Debayered cameras?

[TiCoyote]

I've been enjoying shooting B&W film, but I wonder if I can get better results with less time/effort/money in digital. Shooting digital and then converting to B&W has some drawbacks. You can't use a red filter. You can PP a red filter, but it's not quite... the same.

There's the Leica Monochrom, but it's pricey.

I was thinking about buying a used 5D2, and sending it off to one of these companies that removes the low-pass AA filter and also removes the Bayer array.

Does anyone here have any experiences with this or thoughts?

 

[jcdeboever]

I've been enjoying shooting B&W film, but I wonder if I can get better results with less time/effort/money in digital. Shooting digital and then converting to B&W has some drawbacks. You can't use a red filter. You can PP a red filter, but it's not quite... the same.

There's the Leica Monochrom, but it's pricey.

I was thinking about buying a used 5D2, and sending it off to one of these companies that removes the low-pass AA filter and also removes the Bayer array.

Does anyone here have any experiences with this or thoughts?

Personally, I have done a great deal of research on this both physically and carefully (internet). Fujifilm appears to be light years ahead of everyone else on film simulation mode inside the camera. Not sure your budget but you want to look at the X-series. I brought a card into a store and played around with the X100T and the X-T2. Pretty darn close to film, I love the Acros film simulation, just wonderful. I really liked the image quality of both models. The X100T and soon to be F are classic retro film camera styling. The X-70 is nice too if your on a budget. X-70 and X100T are fixed lens cameras and the X-T2 has a full lens lineup, their primes are outstanding. I wish I never would have touched them because I want one pretty bad.

This guy is straight up and was a hardcore canon user.....

 

[petrochemist114 139]

You can PP a red filter, but it's not quite... the same.

It's not the same, no it's much better!
With Silver Effects Pro you can easily adjust to just the right amount of red/yellow filtration for the result you want, much better than carrying 4+ filters. If required you can even use different filters for different parts of the image e.g. green for skin tone & red for the sky.

There's so much control available in producing a B&W image from a color file I can't see why anyone would want a B&W only camera. Even with a 720nm IR filter fitted I have useful data in the color channels that can be used to tweak how a B&W image looks.

I use filters quite a lot on my converted camera as they make big differences when IR is included in the mix. I can't see any reason why you couldn't use a red filter on a standard digital camera. You might have to be careful with your metering, but otherwise there shouldn't be any issues.

I suspect removing the Bayer array from a camera will make the file formats difficult to work with, you would need a custom RAW converter...

 

[john.margetts]

You can PP a red filter, but it's not quite... the same.

It's not the same, no it's much better!
With Silver Effects Pro you can easily adjust to just the right amount of red/yellow filtration for the result you want, much better than carrying 4+ filters. If required you can even use different filters for different parts of the image e.g. green for skin tone & red for the sky.

There's so much control available in producing a B&W image from a color file I can't see why anyone would want a B&W only camera. Even with a 720nm IR filter fitted I have useful data in the color channels that can be used to tweak how a B&W image looks.

I use filters quite a lot on my converted camera as they make big differences when IR is included in the mix. I can't see any reason why you couldn't use a red filter on a standard digital camera. You might have to be careful with your metering, but otherwise there shouldn't be any issues.

I suspect removing the Bayer array from a camera will make the file formats difficult to work with, you would need a custom RAW converter...

If using Silver Effects Pro software is so much better than using filters, why are you using filters 'quite a lot'?

As for removing the Bayer array, Raw conversion would not be required as the image is not mosaiced - so cannot be demosaiced.

 

[480sparky37 36]

You can PP a red filter, but it's not quite... the same.

It's not the same, no it's much better!
With Silver Effects Pro you can easily adjust to just the right amount of red/yellow filtration for the result you want, much better than carrying 4+ filters. If required you can even use different filters for different parts of the image e.g. green for skin tone & red for the sky.

There's so much control available in producing a B&W image from a color file I can't see why anyone would want a B&W only camera. Even with a 720nm IR filter fitted I have useful data in the color channels that can be used to tweak how a B&W image looks.

I use filters quite a lot on my converted camera as they make big differences when IR is included in the mix. I can't see any reason why you couldn't use a red filter on a standard digital camera. You might have to be careful with your metering, but otherwise there shouldn't be any issues.

I suspect removing the Bayer array from a camera will make the file formats difficult to work with, you would need a custom RAW converter...

If using Silver Effects Pro software is so much better than using filters, why are you using filters 'quite a lot'?

As for removing the Bayer array, Raw conversion would not be required as the image is not mosaiced - so cannot be demosaiced.

So how does a raw converter "know" this?

How do you not demosaic?

 

[petrochemist114 139]

If using Silver Effects Pro software is so much better than using filters, why are you using filters 'quite a lot'?.

As I mentioned this is with my IR converted camera. The Bayer filter does not have a separate channel for IR, and IR signals show in all 3 channels. Using a red filter I block visible light that would normally go to the B&G channels just leaving the IR parts in those channels. Software is unable to tell witch bits of the signal are from visible & which from IR so it can't replicate this effect.
Likewise a blue filter will give me mainly Blue, IR & maybe some UV, while blocking R&G. Again the IR shows in all channels.
Another favorite is a U330 filter which is visibly opaque, but transmits UV & IR. this tends to give me nice dark blue skies with blue tinged IR like characteristics. like this:
Dovercourt park IR by Mike Kanssen, on Flickr

Without a filter at all this camera generally produces images which can at first glimpse look normal like this:
Full Spectrum grid by Mike Kanssen, on Flickr
However the teams uniforms match the car (black not brown) to the eye so IR is effecting things. A filter can block the IR to correct that but it's normally much easier to get out my standard camera instead.

If shoot visual B&W I don't use filters other than perhaps a polarizer or ND.

As Sparky points out, the RAW software is expecting to have to demosaic the image & AFAIK has no routines that avoid these calculations in creating the output.
A programmer with the code for RAW conversion ought to be able to strip those routines and change the working/output arrays to the appropriate new resolution. If the code is well annotated it may even be a fairly trivial exercise. Just having the precompiled software would I expect make the job considerably harder. I suspect the current RAW converter probably uses the separate channels individually for some of noise reduction & sharpening routines as well. If so that may further complicate a Bayer free converter (the custom RAW converter).

 

[unpopular]

I think the raw processor would happily demosaic the image as if all three components had the same signal - just as any grey object would. I don't think the raw processor would throw up, but at the same time I don't think you'd get any real advantage either.

Raw Photo processor on Mac can render images in "half" mode, which basically just stacks the array and results in an image of half the pixel size. Results are very, very good, but obviously come at a cost, and the actual impact on resolution is pretty minimal with color rendering and sharpness being most affected.

I'd imagine though that there must be software out there that will convert a raw file directly to an image file without any processing. I've seen images of what a raw file looks like straight out of the camera, though I don't know how they produced it.

But moreso, is removing the filter even possible? I've always been under the impression that the filter is integrated into the sensor itself, leaving me to question if all they're really doing is some kind of firmware modification to force it into spitting back b/w images. I am not sure if that is even possible or not, though if they will only do this on canon cameras, that should be a good indicator since Canon firmware has already been hacked and is pretty well documented.

I would be pretty skeptical of this service, personally.

 

[unpopular]

And yes, there is real advantage to using optical filters, though I don't necessarily believe it's the quality. Rather using them increases exposure rather than pushing channel data - which is already pushed pretty hard in white balance. So assuming you use the same gain on both, you should have less noise liability when using an optical filter.

That said, though, this can be easily overshadowed by the flexibility of using the channel mixer or any other means to get the effect in post.

Certainly, though there are going to be conversion issues when using an optical filter, and simply selecting 'greyscale' on your camera won't necessarily give you the result you're after.

 

[Ysarex83 77]

I'd imagine though that there must be software out there that will convert a raw file directly to an image file without any processing. I've seen images of what a raw file looks like straight out of the camera, though I don't know how they produced it.

RawDigger and RawTherapee will both allow you to pull the image without demosaicing the CFA. What you can do with it at that point is pretty much restricted to showing off the result for the benefit of instruction. Post processing is needless to say pretty limited.

Here's a B&W photo processed from an undemosaiced raw file.

The CFA pattern can't be removed but it can be disguised with a very heavy grain simulation. (I develop my Tri-X in heated Rodinal).

Joe

 

[unpopular]

@Ysarex - Interesting.

I am assuming that the pattern is resulting from difference in color across the filtered regions?

Provided that you could compensate for the filter factor of each component, which should be similar, I wonder if you could use the lightness channel to produce an image without the pattern.

 

[480sparky37 36]

........ RawTherapee will both allow you to pull the image without demosaicing the CFA. ..........

Care to spill the beans on how to do this? I can't find anything in either V2.4 or 4.1.

 

[Derrel]

I've been enjoying shooting B&W film, but I wonder if I can get better results with less time/effort/money in digital. Shooting digital and then converting to B&W has some drawbacks. You can't use a red filter. You can PP a red filter, but it's not quite... the same.

Better results? Most likely. Less time? Heck yes, wayyyy less time. Less effort? Oh, my YES, much less effort. The Canon .CR2 files are FULL-COLOR, so you have a full-color, full bit depth .CR2 as well as the camera-created B&W image.

No need to remove the AA filter. I think you want the camera "stock". Set it to shoot RAW + JPEG. Set the color toning as you like: I like Canon's sepia tone look for my RAW + JPEG B&W. Shoot either large, fine JPEGs, or reduced them in size, but keep the fine compression.

You get to PICK Plus OR Minus Development, as needed!!! Soo nice! You can adjust sharpening as-needed. You have a filter kit, in button controls! For EVERY single filter size! 82,77,72,58,52...you're set on filters!

Set the filter effect to Yellow for a standard, accepted baseline rendering of the large things like blues, greens, reds, and flesh-tones. or, pick another filter, for different looks on the JPG file.

Options of filters are None, Yellow,Orange,Red,Green.

Toning Effect:None,Sepia,Blue,Purple,Green. (I prefer Sepia, but None is also nice: Neutral-tone B&W paper/developer effect.

Set your Parameters Set for the right Contrast, Sharpness, Saturation, and Color one. (Canon''s categories
********
Canon has this ALLLLLLL figured out for you. My ancient POS Canon 20D's images look as good as Plus-X Pan 125, or T-Max 100. Easily as good as 35mm from a what? A 12 year-old mid-priced APS-C sensor camera.
*******

I might be the only person on TPF who advocates this method...you know, actually USING the system those 50 Canon engineers debveloped to shoot perfect SOOC B&W images...with adjustable filter, adjustable contrast levels, adjustable sharpening, adjustable paper/developer toning look,and the right tonal representations that look like file types of filtration.

DOWN-sizing a big image tends to suppress noise' the ancient Nikon D1 made a gorgeous in-camera Medium B&W Jpeg from its noisy 2.7-MP sensor; you're talking Canon 5D II or III--much newer,larger,bigger,better sensor!

You wonder if you can, "can get better results with less time/effort/money in digital". Canon developed a system to do just that.

 

[Ysarex83 77]

........ RawTherapee will both allow you to pull the image without demosaicing the CFA. ..........

Care to spill the beans on how to do this? I can't find anything in either V2.4 or 4.1.

Oops, sorry.

In RT first go to color management and select No profile. You may also want to go down and check Free Gamma and set that to 1.00 and zero the slope. Then go to the Raw tab and under Sensor with _____ matrix select none in the drop box.

Process and you'll get an image with the CFA still in place.

Joe

edit: I'm using version 4.2. Early versions didn't include the none option in that drop list but in that case just close RT, find the .PPx file and open in a text editor. Toward the end of the file you'll see an entry for demosaic = and change what's there to 0. Save the file and then re-open RT, select the image and process without making any other changes.

 

[Ysarex83 77]

@Ysarex - Interesting.

I am assuming that the pattern is resulting from difference in color across the filtered regions?

Provided that you could compensate for the filter factor of each component, which should be similar, I wonder if you could use the lightness channel to produce an image without the pattern.

Yep, that's the pattern source alright and good luck finding a way to remove it. If you do I'd like to know. Here's a dropbox link to that photo above with the CFA fully in place: raw_photo

Joe

 

[480sparky37 36]

........ RawTherapee will both allow you to pull the image without demosaicing the CFA. ..........

Care to spill the beans on how to do this? I can't find anything in either V2.4 or 4.1.

Oops, sorry.

In RT first go to color management and select No profile. You may also want to go down and check Free Gamma and set that to 1.00 and zero the slope. Then go to the Raw tab and under Sensor with _____ matrix select none in the drop box.

Process and you'll get an image with the CFA still in place.

Joe

We must have different versions. I have no "No Profile", for anything, under Color Management (except for monitor profile which is default None).