4K on Helium Crop?

[AlexJones]

Hi guys so I'm trying to figure something out. I sued to have an Epic MX and used to shoot in 4K a lot for the 120 fps as I shoot wildlife. Now I have a Weapon Helium and have any owners noticed images being soft on the Helium at 4K compared to the MX? I know it crops in much more on the helium so am I seeing more issues with the glass and if thats the case, any workarounds? I upgraded but don't want to lose quality on 4K over my MX. I shoot 120fps a lot.

 

[James Codeglia]

I figure the lenses will show more quality issues in 4K on the Helium vs the MX simply because the crop factor is greater on the Helium. That means lens issues will be more magnified. Then again, you do gain better low light performance (less noise) on the Helium. I can imagine there are different scenarios where each one could be better than the other. Take all this with a grain of salt since I haven't used MX since 2013. Good luck!

 

[Chad Lancaster]

6k 2:1 would get you 75fps according to the calculator.. beyond that I wouldn't go any lower resolution.. you may have to switch to a veo/flex 4k. Not many options in the high speed world.

7.5k on helium would give almost the exact same sensor size as the veo/flex4k

 

[Manfred Baulig]

You can use s16 lenses in 4K. We’re doing that on some projects.

 

[Marcus Friedlander]

I know it's a little late now, but the Helium is really not the best sensor for shooting 4k/120fps because of the crop that you are experiencing.

If it's at all possible to change, you would be much better with a Dragon sensor'ed camera.

Even an Epic Dragon would work, it doesn't have to be a Weapon CF Dragon.

 

[Mike Kushner]

Yep - Agreed. That's why I'm not keen on the Helium if you shoot mostly 120 fps. One of those upgrades...that's actually a downgrade for 120fps on the much smaller sensor surface area.

 

[Sergio Perez]

I don't particularly agree. I also own a Weapon Helium and come from Epic Dragon. True, at the beginning it looked like I was getting inferior high speed footage in lower res in Weapon, but after some learning of the camera, its need for a proper shooting temperature black balance and with Ipp2, at 4K I'm getting beautiful results. Its going bellow 4K that It becomes to our eyes inferior to Dragon. But at 4K and 4K WS it produces great results.

 

[Marcus Friedlander]

I don't particularly agree. I also own a Weapon Helium and come from Epic Dragon. True, at the beginning it looked like I was getting inferior high speed footage in lower res in Weapon, but after some learning of the camera, its need for a proper shooting temperature black balance and with Ipp2, at 4K I'm getting beautiful results. Its going bellow 4K that It becomes to our eyes inferior to Dragon. But at 4K and 4K WS it produces great results.

Hey Sergio thanks for your input! Glad to hear I'm wrong on this one!

Thanks for proving again why testing is important lol!

 

[Russ Fill]

I don't particularly agree. I also own a Weapon Helium and come from Epic Dragon. True, at the beginning it looked like I was getting inferior high speed footage in lower res in Weapon, but after some learning of the camera, its need for a proper shooting temperature black balance and with Ipp2, at 4K I'm getting beautiful results. Its going bellow 4K that It becomes to our eyes inferior to Dragon. But at 4K and 4K WS it produces great results.

Im with Sergio on this one also. I came from Dragon and I do a lot of 120 fps work on the Helium and it does take some education. And understanding of some of the gives and takes but after you get it figured out it will produce some really nice results. If you watch the CBS Survivor reality show Season 33, 34,35, and soon to be 36 in about a month, when the host Jeff Probst talks to the cast about how or what they will be doing in the game they are about to play. All of those shots in this last season was Helium at 4K 120 fps or even some 3K at 140.. And all the Helium over crank work needed to match with Sony F800's when cutting back to the non slowmo stuff.

This next Season of Survivor Ill be using the Monstro to shoot all the second unit so we will see how the new sensor compares to the Helium seasons before. Ill keep you posted.

 

[Daniel Hurst]

I would agree with some of the above comments. I also came from Epic Dragon and was disappointed in 120fps on the Helium at first because it was different than what I expected, but once I got used to the sensor and how to properly expose and process the files I am very happy with it.

Russ- That's awesome that you are the one responsible for those slow mo Survivor shots! My kids love the show and I have always wondered if those were Phantom or RED. Let me know if you ever need some Phantom stuff! Have Flex 4K, will travel

 

[Dominic Boudreault]

Got my Red Weapon just a little while ago. Any tips on how to properly expose the sensor for 4K 120fps?

 

[Russ Fill]

Thank you Daniel, Im glad your family enjoys the show. It has taken a quite a while to work the RED in to all the corners of the show I can manage. But the results have been worth it.

To Dominic: Don't starve the sensor for light... One thing to remember when shooting say 4K at 120 is you'll always need more light than at lower frame rates and if your trying to feature other parts of the frame that are deeper or shallower than the focus area you'll need that extra light to get dof. Faster glass is something to consider. Im very lucky on the Survivor stuff that almost all of it is out side so full sun is my friend. That said using a bounce board or some sort of fill is usually needed. If you watch really nicely shot slowmo compared to not so great slowmo its really about making it look natural even though you had to pour a bunch of light on the cine to make level. So lighting is just as important when over cranking.

The R3d files are really a big help to giving the ability after something has been shot to adjust the image and get the most out of what was available.

 

[Michael Hastings]

The crop is not the problem with regard to comparative lens performance it is that the pixel pitch on Helium is smaller.

So it would require a lens with the ability to “resolve” more lines per millimeter to get the same performance.

If the lens can resolve beyond the pixel pitch of the tighter Helium (with the same depth of modulation) then there shouldn’t be a difference. If not then you would see a difference on Helium .

 

[Dominic Boudreault]

Thanks for the tips Russ!

Also a huge fan of the show. Been watching since Pearl Islands (Season 7, 2003). The time-lapse shots were quite revolutionary at the time. It inspired me to buy my first dslr and try some shots of my own. Would be awesome to see a making of or a featurette on how the show is made one day. Cheers!

 

[Björn Benckert]

Get the best 16mm glas you can find. The you get extra speed and also a image circle to fit. Using FF lenses and shooting 4k helium for example is far from optimal you only use a fraction of the lens and you dont get a as sharp and fast. Then as the pixel count goes down, its of course good to lower the compression so those few pixels left get as good coverage as possible as you dont get any downsampling to UHD if you shot 4k. So the pixels captured need to be as good as the can get. Same goes for exposure, noise becomes more prominent so good fill light and rather high exposure is needed to compensate for the lower pixel count.


So best practice:

Get a fast 16mm lens, stop it down a bit, go high on bitrate and make sure you got a lot of light.

 

[Russ Fill]

Really good advice Bjorn. I have been looking for over a year now for some good reasonable priced S16 glass. Kind of hard to justify because on the job I think I would use the 16's for most I would have to change the mount to PL and then back again so kind of a production time consuming justification.
I was wondering what the coverage might be when I go down to 4K on the Monstro. That will be my next search.