Alternative to step up ring?

Patrick Cooper · January 1, 2016

I'm currently shooting a film that I'm going to submit to some film festivals. I'm going to have to reshoot one particular shot where there is a 'rack focus.' Depth of field wasn't shallow enough for my liking. Moving closer to the closest subject would of course help but I also need an ND filter as well. Unfortunately, I don't have an ND filter for this particular lens I'm using which has a 58mm filter thread. Ive got a few ND filters but they are either too small or too large.

Some time ago, I ordered a step up ring from interstate (via eBay) for this film I'm working on so that I could use my 67mm NDX4 filter on this lens. It was estimated to have arrived at around 16 – 18 December 2015. Still hasn't shown up. Unfortunately time is running out and as I'm currently on an island, I just can't go down to the local shop and get another step up ring because no such shop exists here.

Which brings me to my main question – has anyone been resourceful enough to use a filter on a smaller diameter lens without a step up ring? Of course some people use filters on lenses without any filter thread so there must be a way. With regards to using filters on lenses with no filter thread, I thought of some way of doing that in the past but I can't remember the exact plan I came up with. Think it may involved wrapping some soft material tightly around the front of the lens and maybe a rubber band as well. Guess I could try and wedge the filter into the material and hope it stays in place.

Edited January 1, 2016 by Patrick Cooper

David Mullen ASC · January 1, 2016

People have taped filters to the front of lenses before.

Patrick Cooper · January 1, 2016

People have taped filters to the front of lenses before.

Ah cool. I didn't think of that option before. As in taping it on to the lens' filter thread? I guess I'll Just have to try and be super careful not to scratch the filter with the smaller diameter filter thread.

David Mullen ASC · January 1, 2016

You don't want to put a filter that is so small as to be touching the glass of the lens, unless you have some sort of clear filter in front for protection. I've taped filters that were only slightly smaller, just inside the metal ring but outside the glass, but I've never tried to put a filter that was smaller than the glass area, for lots of reasons -- vignetting, light leak around the edges of the filter, scratching the glass, etc. As for a filter that was bigger than the front, you just have to be careful when taping it on. You could make a ring of tape around the metal edge of the lens that both keeps the metal from touching the filter but also acts as an adhesive.

Patrick Cooper · January 1, 2016

David, thankyou for the idea. When the light is right (preferably late afternoon sunlight) I'll get to work on that ring of tape around the edge of the lens.

Satsuki Murashige · January 1, 2016

When taping a larger filter to the front of a lens, first attach four small tabs of gaffer tape to the metal filter thread of the lens. By putting them at the top, bottom, left, and right you will create a soft buffer between glass filter and metal lens housing, preventing scratches.

Next, take a strip of 2" gaffer tape about the same diameter as the lens front and attach 1" to the front of the lens housing, making a ring of tape that overhangs the front lip of the lens. It should look like a short lens hood. Then take scissors and carefully cut the 'lens hood' into strips. When you fold the strips back over the lens, it should look like flower petals opening.

Finally, press the filter gently into the sticky tape 'petals' and fold the tape over the front of the filter. Finish off with another strip of 1" gaffer tape under the bottom of the filter and secure to the lens housing. This will work for large square filters as well as round filters.

Now, the bad news is that an NDx4 is only a 2 stop reduction of light, so that may not be enough to allow shallow focus in late afternoon light. If you have a polarizer, you might consider taping that on as well. A Pola should buy you 1.5-2 stops of extra light reduction.

Patrick Cooper · January 1, 2016

Satsuki, thanks for the tips.

Now, the bad news is that an NDx4 is only a 2 stop reduction of light, so that may not be enough to allow shallow focus in late afternoon light. If you have a polarizer, you might consider taping that on as well. A Pola should buy you 1.5-2 stops of extra light reduction.

Yea true. Though at least it's better than shooting at f16 like I was! I also have an NDX8 filter but that has a diameter of 52mm so not really a viable option as it would cause vignetting.

If you have a polarizer, you might consider taping that on as well. A Pola should buy you 1.5-2 stops of extra light reduction.

I used to have a polariser years ago but it was defective so I got rid of it. I think I will position the lens physically closer as well as use the ND filter - hopefully that should provide acceptable results.

Edited January 1, 2016 by Patrick Cooper

Sraiyanti Haricharan · January 2, 2016

Having similar problems recently, I've invested in a filter set.

http://www.ebay.in/itm/like/151731372088?aff_source=Sok-Goog

This is going to make things SO much easier in the future and also isn't expensive. :)

Hope the taping worked out.

Patrick Cooper · January 27, 2016

Having similar problems recently, I've invested in a filter set.

http://www.ebay.in/itm/like/151731372088?aff_source=Sok-Goog

This is going to make things SO much easier in the future and also isn't expensive. :)

Ah nice find. I should really get a graduated ND filter myself one day for landscape work.

Hope the taping worked out.

I was just about to use the tape method but then the adapter ring finally arrived. Certainly makes things nice and simple.