OK, so what is the "standard" thread size of super large filters? A bit of a rant and a question...

[Michael Mutmansky]

I seem to be finding all kinds of conflicting information out there, so I'm looking for some information on 86mm and 95mm filter thread sizes from the good folks on Photrio.

I understand the "fine", "standard", and "coarse" thread sizes for rings and filters 82mm and below. Basically all normal 35mm lenses made in the past 75 years or so use the standard (0.75mm pitch) threads, but you will find that there are some lenses (like large format and an occasional other lens) might use a "fine" thread, or a "coarse" thread, which are 0.5mm (I think) and 1mm respectively. I've seen the fine thread on some optical barrels for assembly of optic element stacks, for example. Also seen coarse threads on some Large Format lenses. But basically, if you bought a "system" camera, 35mm or medium format, you were in the realm of the standard thread, except when they used Bay filters or drop in (thanks Hasselblad!).

However, starting at 86mm and going larger, there seems to be conflicting information. I'm seeing some people say that 95mm filters were ALWAYS coarse thread. If you go to B&H, you basically can't find specific information on the thread pitch on most of the filters of that size, except the Tiffen ones, where it appears they offer both a 95C and standard 95 in their offerings... OK, but which one is actually the normal, most-used thread pitch? Similarly, I see both 86C and standard 86 in some Tiffen filters.

Circling back to the MF forum, I am trying to get some filters lined up for the 350mm and 40mm Hasselblad lenses, and I believe they both use essentially the same 93 Bay filter adapter, which has an 86mm thread on the lens side. This I believe is an 86C thread from what I've read, so 86x1mm thread. I have read that one user reported that the Heliopan 111 step-up ring from 86mm to 95mm will work with the lens, but there's no information of the pitch on the Heliopan site. There does appear to be consensus on the 86x1mm thread pitch on the lens, however, so that should mean the heliopan 111 is 86x1mm.

So then, for the other end (the 95mm side), there again is no information what filter thread pitch is the "normal" at this size. So I feel like I need to buy blind or, before I do that, ask here if anyone is using a step-up ring on one or both of these lenses so I can get confirmation of the proper fit before I start purchasing filters, etc.

Because none of the manufacturers actually list the thread pitch for their products (except Tiffen, seemingly) actually knowing the true thread pitch isn't terribly useful... What I need is a confirmation that a specific step-up ring product (like Breakthrough, Polar Pro, Heliopan,, etc., I'd like to use a brass ring) will fit the lenses, and then that a specific filter (B+W, Breakthrough, Polar Pro) will fit that step-up ring.

Can anyone help confirm what I'm looking for? Anyone have this information specifically for the lenses I'm talking about based on experience?

More generally, at the 86mm and 95mm ring sizes, can anyone state that the industry uses Coarse threads as the default in their nomenclature so that when they don't state the pitch, the safe assumption is that they are talking in coarse thread pitch for the 86mm and 95mm sizes?


---Michael

 

[Dave Krueger]

I have a Hasselblad 40mm CF and use an AMOPOFO 86-95mm adapter ring from Amazon with 95mm B+W and Nikon filters. It's Aluminum, but I haven't had any problems with it.

 

[AnselMortensen]

Try checking with Tim Rice at www.filterfind.net
He's quite knowledgeable about such things and may be able to answer your questions.

 

[reddesert]

I don't know about any specific current filters or step rings. I feel like this is a case where hours of internet research could save several minutes of asking a knowledgeable person, like the filterfind.net person or customer service at B&H. However: the only really large filter-thread lenses I have are some Bronica wide angles that use 95mm thread, and they are definitely M95 x 1mm pitch (I looked). Bronica just writes "95mm" in their manuals. So back in the 80s-90s, they appear to have thought M95x1mm was standard.

 

[MARTIE]

My 100x100mm system is Heliopan
Their older document gives far more detail regarding internal/external filter and adapter thread sizes and pitch. Although in German, it's still fairly self-explanatory. Still available via wayback machine.

 

[Ian C]

Lens filters have long used the following code for metric thread:

F = 0.50 mm pitch

M = 0.75 mm pitch

C = 1.00 mm pitch

I believe that the Tiffen Company still lists the thread pitch as F, M, or C in its literature (at least, it did so a few years ago). It uses this system in the product code as shown below. About 2018, I needed a step-up ring for my 5.6/210 Super Symmar HM. It has 100 mm x 1.0 mm thread, but this size was only used on a few Schneder and Olympus lenses from the 1970s and 1980s. So, filters were essentially impossible to find at that size.

When I ordered my step-up ring from B&H in NYC, it had two 100 mm diameter Schneider step-up rings (SUR) that allowed the use of 105 mm x 1.0 mm pitch filters.

There were two versions: 100 mm x 1.0 mm pitch and 100 mm x 0.75 mm pitch. So, the buyer had to order carefully. I suppose that in the past, Schneider might have made some lenses with 100 mm diameter x 0.75 mm pitch.

Here are examples of 86 mm Tiffen filters.

The first one is listed as “Coarse” (1.0 mm pitch). I put the “C” in bold type within the codes where they indicate COARSE thread.

BH #TICC50Y86C, MFR #86CCC50Y

https://www.bhphotovideo.com/c/product/97687-REG/Tiffen_86ccc50y_86mm_Coarse_Thread_CC50Y.html

The otherwise identical filter with standard thread (M = 0.75 mm pitch) is the following. Note the difference in B&H and Tiffen codes:

BH #TICC50Y86, MFR #86CC50Y

https://www.bhphotovideo.com/c/product/97686-REG/Tiffen_86cc50y_86mm_CC50Y_Yellow_Filter.html

Most filters up to 40.5 mm diameter use F = 0.50 mm pitch thread

For 43 mm to 82 mm diameter, the thread is usually M = 0.75 mm pitch.

Filters from 86 mm to 122 mm diameter most often use C = 1.00 mm pitch

There are EXCEPTIONS, such as the 86 mm x 0.75 mm pitch and 1.00 mm pitch threading listed above.

Here’s a useful list of some diameters and corresponding pitches provided by the Marumi Company:

https://www.marumi-global.com/blogs...EZYuITfWfeOWcNjdIIGrHU9ZRTkP42XBYv7zgSDBAa7Op

Some large lenses use even coarser pitch. For example, the manual focus 600 mm f/4 AI ED-IF and first version of AIS telephoto lenses used 160 mm x 1.50 mm pitch front filter thread. So far as I know, the only filter made for these was the L37C UV filter. Filtering for effect was done with proprietary drop-in filters forward of the aperture.

https://www.mir.com.my/rb/photograp...ources/late70nikkor/telephoto/600mm.htm#optic

The last version of this manual focus lens was the 600 mm f/4 AIS-S ED-IF. It eliminated the front filter thread and instead used a built-in front filter.

https://www.mir.com.my/rb/photography/companies/nikon/nikkoresources/telephotos/600mm.htm

 

[Petrochemist]

Your assumption on smaller threads isn't quite right. Most are 0.75 pitch but some of the smallest are 0.5 pitch, and at least two sizes (43mm & 37mm) can apparently be found in both. Enlarger lenses often buck the standard pitches for 0.5 pitch for some that are larger (such as 49mm)

86mm & 95mm are both standardized at 1mm pitch, as are 105mm & 116mm (the largest size I have).
112mm seems to be 1.5 pitch

FWIW The standard metric pitches for bolts etc are all MUCH coarser than these. Filter pitches are significantly finer than even the extra fine pitches for bolt threads, M52 at 3 steps finer than regular is 2mm pitch, the normal pitch is 5mm pitch. Fortunately I never need bolts that big!
The standard for M12 bolts is 1,75mm pitch, none of my filters are quite that small, but all have finer pitches.

 

[Michael Mutmansky]

Your assumption on smaller threads isn't quite right. Most are 0.75 pitch but some of the smallest are 0.5 pitch, and at least two sizes (43mm & 37mm) can apparently be found in both. Enlarger lenses often buck the standard pitches for 0.5 pitch for some that are larger (such as 49mm)

86mm & 95mm are both standardized at 1mm pitch, as are 105mm & 116mm (the largest size I have).
112mm seems to be 1.5 pitch

FWIW The standard metric pitches for bolts etc are all MUCH coarser than these. Filter pitches are significantly finer than even the extra fine pitches for bolt threads, M52 at 3 steps finer than regular is 2mm pitch, the normal pitch is 5mm pitch. Fortunately I never need bolts that big!
The standard for M12 bolts is 1,75mm pitch, none of my filters are quite that small, but all have finer pitches.

The reason we are discussing this is because there seemingly IS NOT a standardized filter thread (at 1mm) for 86, 95, and possibly other sizes, but I have never looked into larger sizes.

The reason I say that is that Tiffen calls out their coarse thread filters with a "c" in the label, but they also sell the 0.75mm threaded 86 any 95 WITHOUT any thread pitch designation. If a coarse thread were the normal, standardized thread for those sizes, in Tiffen's mind, they would have labelled the other size with a "m" instead, but they didn't.

Then, you have this:

https://polarpro.zendesk.com/hc/en-us/articles/9045548366747-95mm-Thread-Pitch-Fitment

Basically, PolarPro believe that the 0.75mm thread pitch is the standard and they make a coarse version of some products.

Up above, Marte provides a link for the Heliopan filter system and it's absolutely clear that they standardized on 1mm thread pitch for 86 and 95. The #111 filter adapter step-up ring is clearly designated as an 86x1 to 95x1 and I have read specifically of one person using that with the 40mm lens. That would then mate with the 95mm Heliopan filters and I believe also the B+W filters as well, so those two manufacturers must be standardized on coarse (1mm) threads for those two sizes. However, it appears that the camera industry may have shifted on this a bit recently.

It's possible that digital camera manufacturers have moved more to the medium thread instead of coarse, and that might be why the current state of filters is the way it is, but then I guess the question is whether people buying B+W or other filters are facing a 50/50 chance that their filters they are buying are going to fit since the filter manufacturers haven't seemingly made any changes and they don't designate their thread pitch anywhere (for example; the same could be said for most filter manufacturers other than Tiffen).

Regardless, I think I have my answer based on information collected, so I will start accumulating what I need to do this. Thanks for all the feedback and information for everyone.

When I get it assembled, I will report back definitively on the thread pitch for the various parts in confirmation of a working system for others.

 

[Focomatter]

Back in the day I owned several Hasselblad lenses that used the 86mm accessory size. In the process of finding filters etc. for these lenses I ended up with some with a 0.75mm pitch so they do exist. One needs to be aware of this and ask for the pitch if it is not indicated.

 

[Petrochemist]

Back in the day I owned several Hasselblad lenses that used the 86mm accessory size. In the process of finding filters etc. for these lenses I ended up with some with a 0.75mm pitch so they do exist. One needs to be aware of this and ask for the pitch if it is not indicated.

I've found pitch often needs to be confirmed for M42 too. The M42 mount is 1mm pitch but T2 is 42mm at 0.75mm which many e-bay sellers list as simply M42

 

[Michael Mutmansky]

To report back for the next person trying to use filters on the 40mm and 350mm Hasselblad lenses...

The lenses have a thread pitch of 1mm. The Heliopan #111 86-95 adapter is the correct one. Breakthrough makes an 86-95 adapter ring that is 1mm thread pitch as well if you like their products. There are others out there for sure, including aluminum ones, but I wanted brass rings.

The filters I am using are B+W. Breakthrough does make polarizer and ND filters in this size and pitch, but I didn't get them in part because they initially gave me incorrect information that their filters were 0.75mm pitch so I ordered the B+W filters. I prefer the Breakthrough for the polarizer and ND in smaller sizes because they are more neutral and have better specs for what I wanted, but they blew it and it's too late for them. For the B&W color contrast filters, I am using B+W. Heliopan also makes filters that fit, but I'm mostly a B+W house so that's my preference.

Both B+W and Heliopan also make screw on lens hoods in the 1mm pitch at 95mm, so for the telephoto lens, you can buy one of those for a hood. I don't think anyone makes a wide angle hood that would work on the 40mm lens, but if I find a cheap used Heliopan short hood (they make a long and short), I may get it to modify at the corners. It might be a worthwhile project to test blockage a little and see what more shielding I could get at the 95mm diameter.

I decided to keep the adapter rings mounted permanently on the lenses and get caps that fit the 95mm size. In the case of the 350mm lens, that means the hood can be screwed in all the time and I just unscrew it to add filtration and then add the hood back on if there is sun flare conditions. I'm using the short hood, even on the 350mm, because, while I'm sure the long hood would be fine, it's a lot larger and I didn't want to deal with the size in my bag. I can always flag the front for the rare occasion where that is needed.

 

[Kodachromeguy]

For your 40mm lens, did you consider using the 93mm drop-in filters using the stock filter holder/hood assembly?

 

[Michael Mutmansky]

For your 40mm lens, did you consider using the 93mm drop-in filters using the stock filter holder/hood assembly?

No, because I didn't think I'd be able to find the filters I want in that size. I'm using the gear for B&W shooting, so I wanted color contrast filters, a polarizer, and a strong ND filter.

Over time, I'd certainly find the POL and some of the color contrast filters, but unlikely I'd find the ND. And even for the ones I did find, I'd prefer them to match the other ones I own so I can use the same filter factors for all of them on all the lenses while out in the field shooting.

So all said, I just thought it'd be easier to just bump up to the 85mm filters and be done with it.

 

[David Lindquist]

Coming to this thread a bit late. Back in 2016 I bought two 95 mm Formatt-Hitech filters for use with the Linhof 001933 filter holder (takes 95 mm filters with a pitch of 1.0 mm). They did not fit, pitch looks like 0.75 mm using my leaf-type metric thread pitch gage. Never did find anywhere where Formatt-Hitech described the thread pitch they used.

I also have 95 mm filters by B+W, Helioplan, Tiffen and Hoya. All have a pitch of 1.0 mm and fit the Linhof holder. Per my notes, only Tiffen tells you the thread pitch.

David