Preachdude Loc: Geneva, OH

I make a lot of images in the mountains, particularly in Yosemite and the Sierras. In my film days, I found that using a Haze 1A filter was helpful in some situations. Now that I shoot almost entirely digital, and I don't usually use a haze filter, even for "protection." I understand that the 2A filter removes virtually all UV light, but some complain that it also takes some of the purple as well. For a Zeiss Batis 18mm lens, the filters are 77mm, which can be quite expensive. Tiffen makes a 77mm 2A filter. Does anyone have experience with 2A filters, Tiffen or otherwise?

lamiaceae Loc: San Luis Obispo County, CA

You dont need it digital cameras have UV and IR filter right over the sensor already. that is what is removed when making a converted camera for IR, UV, or both photography. Those old filters are just that for film use with vintage film cameras. Yes, I think I have a couple 2A and 2B wratten gels. Of no use today for digital.

Preachdude Loc: Geneva, OH

Thank you for your reply. Your point is agreed with by many people, but in sample images available on several Internet sites, purple fringing is removed with the 2A filter. The trouble is, all of the examples I've found are city-oriented, where high altitude more intense UV is not an issue. Thanks again for your reply.

bleirer

That's what I used to think, but I'm open to it now in higher altitude shooting after reading some topics here. Apparently some small part of the uv is not blocked by the lens or the sensor filter.

lamiaceae Loc: San Luis Obispo County, CA

But from what I've seen as to any Purple / Yellow fringing is more due to poor lens design. I never see it with my Pentax lenses only off brands. Is 10K feet in the Sierras high enough for you. Different lens designs focus light on to different planes near the sensor. Some only accurately two colors, others three, others more including IR and UV. For IR old vintage lenses had a send focusing mark on the lens barrel. For digital IR a converted camera should have a lens (re)calibrated for only IR use. You may need to use a different lens for normal color. Even WB might shift at high altitudes a little. Though I find I'm usually happy with AWB in day or sun light. Also WA and Teles have more glass to cause more problems.

You realize you can't see UV. And any effect would have to be shifted to one of three color channels, RGB in the camera. There might be a camera brand and model difference. But all my friends with Nikon, Canon, and Pentax cameras never seem to have a complaint.

If you really think you need a #2 filter or even one with more UV cut, look for a used 4" Kodak Wratten Gel Filter. They can be cheap or expensive based on popularity of the filter. I have a couple deep IR gels and I see then costing a bundle today.

Architect1776 Loc: In my mind

I do not know if this is any help but I was shown not long ago here about the haze feature in Photo shop and lightly used removes the slight haze seen in the distance without seeming to affect the color at all.
I like it but I could be wrong but just a thought if that "Haze" is a bit of an issue.

rmcgarry331

The purple fringing you are describing sounds like chromatic aberration, which is an effect produced by the different wavelengths of light failing to focus. It is usually evidenced by green or purple fringing. All lenses will have some degree of CA. Inexpensive lenses are more notorious, but better lenses can still exhibit the problem. Cheap filters will make the problem worse, rather than better.
To reduce CA, always use a lens hood, as side light hitting the front of the lens exacerbates the problem. Camera manufacturers are aware of the problem. If you are shooting JPEGs make sure that lens corrections are turned on in your camera, and the manufactures lens profile is downloaded to your camera. If using third party lenses you are SOL. If shooting RAW, and processing in Lightroom/Adobe Camera RAW, there is a Lens Corrections panel. Make sure profile corrections are turned on, and the appropriate camera/lens is selected. You can also manually defringe from that panel using the eye dropper tool to select the offending shade of purple or green.

racerrich3 Loc: Los Angeles, Ca.

I have lots of Tiffen filters. they ARE good and official filter of NASA so I have heard/read/seen/ whatever.

Architect1776 Loc: In my mind

bleirer

I'm not judging tiffen, but 'official' usually means somebody paid a promotional fee.

Architect1776 Loc: In my mind

Just like NASA using Nikon cameras.

racerrich3 Loc: Los Angeles, Ca.

So? They possibly paid a fee.

bleirer

Im sure they are fine filters, just saying that being official doesn't indicate that nasa has evaluated them and judged them to be the best, just that Tiffen marketing dept. has paid a promotional fee to buy that designation.. Canon will probably be the 'official' camera of the Olympics, but it doesn't mean the Olympic committee is saying they are the best camera, just that they bid the highest.

Architect1776 Loc: In my mind

Is that why virtually all the pros there use Canon?
I thought they used the best in the competitive arena of getting the shot.

bleirer

I think Canon is the best too. But now I'm sorry I mentioned it because people's emotions get churned up over their favorite brands. I was just commenting on being aware of how we are influenced by marketing when we see 'official sponsor' but just pointing out that being the 'official' doesn't prove anything about quality. Gatorade might be the official sports drink of the NFL but that doesn't prove the NFL tested all sports drinks to prove they are the best sports drink.

https://247wallst.com/media/2019/09/12/these-are-the-sponsors-of-the-nfls-100th-anniversary/