new JVC LS300 owner- lenses

[Jay P. Kaley]

I'm considering the dumb adapters too, my early reading came across like a speedbooster or smart adapter is almost a must. My confusion on the speed booster v smart adapter: Is the speed booster 'smart' electronically also? Is a speed booster a smart adapter + focal reducer or just a focal reducer?

Q: If you use a dumb adapter and an FF lens, does the image circle 'spill over' the sides of the s35 sensor covering it fully? If so seems like that would be sort of a sweet spot of the image using the whole sensor.


I'm a bit stalled on which lenses to invest in, a little hung up on the concept of wanting to cover the whole s35 sensor.

[Luke Miller]

Q: If you use a dumb adapter and an FF lens, does the image circle 'spill over' the sides of the s35 sensor covering it fully? If so seems like that would be sort of a sweet spot of the image using the whole sensor.

The Super35 sensor is similar in size to APS-C, and a FF lens more than covers it. Just like with APS-C there is a field of view multiplier of approx 1.5x so a 20mm FF lens shows a field of view similar to a 30mm lens on the Super35 body. So yes, the sensor coverage is typically the "sweet spot" of the lens.

[Duncan Craig]

I only use dumb adapters (I have 5), and while I would like a speedbooster/focal reducer to get more out of my t1.5 Samyang set I can't justify spending £600 on it when I don't need the electronics.

I've seen very cheap focal reducers available, but not sure they are any good when it comes to Bokeh, CA and flaring etc.

Yes, AFF frame lens on a dumb or smart adapter will 'spill over' just like if you use a Canon/Nikon/Sony full frame lens on an APS-C camera.


What lenses do you already own, what kind of work do you do now/do you aspire to do with your first large sensor camera, and what support gear do you own?

[Jay P. Kaley]

Originally Posted by Luke Miller

The Super35 sensor is similar in size to APS-C, and a FF lens more than covers it. Just like with APS-C there is a field of view multiplier of approx 1.5x so a 20mm FF lens shows a field of view similar to a 30mm lens on the Super35 body. So yes, the sensor coverage is typically the "sweet spot" of the lens.

Yes, and that had been confusing me in how it relates to the adapters. If I can follow follow up- One thing I'm still unclear on about 'smart adapter v speed booster': the smart adapter just means electronics, and it doesn't reduce the circle image like the speed booster does? And the speed booster does both, electronics and circle reduce?

[Jay P. Kaley]

Originally Posted by Duncan Craig

What lenses do you already own, what kind of work do you do now/do you aspire to do with your first large sensor camera, and what support gear do you own?

I don't own any lenses, other than ENG from the 1/3" JVC. I've never bought any lenses, always used ENG shoulder form and the lens that came with it. Starting from literal scratch, makes it tougher with so many options, and exciting.

I have a Rokinon 35 that came with the camera, still can return it while I am deciding, that's part of the equation but not a major one.

The Rokinon is a good example of an issue I am having though, you can get it in MFT mount but it covers the sensor. That seems a bit unique, and makes sense to me but i don't know if any other MFT mount lenses would similarly cover the sensor, kind of been looking for that.


I shoot small events, corporate, local sports, a wedding now and then, big tripod, light kit and wireless mics. One man stuff, no major productions. It's about all things being equal I'd like to get the most out of the 'bigger sensor experience" as I can..

[Duncan Craig]

Originally Posted by Jay P. Kaley

Yes, and that had been confusing me in how it relates to the adapters. If I can follow follow up- One thing I'm still unclear on about 'smart adapter v speed booster': the smart adapter just means electronics, and it doesn't reduce the circle image like the speed booster does? And the speed booster does both, electronics and circle reduce?

Correct, yes.

[Jay P. Kaley]

Thanks for helping me clear that up, I had been missing something on those, think I've got it now.

[Jay P. Kaley]

Also was curious about much practical difference the 'clicking' aperture ring makes in to shooting video v the 'no-click' smooth motion of a cine lens? Never shot video with the click, does it affect any on camera mic and so forth.

[Earl Thurston]

Originally Posted by Jay P. Kaley

Also was curious about much practical difference the 'clicking' aperture ring makes in to shooting video v the 'no-click' smooth motion of a cine lens?

It mostly becomes a difference when you need to change aperture settings in the middle of a shot. The clicking action will often create distracting visible jumps in exposure moving from one setting to the next, whereas a non-clicking aperture allows you to make smoother adjustments that draw less attention to themselves.

[Lee Powell]

Originally Posted by Jay P. Kaley

Q: If you use a dumb adapter and an FF lens, does the image circle 'spill over' the sides of the s35 sensor covering it fully? If so seems like that would be sort of a sweet spot of the image using the whole sensor.

With MFT lens adapters, the first decision to make is whether to invest in Nikon or Canon lenses.

Nikon lenses use a mechanical lever to adjust the aperture, both on AF-D lenses (manual aperture ring) and AF-G lenses (no aperture ring). The required MFT adapter is not "smart", it is entirely mechanical and may have a built-in mechanical aperture ring for controlling AF-G lenses (not needed, but compatible with AF-D lenses as well). Precision machining is important, the best quality Nikon MFT adapter I've found is made by Metabones.

Canon lenses use an electronic iris to adjust the aperture and require a "smart" electronic MFT adapter to control the lens aperture. Some MFT adapters provide manual control only, while others integrate with the camera to provide automatic aperture control as well.

Non-speedbooster MFT adapters contain no lens elements, they couple the lens directly to the camera sensor. Most Nikon and Canon lenses, both full-frame and APS-C, will work compatibly with the LS300 at 100% VSM without vignetting. Of course, you can always use VSM to crop into the frame as desired.

Speedbooster MFT adapters have lens elements that widen the lens focal length and increase the effective aperture. For optimal compatibility with the LS300, use a 0.7X speedbooster and full-frame lenses. APS-C lenses will vignette at 100% VSM, but can be used at cropped settings. Not all full-frame lenses will work at 100% VSM with a 0.7X speedbooster without vignetting. An additional pitfall is the ND filter knob on the LS300, which may mechanically conflict with the flange of some MFT adapters.

[Jay P. Kaley]

Good information, thanks. I've learned so much about these lenses in the last few weeks it's been like a condensed photography 101, interesting stuff.

At this moment I'm leaning toward the Veydra mini prime lenses. They're MFT so don't need an adapter, manual focus which I've always used, and a feature I was looking for that made them stand out among other MFT mounts to me is they fully cover the s35 sized sensor at 100% on the VSM instead of cropping to MFT size.


I had a question about the Prime Zoom feature as it relates to focal length on lenses: If I'm shooting in HD and using a 35mm lens and I zoom in with the Prime Zoom, what's the rough equivalent to the focal length I've zoomed in to?

For example is the 35mm like a 50mm with the prime zoom all the way in? What does 2x zoom equal in lens mm?

[Steve Rosen]

The Prime Zoom, which is my favorite feature of the LS300, more than doubles the effective focal length, so a 35 would be somewhere around 80mm - 85mm in terms of field of view...

However, if you're looking for shallower depth of field, that will remain the same as the prime lens, in this case the 35...

As a side note, you can use the Prime Zoom to facilitate accurate focusing even if you just zoom in, focus, then pull back... So it works like a short parfocal zoom in that regard.

[Jay P. Kaley]

Thanks, I didn't know if the 2x translated to 2x on the lens focal length, makes sense I just wasn't sure. I asked because I'm thinking a set of 3 lenses like 16mm 35mm and 85mm with the prime zoom covers a lot of ground. I understand about DoF, would change to the longer one if wanted to emphasize that.

I think that's my plan of attack for now, looking forward to actually doing some shooting, thanks so much for the input fellas.

[Duncan Craig]

Another way to look at it is:

A 35mm lens with 100% VSM would equate roughly to 52.5mm when taking the 1.5x crop factor into account. When shooting in HD you can 'zoom' the VSM to 43% sensor coverage - roughly 2.3x, which would equate to 120.75mm on a 35mm stills camera.

Personally I never much cared for the crop factor comparisons etc etc, some directors I work with have made a fuss at the start of a job and soon stopped worrying about it.

[Duncan Craig]

Of my primes, the Samyang 35mm and 85mm are my most used lenses. When I want a wide angle I use my Tokina 11-16 which is rectilinear and fab lens - they make an even better version now.

I'm watching eBay for a used 0.71x Speedbooster then my Samyang 24mm would take some of the work away from the 11-16mm!