Step up rings and the effect to the picture

[Finnkare]

Do you know, does it have any effect on the picture if the filter is further away from the lens, after a step up ring for example? I mean, can you tell the difference between pictures taken through similar kinds of filters, but the one filter without a step up ring and another (bigger one) with a step up ring?

I have also considered, would it be wise to buy some cheap filters with a really bad condition glass, then take the glasses away and use the "bodies" as hoods. The most handiest solution here would be to put the filter furthermost, on top of all the bodies, but i don't know if it will affect picture quality, because the filter can be several millimeter further than normally...

It's boring when there's so many different filter threads... I don't understand how Zeiss for example can also make so big lenses, if you compare to Leica, at least the old ones...

[Finnkare]

So you think it doesn't matter how far the filter is from the lens?

[earleygallery]

The issue would be vingetting but you should be able to fit at least a couple of filters to any lens before you see a problem.

If you made a 'hood' from a few filter rings and then put the actual filter on the front the hood would be useless!

[masjah]

Originally Posted by earleygallery

The issue would be vingetting but you should be able to fit at least a couple of filters to any lens before you see a problem.

If you made a 'hood' from a few filter rings and then put the actual filter on the front the hood would be useless!

Agreed.

But the point at which vignetting becomes significant is probably different for every lens.

Just as an example, with the 35/1.4 Summilux R, Leica counsel against a standard polariser because its thickness would cause vignetting. They do though recommend their own E67 UV filter. However, a B+W slimline polariser is fine (in my experience) and is physically slimmer than Leica's own UV filter. So you can see where the limits for that particular lens lie. (By the way, 35 is about as wide as one should go with a polariser, because the variation of polarisation across the frame becomes too much with anything wider.) I guess it's got to be a question of suck it and see.

[Finnkare]

Originally Posted by earleygallery

The issue would be vingetting but you should be able to fit at least a couple of filters to any lens before you see a problem.

Well, after thinking about this I have come into the conclusion that there's no problem with step up rings as long as the ring is wide enough. An how wide? In order to ensure that the filter does not cause more vingetting than at the starting point, the width of the step up ring has to be at least 2x the height of the threaded part of the ring + the original filter thread. My logic says that if you go n mm left and right horizontally, and then n mm up, the light beams can travel just as they did without any added height on the lens barrel.

If I remember correctly, the threaded parts of Heliopan step up rings (and probably others too) are about 3mm high, which means that the step up ring has to be at least 6mm wider (ie 45 for 39, for example).

Of course it varies from lens to lens. With some lenses you might be able to use a step up even smaller than that, if the lens manufacturer has built a thread bit too large for convenience (uniformity) or just in case or for tradition or something. And if the lens is vingetting in the first place, with higher filters for example, the problem can be solved using a step up even wider.

The problem is worst with biggest aperture, and it's existence think it can be checked like this:
1) screw the "problem maker" (suspect) in place
2) put the aperture on the lens with which you want to see the results (most likely the biggest)
3) open the back of the camera, so you can see (something bright coloured) through the shutter
4) fire the shutter and leave it open as long as is needed
5) look through the lens, tilting it so that your sight is moving towards the corner of the frame

If you can see the corner of the sight you see through the lens disappear, you're safe. If you see the top of the "problem maker" (suspect) before the sight disappears, it's most likely gonna vinget. If the corner is vingetting, you can test if it's vingetting along the sides even. But that's probably really rare, most likely possible with step down filters only, or with a bunch of those empty filter bodies I mentioned.

Originally Posted by earleygallery

If you made a 'hood' from a few filter rings and then put the actual filter on the front the hood would be useless!

Hmm. I haven't actually ever been sure about this, since step up rings are not that common in photography literature. But maybe you're right.

But could it also imply that if you use a multicoated filter on a non-multicoated lens, it makes the lens (or the combination) multicoated?

[Finnkare]

Originally Posted by Finnkare

Well, after thinking about this I have come into the conclusion that there's no problem with step up rings as long as the ring is wide enough. An how wide? In order to ensure that the filter does not cause more vingetting than at the starting point, the width of the step up ring has to be at least 2x the height of the threaded part of the ring + the original filter thread. My logic says that if you go n mm left and right horizontally, and then n mm up, the light beams can travel just as they did without any added height on the lens barrel.

After some more thinking, maybe I'm a bit wrong here anyway. Maybe the principle above is true with a lens with diagonal AOV of 90 degrees, a 21mm. With longer lenses one could use also smaller rings.

Maybe.