Yellowed Lens vs. B&W RAW Images

**JoelA** · 03-12-2023, 01:56 PM

Brain Trust,

I was lucky enough to acquire a beautiful Super-Tak 50 f/1.4 (sn# 3105659).

It's well-yellowed and in amazing condition. Think about a perfectly aged bottle of wine from a long undisturbed cellar! It's a lovely copy.

Both RAW and .jpeg color rendition is exactly what one might hope it would be. Shooting on a K-1 II body.

What I'm perplexed about and would love some input is the black and white rendering from a yellowed lens on a digital camera.

I'm super used to working with yellow filters on black and white film.

But...I'm just not seeing much difference on digital B&W RAW or .jpeg vs. an un-yellowed lens. I've tried the B&W preprogrammed setting as well as my custom "user" setting.

I did a side by side with the Super Tak 50 f/1.4 vs. a K 50 f/1.2 both at f/8 in bright sun with various colors plants and a clear blue sky. And also a portrait of my wife (under duress!!). Just not seeing much difference in B&W digital. Even tried a K-50. Same.

Is there something I'm doing wrong? Or is this something to do with the RAW process itself?

Or am I going blind???

Scratching head in Florida!

Thanks!

Joel

**UncleVanya** · 03-12-2023, 02:38 PM

Originally posted by JoelA

Brain Trust,

I was lucky enough to acquire a beautiful Super-Tak 50 f/1.4 (sn# 3105659).

It's well-yellowed and in amazing condition. Think about a perfectly aged bottle of wine from a long undisturbed cellar! It's a lovely copy.

Both RAW and .jpeg color rendition is exactly what one might hope it would be. Shooting on a K-1 II body.

What I'm perplexed about and would love some input is the black and white rendering from a yellowed lens on a digital camera.

I'm super used to working with yellow filters on black and white film.

But...I'm just not seeing much difference on digital B&W RAW or .jpeg vs. an un-yellowed lens. I've tried the B&W preprogrammed setting as well as my custom "user" setting.

I did a side by side with the Super Tak 50 f/1.4 vs. a K 50 f/1.2 both at f/8 in bright sun with various colors plants and a clear blue sky. And also a portrait of my wife (under duress!!). Just not seeing much difference in B&W digital. Even tried a K-50. Same.

Is there something I'm doing wrong? Or is this something to do with the RAW process itself?

Or am I going blind???

Scratching head in Florida!

Thanks!

Joel

What white balance are you using?

**JoelA** · 03-12-2023, 02:43 PM

I'm using "AWB" - Auto white balance for both the color and black and white program as well as the custom B&W mode.

Joel

**UncleVanya** · 03-12-2023, 02:47 PM - **5 Likes**

Originally posted by JoelA

I'm using "AWB" - Auto white balance for both the color and black and white program as well as the custom B&W mode.

Joel

It’s likely that awb is adjusting the balance of colors in a way that is minimizing the difference. If you pick a specific color balance you may see a difference I’m not sure.

**Bob 256** · 03-12-2023, 07:43 PM - **2 Likes**

What UncleVanya said.

Your AWB is effectively placing a bluish filter in front of your lens which nulls out the yellow, making your lens a weak neutral density filter (in addition to being a lens). The net (jpg) image captured is a normal color image (though probably using a slightly higher exposure value than a non-yellowed lens). Converting that to B&W will have the same effect as converting any normal color image to B&W. The yellowing effect may show up in a RAW file since AWB hasn't been applied to it, but once RAW is converted to JPG, the yellow of the lens has been compensated for by the AWB process. A RAW viewer may also apply AWB before you see the image on-screen.

The best way to get yellow type filtering with a digital camera is in post processing. If you control the mix of the color channels, you can get a good representation of using a yellow filter in a B&W final image. Adobe Photoshop has a color mixer/B&W converter as do many other post processing programs. You can also control the color channel mix if using a RAW file in most RAW processors (e.g., RawTherapee) but you may need a followup program to convert that image to B&W.

You could put a yellow filter over the lens and use a Daylight white balance which should result in a yellowish image and that should convert to a B&W with yellow filter effects as expected, but it's usually easier to use post, and post allows you to explore other color mixes (you can also see the B&W result in real-time instead of waiting for the conversion of an off-color image). You can simulate a range of color filters, but there are still a few that you just can't replicate in post (polarizer, infrared, and narrow band).

Good deal on that Super-Tak though and good shooting with it.

vonBaloney · 03-12-2023, 09:32 PM

The only real effect of using a yellowed lens on digital is that it is less sharp than if you de-yellowed it. (Yes, that makes it a bit sharper -- gets the wavelengths matched up again.) Not sure why you'd want it to remain yellow.

**GUB** · 03-12-2023, 09:53 PM - **1 Like**

Originally posted by vonBaloney

The only real effect of using a yellowed lens on digital is that it is less sharp than if you de-yellowed it. (Yes, that makes it a bit sharper -- gets the wavelengths matched up again.) Not sure why you'd want it to remain yellow.

I did a thread on this - I couldn't identify any softness in the yellow tak.
So should I bleach my 50s - PentaxForums.com

**JoelA** · 03-13-2023, 04:11 AM - **1 Like**

Thank you all so very much for the coaching!

I'm just a darkroom rat, trying to find my way in this digital world.

vonBaloney · 03-13-2023, 09:57 AM

Originally posted by GUB

I did a thread on this - I couldn't identify any softness in the yellow tak.
So should I bleach my 50s - PentaxForums.com

If you do a before and after with the same lens under the same conditions you'll see the difference (how much depends on how yellow it was, but yeah it isn't going to be radical, but it is noticeable). If you like them yellow, sure leave them yellow. But in this day and age where we can adjust colors to our hearts content after the fact (as well as softening, etc), I'd rather have the ability to have the greater sharpness and contrast (as designed), especially when shooting at large apertures where it is going to be a bit softer anyway.

kypfer · 03-13-2023, 03:42 PM

The concept of using analogue b&w correction filters on a digital camera has interested me for several years … even made a few exposures this afternoon through an orange filter.
Then it struck me … conventional analogue b&w film is excessively blue sensitive, hence the advantage of using a yellow (or darker) filter to darken the blue sky, with little or no deep (infra) red sensitivity, whereas digital cameras are inherently deep red and infra-red sensitive (to varying degrees) but not much so at the blue end of the spectrum.
Therefore analogue filter correction simply can't apply to digital cameras in the same way

As to how this relates to a "yellowed" lens I don't know, none of my Super Takumars (or any of my third-party lenses) have this symptom, so even though I'm currently having a "film renaissance", having finished the first roll of film in my Spotmatic this afternoon (the negs look good, I'll be scanning them tomorrow), I can't report on any performance issues

03-12-2023, 01:56 PM	#1
JoelA Loyal Site Supporter Join Date: Feb 2019 Location: Florida Photos: Gallery Posts: 187	Yellowed Lens vs. B&W RAW Images Brain Trust, I was lucky enough to acquire a beautiful Super-Tak 50 f/1.4 (sn# 3105659). It's well-yellowed and in amazing condition. Think about a perfectly aged bottle of wine from a long undisturbed cellar! It's a lovely copy. Both RAW and .jpeg color rendition is exactly what one might hope it would be. Shooting on a K-1 II body. What I'm perplexed about and would love some input is the black and white rendering from a yellowed lens on a digital camera. I'm super used to working with yellow filters on black and white film. But...I'm just not seeing much difference on digital B&W RAW or .jpeg vs. an un-yellowed lens. I've tried the B&W preprogrammed setting as well as my custom "user" setting. I did a side by side with the Super Tak 50 f/1.4 vs. a K 50 f/1.2 both at f/8 in bright sun with various colors plants and a clear blue sky. And also a portrait of my wife (under duress!!). Just not seeing much difference in B&W digital. Even tried a K-50. Same. Is there something I'm doing wrong? Or is this something to do with the RAW process itself? Or am I going blind??? Scratching head in Florida! Thanks! Joel

03-12-2023, 07:43 PM - 2 Likes	#5
Bob 256 Site Supporter Join Date: Jun 2008 Location: Idaho Photos: Gallery Posts: 2,378	What UncleVanya said. Your AWB is effectively placing a bluish filter in front of your lens which nulls out the yellow, making your lens a weak neutral density filter (in addition to being a lens). The net (jpg) image captured is a normal color image (though probably using a slightly higher exposure value than a non-yellowed lens). Converting that to B&W will have the same effect as converting any normal color image to B&W. The yellowing effect may show up in a RAW file since AWB hasn't been applied to it, but once RAW is converted to JPG, the yellow of the lens has been compensated for by the AWB process. A RAW viewer may also apply AWB before you see the image on-screen. The best way to get yellow type filtering with a digital camera is in post processing. If you control the mix of the color channels, you can get a good representation of using a yellow filter in a B&W final image. Adobe Photoshop has a color mixer/B&W converter as do many other post processing programs. You can also control the color channel mix if using a RAW file in most RAW processors (e.g., RawTherapee) but you may need a followup program to convert that image to B&W. You could put a yellow filter over the lens and use a Daylight white balance which should result in a yellowish image and that should convert to a B&W with yellow filter effects as expected, but it's usually easier to use post, and post allows you to explore other color mixes (you can also see the B&W result in real-time instead of waiting for the conversion of an off-color image). You can simulate a range of color filters, but there are still a few that you just can't replicate in post (polarizer, infrared, and narrow band). Good deal on that Super-Tak though and good shooting with it. Last edited by Bob 256; 03-12-2023 at 08:02 PM.

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03-12-2023, 02:38 PM	#2
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,459	Originally posted by JoelA Brain Trust, I was lucky enough to acquire a beautiful Super-Tak 50 f/1.4 (sn# 3105659). It's well-yellowed and in amazing condition. Think about a perfectly aged bottle of wine from a long undisturbed cellar! It's a lovely copy. Both RAW and .jpeg color rendition is exactly what one might hope it would be. Shooting on a K-1 II body. What I'm perplexed about and would love some input is the black and white rendering from a yellowed lens on a digital camera. I'm super used to working with yellow filters on black and white film. But...I'm just not seeing much difference on digital B&W RAW or .jpeg vs. an un-yellowed lens. I've tried the B&W preprogrammed setting as well as my custom "user" setting. I did a side by side with the Super Tak 50 f/1.4 vs. a K 50 f/1.2 both at f/8 in bright sun with various colors plants and a clear blue sky. And also a portrait of my wife (under duress!!). Just not seeing much difference in B&W digital. Even tried a K-50. Same. Is there something I'm doing wrong? Or is this something to do with the RAW process itself? Or am I going blind??? Scratching head in Florida! Thanks! Joel What white balance are you using?

03-12-2023, 02:43 PM	#3
JoelA Loyal Site Supporter Join Date: Feb 2019 Location: Florida Photos: Gallery Posts: 187 Original Poster	I'm using "AWB" - Auto white balance for both the color and black and white program as well as the custom B&W mode. Joel

03-12-2023, 02:47 PM - 5 Likes	#4
UncleVanya Loyal Site Supporter Join Date: Jul 2014 Photos: Gallery \| Albums Posts: 28,459	Originally posted by JoelA I'm using "AWB" - Auto white balance for both the color and black and white program as well as the custom B&W mode. Joel It’s likely that awb is adjusting the balance of colors in a way that is minimizing the difference. If you pick a specific color balance you may see a difference I’m not sure.

03-12-2023, 09:32 PM	#6
vonBaloney Pentaxian Join Date: Oct 2011 Location: Albuquerque, NM Posts: 6,029	The only real effect of using a yellowed lens on digital is that it is less sharp than if you de-yellowed it. (Yes, that makes it a bit sharper -- gets the wavelengths matched up again.) Not sure why you'd want it to remain yellow.

03-12-2023, 09:53 PM - 1 Like	#7
GUB Loyal Site Supporter Join Date: Aug 2012 Location: Wanganui Photos: Gallery \| Albums Posts: 5,760	Originally posted by vonBaloney The only real effect of using a yellowed lens on digital is that it is less sharp than if you de-yellowed it. (Yes, that makes it a bit sharper -- gets the wavelengths matched up again.) Not sure why you'd want it to remain yellow. I did a thread on this - I couldn't identify any softness in the yellow tak. So should I bleach my 50s - PentaxForums.com

03-13-2023, 04:11 AM - 1 Like	#8
JoelA Loyal Site Supporter Join Date: Feb 2019 Location: Florida Photos: Gallery Posts: 187 Original Poster	Thank you all so very much for the coaching! I'm just a darkroom rat, trying to find my way in this digital world.

03-13-2023, 09:57 AM	#9
vonBaloney Pentaxian Join Date: Oct 2011 Location: Albuquerque, NM Posts: 6,029	Originally posted by GUB I did a thread on this - I couldn't identify any softness in the yellow tak. So should I bleach my 50s - PentaxForums.com If you do a before and after with the same lens under the same conditions you'll see the difference (how much depends on how yellow it was, but yeah it isn't going to be radical, but it is noticeable). If you like them yellow, sure leave them yellow. But in this day and age where we can adjust colors to our hearts content after the fact (as well as softening, etc), I'd rather have the ability to have the greater sharpness and contrast (as designed), especially when shooting at large apertures where it is going to be a bit softer anyway.

03-13-2023, 03:42 PM	#10
kypfer Pentaxian Join Date: Jan 2018 Location: Jersey C.I. Posts: 3,596	The concept of using analogue b&w correction filters on a digital camera has interested me for several years … even made a few exposures this afternoon through an orange filter. Then it struck me … conventional analogue b&w film is excessively blue sensitive, hence the advantage of using a yellow (or darker) filter to darken the blue sky, with little or no deep (infra) red sensitivity, whereas digital cameras are inherently deep red and infra-red sensitive (to varying degrees) but not much so at the blue end of the spectrum. Therefore analogue filter correction simply can't apply to digital cameras in the same way As to how this relates to a "yellowed" lens I don't know, none of my Super Takumars (or any of my third-party lenses) have this symptom, so even though I'm currently having a "film renaissance", having finished the first roll of film in my Spotmatic this afternoon (the negs look good, I'll be scanning them tomorrow), I can't report on any performance issues