're also getting lots of extra image circle whenever you're shooting in the portrait range or closer. The advantage of a compendium shade is the sort of thing you are much more likely to see when you do a side-by-side test. It might look like you're not losing any contrast due to lens flare or bellows flare until you really do a critical comparison.

[Paul Butzi]

Don-

Yes, clearly bellows flare is going to be a function of how much larger than the film the circle of illumination is.

Several points:
1) For many lenses, the circle of illumination is larger than the manufacturer's quoted image circle size, and the bellows doesn't care if the image is sharp, it's just go to reflect the light all over the place.

2) Bellows flare is more of an issue on cameras with short maximum bellows draw, because as the bellows stretches out, the pleats flatten and thus are less effective 'baffles' and more 'straight tube'.

3) lenses have more coverage than you seem to think. A 150mm Apo-Sironar-N has a image circle of 214mm, so that the image circle when focused at infinity is roughly 2cm out from the *corners* of the film. That's a lot of light whanging around.

Both lens flare and bellows flare are going to be caused by ANY light that hits the lens surface that is not landing on the film (or absorbed by the bellows or the lens elements and mount, or just reflected back out of the camera).

You walk around all the time, looking through your eyes, and you never notice the lens and bellows flare of your eye. But do this - go get a toilet paper tube. Make the inside black. Go outside, and look at some shadow area, and then look at the same area through the tube. Notice the difference?

Unless you've made two exposures of the same scene, one with a properly adjusted compendium and one with no shade at all, you're probably unaware of how much flare will reduce tonal separation in the shadows. I know I was before I happened to notice the bellows flare and ran a test.

Now, all that said, I'm the first to admit that when I had a Lee compendium, I didn't use it. It was too much hassle.

Now that I have two different circular shades (one a spun aluminum one, one one of the telescoping/folding rubber ones) I use them most of the time.

But sometimes, I just use a gobo, like a handy readyload packet or a darkslide, or my hat.

[Donald Hutton]

Well now you have me thinking Paul... and that's a dangerous state of affairs! I am going to have to sacrifice a few hours this week to do some experiments.

[Mark_3632]

Great thread. Is there a catch all kind of compedium hood that might attach to the standard of different types of cameras or are they all brand specific? Or is Lee the only option. I want one for my Sinar F1, and Prinzdorff. Anyone use the Cokin lens shade?

[Scott Rosenberg]

don, please be sure to share your findings with us.