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Greetings from Portugal!

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#81 ACRosalino

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Posted 31 March 2019 - 16:22

Andy, may I ask which uv/ir block filter are you using with your A7S for 'normal' daylight photography?
António C. Rosalino
Some UV permeable old glass: EL-Nikkor "metallic" 80mm & 105mm f/5.6, Steinheil Cassar-S 50mm f/2.8, Auto Exaktar 35mm f/2.8
Some UV lights: 2x Canon Speedlite 199A, waiting to be modified, ‘naked conversion’ Sony a7III, Baader-U 2” filter, no UV photos... yet.

#82 Andy Perrin

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Posted 31 March 2019 - 20:22

Sometimes BG38 2mm, sometimes Hoya UVIR cut. Not 100% satisfied with either, however. BG38 does not cut UV much, and the Hoya has cutoffs that are too far into UV also, but more red.

#83 Cadmium

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Posted 01 April 2019 - 05:42

Does BG38 look too red or too blue? You do a custom white balance or white balance from RAW?

#84 Andy Perrin

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Posted 01 April 2019 - 14:17

My BG38 tends to have too little red IiRC, but I should take a daylight photo and check. I usually WB in camera using Teflon.

#85 Cadmium

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Posted 01 April 2019 - 21:07

If it looks too red, then maybe you should used BG40, would trade you even.
Here is how it works for me:
Bluer - S8612 - BG39 - BG40 - BG38 - Baader UV/IR-Cut - Redder
(the S8612 and BG39 look the same to me)
Many people like BG40, depends on Camera a little.
However, there is no perfect replacement filter for whatever was originally internal. One size doesn't fit all,
however white balance can be helpful.
Not telling you this about white balance, Andy, just for others.

Edited by Cadmium, 01 April 2019 - 21:09.


#86 ACRosalino

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Posted 04 April 2019 - 18:54

So... if I understood it correctly: Andy's A7S with BG38 displays not enough reds, therefore, a filter like Baader UV/IR could work better (as it lets through more red)?
António C. Rosalino
Some UV permeable old glass: EL-Nikkor "metallic" 80mm & 105mm f/5.6, Steinheil Cassar-S 50mm f/2.8, Auto Exaktar 35mm f/2.8
Some UV lights: 2x Canon Speedlite 199A, waiting to be modified, ‘naked conversion’ Sony a7III, Baader-U 2” filter, no UV photos... yet.

#87 Andy Perrin

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Posted 05 April 2019 - 00:43

Yeah hold up on that — I realized that I haven’t done a systematic test on my A7S. The conclusion that it leans toward blue was from my NEX-7 before I upgraded. So I actually need to do a check. I’ve been swamped with work lately so it’s going to have to wait a little.

#88 ACRosalino

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Posted 09 October 2019 - 22:30

Andy, may I ask again about your experience with the a7s - have you found the ‘ideal’ filter to restore normal color balance?

I have just received my a7iii back from its ‘naked conversion’ surgery and I expect to try it soon with the Baader U filter...

And I also need a couple of IR filters... all this can get really expensive, fast :-)
António C. Rosalino
Some UV permeable old glass: EL-Nikkor "metallic" 80mm & 105mm f/5.6, Steinheil Cassar-S 50mm f/2.8, Auto Exaktar 35mm f/2.8
Some UV lights: 2x Canon Speedlite 199A, waiting to be modified, ‘naked conversion’ Sony a7III, Baader-U 2” filter, no UV photos... yet.

#89 Andy Perrin

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Posted 10 October 2019 - 01:11

Antonio- ideal? Well not 100% but my eyesight is not 100% either. (Color deficiency in red/green.) If I stick 2mm BG38 on there it’s reasonably close and you can adjust the colors with a profile in PhotoNinja, assuming you can see them properly in the first place... I have to admit, perfect color is not something I care about in my photography for reasons that should now be obvious!