Ok to use step-down rings with a CPOL filter?

[djwalker575]

Apologies in advance if this is a silly question, I'm rather new to filters.

I make my living as a videographer, shooting on a Canon 60D. I also do a fair amount of photo shooting for my clients. I need a ND filter to be able to shoot in fairly well lit environments with a very shallow depth of field (f1.4 is ideal).

I do, however, really like the look that a good circular polarizer gives to images, and in researching them I found that they also can act as a ND filter and can give up to two stops of brightness control. Only thing is, I shoot most of my stuff with either a Canon 50mm f1.4 (58mm filter size) or a Canon 70-200mm f2.8L lens (77mm filter size).

I've heard of step-down rings that allow filters to be used on different size lenses, is this an option here? Or would it just be weird/bad to be using a 77mm filter on a 58mm lens with step-down rings? It would be pretty nice not to have to buy multiples of the same filter just to accomodate the two lenses.

 

[KmH]

You bet!

Many people buy just one large size, high quality, multi-coated CPL or ND filter(s) and an assortment of step rings to use that large filet on smaller filter thread lenses.

To use a 77 mm on lens having 55 mm filter threads you would use a step-down ring.

Heliopan 145 Adapter Ring 77/58

 

[djwalker575]

You bet!

Many people buy just one large size, high quality, multi-coated CPL or ND filter(s) and an assortment of step rings to use that large filet on smaller filter thread lenses.

To use a 77 mm on lens having 55 mm filter threads you would use a step-down ring.

Heliopan 145 Adapter Ring 77/58

Awesome, thanks!

On a side note, that seems pretty expensive for an adaptor. Would one like that really be that much better than something like this?

Amazon.com: Top Brand Step Up Ring 58-77mm Lens Filter Size Adapter: Camera & Photo

Generally speaking, I try to avoid going for the cheaper route with things like this, but it doesn't seem like there would really be that much to an adaptor.

 

[Derrel]

RE: http://www.amazon.com/Brand-Step-58-77mm-Filter-Adapter/dp/B0002ER2OG

YES.

 

[Ernicus]

I could be wrong here, but I'll put it up since no one else has...when stepping down, don't you need to be worried about excess vignetting? Or is the verbiage of step down vs step us at play here? Obviously a larger filter on a smaller lens is fine, but when using a small filter on larger lens is typically a bad idea. As stated above by keith, most use buy larger filters and rings to accomodate the smaller lenses they have.

 

[Derrel]

I could be wrong here, but I'll put it up since no one else has...when stepping down, don't you need to be worried about excess vignetting? Or is the verbiage of step down vs step us at play here? Obviously a larger filter on a smaller lens is fine, but when using a small filter on larger lens is typically a bad idea. As stated above by keith, most use buy larger filters and rings to accomodate the smaller lenses they have.

Well...the angle of view of the lens in use is a big determining factor in vignetting or not vignetting; on a narrow-angle lens, like say a 50mm f/1.4 Canon lens that has a 58mm filter thread, the step-ring is still...58mm...so...there ought never be any vignetting. Also, the 60D is a crop-frame, and so there is a HUGE, huge peripheral image area that the SENSOR simply can NEVER "see"...the roughly 43mm diameter image circle that a 50mm lens for 35mm film/d-slr is not even remotely used by the smaller, 1.6x FOV sensor in a Canon 60D, or other similar cameras.

Now...if the lens is question were say...a 16mm circular fisheye...there might be some vignetting...

STACKING two, or three filters might also cause vignetting when used with a really wide-angle lens.

But generally, a step ring is going to have a filter size that matches (perfectly matches,in fact), the filter ring dia. of the taking lens....so vignetting is "usually" not too big of an issue, and with a 50/1.4 EF used on a crop-sensor, the chance of vignetting is virtually nil.

 

[KmH]

Get the best step ring you can afford. By the same token, get the best CPL and ND filters you can afford.
B+W Schneider Optics 77E SLIM KAESEMANN CIRCPOL MRC 77mm Polarizing Filter

 

[djwalker575]

Get the best step ring you can afford. By the same token, get the best CPL and ND filters you can afford.
B+W Schneider Optics 77E SLIM KAESEMANN CIRCPOL MRC 77mm Polarizing Filter

What exactly do you get with a pricier step ring?

I absolutely understand getting the best filters possible, makes no sense to put cheap glass in front of your expensive glass, but I'm curious as to what you actually get with a $50 step ring vs a $3 one. It's all a business expense and I try to never go the cheap route if it will affect the quality of my services, but for some things you get what you pay for and for some you don't as much.

Thanks for the responses!