These two answers are related and important. I think it is likely that if you are able to use a Lens Hood you’ll be unlikely to run out and buy a UV or Protection Filter for each of your lenses. IME people either do or do not and seldom change on this point. Also I’ll mention another point (below) as to why I think you will not change your mind on this matter.
The two filters nominated are specialty filters and in the course of a years’ shooting it is unlikely that the filters will remain on any lens for more than a few hours at each specialty use – this is important acknowledgement as we address other points, below.
As an initial strategy I suggest that you make an informed guess as to what lens(es) are more likely to utilize the ND and the PL / CPL Filters.
Some guidelines would be:
> PL / CPL will have limited uses for lenses with a FoV wider than 35mm on “Full Frame”. This is because the likelihood of Blue Banding is increased when a PC / CPL is used on wide FoV lenses.
> ND Filters (generally) get used on normal to wider lenses, rather than normal to telephoto lenses.
You might like to discuss what lenses you have and the filter size for each and we could get into more detail, however, as a general guide, I’d suggest that the “best option” is NOT necessarily to get a step up rings to fit a 67mm filter, or a 72mm filter if the lens(es) that are most likely to use those filters have a 58mm or 55mm thread.
The main reason is, you’ve got to fork out the money for a 67mm or 72mm CPL and ND (or two or three NDs) and the bigger the filter size the more expensive the exercise.
So I think the next step is to look at the lenses you have; identify what lenses that you think you’ll use the most with ND and CPL and base the main part of your choice on that.
The point is, you don’t know for certain how this journey will progress and whilst we might like to think that we will use these purchases often, often we don’t. It is often false economy to think that the better options is the one which provides the most flexibility.
As a practical example, I know that having purchased most of my gear as ‘business purchases’, the predominate factor always had to be ROI return on investment. As one example, there are many MANY “Wedding and Portrait Professionals” who make an absolute that a 70 to 200/2.8 is a “must have”. But when taken to task to identify how many sales there were by using that lens, where another lens definitely could NOT be used, that number was in the low single percentages of every Wedding Package; and usually it was only ever the “long shots from the back of the church” – which could easily be made with a 135/2 or 135/2.8 and a small crop in Post Production. The point is a 70 to 200/2.8 is about 5 times more expense than a 135/2.8.
You will know more about how often you use these Filters once you get them and begin using them.
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Goes to the question of filters and step up rings “binding”.
The major point here is that the intention is that the filters and rings will NOT be on the lens or other rings for a long period of time.
I think the binding issue is overplayed. I have quite a few sets of rings, it is because that they are so INFREQUENTLY used they never bind up.
I have never had a CPL or ND bind on a lens either – simply because it is only on for a couple of hours – and I regularly use the NDs at the beach, where there is humidity and salt water.
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Seems that “Landscapes” will be the main use for both ND and CPL, maybe the odd occasion “Sports” for CPL; maybe also Macro on the odd occasion for CPL.
As this is the case – we now look at what lenses your likely to use for “landscapes” and what Filter sizes those lenses have and refer to the points above.
The point is even if you buy new lenses with a 72mm thread, it’s likely you still use the lens with a 67mm thread.
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I think we put that in the “I don’t know” bucket and therefore we do not use it as a basis for any of the choices we make now.
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In summary, what to do:
I think that IF your 67mm Lens is likely to be the “often used” lens with the ND and CPL Filters – this is the size of Filters that you buy now.
If you buy 67mm Filters - then you might as well buy some Step Up Rings as well because they are a cheap as chips. I have never bought brass rings, for the reason I outlined.
I think that future lens purchases are not a relevant consideration at this time.
I think it is important to buy quality Filters, the main ingredients for CPL and ND is that they are SLIM Profile, have FRONT threads and have high quality optical glass.
Personally I don’t like Variable NDs, mainly because they do not reflect ROI for me: If I were a passionate Landscape Photographer (amateur or professional – it matters not) I would probably use a Variable ND, but for my spasmodic use, a few NDs is fine.
I do like my ND1000 (about 8 Stops) I use it the most often.
I think that a “Set” of quality ND Filters comprising: 3 Stops; 5 Stops and 8 or 10 Stops is more than adequate for a lifetime of general high quality Photography.
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ON the other hand -
IF you think that the most often used lens for the ND and CPL is one of the SMALLER Filter Sizes, then beware of buying a set of 67mm Filters and plan on using Step Up Rings - especially because you need to calculate the issue of OPTICAL VIGNETTING, especially if that lens is a towards the wider FoV.
WW