Filters (Page 2): The real benefit to rectangular filters is using them for graduated ND or other effects. The rectangular holder lets you more precisely locate the transition within...

Orphoto Loc: Oregon

The real benefit to rectangular filters is using them for graduated ND or other effects. The rectangular holder lets you more precisely locate the transition within your frame.

However, for really long exposures you want a solid neutral density, not a graduated or split. Typically you are looking at 6 stops or 10 stops change. Screw in filters work especially well because you don't have any risk of light leaks and you are not mounting an awkward contraption on the end of your lens. Buy one filter in the largest size you need and get a sufficient number of step up rings to cover the rest.

Key considerations are optical quality of the filter glass and just how color neutral it is.

jcboy3

TriX wrote:

Good point, but almost all the listed polarizers are CPLs last time I checked KEH.

Old filters don't have the multi-coatings of new filters. Stick with CPLs.

TriX Loc: Raleigh, NC

jcboy3 wrote:

Old filters don't have the multi-coatings of new filters. Stick with CPLs.

That too. Modern coatings have made a positive difference in filters as well as newer lenses.

tcthome Loc: NJ

Ednsb wrote:

Over the years I’ve always used circular filters m... (show quote)

Any question, contact them. Only reason to go square =rectangular is a gnd filter. Reverse gnd for sunrise/sunset photos. I don't use any of these, but they get great reviews. I'm using Wine Country Camera 150mm kit purchase for the Nikon 14-24 lens. Huge & expensive!! Quality seems alright. Most square filter holders come with a circular polarizer option or included. The Polar pro set-up comes with a sun shade/hood & square/rectangular filter frames so you don't have to put you fingers on the glass. The frames slip into the holder mounted on your lens. Some links below. Good luck & have fun.

https://kasefiltersusa.com/

https://www.polarprofilters.com/collections/filters

https://breakthrough.photography/

https://nisiopticsusa.com/

happy sailor Loc: Ontario, Canada

I have the Lee holders and some of their cheaper filters. I read about Blue Frog filters out of Florida and decided to try them out. The customer service was excellent and the product seems to be high quality. I bought their kit that included the 10 stop and the six stop filters and a cpl. The kit came with the square filter holder and step down rings in 62, 67, 72 and 77 sizes. The holder itself is 82mm. I have been very happy with the images I have created using these filters and will probably buy more from Blue Frog. I have not experienced any colour cast.
https://bluefrogfilters.com/

burkphoto Loc: High Point, NC

Ednsb wrote:

Over the years I’ve always used circular filters m... (show quote)

A circular polarizer is not circular because it is round. It is 'circular' because of what it does to the light. Circular polarization is needed for digital photography because of the way that most common digital sensors work.

jcboy3

burkphoto wrote:

A circular polarizer is not circular because it is round. It is 'circular' because of what it does to the light. Circular polarization is needed for digital photography because of the way that most common digital sensors work.

Circular polarizers are needed for DSLRs because of the mirror. They are not needed for mirrorless cameras. However, because of the DSLR market, most polarizing filters developed in the past decade were circular, and were developed with improved coatings.

A circular polarizer is actually a combination of a linear polarizer and a quarter wave plate that produces cirularly polarized light (basically redistributing the polarized light that comes through the linear polarizer). Which is why a CPL has a different effect if you mount it backwards.

While you don't need a CPL for mirrorless cameras, modern CPLs have improved coatings to improve transmission, and are much more commonly available.

The only application I have had for linear polarizers is to use linear polarizing sheets on light sources for copy stand work.

User ID

burkphoto wrote:

A circular polarizer is not circular because it is round. It is 'circular' because of what it does to the light. Circular polarization is needed for digital photography because of the way that most common digital sensors work.

Need of CPLs has NOTHING to do with digital imaging sensors. There are no beam splitters or half mirrors involved with the imaging sensor.

If youre referring to the SLR metering and AF modules which are NOT on the image sensor, yes, those would need CPLs. But those items are not usually called "sensors".

~~~~~~~~~~~~~~~~~~~~~~

You can put an old linear PL on any complex modern SLR and it shoots perfectly well, but youll hafta input exposure and focus by use of eyes, fingers, and experience. The image sensor will do its job regardless.

Ednsb Loc: Santa Barbara

User ID wrote:

Cokins suggestion that their smaller sizes are not for lenses less than about 28mm is obsolete as concerns EVF cameras. The problem was related to the design of SLR wide angle lenses.

OTOH I hope your 16/2.8 has internal, or rear, focusing. If its unit focusing I would hesitate to hang a Cokin system on a tiny STM focus motor meant to drive a tiny lens barrel. My tiny 16/2.8 Sony has IF and theres no problem with large front mounted accessories. Hopefully likewise with your Canon 16.

It doesn't and I hadn't thought of that but it hasn't been mentioned in all of the articles I've read.

burkphoto Loc: High Point, NC

User ID wrote:

Need of CPLs has NOTHING to do with digital imagin... (show quote)

Thanks for clearing up my misunderstanding. I knew there was a reason we all bought CPLs when dSLRs came out... So it's dSLR metering systems that don't work with standard polarizers. I'd been told it was the sensor having a Bayer array.

I'll have to try my old film polarizer on my mirrorless. It did work fine with TTL metering on my Canon and Nikon film cameras.

jcboy3

burkphoto wrote:

Thanks for clearing up my misunderstanding. I knew there was a reason we all bought CPLs when dSLRs came out... So it's dSLR metering systems that don't work with standard polarizers. I'd been told it was the sensor having a Bayer array.

I'll have to try my old film polarizer on my mirrorless. It did work fine with TTL metering on my Canon and Nikon film cameras.

It is because of the mirror.

User ID

burkphoto wrote:

Thanks for clearing up my misunderstanding. I knew there was a reason we all bought CPLs when dSLRs came out... So it's dSLR metering systems that don't work with standard polarizers. I'd been told it was the sensor having a Bayer array.

I'll have to try my old film polarizer on my mirrorless. It did work fine with TTL metering on my Canon and Nikon film cameras.

"Need" of CPLs dates before digital (since its not about the sensor). IIRC correctly it all began with the beam splitter for the metering in the FTb and F1. If using a linear PL you had to set it to horizontal to get an accurate reading and then reset it it for your pictorial effect. This wasnt a huge problem with match needle manual metering but wasnt really agreeable will full AE models that arrived later. And then came AF, rendering the CPL de rigueur.

Ednsb Loc: Santa Barbara

TriX wrote:

I paid a a total of $170 (which included tax and free shipping) for 8 B&W F Pro MRC Nanos - 4 77mms, 2 72s a 62, and a 58. All UVs or clear @ $18-24 each. NDs, if they have them are not a lot more, but CPs are more expensive and not many graduated NDs available. Several were new in boxes, and the rest looked new. They get lots of clear and UVs on lens trades, so those are a bargain.

thank you

User ID

jcboy3 wrote:

It is because of the mirror.

Indirectly so. PLs have zero effect on the mirror. But eliminating THE mirror gets rid of the beam splitters that feed the metering and AF module. Linear PLs are not agreeable with all that stuff. But The Mirror that makes an SLR an SLR does NOT require a CPL.

jcboy3

User ID wrote:

Indirectly so. PLs have zero effect on the mirror. But eliminating THE mirror gets rid of the beam splitters that feed the metering and AF module. Linear PLs are not agreeable with all that stuff. But The Mirror that makes an SLR an SLR does NOT require a CPL.

The mirror is the beam splitter in a DSLR.