Cheap filters and the difference in IQ


Aimevous

Senior Member
Mar 5, 2009
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#1
Hi,

Here's something up for casual discussion.

I found an old and cheap filter in my dry cab and decided to test it against
my A850 (24 megapixel full frame camera) with a CZ 16-35mm (arguably one of the best wide angle lenses)

Below are two set of images, 100% crop, one with and one without the cheap $10 filter. Pictures are straight out of camera and 100% center crop.

Shot at F2.8


Shot at F8



Can you tell which is which? :dunno:

(sorry for the difference in size for the 1st set, forgot to turn off auto resize when uploading, but I suppose it didn't resize it too much so i didn't bother to upload again..)
 

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daredevil123

Moderator
Staff member
Oct 25, 2005
21,657
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lil red dot
#2
Do you mind doing tests:

1. With the sun in the frame.

2. Night shoot with bright street lights.

;)
 

Jan 5, 2010
276
0
0
#3
Based only what you have posted here and may not be the best test scenarios.......

The 2nd pix for both are a tinge brighter, but looks slightly hazier. Comparing the bright ledges on the right and shadowed balcony windows on the right and centre, the pix 1 details are clearer in definition.

Not sure what filter you are referring to, I might have an idea but and not making a wild guess at that.......I'm only a noob!:embrass:
 

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Aimevous

Senior Member
Mar 5, 2009
787
0
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#4
@daredevil: ah i think i know what u are driving at.. Yah i think flare will be an issue. I havent had any really expensive filters before, and the most expensive one i ever had was this ed one by hoya for my previous zeiss - sony cz 1680mm and under strong direct spot light, i get tonnes of flares.. Was wondering if the zeiss and b+w ones could avoid those. I heard from some friends that they still do flare a bit..
But i'l try the tests too maybe this weekend when im free!

@marlin: yep i agree this is not the best test conditions.. Woke up and thought i should do a test..and thats it. Haha.. And btw this is a cheap filter by the brand of fotga which i got from ebay to protect this old 77mm lens of mine. Sold it so though i could try it on this new lens of mine.

(pardon my brevity, replying using mobile phone somewhat poses a challenge to me!)
 

Octarine

Moderator
Staff member
Jan 3, 2008
12,516
30
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Pasir Ris
#5
Please provide 100% crops from objects in the corner of the frame as well.
 

#6
i would say the 2nd image is with the filter. lower contrast and somewhat smudgier.

I used to have a hoya UV which made all the pictures soft and low contrast. i almost sold of the lens cos of it! then i realized it was the filter problem so now i either use only the filter ring(smash out the glass) which protects the front of the lens from getting dented, or for my best lenses i buy hoya's pro 1D filters.
 

Aimevous

Senior Member
Mar 5, 2009
787
0
16
#7
Hmm, actually... the 2nd image is the one without the filter.
Personally I can't see much difference between both sets. Not sure about the perceived blurness here though.. but this is interesting.

I'll try and find time to do a more definitive test.. its kinda heavy to bring an a850 + 1635 out..
I also noticed a slight difference in brightness levels, wondering it could be due to the 10 or so seconds in slowly unscrewing out filter early in the morning (changing lighting conditions)...

But so far it seems like under "usual" conditions, any difference is not noticeable, even if its a cursory pixel peep?

Agree?

Meanwhile, thanks for all your response guys!
 

small pig

New Member
May 17, 2011
919
0
0
Punggol
#8
Wow. Indeed no much diff. Unless we are talking abt flare , guess I can go abt buying some cheap filter esp like ND which don't really affect the iq
 

Aug 16, 2010
1,049
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0
24
Japan, Tokyo
#9
Wow. Indeed no much diff. Unless we are talking abt flare , guess I can go abt buying some cheap filter esp like ND which don't really affect the iq
I think you should reconsider that. Just my 0.02 cents. =)
 

Oct 20, 2010
1,087
0
0
Shanghai, China, China
#10
The difference is the color cast and the fact that the filter actually blocks a bit of light, making shots 1&3 a shade darker.

I didn't try with/without filter, but I did try a cheaper filter and the B+W and the later was more neutral. Since then I only use B+W.
 

donut88

Senior Member
Nov 14, 2008
2,182
5
0
#11
Aimevous said:
Hi,

Here's something up for casual discussion.

I found an old and cheap filter in my dry cab and decided to test it against
my A850 (24 megapixel full frame camera) with a CZ 16-35mm (arguably one of the best wide angle lenses)

Below are two set of images, 100% crop, one with and one without the cheap $10 filter. Pictures are straight out of camera and 100% center crop.

Shot at F2.8


Shot at F8


Can you tell which is which? :dunno:

(sorry for the difference in size for the 1st set, forgot to turn off auto resize when uploading, but I suppose it didn't resize it too much so i didn't bother to upload again..)
I don't use any filters now. My filters come come free with the lens, which I doubt its effectiveness. How good can a free filter be?

Instead, I make use of lens hood to protect my lens. And night shots, it's best not to use filter at all. So might as well, do away with filters.
 

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