The Canon XL1 was (and still is) a pretty decent pro-grade rig. Large lens diameter (72mm with the included lens - varied as the XL1 has an interchangeable lens system) and large (1/3 inch) 3CCD imaging chip system... and recorded low compression, high quality, standard definition, video to miniDV tape. It is very easy to capture better looking video with this rig than an inexpensive consumer-grade camcorder. As well, manual audio gain control + a host of useful and commonly used manual controls on the outside of the camcorder (not buried in a menu. Some would have considered this a pro-grade rig - the only thing missing is XLR audio inputs for external mics.
Here is where I need some clarification on your list:
1) You want "professional looking" without professional gear. Fair enough - assuming it is the person behind the camera as opposed to the camera itself... SPend less on the camcorder and likely spend more on lighting. Is there a separate budget for lighting?
2) A separate headphone out is not normally on any low-end consumer cam... maybe midrange or higher, but low price is all about cutting features to save money - you can use the audio portion of the AV-out for audio monitoring, but there is no level control. If a separate, level controllable headset out is required, then you'll probably need to increase your budget. Is volume control on the headphone-out for audio monitoring required? Audio inputs are one thing - but the ability to manually control the audio gain is another. Is manual audio gain control required?
3) Replaceable memory without removing the camcorder from the tripod - fair enough. No clarification needed here.
4) There is no "unitversal shoe" fro tripods. Each manufacturer has decided to make their own. The 1/4 x 20 screws are universal, but the quick release plates are manufacturer specific. Many manufacturers make different quick release plates, too - so a QR plate from one tripod may not work with another from the same tripod manufacturer. This is not a camcorder manufacturer issue...
5) Capture sill and built-in memory (in addition to removable memory... but a "want" not a "need".
6) You did not tell us which Mac, what version OSX or which version Adobe Premiere. We'll need to know that to understand what the editing process flow might be.
7) OK. No clarification needed other than that which was requested in item 6. We assume the Mac has adequate RAM (4 gig; but 8 gig is better) and a CPU from the last year or so... and LOTS of external hard disc drive space...
Your price range has us at the entry level Canon Legria HF R area. Similarly priced competitors from Sony and Panasonic will trade various capabilities. I think the Canon Legria HF M506 gets the volume-controlled headphone monitoring, but you should check the manual from Canon UK yourself. You may need to either reduce your expectations/requirements or increase your budget... I hope this Q/A helps...
I haven't owned a camcorder since my XL1 packed in about 7 years ago and am in need of a decent but fairly cheap camcorder to film professional looking webinars and online sales videos.
I have a checklist of needs and when I do a general search there always seems to one of the requirements missing.
1. Image quality (yes its relevant to price but it needs to be of a professional looking standard)
2. Microphone / headphone out socket. I may be doing interviews which need to be of best possible quality so this is a necessity really as will be using radio mice from time to time.
3. Good memory and sd card slot accessible without taking off a tripod.
4. I own a tripod already so a universal shoe would be preferable.
5. Also on my checklist but not necessary is good still image quality and in built memory.
6. Not sure if its necessary anymore but run an iMac with Adobe Premiere so mpeg-4 recording format and AVCHD was what I needed to look out for previously. I think most are compatible now though.
7. Wi-Fi is not needed as I will be importing all footage into Premiere for post-production.
Budget is between £300-400 but will go higher if the right camera is out there.
Thanks for any help.

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