Lens hoods don't really do very much

I have always used a lens hood. I learned, or rather was told, long ago that a hood would cut down on extraneous

 

light hitting the lens and causing veiling flare. Photos would be much crisper especially when taken outdoors in

 

bright sun. I always used a compendium bellows type hood outdoors with large format. Having nothing better to

 

do the other day I decided to use my compendium hood for some photos to see how much better they were

 

compared to photos taken without any lens hood at all. To my chagrin I found that there was no discernible

 

difference between the photos taken with the hood and those taken without. Some examples. (No editing, sharpening etc was done except for resizing):<P>

 

<center>

 

<img src="http://jdainis.com/lensshadepictulip1.jpg"><BR>

No lens hood at all. Sun on upper left in front of camera.<P><BR>

 

<img src="http://jdainis.com/lensshadepiccomp1.jpg"><BR>

With compendium lens hood. (Extended a bit too far so there is vignetting)<P><BR>

 

<img src="http://jdainis.com/lensshadepictulip2.jpg"><BR>

No lens hood. Sun 1/2 frame up and to the right 1/4 frame.<P><BR>

 

<img src="http://jdainis.com/lensshadepiccomp2.jpg"><BR>

With compendium lens hood<P>

</center>

 

You can copy the URL for each photo and blink back and forth with the BACK and FORWARD arrows and the

 

only change you will see is a different leaf position due to wind in some of the trees. Without the hood the sun

was

 

shining on the front of the lens and little dust motes were brightly lit but that seemed to make no difference.<P>

 

If the difference is so imperceptible with this lens shade/hood:<BR><center>

<img src="http://jdainis.com/lensshade_comp.jpg"><P></center>

 

what good are these types of lens shades/hoods?<BR><center>

 

<img src="http://jdainis.com/lensshade_tulip.jpg"></center><P>

 

The coatings of today's lenses apparently are of such superior quality that veiling flare is no longer an issue.

I will

 

continue to use a lens hood if only to protect the lens but I don't think I will worry about it much.

<p>James, try repeating the same shots at night, long exposure if necessary, and use a 100W bulb as the sun. I think you'll see a dramatic difference. </p>

Michael, The first time I saw a compendium lens hood was on a Hasselblad with waist level finder and tripod on a fashion shoot. Perhaps indoors with directional lighting does make a difference.

<blockquote>

<p>"The coatings of today's lenses apparently are of such superior quality that veiling flare is no longer an issue."</p>

</blockquote>

<p>I'll bet someone can produce data to contradict this, but...<br>

...I can't argue based on the photos I've taken. I have far fewer problems with veiling or ghosting flare with even the modest 18-70/3.5-4.5 DX Nikkor than with any other midrange zoom I've used. Takes a lot to produce flare and even then it's not nearly as bad as with the older Canon FD, Olympus, Vivitar Series 1 and other manual focus lenses I'd used.</p>

<p>I still use lens hoods on most lenses in most situations. Just a habit. But unless I can see the sun or other bright light directly in the frame, I seldom see any flare. Even shooting into the light, just moving the angle of the camera very slightly is often enough to move the ghosting flare out of sight.</p>

<p>On the occasions when I actually want flare, or lower contrast from veiling flare, when shooting a backlit subject, I have to use an older lens or an older fixed lens camera.</p>

<p>Once I dropped my lens and the hood saved it...<br>

The hood may or may not prevent from flare.,, In any case, it's better with than without.</p>

<p>I have always used hoods.......looked at them as sort of "Sacred Cows", But your posted images do give me pause....:)</p>

<p>James, I suggested the night test because I suspect the presence of visible flare may be also related to the brightness ratio of light source to subject illumination (among other factors).</p>

<p>I found it necessary to use a hood for night shots, long exposure, which was a real surprise when I encountered it first time; you'd think otherwise. Turns out that what little flare the lens produced is always present under the right conditions, just that bright daylight shots tend to mask its presence. </p>

<p>Here's an example of subtle flare normally not visible. It was shot in 2004 with a Sony DSC-F505V, 3 Megapixel P/S, Carl Zeiss lens, straight out of the camera prior to tweaks. F2.8, 8 seconds exposure. The source of the flare is a 60W incandescent light to camera right, about 30' away. </p>

<p><img src="../users/MichaelChang/Images/DSC00838_s.jpg" alt="" /></p>

<p>Flare</p>

<p><img src="../users/MichaelChang/Images/DSC00838_Flare.jpg" alt="" /></p>

<p>By the way, I've observed the same result with a Nikon 18-70/3.5-4.5 DX lens. </p>

<p>James said:</p>

<blockquote>

<p>The coatings of today's lenses apparently are of such superior quality that veiling flare is no longer an issue. I will continue to use a lens hood if only to protect the lens but I don't think I will worry about it much.</p>

</blockquote>

<p>Anecdotally, I observed similar results upon casual observations myself. I do think modern lens coatings must be infinitely superior to their predecessors for their incredible resistance to flare. However, more important than avoiding flare for me, is maximizing contrast. So in this blind belief that I'm attaining 0.0001% more contrast when using a lens shade, I'll keep using them.</p>

<p>Interestingly enough, I noticed someting odd with my AF DC-Nikkor 105mm f/2.0D lens a few weeks a go. I shot some interior images with an umbrella under controlled lighting, and the images looked razor-sharp. I shot outdoors a few days later under very diffuse daylight, and the contrast and apparent sharpenss dropped considerably. My first thought was (rightly or wrongly), "I need a bellows shade when I shoot with this lens outdoors."</p>

<p>I have two used Mamiya 645 bellows lens shades that I was planning to use with my short Nikon FX primes: AI-S 35mm f/1.4, AI-S 50mm f/1.2, AF-S 50mm f/1.4G, and a DC-Nikkor 105mm f/2.0D. The 645 hood is too small for my DC-Nikkor 105mm, so I'll have to upgrade that to a Lee Filters bellows instead. I was planning to do some tests soon with that 105mm.</p>

<p>I use the collapsible rubber type. Hoya makes some better quality ones than the ones selling on eBay. I work outdoors where I have to do allot of chimping and the hood does work, but it depends allot on the direction of the light. It also depends on the lens. Some lenses are prone to flare while others are not. Indoors the hood prevents stray strobe light from hitting the lens. </p>

<p><img src="http://studio460.com/images/jesseye.jpg" alt="" /><br>

AF DC-Nikkor 105mm f/2.0D<br>

Night interior shot under controlled lighting, using the short, built-in Nikon lens shade.</p>

<p><img src="http://studio460.com/images/court105A.jpg" alt="" /><br>

AF DC-Nikkor 105mm f/2.0D<br />Daylight exterior, available-light only, using the short, built-in Nikon lens shade.</p>

<p>Certainly the difference to the naked eye would appear insignificant. But the rms tables don't lie. Kodak always listed two different resolution numbers for any given film. These are for high and low flare situations, and the high flare "always" resolves less. <br>

Maybe if you tried to enlarge two similarly shot images, the lack of hood would betray itself eventually?</p>

<p>And finally ,hoods look cool. After Ansel Adams was seen with his Hassleblad w/ that square shade. Hasselblad likely had to boost production.</p>

<p>Now, I realize that in the two photos above, it's not an apples-to-apples comparison. But in the interior, she was lit with a 60" umbrella, only just a few feet away, plus a small fill on the left. Now, obviously, the daylight shot has more diffuse light, spraying from all over the place, and less overall contrast is likely to be expected, but I was a bit taken aback by how flat and "soft" the image looked, when compared with interior shot, photographed with the same lens.</p>

<p>It's not really a good test to roll out a couple of shots and say "see, no flare!"</p>

<p>I used to work in camera design and QA at Kodak (24 years worth) and our standard product testing included flare and veiling glare. Part of that testing used a point source of light moved incrementally toward the camera's field of view (dozens of CONTROLLED shots). When things got bad they'd be really bad with visible flare but sometimes it would appear as a more general loss of contrast.</p>

<p>The effect of the built-in lens shade features was measurable and unmistakable.</p>

<p>I think Timothy is on the money by saying it's not exactly a thorough or conclusive test.</p>

<p>Generally though, I think it's good practice to use every means available to ensure the best possible results, even though in some circumstances they may not be 100% necessary. I always use a cable release if I'm shooting on a tripod - in some cases it makes no difference at all due to a fast shutter speed, but it's still a good habit to get into. The same goes for using lens hoods, double checking focus, level, exposure, checking front and back elements for cleanliness, etc. Most of the time it's unnecessary, but every so often it makes a difference and you're grateful you made the effort!</p>

There tends to be less flare when the sun is striking the lens at a very oblique angle (which is probably what happened judging from the shadows in your photos). The closer the sun (or other intense light source) is to the lens axis, the more noticeable the flare becomes.

<p>I don't normally use lens hoods especially as a lot of my shots are taken with ultra wides. In these lenses the hoods are dinky little petals anyway so can't do much and for zooms have to be made to work for the widest angle.</p>

<p>Using large format cameras made me practised in the art of the the ad hoc lens hood. This was usually the slide out of the film holder which is used to shade the lens. So these days especially for wide angle zooms I use the spare hand to shade the lens. Keeping the hand out of shot takes a little practice but you get the best shade effect that way.</p>

<p>For long lenses the lens shade makes more sense. But I still don't tend to use them.</p>

Ralph,

 

Can you explain what you mean that the outdoor is "soft", please?

 

The softness that I see is coming from the dialed defocus. You have the back half of her body, head, and hair defocused

from apparently her ear back. Her chest is behind that thresh-hold as well.

 

Personally, I found the 105 DC's focusing very problematic; auto focus was virtually useless in my experience. I can

blame part of that on my smaller DX viewfinder and my presbyopia, but not all of it.

Two other things on the topic.

 

1) Can some explain the rationale for the shape of the square hood, mentioned above.

 

2) And the shape of the tulip hood, posted by the OP.

 

Intuition tells me that a circular hood to be the most effective or functional.

<p>A square or rectangular shaped hood, simply better represents the area of the actual sensor or film better. The tulip or scalloped hood is for ultra wides. These are used when even an huge, round shade will appear in frame.</p>

<p>When they shoot multi million dollar movies with $100K Panavision cameras. They always use a matte box type (rectangular) shade. Draw your own conclusion.</p>

<p>Try this test. Hold a lens in your hands on a cloudy bright day, and look at the glass while holding it horizontal as if shooting. And now add a hood. There should be large areas of reflection in the glass that will vanish with the hood added. This scattered light is the enemy of both sharpness and contrast. Ansel Adams was a confirmed hood user and also used his hat in addition for added shading.</p>

<p>Bottom line for hobby shooting and fun, leave the hood home. Who cares? But if you're shooting medium format chromes to be scanned and enlarged, use a hood.</p>

<p>It is easy enough to demonstrate the effectiveness of a lens shade with an A/B comparision. Point the camera in a direction in which it gets direct sunlight on the front element, but with the sun well outside the field of view. Look through the viewfinder and use your hand to cast a shadow on the lens. The loss of contrast due to sunlight is clearly visible in the viewfinder.</p>

<p>Some lenses will show this effect more than others, but none, in my experience, are completely immune. It can occur even with a particularly bright patch of sky, which affects photos taken on bright cloudy days, even if the sky is excluded from the image. The effect is more a matter of degree than kind.</p>

<p>Whether you can see these effects in the final images is problematic. If you can see them with your eye, they are present in the image. The effects will be mitigated by post-processing. The claim of "no processing" generally means "hands-off processing", letting the camera and/or software do the deed without specific interaction. Case in point, the OP's sunlit examples have less contrast in scenes with a hood than without. This cannot occur without processing, intentional or not.</p>

<p>Don't imperfections in lens coatings, not to mention the ubiquitous internal dust, also reduce contrast if there's light shining directly on the front element?</p>

<p>Also, I don't use filters, so hoods reduce the chance that I'm going to mar my front elements.</p>

<p>The lens hood is a flag. I don't use them much, but have seen them work in situations where glancing light will strike the front face of the lens assembly glass. As long as you can accept light from the cone that lens is built for, you're good. It's those shallow strikes across the face that'll flare up a photo.</p>

<p>If you've got eight light sources in the studio, maybe it's a time saver to just put a hood on and not fuss as much. My favorite lens hood is a set of barn doors. I really only find them useful near dawn or twilight.</p>

<p>If they tell us to put a big and deep lens hood on the thing, then nobody has to fuss about learning where the light source is, by 3D angle, relative to the camera position. It's a big plastic tube of complaint control, protecting them from our whining when we fail to manage or respond to the light right. We photo nerds are such whiners about equipment that we'll blame any manufacturer for our failure to remove the lens cap, if we can. So, if they tell us we need to slap a big, deep tube on the front of the lens, then we're couching that lens into a situation where it'll perform better. This'll reduce complaints, and improve the reputation of the equipment.</p>

<p>Meanwhile, whether we need a lens hood or not goes back to do we need to flag the light source or not. It's easier to imply that we should look cool and imitate the idealized professional with the latest doodad than it is to teach six million users where the light is coming from. My crabby opinion, anyway.</p>