Daytime Long-Exposure Photography - ND Filter Question

[acroreef]

Dear Folks,

I'm interested in daytime long-exposure photography and need to purchase a 10 stop (at least) ND filter. I've read that filters that screw onto the lens cause vignetting problems. Is this always true? Also, I've seen the Lee "Big Stopper" and "Little Stopper" but the cost of the entire "rig" is around $500. Do any options exist that are not quite so expensive and also do not cause major vignetting?

Thanks in advance to all who respond.

Dave

[Manfred M]

Dave - I own the Lee gear (but not a Big Stopper) and 5-stop and 10-stop 77mm round ND filters.

Vignetting is more of an issue with wide angle lenses; i.e. the only one I see any issue with is my f/2.8 24-70mm lens on a full-frame body. Here, even with the Lee wide angle adaptor ring and the foundation kit, I get a tiny bit of vignetting at the very edges of the frame. Ditto for my 5-stop Tiffen and 10-stop B+W. If anything, the Lee is a bit worse than the B+W, but I would be splitting hairs here to say the difference is significant. Both issues can be dealt with in post quite easily.

Frankly, these are not "show stopper" issues...

[Polar01]

Dave: the Lee filter holder and mounting ring come in at around $150.00 US with the Big Stopper another $140.00 so I do not know how you come up with $500.00 I also have a 10 stop B+W round screw in filter, unless I go wide I find little vignetting problems. The thing nice with the Lee holder is that you can use Grads along with ND filters to help create the look you are after, however if it is only a 10 stop or less than the screw in would be better as there is less gear to carry. Now there is also the Singh-Ray vari filter I believe 2 to 8 stops which is what Colin swears by, which if I believe is correct it in the $450.00 range. Remember that you get what you pay for, so going cheap does not always work out.
Adding a link to a dealer in the US (Vermont) that I have found very useful as per information and service.

http://www.2filter.com/prices/catalog.html

Cheers: Allan

[acroreef]

I was just told by a local camera guy that one can mount two polarizing filters on the lens and they would act similar to a 10 stop ND filter. He was going to sell them (used) for $20. Seems that it is at least worth a try. (He stated this was an old "work-around" inexpensive solution to 10 stop ND filters). Any thoughts?

Dave

[Manfred M]

If you do this, two stacked filters are going to give you more vignetting and the other issues is that you will get banding when shooting wide angle shots. The other potential issue is a colour cast in your images. Trying to align two polarizers (with rotating front elements) is going to be a real pain.

I'd have to see the math, but find it unlikely that you are going to get a 10-stop ND that way. Frankly, if it were that easy, a lot more people would be shooting that way.

[Stagecoach]

Dave,

A short while ago I came across some work of a guy who was using 'welding glass lens' for this and delved deeper on the internet.

Some results achieved are surprising, there will of course be reasons why this will not provide equivalent IQ and cause colour casts that you may need to remove in PP which I would not dispute, but it is an option available out there.

Grahame

[acroreef]

Thanks again for all of the thoughtful and informed responses.

Dave