I don’t claim to be as technical as many, maybe we can get Jim Kasson or Bill Cliff to do some tests, or other technically minded folks. Anecdotally, I was talking to a gentleman with an A7 monochrome and an A7RII standard and his feeling was that the two were very close in terms of perceived sharpness, which gives somewhat an answer.
grahamgibson wrote:
I think I understand, but I'm not quite sure how much of benefit (quantifiably) a monochrome conversion's increased sensitivity and resolution provide. Do we have a estimated amount? For example, does a monochrome A7r (36M) provide more resolution and/or sensitivity than a A7rII (42MP) image converted to B&W?
Random, related update... I have to admit ACR’s newly released monochrome profiles are intriguing. Plan to play with some Bayer full spectrum files tomorrow. An interesting alternative (at least for me) would be a full spectrum A7RII with the Astronomik clip in filter for visible shots (and generally left in place), and full spectrum for converted b&w shots like I’ve done before and been pleased with. Could also pull the clip in filter and move to a front end Kolari hot mirror filter for ultimate RF wide angle performance for visible light. It’s not monochrome but it’s much less expensive and much more flexible... hmm...
I had a nice back-and-forth email conversation with Daniel from Monochrome Imaging Services this evening. He's going to put up some RAW files we can download and play with that do what I was asking for earlier, i.e., same camera body, same lens, same scene, but one with factory sensor and one with monochrome conversion. I will post the links when he has them ready.
rdeloe wrote:
I had a nice back-and-forth email conversation with Daniel from Monochrome Imaging Services this evening. He's going to put up some RAW files we can download and play with that do what I was asking for earlier, i.e., same camera body, same lens, same scene, but one with factory sensor and one with monochrome conversion. I will post the links when he has them ready.
Speaking of Adobe's new Profiles... I downloaded the A7RII RAW file for the image here to play with: https://www.monochromeimaging.com/sample-galleries/a7r-iim/
If you bring this file directly into Lightroom, you have to drag both Magenta and Purple to -100 (under Hue in Develop). That gives you black and white.
Now, this is where it gets interesting with Version 7.3's Profiles. They all still work... just differently. The various Adobe Raw colour ones give you different kinds of tonality to choose from. The Camera Matching ones do that too, but give you weird results because they play funny with the colour information left behind in Purple and Magenta. Ditto Artistic (strange tinting). But the B&W ones are full of interesting tonality options for people who like "one click" development. The Modern and Vintage profiles also have some interesting Sepia toned results (along with weird purplish tones).
If nothing else it's interesting to see how this all works.
Mathieu18 wrote:
Random, related update... I have to admit ACR’s newly released monochrome profiles are intriguing. Plan to play with some Bayer full spectrum files tomorrow. An interesting alternative (at least for me) would be a full spectrum A7RII with the Astronomik clip in filter for visible shots (and generally left in place), and full spectrum for converted b&w shots like I’ve done before and been pleased with. Could also pull the clip in filter and move to a front end Kolari hot mirror filter for ultimate RF wide angle performance for visible light. It’s not monochrome but it’s much less expensive and much more flexible... hmm......Show more →
The problem with Adobe is that it still demosaics the file, so you’re giving up detail gains. You can just drag the saturation slider to zero as well I believe.
Played with the new profiles, none of them jumped out at me but my own sample raw was a terrible example so I’ll reserve judgement. Will be a bit interesting, if adobe has made good improvements in toning, And I can get full A7RII resolution after all with a better workflow than Silver Efex, it’s not monochrome but still a great option.
rdeloe wrote:
Speaking of Adobe's new Profiles... I downloaded the A7RII RAW file for the image here to play with: https://www.monochromeimaging.com/sample-galleries/a7r-iim/
If you bring this file directly into Lightroom, you have to drag both Magenta and Purple to -100 (under Hue in Develop). That gives you black and white.
Now, this is where it gets interesting with Version 7.3's Profiles. They all still work... just differently. The various Adobe Raw colour ones give you different kinds of tonality to choose from. The Camera Matching ones do that too, but give you weird results because they play funny with the colour information left behind in Purple and Magenta. Ditto Artistic (strange tinting). But the B&W ones are full of interesting tonality options for people who like "one click" development. The Modern and Vintage profiles also have some interesting Sepia toned results (along with weird purplish tones).
If nothing else it's interesting to see how this all works.
I think to get the best resolution, you need to use a RAW converter that can treat the file as truly monochrome otherwise as Mathieu mentions, the demosaicing will mess things up. Monochrome Imaging has a bunch of suggestions on their website for RAW converters that will do this. For users who want to use a particular RAW converter (like Lightroom for me), the monochrome2dng program from the FastRawView people will make a DNG that won't be demosaiced by things like Lightroom but will still give you the latitude of RAW.
That makes sense. I downloaded Monochrome2DNG and converted that same file. It's a very slick tool -- simple and easy to use. After importing the DNG into LR, you are in a world of "monochrome purity". You have exactly one Profile (LR 7.3): 'Monochrome', and of course no colour channels to manipulate.
Interestingly, in quickly comparing the two files (ARW straight into LR with desaturation and DNG converted by Monochrome2DNG) I haven't yet noticed a significant difference in image quality. I was able to find a few small areas in the image where I'd possibly give a slight edge to the monochrome DNG after applying sharpening to both, but what I noticed was only evident at 200% (which for me equates to "not significant" because 200% magnification isn't photographically relevant). In other words, if LR's demosaicing is reducing image quality, it's not obvious to me in this sample ARW file from an A7RII.
To really appreciate this you have to download the file and compare for yourself side-by-side in LR or whatever you use.
This has been an interesting exploration. So far I've taken a few things away from this:
* if you want a very pure monochrome experience, this is the way to go
* the workflow using Monochrome2DNG is very simple
* the A7RII produces a really nice file
* the Micro Nikkor 105/2.8 Daniel used to make that shot is a really nice lens
* and finally, I remain on the fence regarding the benefits.
I'm looking forward to comparing a demosaiced ARW converted to black and white to its monochrome DNG via Monochrome2DNG counterpart.
Andre Y wrote:
I think to get the best resolution, you need to use a RAW converter that can treat the file as truly monochrome otherwise as Mathieu mentions, the demosaicing will mess things up. Monochrome Imaging has a bunch of suggestions on their website for RAW converters that will do this. For users who want to use a particular RAW converter (like Lightroom for me), the monochrome2dng program from the FastRawView people will make a DNG that won't be demosaiced by things like Lightroom but will still give you the latitude of RAW.
Thanks for that, I look forward to seeing the pair of images as well!
FWIW, I just had a chance to compare a few full spectrum bayer filter images with Adobe's new profiles and I'm very impressed. Consistently able to make the whites pop more and get a livelier image. The 10+ starting points (plus color filters which don't work as well on IR polluted photos) were great to pick a base of the image I envisioned and you still have sliders to refine it. Looking at these side by side, it's not like you couldn't get to the second results with a bit more editing, but became quite effortless with the new profiles. Enough so that I'll wait to see the monochrome side by side (and secretly hope I'm convinced) otherwise will just convert my A7RII to bare sensor full spectrum and use a clip in filter for a hot mirror.
While I've committed a camera to full-spectrum monochrome, it's doubtful that it will do much better in visible-light pictorial use than a conventional Bayer camera using carefully chosen B/W conversions. You gain from the absence of the de-Bayering process, but you lose two ways, at least:
1) Filters, whether in front of or behind the lens do slightly reduce definition, especially well off-axis. Astronomik is marketing their filters mostly for telescopic systems which are virtually telecentric, yet many of the conventional camera lenses we will be using have exit pupils much closer to sensor.
2) Lateral chromatic aberration cannot be software-corrected, so it may well be that the narrower UV+IR cut filters offered by Astronomik are preferable, especially the narrowest, L-3.
As to pictorial IR, one eagerly awaits any indication whether there's appreciable pictorial difference between the various IR-pass filters 642, 742 and 807. It's a shame experimentation here is so expensive.
Astronomik offers a clear filter for dust-protection/parfocality, and one has to wonder whether Daniel Morrison is sourcing his cover glass from them: the thickness is the same, 1mm.
That is a really good point. Conversion to B&W in a regular RAW file does mask some CA, but when it's bad it can create an ugly line that isn't easy to remove after conversion. The option to tidy it up before conversion is gone with a monochrome sensor.
AZSteve wrote:
2) Lateral chromatic aberration cannot be software-corrected, so it may well be that the narrower UV+IR cut filters offered by Astronomik are preferable, especially the narrowest, L-3.
It seems to me that the core value proposition of monochrome conversion relates to improved resolution and/or lower sensor noise. To demonstrate it, sample images at small size are nice but may be merely "andecdotal". We need a rigorous apples-to-apples comparison: the identical stationary scene, shot on a tripod, using the same lens at the same f/stop and shutter speed, where the only difference is that one camera has been converted and the other one (the same model) has not.
Perhaps I am mistaken but as with other factors like vibration reduction, the difference may boil down to some factor (like degree of enlargement, higher ISO or deeper underexposure) beyond which the difference becomes perceptible.
Perhaps the difference is only evident at 100% size. Perhaps a converted sensor allows you to print twice as large as you could before, or you get 2 extra stops of usable dynamic range... Whatever it is, I'd love to see the metrics and compelling side-by-side comparisons... in black and white
I asked Daniel from Monochrome Imaging Services about this a while back: I look forward to seeing them.
I'm totally with you on the need for controlled, side-by-side comparison. A few posts earlier in this thread you'll see I promised to post some links to RAW files that will allow us to do that (courtesy of Daniel from Monochrome Imaging Services). Looks like you did too. They're not up yet on Daniel's site, but stay tuned.
Kenneth Lee wrote:
It seems to me that the core value proposition of monochrome conversion relates to improved resolution and/or lower sensor noise. To demonstrate it, sample images at small size are nice but may be merely "andecdotal". We need a rigorous apples-to-apples comparison: the identical stationary scene, shot on a tripod, using the same lens at the same f/stop and shutter speed, where the only difference is that one camera has been converted and the other one (the same model) has not.
Perhaps I am mistaken but as with other factors like vibration reduction, the difference may boil down to some factor (like degree of enlargement, higher ISO or deeper underexposure) beyond which the difference becomes perceptible.
Perhaps the difference is only evident at 100% size. Perhaps a converted sensor allows you to print twice as large as you could before, or you get 2 extra stops of usable dynamic range... Whatever it is, I'd love to see the metrics and compelling side-by-side comparisons... in black and white
I asked Daniel from Monochrome Imaging Services about this a while back: I look forward to seeing them....Show more →
I hope I’m being pessimistic here... but thinking about his samples, other than the one sharpness page with the car, which is noticeable but not extreme... there isn’t much. Someone else has asked for these samples before, and now your request is taking a while... surely he has cameras and a lens, samples should be easy to come by, but there seems to be resistance to posting 1:1 comparisons. Based on what you found with the one RAW, it may well be that aside from sensitivity it isn’t as severe a benefit as we hope it will be... I’ll be happy to be wrong here.
rdeloe wrote:
I'm totally with you on the need for controlled, side-by-side comparison. A few posts earlier in this thread you'll see I promised to post some links to RAW files that will allow us to do that (courtesy of Daniel from Monochrome Imaging Services). Looks like you did too. They're not up yet on Daniel's site, but stay tuned.
Mathieu18 wrote:
I hope I’m being pessimistic here... but thinking about his samples, other than the one sharpness page with the car, which is noticeable but not extreme... there isn’t much. Someone else has asked for these samples before, and now your request is taking a while... surely he has cameras and a lens, samples should be easy to come by, but there seems to be resistance to posting 1:1 comparisons. Based on what you found with the one RAW, it may well be that aside from sensitivity it isn’t as severe a benefit as we hope it will be... I’ll be happy to be wrong here.
This is really interesting... I downloaded the two sample files, converted the monochrome file to DNG using the Monochrome2DNG application. Then I brought the colour ARW and converted DNG into Lightroom 7.3 and converted the colour ARW to black and white using the Adobe Monochrome profile. I adjusted exposure and highlights for the two files to get them roughly the same. Then I compared...
My first thought was that the point of focus was in a different place in the ARW image because it looked fuzzy in comparison to the monochrome DNG. I checked Daniel's site and he says the lens is focused the same for both images. Scanning the two images seems to confirm that; the ARW version seems to me to be less sharp everywhere (which I mistook for a focus issue).
Based on this sample, the difference is just ridiculous... as in the monochrome DNG is simply sharper everywhere. It's hard to compare tonality because of the different exposures, but it looks like the DNG version is a bit less contrasty and did better in shadows.
I'm the type of person that needs to see more carefully made side-by-side pairs before I get too excited. But the apparent resolution gain I can see in this one pair is simply astonishing.
See for yourself.
By the way, I'm a Fuji shooter, but apparently converting a Fuji camera to monochrome is do-able too...
AZSteve wrote:
Hey, Scho, thanks for the internal filter tip, worth the forum price of admission already. Vignetting? Effect on hot spots?
As to hot spots, I was vaguely supposing reflection off the sensor/internal filter was at least partially involved, and the Kolari site seems to provide some support for that idea, although there must be more going on.
Boy, some of these filters are expensive!
I haven't seen any hot spots using the Astronomic CC in my a7R(m) with any of the lenses I've used. There will be some vignetting if you use a shift lens. I experienced this on my Actus when using rise/fall for framing. Otherwise no problems with standard e mount lenses.
Aren't these the same files which have been available before ? If I recall correctly, Daniel has already been providing these images, on request, for some time.
No clue. Perhaps these are ones he's provided by email request, because it said somewhere on the site that he'd do that if you ask. I didn't have them before, and now I do because he put up links so you don't have to request them anymore.
I'd certainly like to see lots more side-by-side comparisons. As I said above, I'm excited by what I saw in this comparison... but I wouldn't consider going this route without seeing a lot more side-by-side samples so that I could be sure that the cost (money for conversion, having to lug around filters, losing the ability to adjust tone via colour channels) was worth the benefits.
Kenneth Lee wrote:
Aren't these the same files which have been available before ? If I recall correctly, Daniel has already been providing these images, on request, for some time.
I think what you guys are seeing are what Foveon users have been seeing for a while: when you don't have to demosaic, you get lots of more resolution from the sensor. The two sample files from Monochrome Imaging remind me of that effect when I compare them (mono run through monochrome2dng, and both loaded into the latest Lightroom Classic CC with Adobe Monochrome profile, and auto B&W mix).
