You could take an image with a disc camera, the 110 would be better quality. The 35mm would visually be of a better quality, 120mm however would eclipse it, you would see another marked improvement using 5x4 but in comparison the 10 x 8 is superior.
Confidence comes from knowing your camera, and it's abilities, fully understanding the ISO, Aperture and speed ratios and knowing when and how to apply this knowledge. You could take a photograph with a 10 x 8 Sinar the quality of the image would be sublime. But if you don't understand the exposure ratio or Scheimpflug principle snd know when to apply it you're going to be screwed.
Owning a professional camera does not or should not make you feel any more confident or a better photographer. Yes it can improve the quality of your output (final) image but that's only a tiny part of the story.
Having that knowledge helps but if you've got a good eye for a subject then great images can be taken on an auto point and shoot. It's not the camera but the photographer who takes it. Ten people could look at an image 5 may like it, the other 5 may hate it !
....Yes, I agree about the different qualities of the different camera formats - In my working life I was a professional Art Director and worked (and travelled overseas) with professional photographers with all formats up to 10 x 12, in studios and on location, so I know the differences you describe firsthand.
I also agree about confidence from knowing your camera, car, bike, musical instrument, or indeed any other piece of tactile equipment and that it's only a part of the whole story but I think it's an important part - Cameras are used to express oneself and not just as scientific recorders.
'Having the eye' is just as important as all the technical knowledge - They go hand-in-hand and one helps the other.
And what does my forum signature say and has done ever since I joined TP? :
"The camera takes the photo, but the photographer makes it" - Ansell Adams, 1902-1984
And so back to the title of this thread : It doesn't matter whether you are a professional or amateur, it's always horses-for-courses and you use what you can afford to buy/hire and to the best of your individual ability. Different people feel motivated by different things - There's more than just one way to skin a cat.
Historically back in the days of SLR film cameras, zoom lenses did not have the optical quality that primes did but technology never stands still and that comparison has changed for the better. I assume that most photographers on TP realise that.
I suppose where people get their confidence from is a personal thing.
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@Pookeyhead Phil, this is part of what I have been trying to say to you all along.
