EX1 wide shots advice

[Jamie Roberts]

Hi there,

I am editing a series of clips filmed with the EX1 that include lots of interviews, wide shots using a dolly and a jib, and lots of handheld shots where I keep the camera wide and move in and out as i change framing between wide, close up etc.

They were filmed in various schools (always busy and not a lot of time to get shots) and I always keep peaking on to maintain focus.

The interviews involve a fair bit of depth in the background and I use lighting. Allthough I've done 100's of them i continue to be blown away by the quality. Medium and close shots also look great.

Some of my wide shots however leave something to be desired. A few of them are a little out of focus and they just seem to be average quality particularly when dropped in between interviews, medium/close shots etc.

I'm sure the problem is largely to do with the operator (me) so I'm keen to hear from other EX1 users in regard to whether there is an optimal iris setting for getting nice deep in-focus shots that I can use for a guide in future? Is there anything else i need to consider (perhaps even a Picture Profile that better suits wide shots?). I do intend to draw breath in future and double check my focus and make sure the iris isn't too open.

Any advice appreciated as this is a job for a valued client and although i cant go and redo the dodgy shots, I'm hoping I can learn something from this so I can do better next time.

Thanks

Jamie

[Alister Chapman]

What aperture are you using? More stopped down than f11 and you will suffer from diffraction limiting which will soften your pictures, more open than f4 and lens performance will also soften the picture.

[Luc De Wandel]

I'm not sure if the EX1 has a flange-back adjustment? If so, check if that's OK, because if not, this often causes unsharp images on the wide side of the lens.

[Jamie Roberts]

I suspect Alister that the shots in question were taken wider than F4. I can sometimes get I bit caught up in what I'm filming in these rushed shoots and don't pay enough attention to the iris setting basically trusting the peaking.

I do remember reading something ages ago ( I think in regard to a different camera) about setting aperture that allows for best performance of lens. I shoot at -3db gain and would rather up it to either 0 or even +3db if it means I can keep aperture at an optimum setting and get the best possible wide shots.

Luc I'm not sure about a flange back adjustment. I wonder if this is something I need to get checked. I did ring the service centre a couple of years ago to check if I should get it serviced and was told that unless I'm having particular problems with the cam, there was no need to worry. It has done a lot of work. I might give the uv filter and the lens a good clean in the mean time.

Thanks for feedback

Jamie

[Dave Sperling]

Originally Posted by Luc De Wandel

I'm not sure if the EX1 has a flange-back adjustment? If so, check if that's OK, because if not, this often causes unsharp images on the wide side of the lens.

Sounds like you may want to run the back focus adjustment routine. On the EX1 you'll need to get into the 'hidden service menus' to do that. I know there are other threads about this on DvInfo, so you might want to check there. My EX1 was perfect for about 2 1/2 years, then I started noticing the wide end not quite holding focus. Adjusted back focus and no problems since...

[Alister Chapman]

Sometimes wide shots don't look sharp simply because everything is in focus. When there is no contrast in the shot between in-focus and out-of-focus, sometimes it all ends up looking flat. In addition in a wide shot fine details that might be visible in a close up are not visible.

Back focus is easy to check. Pick a nice textured or detailed object, a brick wall perhaps. Place the camera 5m from the object, zoom in and accurately focus the camera. Zoom out and check that the optimum focus position is the same as for zoomed in. If they are different, then your back focus is out and needs to be reset.

FYI. -3db gain will reduce noise by 3db but also reduces the dynamic range by half a stop.

[Doug Jensen]

In my opinion, the EX1/3 looks just fine with the lens wide open and I would never hesitate to shoot wide open. However, my sweet spot is f/2.8 to f/4.0 and I would never, under any circumstances go below f/5.6. There's a definite drop in image quality beyond that threshold. I have found that keeping the lens consistently a stop or two either way of f/2.8 is not hard at all.

[Jamie Roberts]

Thanks Alister. I will do that test on the weekend.

Thanks Doug and Dave for sharing your knowledge.

Cheers

Jamie

[Jack Zhang]

I personally do use -3db whenever I use a picture profile that requires minimal to no after the fact grading. (IMO, Doug's profile is almost like a real-time grade for my purposes) Only when you shoot with a flat profile (like the BBC ones) would you not want to shoot -3db and opt for 0db.

F1.9 is not recommended on wide for sure. I agree the sweet spot is F2.8 and F4. When I need to shoot low-light, I now find F2.8, 6db, 1080p30 with shutter off (1/30) to be a good compromise with noise and focus/sharpness. F1.9 and 0db on 1080p30 with shutter off still sacrifices too much sharpness compared to lower amounts of noise. YMMV.