Lens hood and Polarizer

[Reinhold]

Hello everybody - I'm rather sure, this Q has been asked before; but I'm new here, and a beginner with the DSLR, so here it comes (again):

I have just bought af lens hood and a polarizer. Both seems okay, but:

1) should I use them at the same time? It's difficult to turn the polarizer, when the lens hood is on.

2) can I leave the polarizer on all the time? When I auto-focus, the polarizer turns also - what can that do to my pictures?

I will be very happy to get a little advise about the use of the polarizer (when and where) and the lens hood.

sincerely
Johnny

[Colin Southern]

Hi Johnny,

Welcome to CiC - it's great to have you with us.

Polarisers (or "CP" for short) (circular polarisers) are a popular filter - but they have both advantages and dis-advantages.

If you want to minimise glare from such sources as the sun shining on water - or enhance the saturation of vegetation that is being degraded by glare then they're somewhat helpful, but they also have some significant disadvantages such as costing you around 2 stops of light (so shutter speeds need to be lower to compensate and that in turn can accentuate camera shake and subject motion) - with wider-angle lenses you'll get uneven sky - and of course you have the issue of them conflicting with your lens hood (the consequences of which removing it may leave you exposed to flare that the lens hood may have shielded).

So no - you generally wouldn't want to leave one on all the time.

To be honest, I think they're grossly over-rated. I have 2 very expensive ones and they NEVER see the light of day ... I just don't have a need for them (and people tell me that my images seem to come out ok).

[Mike Buckley]

Good questions, Johnny! Welcome to CiC!

You'll likely get some different opinions about whether to leave the lens hood on all of the time. I do because I think it helps protect my lens and camera if I drop them. Though I have no scientific evidence to support that, I did drop my camera once on a concrete floor and I'm convinced that the lens hood, which broke, prevented damage occurring to the more expensive lens.

If you decide not to keep the lens hood on all of the time, at least use it when you might be shooting toward a strong direct light such as a lamp inside your home or the sun when shooting outside. (Though you should never point directly toward the sun for safety reasons unless it is very low in the sky.) The lens hood will minimize or eliminate flare, which will reduce contrast in your image.

You definitely do not want to leave the polarizer on all of the time; use it only when it is advantageous to do so. Use it when you want to reduce or eliminate glare on non-metallic subjects, darken the blue part of the sky, or when you want to use it as a neutral density filter, such as when creating a smooth, creamy effect of water moving in a stream. Otherwise, take the filter off your lens because the filter reduces about 2 stops of light entering the lens. If you're using a wide angle lens and including the sky, be very careful about using the polarizer, as it may cause problems with the sky; you may need to remove it in that situation.

If your auto focus is causing the front element on your lens to turn a lot, focus first and then position your polarizer. Then refocus and release the shutter.

You might want to edit your profile to include your general location so it always displayed to the left of your posts. Some of your questions might be location-specific and knowing your location will make it easier for people to answer questions.

Now that I have seen Colin's excellent post, I'll add that I use a polarizer almost all of the time when I am shooting outdoors; I find it extremely useful.

[Inkanyezi]

You shouldn't have the polariser on always, as often, you would not want the rendition a polariser might give.

The lens hood is mostly a Good Thing. It protects against more than stray light. However, it is difficult to turn the polariser when the hood is on, if the hood does not have provision for access to the polariser. There are such hoods, that have either a hole or a slot, so you can reach it with a finger. You can also prepare your hood to permit access to the polariser.

Mostly, there is no need for cutting off light from down below, so a large hole in the hood, or the lower portion missing completely, would not be a problem. Some hoods have such a hole, and you can open it sufficiently to get access to the rim of the polariser, so you can turn it. Depending on just how the hood sits, the hole needs not be very large. A slot that is just wide enough to let you pass your finger along the knurled ring can do the trick if the hood is very close to the filter. For most petal-shaped hoods for the kit lenses, nothing particular is needed, as it is rather easy to reach the filter anyway. It is primarily with longer lenses and a long hood, that you need either a hole or a slot.

The polariser has two uses. One is to make the sky deeper blue, in the direction perpendicular to the sun, and the other is to eliminate glare from non-metallic surfaces as water, paint, leaves, rock, street paving and other surfaces that might cause glare by reflection. The polariser thus can make a deeper green colour of the leaves. The caveat is that glare might be a positive contribution to the image, so we don't always want to eliminate it.

The polariser can block polarised light, i.e. reflection at an oblique angle from non-metallic surfaces. When the angle is almost straight, the light will not be polarised, it works best at angles somewhere between 20° and 45°.

So the polariser is used occasionally, the lens hood always, except when using built-in flash.

[Colin Southern]

darken the blue part of the sky

I might add that it does this by essentially attenuating the exposure from the polarised portion of the incident light; you can achieve the same thing by dialing in a stop or so of negative EC (exposure compensation) (at the expense of shadow and midtone detail, both of which can easily be restored in post-production) (with the added benefit of not having an uneven sky if a wide-angle lens was used).

eg

[Manfred M]

On the other hand, I rarely remove my polarizer for outdoor shooting and only remove it when it gets darker out and I need the extra stops of light. Removing the reflections from vegetation, less glare on water / glass / other non-metallic surfaces, and more contrasty skies (understanding the limitations of having to be at right angles to the sun and not doing this with a wide angle lens to avoid banding).

Do I use lens hoods? Yes; but generally only in backlit situations (sometimes - my hand is a great sunshade) or when it is raining out. If I need both a lens hood and a polarizer (yes there are some limited situations where that is true), I will set up the polarizer and then pop on the lens hood and get the shots.

[Ady]

I would add my general agreement to the comments already given.

Though I do keep CP filters in my bags because there are a few edge cases though where a CP is a life saver (well a job saver at least). I occasionally find myself shooting through and around glass (and still water or lots of shiny steel) that I don't want reflections off, edge cases I know but with the commercial work I do it crops up, especially in modern business premises. An extreme example was a job in a medical science research facility with spaces completely enclosed in glass that you aren't allowed into as a 'civilian'. Using CP filters allowed me to make the glass walls all but disappear.

Cheers,
Ady

[Reinhold]

Wow - fast answers....I like it! Thank you for your answers - I've allready learned a lot about how to use/not use my CP and lens hood. I'm also beginning to understand, that there really are no rules, as long as one is satisfied with the outcome. And yet, maybe there IS one rule......TAKE PICTURES, and find out how things work.!! ;-).
Never the less - there may be no rules, but I'm sure I'll be back soon with more questions.

[rpcrowe]

Johnny, welcome to CiC...

Using a CPL with a lens hood mounted is often a bit difficult...

Using a CPL with a lens in which the front element rotates is also a bit of a PITA...

In order to rotate the front element of the CPL when it is recessed in a deep hood, it really helps to have long grinch like fingers. However, the fingers don't have to be green



It is relatively easy for me to rotate the front element of my 77mm CPL when mounted on my 17-55mm f/2.8 IS lens with a hood attached. I seem to have room (even without Grinch Fngers) to rotate the front element with the edge of my forefinger.

When I am using a CPL on my 70-200mm f/4L IS lens, I use a generic, round, screw-in lens hood. (top image below). Simply screw the hood into the threads of the CPL front element and rotate the hood to rotate the CPL...



The round filter protects the lens from flare and physical damage. I once fell with the lens hitting the street hood first - hood was toast but, the lens was not damaged a bit!. That hood was the best five dollars I ever spent on photo gear. It saved a lens worth over a thousand dollars...

The round hood also doesnt vignette at any focal length (on my 1.6x cameras) and is a lot more convenient to travel with because of its size.

IMO, the best solution is what Pentax developed. This hood has a sliding door at the bottom which allows you to rotate the CPL.



Some photographers cut a slot in their Nikon or Canon hoods using a Dremel Tool but, this might leave the lens suseptible to flare from below (like when shooting over water). I am surprised that China has not offered copy-cat Canon and Nikon hoods with sliding doors...

My solution to the problem of front element rotating is not to select a lens with a rotating element. Before the 70-200mm f;/4L IS (which does not rotate) was offered by Canon; I came close to purchasing the 70-300mm f/4-5.6 IS lens because I wanted a farly lightweight telephoto lens with IS. However, I decided not to purchase it. One of the reasons for not selecting the lens was because the front element rotated. Unfortunately, most lenses without rotating front elements are the more expensive models.

[Inkanyezi]

I rarely use the polariser, but it's always in my bag and sometimes I find a reason to put it on.

This image is just a snapshot, but I wanted the fish to be visible, so that it can be compared in size to the man standing on the boardwalk.


Tarpon at Bayside, Miami FL

[CemAygun]

Being a newbie myself (I guess I am as green as one can get), I use a small trick with my polarizer: I carry around lightly tinted, polarized shades. I put them on to decide whether I need the filter or not. If like a scene better with the reflections, for instance shooting at the calm morning ocean mirroring the cloud cover, I don't put the filter on. But if the scene looks more defined, more robust to my eye with the shades, I put the polarizer on.

I know it sounds lame, but it helps me

Lens hood is a blessing though. I had it for my old Panasonic and used it religiously. I generally shoot outside, at the beach and white sand beaches can get almost as bad a snow when it comes to stray light...

Unfortunately I don't have one for my NX2000...

[csa mt]

Welcome! Nice to see your first post here! That's a great idea using polarized sunglasses to check out whether you wish to use a polarizer filter.

[Peeshan]

Mostly, there is no need for cutting off light from down below, so a large hole in the hood, or the lower portion missing completely, would not be a problem.

Actually, it can be a problem in winter - the light reflecting on snow can be very strong.

The Pentax lens hood described above is awesome, maybe it would be possible to DIY something equivalent, you could drill a hole on the upper right or left of the hood and then duct-tape the upper side of a piece of bike-tire to close it - ugly but it should work.

edit: actually I'm stupid, you could nicely saw it of and then re-use the part you've taken off instead of bike-tire. And a bit of blue-tack should keep it closed

[CemAygun]

Well I ordered a collapsible rubber hood to be used with my polarizer. From the pictures it looks like you should be able to collapse it to a full retreat, make adjustments to your filter and pop it back up before you take the shot. It will take ages to arrive though (regular post), but when it does, I'll let you guys know if it works as I anticipated.

PS: Thank you "csa mt" for the encouraging first reply!

[csa mt]

You are most welcome! We're very glad to have you join us!

[Manfred M]

When shooting with a polarizer, I frequently use the least expensive lens hood available; my left hand. It's always with me, rarely gets in the way and to date, have never lost it. Just block the light by holding your hand in an appropriate position. If done correctly, often it doubles as a lens support. And adjusting the polarizer is super quick and easy.

I learned that trick in the "old days" when lens hoods were frequently not shipped as part of the lens.

[gorandle]

Easy fix for me was a cheap rubber lens hood threaded front and back. CPL goes on outside, so easy to adjust.

[rpcrowe]

This thread is pretty old... Surveying it, I was surprised that I had answered it years ago (26 April 2013) and I will still abide by that older posting with one recent addition.

When I purchased my Canon 100-400mm f/4.5-5.6L IS ii lens from Adorama, they provided a free package of goodies (actually free - the lens without the package is the exact price as the lens with the package)... Included in this package was a Flex Lens Shade which I promptly put away and forgot about because the Canon hood for that lens incorporates an access door for rotating the CPL. I forgot about the Flex hood... UNTIL... I purchased a set of square filters. The Flex Hood works extremely well to shade a lens that is wearing a square filter.
https://www.adorama.com/flsa001.html
The list price for the Flex hood at Adorama is $39.95 which is pretty steep (after all you can use your hand or hat for that purpose as Manfred stated). However, since I got the Flex hood free, I do use it and I like using it. Your hand/hat is fine for shading a lens when you are tripod mounted however, it can be a bit of a PITA when hand holding a long heavy lens like the 100-400mm f.4.5-5.6L IS ii.