Page 1 of 1

Suitable lens for scenario

PostPosted: Tue Jan 09, 2018 4:53 pm
by Gaz Sims
Hi folks

I am looking to install some Blackmagic equipment in a venue.

Looking at the possibility of a BMD Studio Camera and adding the best lens for the requirement, but the lens part is causing me headaches!

What lens would you recommend if I want to get a nice tight head and shoulders shot of a speaker who is on stage 17m away but also flexible enough to get some good close ups towards the back of the stage which is 22m. Ideally as well it would be able to zoom to a less close up shot too.

Not sure if i’m making any sense, but just a bit confused because i’m Ok with the technical knowledge but completely lost when it comes to lenses!

Thanks in advance

Re: Suitable lens for scenario

PostPosted: Tue Jan 09, 2018 10:17 pm
by Baz

Re: Suitable lens for scenario

PostPosted: Wed Jan 10, 2018 11:28 am
by Xtreemtec
Baz your video link seems hidden. As it points to my own profile backend were i have my hidden video streams and videos.. ;)

Re: Suitable lens for scenario

PostPosted: Wed Jan 10, 2018 11:47 pm
by Baz
interesting...
Hmmmm.... try this then:

Re: Suitable lens for scenario

PostPosted: Sun Jan 14, 2018 8:51 am
by Gaz Sims
Hi Baz.

What tripod and lens are you using there? I like the control you have over the lens from the arm of the tripod.

Gaz

Re: Suitable lens for scenario

PostPosted: Sun Jan 14, 2018 4:01 pm
by Andrew Martin
Daniel, just as an FYI baz's link opens just fine here.. unless of course he's been back to edit the entry? Links to the same video shown in his 2nd post.

:-) A.

Re: Suitable lens for scenario

PostPosted: Sun Jan 14, 2018 4:46 pm
by Xtreemtec
Andrew Martin wrote:Daniel, just as an FYI baz's link opens just fine here.. unless of course he's been back to edit the entry? Links to the same video shown in his 2nd post.

:-) A.

The link trows me to >> https://www.youtube.com/my_videos?o=U Hence probabbly the "edit?o=U&video_id=" in the link..

I have a Google and youtube account logged on all the time..
The video he placed now was without the "edit?o=U&video_id=" and it works now.

Re: Suitable lens for scenario

PostPosted: Mon Jan 15, 2018 1:22 pm
by Gaz Sims
Hi all

Will this lens get me good close up head and shoulders shots at a 17-20 meter distance and is it compatible with the BMD Studio Camera 4K without adaptors?

Lumix H- rs100400e

It seems from my research to be a good option but not sure if I’m missing something obvious!

Thanks

Re: Suitable lens for scenario

PostPosted: Mon Jan 15, 2018 6:23 pm
by Denny Smith
A 200mm lens will give yiu a nice head and shoulder shot at 17meters (50-feet), somthe 100-400 Zoom should work, but it is a very slow lens at f/4-6.3. So at 200mm the max f/stop is going to be around f/5.6.

This long Zoom was really designed for outdoor nature shooting. Also yiu are going to need a real solid platform for the camera for any lens longer than 100mm, and a solid floor under it. Any movement for vibration to the camera is going to cause image movement and jitters. I would try to get the camera closer to the speaker, and use a 20-60 Panny Leica Zoom, which is what I use on the Micro Studio Camera.

The Micro Studio allows camera placement much closer, add a remote pan/tilt head under it send yiu can hide the camera a edge of stage, and run it remotely from the ATEM/recorder location.
Cheers

Re: Suitable lens for scenario

PostPosted: Wed Jan 17, 2018 5:37 pm
by Gaz Sims
Thanks for the reply.

I understand that regarding the lens and the crazy long zoom distance. Unfortunately we’ve looked at any other options and just can’t get any closer. In practical terms, how will that f-stop affect my shots?

The shake is definitely a consideration, but I think we’ll be OK as it’s going on concrete! Hopefully no stampedes will go by, but we might have to watch out for the bassline! :)

If there are any other suggestions for a lens over that distance that will be compatible I’d love to hear them!

Thanks again

Re: Suitable lens for scenario

PostPosted: Wed Jan 17, 2018 5:51 pm
by Denny Smith
The BM Studio camera’s are not low light cameras, so a f/5.6 is going to need twice as much light in the subject than at f/4.5. Shooting stage type lighting, I used to be at +6 dB Gain at f/2.8-3.5, so f/5.6 is going to result in underexposed, noisy dark looking image. You need to meter your set location using iso 400 (which is about +6db Gain in Stuido Camera) and see how much light you will have. Also, the further away the camera, the more light is needed to reach the camera location.

ENG cameras that were normally used for this type if shooting, had lenses at f/1.4 to 2.0, to open up to get more light on the sensor. Unless you have a well controlled situation with lots of light, as in a TV studio, a f/4.5-5.6 lens is not going to work with a BM studio camera.
Cheers

Re: Suitable lens for scenario

PostPosted: Wed Jan 17, 2018 9:14 pm
by Howard Roll
Gaz,

Look into the pCam it's got a lot of great tools for answering questions exactly like these.

17m.jpg


22m.jpg


You can see you're looking at about 270-370mm. That doesn't leave you a lot of options for anything moderately fast.

For example a f5.6 at 0db gain which is the mid setting under the latest firmware you need 1060 lux or about 100 foot-candles to expose mid grey at 40 IRE with 1/60th shutter at 29.97. For a more broadcast friendly 50 IRE you need 1660 lux or about 155 foot-candles.

To add to what was said earlier don't underestimate the effect that shooting at such long focal lengths will have when operating. I've got a Sachtler FSB6 and any interference more substantial than a gentle breeze becomes noticeable above 150mm. It's definitely worth considering decaf.

Good Luck