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About Lens Hoods IMPORTANT!
Posted By: MightyMike, 01-19-2009, 12:49 PM

I have often said that i hate my FA50mm F1.4, sure its a sharp lens at F4.0, some say even at F2.8 but when i want the speed the sharpness
just isn't there, in fact the only fast lens i have that doesn't really suffer a lot from low sharpness wide open is my FA35mm F2.0...

In the case of the FA50, its all about low contrast, same goes for the F50 F1.7 and Sigma 24mm F1.8... and a little bit on the FA77mm F1.8 Ltd...
I know a hood is important for getting rid of stray unwanted light, but you really never no how important it is until you have a bad case of low
contrast for a given lens and you try a lens hood on it. in a personal review of the Sigma 24mm F1.8 someone wrote online they made a really
interesting point, The film (FF) lenses come with a hood that blocks stray light for the FOV related to full frame, however on a crop sensor the
hood needs to be 1.5 times longer to get the greatest benefit, he said he used his Sigma 70-200 F2.8 hood on his 24mm F1.8 without vignetting
and with far better contrast... the other thing we all should understand is that zoom lenses hoods are only good for the widest FOV...

with this in mind i picked up a lens hood off ebay said to be good for 37-90mm ore something like that, its a 49mm thread and its about 37mm
long and 60mm in diameter (it came with a 58mm lens hood)... the hood is longer then the built in hood of the 77Ltd too by about 1.3 times.

here are some of my conclusive test to confirm how much a lens hood helps

Testing back light glare 50mm F1.4 @ F1.4, F2.0, F2.8
what the test looked like


100% crops description written on photo







You can clearly see a marked improvement in contrast and overall sharpness

Now here is one test for the 77mm F1.8 at F1.8, no hood, built in hood, new hood

what the test looked like


100% crops


Look at the contrast in the text and the effect of purple ringing on the black dots

I hope this is clear for everyone now that the right lens hood is rather quite important to improve lens performance especially on fast
primes... now the next thing i have to look for is a larger hood to fit my 24mm F1.8

Last edited by Buddha Jones; 01-21-2009 at 06:01 PM. Reason: Made the 100% crops manageable.
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01-10-2015, 09:40 PM   #46
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This is such good information, and there's so many new members (and users) that I believe a bump is a good idea...

04-11-2018, 08:27 PM   #47
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One little trick I've discovered on my FA501.4 is taking the rubber expanding hood that I bought for it and then screwing the tiny little metal hood that comes w/my DA40mm limited prime into the filter threads of the rubber hood (making a double-hood) works really well w/o viginetting! The inner hood is close to the front element and blocks more centralized stray light that can make it thru the larger outer one, whereas the outer one blocks more pherphral light. It also allows me to collapse the rubber hood and pocket the lens w/o the cap.
04-13-2018, 05:55 AM   #48
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I would say that results are pretty clear. I should use my hoods more frequently
04-13-2018, 07:57 AM   #49
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I always use hoods. Dates back to the 1960's when they were essential to reduce flare on early lens coatings (or absence of ...). First Pentax was the first model (1, 1/2, 1/5, 1/10 etc.) with a 55 mm f/2.2 preset lens. One of the nicest outdoor portraits I have ever taken -- I really should find it in my cubic meter of slides -- is a lovely artist in Stanley Park in Vancouver, BC sketching in the shade of a tree. The glow of the early lens made the image jump out. Hoods don't make much difference when it is the subject that is lit up by sun on the sketch pad, and it works here. Doesn't work everywhere, though.

04-13-2018, 08:53 AM   #50
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Good point, well demonstrated.
08-25-2018, 11:44 AM   #51
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I use hood to avoid flares. It will really help me.
08-27-2018, 07:03 AM   #52
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Can't argue with those results, nice work.
08-28-2018, 11:31 AM   #53
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I am big on using hoods pretty much all the time, but to be honest, until I saw your photo samples, I would have never guessed that it would make THAT much difference.

Time to test my lenses with various hoods and make notes.

08-29-2018, 02:07 AM   #54
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Hi all,
really interesting, I learned something.
And that's why this lens is really good for me, I've a hood !
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08-31-2018, 10:35 AM   #55
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I have a "new" F50/1.7, which has a deeply recessed front element, so people commonly say that it doesn't need a hood. I ran some controlled tripod tests, indoors and out yesterday with 1) no hood 2) a square clip on hood that was sitting around and 3) a FF "normal" metal screw in hood that was on another lens. I'd say that results were inconclusive.

I feel like I used to have a pretty deep telephoto hood in this thread size and it would be interesting to test that, but I think I passed it on when someone bought that lens.

What I did notice is that my lens under-exposes (using Tav mode) at 1.7 and to a lessor degree at 1/2 stops leading up to 3.5. I need to do more testing on that and try different exposure modes and settings. I think I should test another lens the same way to see if the same is true for it/them or if this is unique to this lens. Not sure if it relates to the hood or not. But anyway, of the hood effects contrast as the tests in this thread indicated, it was much more subtle on the F50/1.7 lens. Once I normalize exposure, I'll be able to better tell.

Last edited by troika; 08-31-2018 at 10:44 AM.
09-02-2018, 04:52 PM   #56
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So... I could look at lengthening the hoods for my full frame lenses, or I could just get a full frame camera???

That's food for thought....
09-03-2018, 07:57 AM   #57
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QuoteOriginally posted by troika Quote
What I did notice is that my lens under-exposes (using Tav mode) at 1.7 and to a lessor degree at 1/2 stops leading up to 3.5. I need to do more testing on that and try different exposure modes and settings. I think I should test another lens the same way to see if the same is true for it/them or if this is unique to this lens. Not sure if it relats to the hood or not. But anyway, of the hood effects contrast as the tests in this thread indicated, it was much more subtle on the F50/1.7 lens. Once I normalize exposure, I'll be able to better tell.
I would put the lens on the camera on a tripod in a place where the lighting will be constant, and then do a series of images in manual mode. Set the camera to f/8, use the green button to set a mid range shutter speed, and then just change aperture and shutter speed manually for the full range of apertures.

f/8@1/50
f/5.6@1/100
f/4@1/200
f/2.8@1/400
f/2@1/800
f/1.4@1/1600

etc.
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