ND Filter

skimmel · 05-22-2005

I'm thinking of getting a neutral density filter for my M7 for shooting in bright sunlight when I have 400 film but want to open up the aperature.

First of all, does this sound like a good idea?

Second, which filter would you recommend? Leica, per B&H site, has 2 different ones (neither in stock). I'm not sure I understand the difference:

Leica Series 5.5 Neutral Density (ND) 1x Glass Filter

and

Leica Series 6 Neutral Density (ND) 1x Glass Filter

What's the difference between these? Are other brand (e.g., B+W) comparable to the Leica filter?

Thanks.

ray_g · 05-22-2005

The difference would be in the filter diameter, since both are 1x. 2x and (especially) 4x would be darker, and may help you achieve the effect you want.

Others will correct me if I'm wrong, but the series 5.5 should fit 39mm, such as the Summicron C 40/2. Series 6 is likely for older version Leica R lenses, such as the 35mm Elmarit R and 50/2 Summicron R first version.

ray_g · 05-22-2005

Oh, and yes, I have had good experience with B+W filters. Heliopan and Hoya MRC are good too.

jdos2 · 05-22-2005

I've an 8x for my Noctilux- it allows me to shoot wide open on Pan F, and nearly wide open (or I can accept the increased color saturation!) on 100 speed color.

Get it. Coated is best, do know that in some circumstances it will, like all other glass, contribute to flare. I've a single picture out of all the 20 rolls I took on vacation that has a beautifu rainbow across the center, from the filter.

richard_l · 05-22-2005

A 1x filter won't block enough light for your purpose. You need at least a 2x (1 stop), 4x (2 stops), or 8x (3 stops). If you stack them, the filter factors multiply and the stops add. For example, a 2x stacked with an 8x makes a 16x (4 stops).

I use a B+W 4x and an 8x, which gives me a choice of 2, 3, or 5 stops. Hoya also makes good filters. I have a couple of Leica contrast filters which I got used, and they don't work any better than the other brands. The price of new Leica filters is way too high, in my opinion.

Roger Hicks · 05-22-2005

Um... You can't have a 1x. That would be clear glass. Maybe 1 stop (=2x)? Or ND 1.0 (=10x). Take a look at the free module on density in the Photo School in www.rogerandfrances.com.

'Series' filters are not threaded: they are dropped into holders, which may be built into the lens hood, e.g. my old Summilux takes Series VI.

ANY decent quality filter will produce no detectable deterioration in the image on the film. B+W are fine; so are many others. Duff filters disappeared for the most part decades ago.

Cheers,

Roger

skimmel · 05-23-2005

Thanks everyone for the advice.

Yes, I was very confused about the "1X" designation. Didn't know if it was an incorrect description on the B&H site or some strange Leica-way of designating 1-stop.

It definitely makes sense to go with "stronger" ND filters and being able to stack them. Thanks.

Just want to say (if I haven't already): this is a great forum.

skimmel · 05-23-2005

A follow-up question: looks like coated B+W ND filters are hard to find. Would you go for a non-coated B+W vs. a coated Hoya? (I have only used B+W in the past few years so know nothing about current Hoya filters.)

richard_l · 05-23-2005

I've seen UV and skylight filters rated 1x. In the case of ND filters it may be something like 1.2x (1/3 stop) rounded down to 1x, or it could be a misprint.

I bought a couple of Hoya contrast filters recently. Optically they appear perfect. The rings may be aluminum, however. (Anyone know for sure?) B+W are brass (I think), which are not as likely to bind. Are you sure B+W NDs are uncoated? Maybe they're just not multicoated. I believe Heliopan (another good brand) also has brass rings.

skimmel · 05-23-2005

Thanks richard_I.

You're correct, B+W does have multicoated ones but they're "special order" at B&H (estimated 6-10 *weeks*) and not listed at all at Adorama.

I'm very curious about the rings on filters since it's likely I'll be changing them a lot.

skimmel · 05-23-2005

Just found this which seems like a pretty balanced view. B+W and Heliopan do use brass rings per this site:

http://photonotes.org/articles/filters/

What is the material of the filters threads on the Leica 50mm summilux?

Mazurka · 05-24-2005

Multicoating on ND filters is not a must because it does more to increase light transmission than reduce flare - and the whole point of an ND filter is to reduce brightness.

An 8X (3 stop) ND filter is a good choice for ISO 400 film. It is also indispensible if you do any daylight fill flash with the M's 1/50 sync speed. If you are concerned about flare, just use a lens hood.

I prefer not to stack filters, even NDs, in order to keep internal reflections of the whole optical system to a minimum.

skimmel · 05-24-2005

Thanks Mazurka. I went by my local camera shop today -- B+W doesn't even list multicoating on its 8X ND filter (but do on the 4X and 2X) -- wonder if that's because of the issue you mention of increase in light transmission.