I'm still dithering as to whether the upgrade to the C300 Mk2 is worth the outlay.

I'm really keen to get my hands on the new C300 Mk2 autofocus features but apart from that I'm still pretty happy with my C300.

I'd be really interested in general feedback as to whether the image quality and other improvements have been worthwhile.

The other options are clearly the Sony FS7 or FS5 both of which are considerably less expensive than the C300 Mk2.

Barry did a nice write up yesterday in another thread - http://www.dvinfo.net/forum/canon-cinema-eos-camera-systems/530715-c300-mark-ii-matrix-skintones.html#post1906835 .

Thank's Jon - saw the original post but not subsequent messages.

Guess I need to hire one for a day.

Really liked it when I saw a pre release model.

One unfortunate thing is that I'm pretty sure there is still no way of directly importing the new files into FCPX.

Mark - my understanding is that the 444 cannot currently get into FCPX but the 10-bit 422 can. Barry's got more info in the comments thread with his video from that other thread, over at Vimeo: C300 Mark II Color Matrix Skintones on Vimeo

Not sure how to link to the comments directly but you see them at Vimeo.

"All the 10bit codecs work fine with FCP X (fcp transcodes them to whatever you have set for 'optimized')."

I'd be really interested in general feedback as to whether the image quality and other improvements have been worthwhile.



Hi Mark,

I really haven't had time to do A/B testing with the C300 and the Mark II, but I'll give you this. Having come from the land of the XL1/XL2/XLH1 followed by the 5d mark II, the C300 attracted me first at Canon's Paramount Launch --seeing footage shot to a CF card projected beautifully on a 90 foot screen was eye opening for me and I plunked my money down on that camera right away.

Over the years of using the C300, I too was quite happy with it. Most of the time. Often it was a struggle shooting daylit interiors. Overcranking at 720p was frustrating. Occasionally the colors didn't really seem as pure as I'd like. Skintones were largely good, as long as you didn't overexpose them, but with Canon Log's shadow weighted curve, tendency to saturate on the highlight end, and 8 bit color depth, it often took more lighting than I'd prefer (or frankly, preferred to carry), to keep those skintones in the zone they needed to be in to look great every time. I kept hearing that shooting with an Alexa made it so much easier to get nice skintones in situations like this, and I knew that I wanted a camera that could do that...(although I certainly wouldn't be getting an Alexa.)

My first shoot with the Mark II featured a motley crew of children, singing a holiday song. I lit the scene with the same tools I often use. 2 Area48 LED through a 4x4 with Lee 250 diffusion. I shot in original canon Log. I can tell you the skintones were simply a different animal than anything I'd ever seen with the C300. They were more delicate and colorful...The color seemed much less baked in to me. The highlights didn't seem to be on the edge of oversaturation. This was a different camera. (To say the skintones were Alexa-like, well having never shot with one, I'm unqualified...but they look a lot like what I think Alexa skintones look like.)

Since then I've used the camera on a number of smaller shoots. Mostly, my first impressions haven't changed...this is a very new camera in terms of the tools it offers and in terms of the way in handles color.

Although I haven't taken advantage of it much yet, having the ability to utilize the full range of the sensor in CLog2 has very little downside. Apply canon's luts and it simply looks beautiful. The much storied "noise" in CLog is really something you only see when you don't know how to expose a cineon type log curve. When exposed properly, it looks great. The only weak areas of CLog2 that I see, are working in Low Light, and when trying to use face detection. Both situations are more appropriate to the original Canon Log.

The internal codec on the Mark II is really solid. I don't see a need for a recorder with this camera, ever. The on board monitoring allows you to get a very good appraisal of what the footage looks like (something you would never say about the original c300), and I have no problems using the EVF for critical focus in HD. I am looking at a smallHD 702 for external monitoring, but only because my 52 year old eyes are going.

While I really don't see a need for 4k in my work, I have played with it. It makes me want to use it all the time. It's a very pretty 4k image.

I wish it wasn't so heavy. I like all the new connection points on the handle, but I actually think I prefer the lighter weight original handle. So it squeaked a little...big deal.

On other thing I've noticed Canon has cut the rolling shutter frequency by half. It's noticeable when handholding. Feels more and more like a film/global shutter to me. That's a big change. The original was no slouch, but this is definitely improved.

That's it for now.

Hi Barry,

Really great response - thanks.

My shooting style is almost 100% documentary. I work with a producer / interviewer and handle all the technical aspects of the shoot myself.

Interviews form the backbone of all our work. The reassurance offered by the advanced autofocus would be a huge benefit for me and take a lot of the stress out of the job.

I'm still dithering as to whether the upgrade to the C300 Mk2 is worth the outlay.

I'm really keen to get my hands on the new C300 Mk2 autofocus features but apart from that I'm still pretty happy with my C300.

I'd be really interested in general feedback as to whether the image quality and other improvements have been worthwhile.

The other options are clearly the Sony FS7 or FS5 both of which are considerably less expensive than the C300 Mk2.

I could have happily carried on using my C300 mk1 for another year or two but I wanted the updated autofocus, especially the face assist and the 4K.

Biggest issue for me so far is that you can only extrenally record 4k in RAW format which meant I had to spend more £££ upgrading my Odyssey 7Q+.

Haven't had a chance to use it much as I'm still waiting to pick up batteries and Cfast cards. Boy.... are they expensive!!!

By the way, be aware that prices on some UK dealer websites are about £2,000 more than what they sell for when you walk in and make a deal face to face. I picked up mine for £9,300 plus vat just after Christmas.

On top of which you could get between £1,700 and £2,500 trade in against your C300 mk1.

I used both my cameras on a shoot today. I have to say, the Mark ii is just a better camera. Canon has figured out a bunch of the small, annoying things the C300 (original) got wrong.

The biggest change for me is the LCD viewfinder, which on the mark ii is just leaps above the original C300 LCD. No contest. I also use a Gratical HD, I found the LCD was easier to gauge critical focus on than the Gratical.

One hiccup is that the magnification is not functional while recording... that needs a firmware update pronto! I rely on that all the time with the original C300... and very much while using my Canon Cine lens.

Overall, I see the Mark II as a replacement for the original C300 as my primary camera. The original C300 is now a B-camera and the 5Dm3 is not going to get the heavy use it once has. I will probably use the mark ii in 1080p about 90% of the time this year.... I don't have a lot of 4k requests.

For me, it comes down to the luxury of using a tool that I wanted, but didn't necessarily need. It makes my life easier, so I went for it and I think that peace of mind is worth the jump in cost over the next year or two.

Get the Zacuto kit if you shoot doc style or on the shoulder. It makes the camera into a real ergonomic wonder, especially with the 17-120mm lens mounted. It is heavy in that configuration... but so were my HDX900 and Betacams. Don't get the Arri or Shape rigs... they are way overbuilt for everyday ENG type work and they are not as nicely designed. The Zacuto rig isn't perfect but it is pretty darn good.

To compare to another camera... my opinion as a working DP, is that the FS7 is a toy compared to the C300 Mark II. I just used an FS7 last week and I was surprised by how cheap and cheesy it felt in my hands. It does make a nice picture, and it is cheap to buy, but it doesn't inspire confidence... kinda like using an EX3. It is a cheap tool. The Canon, on the other hand, feels ergonomic and well laid out. It is easy to navigate and it doesn't have the damn Sony menus that I have grown to hate. That's my gut feeling on comparing the FS7 and the C300mII.

Mark,
I have been shooting with a C300 since 2012. The C300 Mark II removes most of the pain points from the original C300. The 4K files are lovely. The low light ability is better so you can push up the ISO.

The autofocus is nice and you can use the focus point around the screen. If you are using cinema lenses for your interviews, there is also an on screen indication of which way you need to rotate to get the focus. When critical focus is obtained it becomes green. I am not missing the image magnification during recording as I found the focus aids working well. Nevertheless I am sure Canon will bring the image magnification during recording with a firmware update. Here is the link to my short review. Hope it helps: https://youtu.be/dUVBOjMP_VM

Hi Sabyasachi,

thanks for that reply and thoughtful video review (watch out Philip Bloom!)

I've no doubt that the MK 2 is a brilliant camera from the images I've seen.

If I do make the new investment it will be mainly for the advanced autofocus. I'm of an age where reading glasses are a necessity and sometimes I simply don't pin down the focus and the thought of working with a shallow depth of field in a dynamic documentary situation is pretty alluring.

As to future MK 2 firmware updates. My experience going back to the launch of the C300 is that Canon respond to firmware updates in a very oblique manner and that whilst they might improve operational aspects of the camera you need to be happy with what you are buying at point of sale.

Apart from restoring the very basic ability to punch in to the image on the monitor or viewfinder whilst recording my other desired improvement would be that they provide the ability to record 4K at a far lower bit rate - say 100mbs.

Oh yes, and an affordable small servo zoom lens. Sony manage it so why not Canon?

Apart from restoring the very basic ability to punch in to the image on the monitor or viewfinder whilst recording my other desired improvement would be that they provide the ability to record 4K at a far lower bit rate - say 100mbs.

No way. This is a professional cinema camera, they are not going to include the ability to record consumer-level 4K. If you want consumer 4K, plenty of options for you.

If you cannot handle the bitrate of professionally captured 4K, then you need to stay away from 4K.

Period.

"If you cannot handle the bitrate of professionally captured 4K, then you need to stay away from 4K."

I use 4K already with Sony and other cameras and to say I should stay away from 4K if I can't 'handle' the bitrate of professionally captured 4K is a tiny bit restrictive.

There are lots of uses for these cameras from broadcast through to commercial applications. 400Mbs is very taxing on recording media and the trickle down of backup etc.

The Sony FS7 which is considered a Broadcast camera offers bitrates from 600Mbs down to 250Mbs.

The Canon C300Mk2 seems to offer Just 410Mbs ?

The Sony FS7 which is considered a Broadcast camera offers bitrates from 600Mbs down to 250Mbs.

None of which are your 100Mbps request. Which is consumer.

Plus, that's not entirely accurate, as those bitrates are dependent on frame rate.

The Canon C300Mk2 seems to offer Just 410Mbs ?

Yes, and it's twice as much as the FS7, which means better quality because the 600Mbps is for 60p, which the C300 doesn't have. The 24p bitrate of 4K is 240Mbps.

4K is 4 times the resolution/data of 1080. If you can't handle 4x the size, then you shouldn't be dealing with 4K. At least 410Mbps is a lot better than the 800Mbps of ProResHQ in 4K.

Regardless of whether 100 Mbps is consumer or not, for some projects it could be nice to have a lower data rate option in situations where the client requests 4K, but schedule pressure requires fast transfer times with little processing and where coding quality is secondary. Otherwise, one needs to carry a second, cheaper camera which wouldn't just have lower data rates, but also lower DR, low light capabilities, and a lack of other pro features. The C300 mkII look, even at 4K - 100 Mbps, isn't achievable with consumer cams.

4K is 4 times the resolution/data of 1080. If you can't handle 4x the size, then you shouldn't be dealing with 4K. At least 410Mbps is a lot better than the 800Mbps of ProResHQ in 4K.

Gary - you seem to assume that the only people who will use the C300 Mk2 with is high 4k bitrate, will be or should be, broadcasters.

By Launching the cameras in Hollywood Canon clearly positioned their C Class cameras at top end production work. But the C300 has been a huge success in many areas of the industry, cinema, broadcast documentary, advertising and industrial television.

The C300 Mk2 is a slightly different proposition in that it shoehorns the C300 and C500 together to create the new camera. And very nice it is too!

But in someways Canon seem to want to maintain an elitist marketing and product development model whereby they presume to differentiate their products from the rest of the market place. The result is that many C300 owners have now moved over to the far better value Sony propositions such as the FS7 and the new FS5.

Sony have actively and very publicly courted the views of top technicians and camera operators and created a new range of very powerful and versatile cameras. They also respond very quickly to feedback over issues with their equipment and rush out firmware updates. They really seem to care about what people are saying about them and their products.

Canon meanwhile seems to sit in an Ivory tower clearly separated from direct communication with it's customers. Just a few minutes looking through the archives of this specific forum will remind us of the huge fight to get even minor improvements implemented with the C300.

So a request to have a few more bitrate options when recording 4K with the C300 Mk 2, and to have the ability to punch into the image to check focus whilst recording is not unreasonable.

Hi Sabyasachi,

thanks for that reply and thoughtful video review (watch out Philip Bloom!)

I've no doubt that the MK 2 is a brilliant camera from the images I've seen.

If I do make the new investment it will be mainly for the advanced autofocus. I'm of an age where reading glasses are a necessity and sometimes I simply don't pin down the focus and the thought of working with a shallow depth of field in a dynamic documentary situation is pretty alluring.

As to future MK 2 firmware updates. My experience going back to the launch of the C300 is that Canon respond to firmware updates in a very oblique manner and that whilst they might improve operational aspects of the camera you need to be happy with what you are buying at point of sale.

Apart from restoring the very basic ability to punch in to the image on the monitor or viewfinder whilst recording my other desired improvement would be that they provide the ability to record 4K at a far lower bit rate - say 100mbs.

Oh yes, and an affordable small servo zoom lens. Sony manage it so why not Canon?

Flattered by that comparison with a hugely talented and flamboyant shooter/presenter like Philip Bloom.

I understand the need for a "lite" version of 4K. However, I don't think the low bit rate at say 100Mbps would be great. If you check the Full HD 50p footage it is fine but obviously the 4K has more details. However, since one can live with Go Pro 4 footage (I have been using it in aerials), then certainly we can also live with a lower bit rate footage for certain applications. It doesn't hurt to give it via a firmware if there is enough demand from users.

As far as servo zoom lens is concerned, the 17-120mm servo lens at 31K USD is not affordable for many productions. I think you should also try the constant aperture still lenses like EF 70-200 f2.8 L II USM and do the zoom in or zoom out. I have tried that with the C300 Mark I. If the subject is at the centre (for C300 Mark I) the focus holds on and it works. In C300 Mark II with better and face detect AF working on 80% of the area, you should be able to get away with using a still lens like EF 70-200 II. I will try this later with the Mark II.

Gary - you seem to assume that the only people who will use the C300 Mk2 with is high 4k bitrate, will be or should be, broadcasters.

Not at all, I assume there are people who buy too much camera for the work they do. They absolutely exist. I also have a C300 Mark II and I do not consider myself a broadcaster, although my work has been broadcast live.

But the C300 has been a huge success in many areas of the industry, cinema, broadcast documentary, advertising and industrial television.

Not sure why you're sounding like the brochure here, but that in no way displays a significant user base who would demand a consumer level 4K codec.

The result is that many C300 owners have now moved over to the far better value Sony propositions such as the FS7 and the new FS5.

And yet the C300 Mark II is selling very well despite that. In fact, I heard just yesterday of an individual who purchased an FS5 and then returned it after use for the C300 Mark II, despite the price differences.

Sony have actively and very publicly courted the views of top technicians and camera operators and created a new range of very powerful and versatile cameras. They also respond very quickly to feedback over issues with their equipment and rush out firmware updates.

Rushed out firmware just like 3.0 for the FS7, eh?

So a request to have a few more bitrate options when recording 4K with the C300 Mk 2, and to have the ability to punch into the image to check focus whilst recording is not unreasonable.

The second is not, I am championing that myself. The first is. Again, if you need a consumer codec with 4K, then you shouldn't bother with 4K, or check out the myriad of other choices that shoot consumer-y 4K...like the FS5. People are so enthralled with the 4K option in that one, let me tell you.

Gary - not quite sure where this one is going.

And I really don't want to get into a silly argument with you!

Your welcome to your viewpoint and I really haven't got anymore to add on this 4K bitrate ping pong match.

Compared to other forums this one tends to be pretty measured and respectful and lets keep it that way.

Compared to other forums this one tends to be pretty measured and respectful and lets keep it that way.

There was no disrespect, unless you inability to retort back suddenly means you're being disrespected.

The C300 Mark II getting a 100Mbps 4K codec is equally as plausible as the PMW-F5 getting it, because the C300 Mark II is priced in competition with that cam, not the FS5.

But in someways Canon seem to want to maintain an elitist marketing and product development model whereby they presume to differentiate their products from the rest of the market place. The result is that many C300 owners have now moved over to the far better value Sony propositions such as the FS7 and the new FS5.


My guess, Mark, is that whatever form the C100 takes in it's next iteration, it will be with a 4k codec like you describe. The C300 is the top beast now, but that shouldn't suggest that canon doesn't know where the real market is, just look at the number of posts on any forum regarding the c100 versus the c300/500. The C100 is where that codec belongs and will most likely be...although I think it will be somewhere north of 100mbit.

While I see the value in putting it onto this existing camera, I think Canon won't consider it as they've always cut features (like 4k/60p, which this camera should have no problem with) when they felt there would be a quality penalty due to limitations of the codec. Sony having to answer questions about the Fs5 codec now is a pretty strong incentive NOT to put a low grade codec in the C300II.

My guess, Mark, is that whatever form the C100 takes in it's next iteration, it will be with a 4k codec like you describe. The C300 is the top beast now, but that shouldn't suggest that canon doesn't know where the real market is, just look at the number of posts on any forum regarding the c100 versus the c300/500. The C100 is where that codec belongs and will most likely be...although I think it will be somewhere north of 100mbit.

While I see the value in putting it onto this existing camera, I think Canon won't consider it as they've always cut features (like 4k/60p, which this camera should have no problem with) when they felt there would be a quality penalty due to limitations of the codec. Sony having to answer questions about the Fs5 codec now is a pretty strong incentive NOT to put a low grade codec in the C300II.

Good points Barry.

Should the C100 be upgraded again I would think it would have the same 4K codec as the C300 Mk2. The XC10, which I owned for a short while, provided 4K Recording at 305Mbps/205Mbps at 25.00P. Thats using the same XF-AVC video format. (MPEG-4 AVC/H.264)

That camera is let down by a plastic fantastic viewfinder and mediocre lens. I feel they would have done well to have provided better components and charged a higher price.

From what I've read the problems with the FS5 codec seem to occur when users are pushing the camera in low light situations. Sony is responding to these concerns.

The XC10, which I owned for a short while, provided 4K Recording at 305Mbps/205Mbps at 25.00P. Thats using the same XF-AVC video format. (MPEG-4 AVC/H.264)

It's also 8-bit and not 10-bit, hence the lower bitrate.

To compare to another camera... my opinion as a working DP, is that the FS7 is a toy compared to the C300 Mark II. I just used an FS7 last week and I was surprised by how cheap and cheesy it felt in my hands. It does make a nice picture, and it is cheap to buy, but it doesn't inspire confidence... kinda like using an EX3. It is a cheap tool. The Canon, on the other hand, feels ergonomic and well laid out. It is easy to navigate and it doesn't have the damn Sony menus that I have grown to hate. That's my gut feeling on comparing the FS7 and the C300mII.

That's similar to my experience Scott. I've owned a C300 since it was released and it's been a superb tool for me. Just a really solid, reliable workhorse that delivers very predictable images.

I briefly owned an FS7 (lured by the price / spec combination) and found it a constant battle to work with. Despite the ergonomics being a selling point, I found it flimsy and hard to balance without a full rig. The menu system is painful. And in post, good skin tones were just so much harder to achieve than with the Canons. All in all, while it's a great camera on paper and the price is attractive, I just found myself fighting with the camera rather than being able to concentrate on the shot.

In the end I had to suck it up and sell the FS7 at a loss and pick the C300mk2 when it came out. Barring a few nuisance issues (lens and monitor compatibility, focus magnification), the camera is a joy to use, the images are great, and it's very simple to achieve great skin tones. The build, LCD & VF as well as the focussing system are all superior. All the little things just add up to being a vastly more intuitive camera to use. It's definitely worth the price premium over the Sony.

I received my Mk 2 last week.

Initial impressions are of a far more robust and professional unit. I've yet to carry out any field tests and will probably start recording at a pretty basic level whilst I get used to it. That means pretty much matching the settings I use on my C300.

Still some deeply annoying design shortcomings such as having to use a hex spanner to to take the handle off, the inability to move the WMF display position about or off the screen and the lack of magnification whilst recording.

I've ordered the Zacuto Graphical HD viewfinder and intend to use their scopes and magnification whilst recording.

Probably the only information I'll need displayed over the image will be the focusing aids.

But overal I'm really delighted with the camera and the only problem I have now is the decision of whether to keep my C300 or sell it at a silly price.

Congratulations Mark. It is a big step up from the C300 in most areas.

Completely agree on top handle (it's much improved but needing a hex key is a pain for transport), focus mag and WFM position. Hopefully the latter two can be fixed soon via firmware.

The little thing that's bugging me is the extra two channels of sound being force recorded to channel 3/4. That is, if you record to either or both inputs 1/2 via XLR, channels 3/4 record junk audio from the tiny built in mic. I understand this might be useful for two system audio slate (although even that's hard to figure if you have two XLRs in use), but generally it's a nuisance.

There doesn't appear to be any way to disable it in camera: you must remember to manually remove it in post and tell others to do so if you're handing the footage over.

understand this might be useful for two system audio slate (although even that's hard to figure if you have two XLRs in use), but generally it's a nuisance.

The problem with being able to disable the extra two channels is that, by the time you realize you might need it, it'll be two late.

Is it really that hard to disable it or to pass it down the line? At some point if some third-party editor cannot figure it out, perhaps they should not be paid to be editing? It's no different than disabling your safety second channel set at a slightly lower input volume than your first channel.

The problem with being able to disable the extra two channels is that, by the time you realize you might need it, it'll be two late.

Is it really that hard to disable it....

I don't have a use for the audio recorded to channels 3/4 by the pin prick mic. It's not "hard" to disable in post, but as a FCPX user (which does not have a traditional timeline) it's certainly a nuisance. It adds an unnecessary step every time you add a clip to a project as the audio properties have to be changed within individual clips.

It would simply be nice to be able to control the volume of these channels, as you can for 1/2 (or indeed for 3/4 if you plug a stereo mic in via 3.5mm jack).

I agree it would be nice to have some additional control over channels 3/4 in the Mark II, but I am happy that a scratch track is there. It certainly was missing in the original C300, which became problematic anytime you needed to use pluraleyes and didn't have a mic connected.

It is also nice to have scratch camera mic just to always have some ambient recording for post to access. They probably won't need it, and usually I have soundie sending or recording clean audio anyways, but when you break away from soundies and suddenly you have no mic attached for broll... the camera's scratch solves the problem.

Post will understand instantly that the 3/4 audio from the camera is just scratch. It will not sound great, but provides something for Pluraleyes to sync to and provides at least a sound bed for broll.

I am confused, though, why it isn't more configurable... would be great to have access to those channels to record outside sources. Why send scratch to two channels, anyway? It just needs to be on one of them. I'm sensing a firmware update by Canon that would address channels 3/4 (at least I am hoping Canon will do so!).

Post will understand instantly that the 3/4 audio from the camera is just scratch. It will not sound great, but provides something for Pluraleyes to sync to and provides at least a sound bed for broll.

I use it specifically for this purpose with two cameras, even though I have a Shogun which will do LTC in. There's a bug where it won't do it for 24p when 24p has 3:2 pulldown applied to it (i.e. C100 Mark II with a Shogun and the C300 Mark II as the primary). Thus, for 24p projects, I have to use the scratch track to sync.

configurable... would be great to have access to those channels to record outside sources.

If you plug a source into the 3.5mm jack doesn't that record to 3/4?

I will have to test the mini plug input... which I will admit... I didn't even pay attention to on the camera. I guess I need more time with my own camera!

If it does take external input to channels 3/4, then it would still be great to be able to adjust those channels and have some configurability. I can imagine using a stereo mic to channels 1/2, an IFB source from mixer on channel 3 and the camera's mic on channel 4. Or, perhaps using a tentacle (tentacle sync (http://tentaclesync.com/)) on channel 3 along with camera mic on 4, etc.

More options, more better!

I don't have a use for the audio recorded to channels 3/4 by the pin prick mic. It's not "hard" to disable in post, but as a FCPX user (which does not have a traditional timeline) it's certainly a nuisance. It adds an unnecessary step every time you add a clip to a project as the audio properties have to be changed within individual clips.

It would simply be nice to be able to control the volume of these channels, as you can for 1/2 (or indeed for 3/4 if you plug a stereo mic in via 3.5mm jack).

Not sure if you've already tried this, but in FCPX you can select as many clips in the clip browser as you want, and then go into the Audio Inspector and uncheck/disable scratch channels. That makes it so you won't have to remember to disable the scratch audio every time you place a clip in the project/timeline.

I usually record a scratch track during B-roll as well as interviews, so this FCPX feature allows me to disable that scratch before I begin editing. But the scratch tracks are still there if you ever need them. Not sure how C300 clips import, but C100 clips usually imports as stereo tracks, so I select all clips and convert them to dual mono and then disable the scratch track.

Hope that saves you some time, cheers -
Slavik

Thanks Slavik,

Yep, that sounds right.

If it does take external input to channels 3/4, then it would still be great to be able to adjust those channels and have some configurability. I can imagine using a stereo mic to channels 1/2, an IFB source from mixer on channel 3 and the camera's mic on channel 4.

Yes Scott, the 3.5mm input is sent to channels 3/4 (even if the source is mono, it will go to both channels). You can adjust the volume level using the joystick, and you can even apply attenuation. And you can monitor it by configuring the audio outputs.

It makes for some useful options with an external mixer.

However, if you use the 3.5mm input the camera's inbuilt mic is disabled, so you can't quite use it as per your example.