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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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01-19-2009, 04:39 PM   #16
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All depends on the reason for shooting. If you want those dreamy portraits then the low contrast, high field curvature and edge falloff of the various 50/1.4s all help to that end. Take a look at the numerous examples of such in our User Photo Gallery.

Jack

01-19-2009, 05:06 PM   #17
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There we have it, incontrovertible proof of the benefits of using a lens hood.
Thanks MightyMike.

BTW I trust there were no filters on your lenses when you did your tests as that could further have an effect on the image degradation.
01-19-2009, 05:22 PM   #18
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well you have inspired me to go and buy a hoya 3 position rubber hood for my 50mm, very good comparison

thanks!
01-19-2009, 05:40 PM   #19
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QuoteOriginally posted by Gooshin Quote
until you get vignetting, there is no such thing as too much hood!

Amen, brother! Be careful, though. Don't do what I did. I put a longer hood on my 35-105mm when I started using it with my K10D, but I forgot to change back to my wider hood when I used that lens on my LX. I ended up with a number of slides that had vignetting.

01-19-2009, 05:46 PM   #20
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It should be easy to extend current hoods with a rolled up piece of black hobby foam from "Wallyworld" wrapped around the current metal or plastic hood and attached with velcro or even a rubber band.
01-19-2009, 05:56 PM   #21
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QuoteOriginally posted by MightyMike Quote
(snip) here are some of my conclusive test to confirm how much a lens hood helps (snip)

I'm a bit suspicious of your results. Based on the shadows in your images, the primary light source in the room appears to be the window directly behind the remote. Therefore, most of the light in the room really isn't coming from a direction which would be impacted by a lens hood which obviously blocks light only from the sides. While I cannot explain the differences in your images, I also cannot explain how a lens hood would be all that effective in this particular lighting environment. That conflict suggests this needs further research in a controlled environment, certainly before the word "conclusive" is used.

stewart
01-19-2009, 06:18 PM   #22
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QuoteOriginally posted by stewart_photo Quote
I'm a bit suspicious of your results. Based on the shadows in your images, the primary light source in the room appears to be the window directly behind the remote. Therefore, most of the light in the room really isn't coming from a direction which would be impacted by a lens hood which obviously blocks light only from the sides. While I cannot explain the differences in your images, I also cannot explain how a lens hood would be all that effective in this particular lighting environment. That conflict suggests this needs further research in a controlled environment, certainly before the word "conclusive" is used.

stewart
Sorry Stewart i probably should have taken a wide angle shot of the room... there are 2 windows separated by a little bit of wall, one was positioned to the rear to cause backlighting and the other out of the frame and closer to the foreground for a lot of side light about 45 degrees off the line of the lens
01-19-2009, 06:33 PM   #23
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Thanks Mike. I notice a similar difference in performance for my Jupiter-9 85/2. That lens always has its hood in place!

Steve

01-19-2009, 06:36 PM   #24
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QuoteOriginally posted by MightyMike Quote
Sorry Stewart i probably should have taken a wide angle shot of the room... there are 2 windows separated by a little bit of wall, one was positioned to the rear to cause backlighting and the other out of the frame and closer to the foreground for a lot of side light about 45 degrees off the line of the lens
i can imagine it to be fair to be more privy when taking shots of your room

imma gunna steal ur wii
01-19-2009, 08:15 PM   #25
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Really well done and informative. Thanks!
01-19-2009, 10:37 PM   #26
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good info that I had not been aware of. well shot and written! Thanks Mike!
01-21-2009, 04:06 PM   #27
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Was there a filter on the lens?
01-22-2009, 01:37 AM   #28
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Mighty Mike--thank you so much for all of your diligent efforts in this thread. I will make more of an effort to put the hoods on my lenses!

Best Regards
01-22-2009, 10:10 AM   #29
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QuoteOriginally posted by Gooshin Quote
i use a lenshood designed for a film takumar 135mm on my FA43

until you get vignetting, there is no such thing as too much hood!

you also get slightly more accurate exposure.
QuoteOriginally posted by jezza323 Quote
well you have inspired me to go and buy a hoya 3 position rubber hood for my 50mm, very good comparison

thanks!

B&W 930 folding rubber tele lens hoods work well also. They're a bit more convenient than the 3-way hoods and use the same filter thread on both sides so you can leave the hood on your lens without using an additional (larger) lens cap.
01-22-2009, 06:28 PM   #30
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Excellent test! I will have to start looking for a hood for my FA50, don't want to miss out on that little extra, sweet sharpness
Do you have a picture of the lens with the new hood on?
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