Vigneting in A200

[muko]

Hello guys....

Need all of your help and experience...

After buying c.polarizer HOYA for testing (i think c. pol somehow more appealing than UV filter)... and find out that it has vigneting then i am very doubtful to buy new filter or other lens add on.

so...
Last time during the gathering i try magicdragon's UV filter i think it was HOYA. And it has also this vigneting...
HOYA should be good enough right?
I see some of your lenses also use HOYA's.

so now.. i'm very confused...
Any better idea to protect lenses? better brand?

oya... btw what actually cause vignetting anyway?

Thanks guys....

[Joko1974]

Hi, could you please show any sample of the troubled picture? I've ever found the problem with my Canon PS-A70, not vigneting but reflection from the original lens ring by the inner surface of the filter.

[Drudkh]

Hi, the standard NOYA CP filter you bought is pretty thick. For most digicams that has as wide as 28mm, it will cause vidnetting. The only way to solve it is to get the Super-HMC CP filter which is much thinner, at least by 30% compared to the standard CP filter.

[Drudkh]

Originally Posted by Joko1974 Hi, could you please show any sample of the troubled picture? I've ever found the problem with my Canon PS-A70, not vigneting but reflection from the original lens ring by the inner surface of the filter.

to mount filters on your A70, requires an adpater. For A200, it does not.

[muko]

Originally Posted by Drudkh Hi, the standard NOYA CP filter you bought is pretty thick. For most digicams that has as wide as 28mm, it will cause vidnetting. The only way to solve it is to get the Super-HMC CP filter which is much thinner, at least by 30% compared to the standard CP filter.

hmmm...
So... for UV filter also the same then... just becoz it is too thick...
hmmm...

uv filter... uv filter...



by the way... with adapter dont have vignetting effect?

[Drudkh]

Originally Posted by muko hmmm... So... for UV filter also the same then... just becoz it is too thick... hmmm... uv filter... uv filter... by the way... with adapter dont have vignetting effect?

For A70, there's no screw thread at the front lens element, therefore it requires an adaptor to screw the fiters on. The filter size for A70 is way bigger than the diameter of the lens, that's why there won't be any vignetting.

For KM A1/A2/A200, there's threading at the front lens element, so at 28mm the standard filter is thick enough to cause vidnetting. So solve this problem is to buy Super HMC filters. You can refer to Hoya's website for more info. http://www.thkphoto.com/products/hoya/index.html

[Joko1974]

Originally Posted by Drudkh to mount filters on your A70, requires an adpater. For A200, it does not.

Yes, you are right. In my case the problem was with the adapter. Firstly, I thought the A200 has the same condition with mine. I thought it was Canon A200 but as I looked at muko public profile I knew that I was wrong. So, the problem is different with mine. I am sorry for my misunderstanding.

[Drudkh]

Originally Posted by Joko1974 Yes, you are right. In my case the problem was with the adapter. Firstly, I thought the A200 has the same condition with mine. I thought it was Canon A200 but as I looked at muko public profile I knew that I was wrong. So, the problem is different with mine. I am sorry for my misunderstanding.

No problem.

[TME]

Originally Posted by muko hmmm... So... for UV filter also the same then... just becoz it is too thick... hmmm... uv filter... uv filter... by the way... with adapter dont have vignetting effect?

U didn't try out the filter when u buy it after seeing that Magicdragon's filter also gave vignetting effects that night? The Super HMC should solve the problem... those who use the A200 should know if it works if they do use a UV or CP filter. On the other hand u could just take the camera down and test.

[Flare]

ER, did i read you right? Polariser to protect lens???

Oh no... another one kena... Polariser are generally not used for protecting lens ley, It's to polarize the light entering the lens, which could give some pleasing effects in certain conditions, like reducing reflection, make greenery more green, creating rainbow hue on clear plastics (not nice sometimes ) etc etc...

And due to this polarisation, which only allows light propegating in certain orientation of proppegation (sheesh wat's it called forgot my physics) to enter the lens, polariser will reduce the amount of light entering the camera, forcing you to need a longer exposure/wider aperture/higher ISO than it's needed to expose a scene compared to without the polariser...

Commonly UV filters are used to protect lens cos it's cheaper, and is suppose to block out UV light which could deteriorate the image... And they are clear and inexpensive.

[sulhan]

Originally Posted by muko Hello guys.... Need all of your help and experience... After buying c.polarizer HOYA for testing (i think c. pol somehow more appealing than UV filter)... and find out that it has vigneting then i am very doubtful to buy new filter or other lens add on. so... Last time during the gathering i try magicdragon's UV filter i think it was HOYA. And it has also this vigneting... HOYA should be good enough right? I see some of your lenses also use HOYA's. so now.. i'm very confused... Any better idea to protect lenses? better brand? oya... btw what actually cause vignetting anyway? Thanks guys....

Hi Muko.....

The vignetting effect that you get here is due to the thickness of the filter....i have this animation done up for you to show you the cause......

The filter actually cause a "shadow" on your imager as a resultant...


*the lens in the diagram is just bogus sketch....to show you the cause of the vignetting....the round area in green is the image circle and the rectangle in it is the CCD (front view)....

The thickness of the filter (red) is the cause of the problem. A thinner filter may help to reduce the problem.....

If the A200 have the "convertor" mode for the wide angle attachments....this mode may help to boost the corners alittle to a certain extent....if the the light fall off profile of the filter you are using is about the same as the one made by the convertors...try enable this mode to see if it helps a little....

rgds,
sulhan

[Agetan]

Originally Posted by muko Hello guys.... Need all of your help and experience... After buying c.polarizer HOYA for testing (i think c. pol somehow more appealing than UV filter)... and find out that it has vigneting then i am very doubtful to buy new filter or other lens add on. so... Last time during the gathering i try magicdragon's UV filter i think it was HOYA. And it has also this vigneting... HOYA should be good enough right? I see some of your lenses also use HOYA's. so now.. i'm very confused... Any better idea to protect lenses? better brand? oya... btw what actually cause vignetting anyway? Thanks guys....

What you might try is buy a step up ring, like 49mm to 62mm and use 62mm filters instead, that way you won't get vignetting.

I am happy with using that on my A2.

Hart

[Drudkh]

Originally Posted by Agetan What you might try is buy a step up ring, like 49mm to 62mm and use 62mm filters instead, that way you won't get vignetting. I am happy with using that on my A2. Hart

yes, that's another solution and a nice draw by Sulhan.

[muko]

Originally Posted by Agetan What you might try is buy a step up ring, like 49mm to 62mm and use 62mm filters instead, that way you won't get vignetting. I am happy with using that on my A2. Hart

ahhh... i see now...
Maybe i'll try this one...
So all of add on will be using 62mm right?
But then... what happen to my polarizer?
wasted... hmm...
O ya.. what about teleconverter do you use 62mm also?

anyway.. i buy polarizer when i buy the cam.. that's why i dunno the condition... and last time i thought that i can use polarizer all time.. so no need to buy UV.. but they are just making too dark. so cannot use all the time.

Thank you all..
and maybe i'll try sulhan's suggestion also tonight.

hmmmm.....

[Flare]

Originally Posted by muko ahhh... i see now... Maybe i'll try this one... So all of add on will be using 62mm right? But then... what happen to my polarizer? wasted... hmm... O ya.. what about teleconverter do you use 62mm also? anyway.. i buy polarizer when i buy the cam.. that's why i dunno the condition... and last time i thought that i can use polarizer all time.. so no need to buy UV.. but they are just making too dark. so cannot use all the time. Thank you all.. and maybe i'll try sulhan's suggestion also tonight. hmmmm.....

Anyway, you can still use lah, maybe juz that you may want to avoid shooting at your widest when using the polariser, i.e. zoom in a bit so that the vignetting don't appear.

By the way, stacking filters can also give vignetting, same reason as sulhan's animation.

[Drudkh]

for my A1, i have the super HMC polariser, so there's no vignetting. for normal shooting, i'll use either UV or Skylight filter. for shooting landscape or scenery that has sky, i'll mount only the polariser. its a bit troublesome but thats how it has to be. if you stack more than 1 filter, you loose at least 1 stop of light esp with polariser and of course the vignetting is even worse. you'll see black circle instead of just corners black. polariser is good for shooting through glass and windows too.

[Flare]

Oh yeah, of course remember that polarisers are designed to rotate for a reason. Rotating it determines what angle of light it polarises, thus giving different effect. Try it, you ought to be able to see it. Try pointing it outdoors (not noon tho, not when the sun is straight above you), rotate and try to note the difference in the sky, grass/greenery, reflection on glass/water.

Hahah... I do that with my polarized sunglasses too, if you see someone tilting his head this way and that with his shades on, it's probably just me taking photos with my eyes, head and a polariser.

[muko]

Originally Posted by Flare Oh yeah, of course remember that polarisers are designed to rotate for a reason. Rotating it determines what angle of light it polarises, thus giving different effect. Try it, you ought to be able to see it. Try pointing it outdoors (not noon tho, not when the sun is straight above you), rotate and try to note the difference in the sky, grass/greenery, reflection on glass/water. Hahah... I do that with my polarized sunglasses too, if you see someone tilting his head this way and that with his shades on, it's probably just me taking photos with my eyes, head and a polariser.

Yup.. i knowthat..
But rotating is 90 dgree right? becoz after 90 it should be repeating again.
is it correct?

[Agetan]

Originally Posted by Drudkh yes, that's another solution and a nice draw by Sulhan.

Eh, my name is hart.. not sulhan ler...

[muko]

btw... what thread size usually used in D 7D lenses?