Smashing fun with a smashed filter

StewartR

StewartR

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Stewart
Edit My Images
Yes
OK, so we all know that putting a protective filter on the front of your lens degrades the image ... but by how much?

One of our customers had a mishap with this filter recently. We thought it might be fun to see what effect it had on images.
6209-1406723210-4f4b81f4d13af9641fe923e910cb83b5.jpg


You might be surprised by the results! I've written it up in this blog post:
http://lensesforhire.blogspot.com/2014/07/smashing-fun-with-filters.html
 
That's pretty revealing TBH
And to quote you ;)
And dust on the front of the lens ... don't worry about it!
 
I certainly wouldn't have expected such little effect on the images. Interesting read.
 
arad85 said:
I assume you've seen this blog post: http://www.lensrentals.com/blog/2008/10/front-element-scratches
Click to expand...
Yes, of course. It was good to have the opportunity to try it ourselves!
arad85 said:
Have to say I've found more issues with filters the longer the focal length. The one I tried last (which was an expensive filter) rendered bokeh terribly (it was on a 70-200 f4 which was a beautiful lens).
Click to expand...
That's interesting. On our Facebook page somebody has said "doubt with the decreased magnification you'd be able to get away with a broken filter so much with a wider lens , say 35mm". Methinks you can't both be right. Or maybe you can. Maybe by pure luck we picked the ONLY focal length where it doesn't matter very much... though Occam's Razor suggests not.
 
StewartR said:
Yes, of course. It was good to have the opportunity to try it ourselves!
That's interesting. On our Facebook page somebody has said "doubt with the decreased magnification you'd be able to get away with a broken filter so much with a wider lens , say 35mm". Methinks you can't both be right. Or maybe you can. Maybe by pure luck we picked the ONLY focal length where it doesn't matter very much... though Occam's Razor suggests not.
Click to expand...
200mm F4 Canon 450D. This was completely consistent - took me an age to figure out why I was unhappy with the output.

Without UV filter:
6211-1406741120-b1b9140620cfa99dfee0338e8ec99b6e.jpg


With UV filter:
6212-1406741121-5f505a43dc99da2c90892c1785193f7a.jpg
 
arad85 said:
200mm F4 Canon 450D. This was completely consistent - took me an age to figure out why I was unhappy with the output.

Without UV filter:
6211-1406741120-b1b9140620cfa99dfee0338e8ec99b6e.jpg


With UV filter:
6212-1406741121-5f505a43dc99da2c90892c1785193f7a.jpg
Click to expand...

Thats not a accurate test to show as the picture you claim without the filter is smaller than the one with a UV filter so even if they were the same the small size image will be better...
 
A broken front lens element or a smashed filter will affect contrast and flare but given the image is focused on the film plane or sensor it has very little effect on the image.
 
Joeturner11 said:
Thats not a accurate test to show as the picture you claim without the filter is smaller than the one with a UV filter so even if they were the same the small size image will be better...
Click to expand...
Err.. No.

They are the same size pixels (they are 100% crops). The photos were taken from the same position, with the same zoom - they are just not the same crops. The one with the filter has a wider field of view. Put them in Photoshop (or your favourite editor) and overlay them if you like.

If you don't want to believe me, don't. But this was a B&W filter that was never put back on the lens after those two photos were taken. In fact it was chucked in the bin - I wasn't going to palm it off on anyone....

In fact, I've done it for you... Here is the sharp one overlaid on the unsharp one.... Bottom, and both sides are most obvious...

6227-1406846128-70d70c2eb5399760e7749d8e9f818d88.jpg
 
arad85 said:
Err.. No.

They are the same size pixels (they are 100% crops). The photos were taken from the same position, with the same zoom - they are just not the same crops. The one with the filter has a wider field of view. Put them in Photoshop (or your favourite editor) and overlay them if you like.

If you don't want to believe me, don't. But this was a B&W filter that was never put back on the lens after those two photos were taken. In fact it was chucked in the bin - I wasn't going to palm it off on anyone....

In fact, I've done it for you... Here is the sharp one overlaid on the unsharp one.... Bottom, and both sides are most obvious...

6227-1406846128-70d70c2eb5399760e7749d8e9f818d88.jpg
Click to expand...

Errr...Thats better :) & Try not to get so hot headed and defence over a post next time (y)
 
arad85 said:
200mm F4 Canon 450D. This was completely consistent - took me an age to figure out why I was unhappy with the output.

Without UV filter:
6211-1406741120-b1b9140620cfa99dfee0338e8ec99b6e.jpg


With UV filter:
6212-1406741121-5f505a43dc99da2c90892c1785193f7a.jpg
Click to expand...

I am pretty certain this is a fake filter. You may have paid for a genuine one but I'd be very suspicious about it, particularly if the thread isn't brass or the font is slightly odd. I hope you took it back for a refund.
 
daugirdas said:
I am pretty certain this is a fake filter. You may have paid for a genuine one but I'd be very suspicious about it, particularly if the thread isn't brass or the font is slightly odd. I hope you took it back for a refund.
Click to expand...
As far as I could tell it was genuine (and yes, I did look extensively).
 
Joeturner11 said:
Errr...Thats better :) & Try not to get so hot headed and defence over a post next time (y)
Click to expand...
Try to be a little less accusative and condescending in your next post where you are telling someone they are wrong ;)
 
arad85 said:
As far as I could tell it was genuine (and yes, I did look extensively).
Click to expand...

They are getting better and better looking. Try simple genuine Hoya pro1D UV - you won't see that effect (I have that combo).
 
Very interesting blog - many thanks for sharing. Lets hope your customers don't take to scratching the front element to see what the effects are !
 
daugirdas said:
They are getting better and better looking. Try simple genuine Hoya pro1D UV - you won't see that effect (I have that combo).
Click to expand...
Don't have the camera/lens any more (I've moved to cameras that focus properly ;))...


...or any interest in using a filter again :)
 
Put the OPs filter on a Tokina 11-16mm, it will be very very noticeable.
 
daugirdas said:
They are getting better and better looking. Try simple genuine Hoya pro1D UV - you won't see that effect (I have that combo).
Click to expand...

Er -

Crops from a 100-400:

Unfiltered - Hoya Pro Elite Super-Dooper HD (whichever is the expensive one) - Noname

Filter%20Comparison%20100-400.jpg
 
arad85 said:
Err.. No.

They are the same size pixels (they are 100% crops). The photos were taken from the same position, with the same zoom - they are just not the same crops. The one with the filter has a wider field of view. Put them in Photoshop (or your favourite editor) and overlay them if you like.

If you don't want to believe me, don't. But this was a B&W filter that was never put back on the lens after those two photos were taken. In fact it was chucked in the bin - I wasn't going to palm it off on anyone....

In fact, I've done it for you... Here is the sharp one overlaid on the unsharp one.... Bottom, and both sides are most obvious...

6227-1406846128-70d70c2eb5399760e7749d8e9f818d88.jpg
Click to expand...

You should've kept that filter, would've been great for any portraits where you wanted to soften the detail. Could've saved you some time in photoshop. ;)
 
hollis_f said:
Check your facts before berating a poster, especially one with a reputation like Andy's.
Click to expand...

I'm with Joe here. I looked at the two photos, saw that they were different FOVs and different sizes and struggled to see what they were actually showing me. The overlay was infinitely more useful.
 
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