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11-23-2010, 10:05 AM   #1
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Is a filter necessary for the DFA100mm WR?

Yup, the title says it all.

Given that the glass is quite recessed into the body, the filter will be quite far away from the glass. If i put a filter on, does it degrade IQ more than it would usually?

Is a filter even necessary and on a side note, is constant lens-pen cleaning of a lens harmful to a lens? It's something that kinda niggles. Everytime i have to clean the dirt and marks off my attached filters(on other lenses), i'm so glad they are on, expensive that they were.

Thanks for the enlightenment

11-23-2010, 10:15 AM   #2
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This is more of a personal preference. Some say that a UV filter will degrade IQ and others say it won't. I have done some side by side test with the 18-55 lens and could see what I thought was a light drop in IQ BUT it was so small that it could have easily been in my head. Then some say that the extra protection is worth the trade off in IQ.

As for the constant cleaning with a lens pen, I would say that in the long run it could and maybe will leave cleaning marks. I have seen some people lists lenses on the marketplace with "cleaning marks" in the description. My first line of defense when cleaning all my lenses is to first use a blower and if that doesn't work then I will use my pen.
11-23-2010, 10:15 AM   #3
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QuoteOriginally posted by ohyouloveme Quote
Is a filter even necessary and on a side note, is constant lens-pen cleaning of a lens harmful to a lens? It's something that kinda niggles. Everytime i have to clean the dirt and marks off my attached filters(on other lenses), i'm so glad they are on, expensive that they were.
UV filters are unnecessary and degrade IQ. Filters like circular polarizers are necessary for an intended effect, but likely should not stay on all the time.

Constant cleaning will degrade lens quality too. Look at the front of your lens. Is it dusty? Leave it be. Clean off oil and water, but never dust. You can't see dust on a lens in pictures.

This is how you should clean: blow the lens, then lightly brush a lens, and if there is oil/water, THEN use something like a lens pen VERY GENTLY. Otherwise you will grind dust and grit into the lens and scratch it... making it worse than when you started.

In my book, you should only have to clean a lens on an annual basis. The less the better. Keep your fingers out of there with a hood, keep water away (always do this anyways), and don't worry about dust. Dust should blow right off anyways, which is a completely safe method of cleaning.
11-23-2010, 10:16 AM   #4
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As for the IQ drop with a UV filter.... the problem is ghosting with lights. Bright lights in the frame will leave behind a green "ghost". Try it yourself and decide if it is acceptable.

In some images you won't see the UV filter, but I've ruined a fair number of pictures full of green ghosts. (GOBLINS!!)

11-23-2010, 10:21 AM   #5
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The general consensus is that permenantly leaving a UV or Skylight filter on the lens isn't necessary although in some harsh conditions it is needed. Another piece of glass can cause flare and possibly degrade the image some. A search will probably find a few dozen threads discussing the need for filters. I have filters in sizes to fit most of my lenses but I leave them off unless I feel I need to put one on to protect the lens, such as wind/sand and ocean spray, etc.
11-23-2010, 10:27 AM   #6
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thank you for sharing your experience, kxblaze. if the trade-off is a drop in IQ that runs circles in my head making me wonder whether there is a difference, i will most certainly put on a filter.

i have bought a $16 filters that totally ruined my kit lens's IQ, and hoya HDs that really set my mind at ease. i have not done testing with and without the hoya HDs but i must say thus far i feel safe that my lens is protected(from the need to clean, if anything), and IQ isn't degraded much.

i'd love to hear more experiences from you guys, with this lens in particular. the feeling that the glass being so far away from the filter intrigues me because my intuition tells me that there might be a factor of difference.
11-24-2010, 02:14 AM   #7
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with shorter macro lenses I think a protective filter is a good idea, due to the fact that working distances are much shorter, the closer you get to your subject the potential for damage or debris getting on the lens rises. It is true that you can put a piece of blu tak the size of a pinhead* on the front of your lens and even at f/16 it will be difficult to spot, but dust and crud getting on a lens surface can potentially cause scratches and cause flare. I think it sensible to put a High quality protective filter on macro lenses 100mm and shorter.

*the shorter the focal length the more obvious such a thing becomes.

Last edited by Digitalis; 11-24-2010 at 02:21 AM.
11-24-2010, 11:24 PM   #8
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I've tried 2 different UV filters on my D FA 100 WR.

No, not both at the same time.

I used one, then tried the other afterwards. One Hoya, and one off-brand (both brand new and spot free). Each one missed focus at least 1 out of 3 times. The camera would lock focus, yes, but it was easy to see that it wasn't properly focused on what I was shooting.

This was in daylight with the sun behind me and lens hood in place. I was trying to get still pictures of flowers, and also while taking a portrait of my girlfriend. When I removed the filter, I had no problems at all. Since that day, I use that lens naked. I think it may have to do with the distance between the filter and the lens. Obviously it wouldn't focus on the filter that close, but it did seem to throw it off a bit.

Anybody else have this issue with filters on this lens?

11-25-2010, 02:15 AM   #9
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QuoteOriginally posted by ohyouloveme Quote
thank you for sharing your experience, kxblaze. if the trade-off is a drop in IQ that runs circles in my head making me wonder whether there is a difference, i will most certainly put on a filter.

i have bought a $16 filters that totally ruined my kit lens's IQ, and hoya HDs that really set my mind at ease. i have not done testing with and without the hoya HDs but i must say thus far i feel safe that my lens is protected(from the need to clean, if anything), and IQ isn't degraded much.

i'd love to hear more experiences from you guys, with this lens in particular. the feeling that the glass being so far away from the filter intrigues me because my intuition tells me that there might be a factor of difference.
Sorry for the OT, but are there Hoya HDs in the 49mm thread for the limiteds?
11-25-2010, 07:02 AM   #10
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QuoteOriginally posted by r0ckstarr Quote
I've tried 2 different UV filters on my D FA 100 WR.

No, not both at the same time.

I used one, then tried the other afterwards. One Hoya, and one off-brand (both brand new and spot free). Each one missed focus at least 1 out of 3 times. The camera would lock focus, yes, but it was easy to see that it wasn't properly focused on what I was shooting.

This was in daylight with the sun behind me and lens hood in place. I was trying to get still pictures of flowers, and also while taking a portrait of my girlfriend. When I removed the filter, I had no problems at all. Since that day, I use that lens naked. I think it may have to do with the distance between the filter and the lens. Obviously it wouldn't focus on the filter that close, but it did seem to throw it off a bit.

Anybody else have this issue with filters on this lens?
thanks for sharing your experience. i am curious as well whether this lens will take in filters well.

QuoteOriginally posted by gtl Quote
Sorry for the OT, but are there Hoya HDs in the 49mm thread for the limiteds?
no, Hoya HDs do not come in 49mm threads.
11-25-2010, 03:20 PM   #11
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QuoteOriginally posted by ohyouloveme Quote
thanks for sharing your experience. i am curious as well whether this lens will take in filters well.
I have used UV filters for the last 4months on mine, I have used 2 different no-name brands on it. I prefer to use them for a host of reasons.

I notice no real image degradation at all, and am more than happy with the cheap filters and the decent images the lens has allowed me to produce. Every image in my flickr stream taken with the 100mmWR has used a cheap UV filter. (I think of them as see-thru lens caps)
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