Vented Lens Hood

[CMoore]

What is the purpose of this type of hood.?
Sorry if "vented" is not the right term, but you guys know what i mean.
They look like this...............

Thank You

 

[Pentode]

They are meant for use on rangefinder and viewfinder cameras on which a normal, solid hood would block part of the frame when looking through the viewfinder. They’re actually quite effective.

 

[CMoore]

Sorry...never really used a Rangefinder.
I realize they are not "through the lens" and the viewfinder is off-center of the lens.
Are you saying you actually look through part or all of the Vent/Slat (of the lens hood) when using a Rangefinder type of camera.?
Thanks Again

 

[Pentode]

Yes, that’s exacty right.
You still see it in the frame, but it blocks so little of the viewfinder it doesn’t really get in the way of composing the image.

 

[jimjm]

Some large and long lenses will block part of the view using some rangefinders, and having a hood attached just makes it worse. Vented hoods can make this less of a problem.

 

[CMoore]

I see...Very interesting... Thank You.

 

[Russ - SVP]

Oly RC rangefinder.

 

[AgX]

It is known that some lenses "breath". Those vents enable the necessary air stream.

 

[CMoore]

I realize the need to use it with a Rangefinder.
Is there any "real" likelihood of this style causing a problem on a SLR.?
Is it possible that the vents can also leak enough Light/Sun to cause problems or flares.?
Thank You

 

[Pentode]

Is there any "real" likelihood of this style causing a problem on a SLR.?

None whatsoever. It will work just fine on an SLR.

 

[John Koehrer]

Wonder what it's worth to someone with the RF 1.2?

 

[flatulent1]

And I always thought it was for aerodynamics...

 

[Ko.Fe.]

Wonder what it's worth to someone with the RF 1.2?

I need help to understand your question.

 

[AgX]

I realize the need to use it with a Rangefinder.
Is there any "real" likelihood of this style causing a problem on a SLR.?
Is it possible that the vents can also leak enough Light/Sun to cause problems or flares.?

None whatsoever. It will work just fine on an SLR.

That common lens shades are are not slitted has a reason: to give better shading.

The best lens shade design is not only closed, long, but not vignetting, but also shaped according to aspect ratio. Something rare in still photograhphy, but common in cinematography.

 

[jim10219]

If you're using that style lens hood to close out the surrounding light while pushing the lens up against a pane of glass, like when you're trying to photograph fish at an aquarium without getting reflections in the glass, it can cause a problem. If the sun is directly behind you and shining light through the vent that's reflecting off the front lip of the hood, that can also cause a problem. But those are two rare circumstances.

 

[AgX]

It depends how these slotted shades are designed. It seems most actually do not allow light from the side to enter the lens directly. Those indeed would work like a standard, closed shade. Except for the rare cases Jim just explained above.

But are all those slotted shades that well designed? On many photos of these that is not clearly visible.

Furthermore, if only using them on one lens, with stationary front ring, one could tape all unnecessary sloted parts.

 

[Russ - SVP]

I use them on all of my rangefinders. There is no reason to use them on SLR’s.

 

[Ko.Fe.]

That common lens shades are are not slitted has a reason: to give better shading.

The best lens shade design is not only closed, long, but not vignetting, but also shaped according to aspect ratio. Something rare in still photograhphy, but common in cinematography.

Not so rare among rangefinder lenses. Modern Leica made often have these hoods and third party 3d printed are available.

 

[removed account4]

And I always thought it was for aerodynamics...

funny, i always thought it was so if you were photographing a male or female HOTTIE the lens didn't get over heated...

 

[John Koehrer]

I need help to understand your question.

I don't think there are that many of that lens around and most of them are likely to not have the hood.

 

[MattKing]

Were they not a reference to the design inspiration of DEVO?

 

[removed account4]

you never know matt
https://boingboing.net/2018/07/06/the-real-meaning-behind-devo.html

 

[Ko.Fe.]

I don't think there are that many of that lens around and most of them are likely to not have the hood.

Sorry, but is clear as mud, still. Which lens you are talking about?

RF lenses where made in hundreds of thousands and they are still made for the dark side, due to their compactness.
Many of them are in use and with hoods. Because it helps with flare control.

Vented and rectangular hoods are sold on ebay and from special new style 3-D printing shops.

https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=vented+lens+hood&_sacat=0

https://www.ebay.com/bhp/square-lens-hood

 

[Pentode]

But are all those slotted shades that well designed?

I have a bunch of them for a variety of rangefinders, many of which are cheap Ebay/China knockoffs, and have not noticed any flaws in design. They do what they're supposed to do provided you match the right type of hood to the lens according to focal length.

There is no reason to use them on SLR’s.

Unless, of course, you already own one and it fits on a lens for your SLR, in which case, why not?

funny, i always thought it was so if you were photographing a male or female HOTTIE the lens didn't get over heated...

Ever tuned-in to the core principals of the design!

 

[abruzzi]

Sorry, but is clear as mud, still. Which lens you are talking about?

I think the reference was to the photo in the original post, which according to the printing is for a Canon 50mm f1.2. I don’t know how common a lens it is, or how common the hood is, but I can imagine that kind of original hardware might be hard to find and pricy.