Zooming vs. speedramping, which looks better?

J

JimS2

Member
I am planning out a project, where I want to do fast crash zooms in some shots. However, it's difficult to find a zoom lens under 1000 USD that can do a big crash zoom successfully. I was advised by another filmmaker, if I want it simulate a fast crash zoom to just move the camera over a large amount of land on a gimbal, and then speed it up fast in post, and add motion blur, if necessary.

However, the disadvantage of doing this, is that this will speed up the actors' movements as well compared to a zoom. But he says it will be fast and people will not notice the actors movements sped up during. He also said that a speedramp looks less cheesy than a zoom because if you do a crash zoom, it screams 1980s. But wouldn't the same be applied to a speedramp? Won't people look back at a speed ramp and say those speed ramps look so 2000s?

So I am wondering if one is better than the other for this type of shot effect? Thanks for any input! I really appreciate it!
 
It doesn't matter what people think; everyone always has something to say about everything.

The technique recommended will look different than a traditional crash zoom, but both may work depending on your purpose, content and execution.

For a crash zoom to be effective, you'll need a parfocal lens (unless you're okay with refocusing quickly after the crash).

Older, smaller sensor cameras with interchangeable lenses - such as those from the 1980s and beyond when that was seen a lot from them - were all parfocal (at least most of them). Today, the sensors are bigger so the glass options are limited unless you have $$$.

Do you have a camera in mind? Because you can rent a fixed-lens prosumer system for less than $100 for the the day and have crash zooms. [With that said, you could also rent nice parfocal lenses, but the overall cost may not be worth it depending on the filming schedule.]
 
Oh okay thanks. I was thinking if using the Blackmagic Pocket cinema camera most likely. I tried some zooms on a non-parfocal but people say that it looks weird how it goes out of focus during. I try to as I do the fast zoom, but the zoom is so fast, that I keep failing to refocus fast enough with it. The focus cannot keep up with the fast speed of the zoom. I usually don't like renting in the past, because that would limit which days I could shoot, where as if it is a lens I could own, then I can pick any shoot day for the cast and crew and not have to worry about it being on the rental store's schedule, like in the past, if there is any lens that can work for that?

But it depends on what looks better between a crash zoom and speed ramp. What I want to do is an actor peaks around a doorway, and it's a close up of his face. Then I want to move the point of view back really fast, to reveal all the men waiting to ambush him, if that makes sense?

So I can do a fast crash zoom to reveal the ambush, or I can physically move the camera back with a gimbal, and then speed it fast in post, if one sounds better than the other?
 
Out-of-focus during? No one notices that within the 1 second a crash zoom usually lasts.

But out-of-focus after and then pulling it back into focus can be a problem for viewers unless they are used to it (The Office).

It's totally fine if the lens is parfocal. This is one of your best options:

https://www.bhphotovideo.com/c/product/1507682-REG/dzoptics_dzo_6226611a_20_70mm_t2_9_m4_3_lens.html

Maybe there are also some vintage parfocal zooms you can find on eBay (but I don't know any).

IMO, I think it's easier imagining the move than successfully creating it with the gimbal. It would have to be perfect otherwise I don't know if you'd be happy with the results. Only way to know for sure is to test something similar with some friends.
 
that lens is m43 - is he talking about pocket 6k or 4k?

also, he's probably describing a huge move. that lens is less than 4x zoom range. he probably needs 10x or more

i did a lot of crash zooms in eng shooting with my tamron 18-270

it has a true manual focus ring with hard stops. if you set your focus marks in advance (and especially if someone else pulls it for you), you could probably nail the zoom and focus rack simultaneously

and they make a 16-300 now. sweet!
 
'Blackmagic Pocket Cinema Camera' is the name of the first one ever, so I imagine it's that one, but I guess it wouldn't be the first time someone left out the 4K or 6K in their description of the new ones.
 
Oh sorry, I wasn't sure if I am going to get the 4K or 6K for the project, but I might get 4k, to save money.

Out-of-focus during? No one notices that within the 1 second a crash zoom usually lasts.

But out-of-focus after and then pulling it back into focus can be a problem for viewers unless they are used to it (The Office).
Click to expand...

But it going out of focus noticeably when I try to pull focus fast. Here is a test I did:

Out-of-focus during? No one notices that within the 1 second a crash zoom usually lasts.

https://www.youtube.com/watch?v=DNfzSxFq9aw&feature=youtu.be

I can't nail the focus fast enough. This was done on a Canon 70-300mm lens just for testing so far, but still cannot nail the focusing myself.
 
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It's not clear if you're saying you're pulling focus at the end in that test?

My guess would be you're not and that's how that particular lens is designed, it's normal. (If you are, that's pretty fast!)

A real parfocal lens wouldn't do that. You would zoom in on the red door, focus, and then when you would pull out everything would be in focus with no blurry blob at the end of the pull.

You wouldn't have to do anything but move the zoom ring.

P.S. I keep using the word 'parfocal' but it just hit me you may not be familiar with the term. Are you?
 
Oh okay thanks. Yes I know what a parfocal lens is, but thanks for point it out :). Well perhaps I just need to learn to pull focus better with a non-parfocal lens? I marked the spots where to focus from the start of the zoom at point A, to the end of the zoom at point B. However, it still goes out of focus and then back, while I focus from point A to point B, during the zoom.
 
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The difference in focus is too major to not be noticeable...going from 300mm to 70mm, vice-versa.

I actually meant to add above that the test almost looks like auto-focus. If that was you manual focusing, I think that's as good as it will get unless someone is pulling focus for you during the 1 second pull out/in or you somehow use both hands and do it yourself.

The point mentioned above about the focus marks is useful. If you have someone working with you then he or she can pull the focus from point A to point B while you zoom, but it's really the last resort (unless you have wireless focusing).
 
As long as the lens is not focus-by-wire, you should be able to set focus marks (and zoom marks) and adjust the focus as you adjust the zoom. But it would be beastly difficult to do all that by yourself. Better to have someone else racking your focus (with the Marks on tape on the barrel or the follow focus) whilst you pull the zoom ring
 
Oh okay thanks. It turns out this particular lens is focus-by-wire. Even on manual focus it is I think. Would I still be able to use it, or is that out of focus part in the middle unusable? One person said they thought it looked cool and adds to it, but does it?
 
Um, rent a Fujinon MK lens in MFT mount? https://www.lensrentals.com/rent/fujinon-mk18-55mm-t2.9-for-micro-4-3 IMHO, the hunting for focus at the end of
a crash zoom is going to look lame.

Doing the gimbal thing would be a dolly shot, totally different perspective than a crash zoom. Two different techniques for two different end effects.
You have to decide which. If it was important to me, I would take Abe's advice and shoot tests and compare. They're going to look and feel pretty different.
 
Personally I'm not crazy about that out of focus moment. It takes me out of the story a bit.

What is that lens?
 
The lens is a Canon 70-300mm. But I can get another lens for the real zoom shot, since I was just doing tests. However, I would need a lens that can do it without going out of focus that can cover at least 200mm of zooming though, for the shot I think.
 
Remember that the difference in mm is proportional. What matters is the ratio of telephoto focal length to wide-angle focal length. 300/70 = just over 4x. Another 4x zoom lens can create the same framing change (albeit with different perspectives).

So, I believe that the Canon 18-80 could achieve a similar shot as what you showed, but looking way more wide-angle

PS is the shot you showed autofocus?
 
Oh okay thanks. No I was pulling focus manually in the shot while zooming, it's just that I wasn't successful at it. But no autofocus was on.

It also occurred me to, I am going to want a 300mm lens anyway for some other shots, where I want to high compression, so I need to zoom into at least 300mm to get that compression, which is why I already have a 300mm for those shots. So if I get a new lens, is it possible to get one that can zoom up to 300mm but where I can pull focus during a zoom and it won't go out of focus?
 
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