Bands with polarizer filter

[brent8927]

I've been noticing some weird vertical bands with shots of the water taken with my polarizing filter. I'm wondering if anyone knows what the issue here is (ie., is it technique, equipment, or just natural phenomena).

For reference, I'm shooting with a Hasselblad, using the Hasselblad linear polarizing filter. The shot below is on B&W film (Delta 400), but I see the same issue when I shoot with my CFV back. I haven't noticed banding (not sure if this is the proper term...) with other shots taken with the polarizing filter (ie., windows, etc.), but I don't use it that much anyway.

I did happen to drop the filter in the Merced River a number of years ago. I didn't (and still don't) notice any problems with the filter visually after it dried out.

 

[moto-uno]

^I'm not seeing the "shot below" . Peter

 

[Sirius Glass]

I cannot see the shot below. Below what?

 

[brent8927]

Whoops! Here's the photo. It's an unedited scan, but you can see the vertical shadowing/banding. They are not reflections/shadows of something on the shore--this photo is of the Puget Sound and the opposing shore is very far away.

 

[brent8927]

Anyone have any ideas?

 

[shutterfinger]

What type of day/lighting when the streaks appear? Bright sun/crystal clear, bright sun/hazy, fogy, overcast, sun shinning through patchy clouds.

 

[Poisson Du Jour]

Possible condensation within the filter from the earlier drop, but it seems very unlikely; B+W filters are extremely well protected where the polariser sheet is sandwiched to the glass plates and sealed. I have been using B+W KSM polarisers for decades (they are also occasionally washed) and never have anything to report about faults that could be attributed to them.

 

[brent8927]

What type of day/lighting when the streaks appear? Bright sun/crystal clear, bright sun/hazy, fogy, overcast, sun shinning through patchy clouds.

Bright sun--close to crystal clear. Shot is aimed west-ish

 

[hsandler]

I have seen this kind of thing sometimes in non-polarizer shots in large uniform areas, like sky, and I think it may not be anything to do with the optical conditions. It may be patterns of turbulence in development agitation. When I switched from a development tank with only rotary agitation to a Patterson tank with agitation by inversion, it went away.

 

[brent8927]

Possible condensation within the filter from the earlier drop, but it seems very unlikely; B+W filters are extremely well protected where the polariser sheet is sandwiched to the glass plates and sealed. I have been using B+W KSM polarisers for decades (they are also occasionally washed) and never have anything to report about faults that could be attributed to them.

Mine is a Hasselblad-brand filter, but I believe those are made by either B+W or Heliopan.

Also, I didn't clarify in my original post, but these bands/shadow areas are present on the film.

 

[brent8927]

I have seen this kind of thing sometimes in non-polarizer shots in large uniform areas, like sky, and I think it may not be anything to do with the optical conditions. It may be patterns of turbulence in development agitation. When I switched from a development tank with only rotary agitation to a Patterson tank with agitation by inversion, it went away.

I had considered that as well, but as best as I can tell no other shots have these same markings (no other shots on that roll of film were taken with the polarizing filter). I have also seen these bands show up on some shots taken on a different day with a CFV back. I do have quite a few rolls of portra taken the same day as the B&W image above that are awaiting development--I am nervous to see what they have in store for me as the bulk of my photos taken that day were of my son playing in the Sound and I imagine they'll be the nicer/more memorable photographs.

Also, just to clarify my development process, I use a Patterson tank with agitation by inversion. Film was developed in DDX. Ilford fixer used. I don't use stop bath (I haven't since about 2008), and instead do a water rinse. Film is Delta 400.

 

[Paul Manuell]

I've been noticing some weird vertical bands with shots of the water taken with my polarizing filter. I'm wondering if anyone knows what the issue here is (ie., is it technique, equipment, or just natural phenomena).

For reference, I'm shooting with a Hasselblad, using the Hasselblad linear polarizing filter. The shot below is on B&W film (Delta 400), but I see the same issue when I shoot with my CFV back. I haven't noticed banding (not sure if this is the proper term...) with other shots taken with the polarizing filter (ie., windows, etc.), but I don't use it that much anyway.

I did happen to drop the filter in the Merced River a number of years ago. I didn't (and still don't) notice any problems with the filter visually after it dried out.

I might be wrong, but shouldn't you be using a circular polariser, not a linear one, or is that just for digital sensors?

 

[brent8927]

I might be wrong, but shouldn't you be using a circular polariser, not a linear one, or is that just for digital sensors?

I believe a linear polarizer is ok because that's what the Hasselblad-branded filter is. However, in the past I remember buying a circular polarizer so I could use the same one with a digital Minolta SLR and with my Hasselblad. But I thought maybe it was the autofocus that needed the circular polarizer? I will need to check into that though since if I use a polarizing filter, it's typically with color, and more of my color shots these days are with the CFV.

 

[abruzzi]

Linear polarizer can potentially mess with auto focus systems and some in-body meters, but if properly focused and exposed shouldn’t have any different effect on the image than a circular polarizer.

 

[brent8927]

Linear polarizer can potentially mess with auto focus systems and some in-body meters, but if properly focused and exposed shouldn’t have any different effect on the image than a circular polarizer.

Thanks--I just looked it up and saw the same thing. It sounds like I can use whichever filter I want since I don't have autofocus or a meter (I use a 501c)

 

[Sirius Glass]

Linear polarizer can potentially mess with auto focus systems and some in-body meters, but if properly focused and exposed shouldn’t have any different effect on the image than a circular polarizer.

Yes. I now buy circular polarizers to avoid problems with the light meters, built in and 45 degree PME.

 

[shutterfinger]

Being the bands only occur with this polarizer regardless of recording medium used I would borrow/rent/buy a different polarizer and give it a try.

 

[brent8927]

Being the bands only occur with this polarizer regardless of recording medium used I would borrow/rent/buy a different polarizer and give it a try.

Yes, I agree that's the best solution. But I'm also curious to see if anyone recognizes this problem first-hand

 

[jerrybro]

It does have the look of interference fringes from 2 flat surfaces with a slight wedge in between them.