RED Mini Pro Primes vs Fixed

[R.Lee]

Anyone knows if there will be shallower dept of focus with the Mini Primes as compared with the Fixed lens.

 

[Jesper Sichlau]

Yes since the f/T-stop will go as low as T1.5 for most of the primes. It will be like the DOF on a 7D at T-stop 2.8 if I'm not mistaken.

6mm T1.5
8mm T1.5
16mm T1.5
25mm T1.5
50mm T2.9

 

[Jeffrey Loewe]

Yes since the f/T-stop will go as low as T1.5 for most of the primes. It will be like the DOF on a 7D at T-stop 2.8 if I'm not mistaken.

6mm T1.5
8mm T1.5
16mm T1.5
25mm T1.5
50mm T2.9

Correct...There was also a 75mm f4 wasn't there?

I really hope there is a Canon or PL mount planned for the interchangeable.

 

[Nick Wernham]

I really hope there is a Canon or PL mount planned for the interchangeable.

Me too. I wonder if we will eventually see a zoom lens made available too or which specific zoom lenses by other manufacturers will be options. Assuming that it is indeed a 2/3" sensor (which seems to be a pretty safe assumption as far as most people here are concerned) does that mean that most 2/3" lenses will be compatible? What about other types of lenses?

 

[Nick Wernham]

Nick,

There are good discussions based on 2/3 lenses over at ScarletUser.com There are companies out there that make 2/3 C-mount glass. But if your looking to get more range, as am I, I'd maybe look into getting a Canon/PL mount to take advantage of the crop factor.

I'm not sure of other manufactures making them specifically for Scarlet, but there is 2/3 glass to be found.

Cool. Thanks, Jeffrey. My reasons for investing would be less for purposes of having more range and more because of these two reasons.

1) It is nice to have a go-to zoom lens when you need to be very quick and mobile. Basically, for those times when it's more practical to carry just one or two lenses with you for whatever reason, but you want the flexibility of a fairly wide range of focal lengths.
2) For purposes of actually doing shots that involve zooms. I don't do them often, but it's nice to have the option of using a zoom as an artistic tool.

I'd really like to go the interchangeable route to have faster glass (assuming we are given that option), but if it doesn't look like there's a viable zoom lens for the Scarlet coming any time soon I might go with the fixed (assuming that is an option).

 

[Nick Wernham]

But I mostly shoot skiing, so I like the crop factor. For what I'd shoot with the mini-primes (follow shots, lifestyles, and time lapses) the Canon's would fit in great I'd feel. Not sure if it makes sense to some, but I like the idea of a 2/3 interchangeable and taking advantage of the 2.5x crop.

Using the crop factor to your advantage sounds like a really neat way to kit out the camera for your shooting style. I shoot almost exclusively narrative stuff and I like working with wide-angle lenses for the most part. We're just wrapping up post-production on my first real project outside of film school. We shot on two perf 35mm and didn't go longer than a 50mm lens for a single shot (had 17.5mm, 21mm, 27mm, 35mm, and 40mm primes and a zoom rented). Having a 2/3" zoom lens that goes from 6mm-25mm or something like that would be amazing for my purposes.

 

[Nick Wernham]

Oh cool! So 16mm lenses have no crop factor? That's great! Thanks for the heads up, Jeffrey. Now I feel a bit ignorant. That Cooke 9-50mm 16mm t2.5 lens looks like a great option. I wish it went just a bit wider, but I'm sure I can find something.

 

[Nick Wernham]

I really hope that is the case when we receive all of the final information this evening. It would definitely open up a ton of options both in terms of purchasing glass and renting more specialized lenses for specific purposes.

 

[Matt Johnston]

From what I understand 16mm lenses should not have a crop factor.

No. they still have a "crop factor"

A 9mm lens is a 9mm is a 9mm no matter what it is bolted too.

The sensor size is going to change your field of view though.

The S16 9mm wouldn't cover S35 without vignetting but lets ignore that for a sec.

If you have a 9mm lens on a scarlet the angle of view is going to look the same as a 22.5m lens on a full frame 35mm camera if that is your regular point of reference.

Super 16mm lenses (and mini primes, and c-mount etc..) just don't have to cover as large a sensor so they can be built smaller. But MM of the lens is always the same no matter what.

So a SUPER WIDE on 2/3 is like 3-5mm or something.

 

[Matt Johnston]

Thanks for explaining. I thought 16mm was similar to 2/3 based on what I've read in regards to Scarlet. Thanks for clarifying

It is similar in field of view. But that doesn't change the lens.

So if you are used to the field of view of a 10mm lens on a 16mm camera, it will be similar on a Scarlet.

If you are used to the field of view of a 10mm lens on a 35mm full frame stills camera, it will be very different. (significantly less wide on scarlet)

For example, a 20mm lens on a 5DMKII is pretty wide. But a 20mm on Scarlet (or 16mm) is similar in field of view to a "normal" lens like a 50mm.

 

[G Lap]

It is similar in field of view. But that doesn't change the lens.

So if you are used to the field of view of a 10mm lens on a 16mm camera, it will be similar on a Scarlet.

If you are used to the field of view of a 10mm lens on a 35mm full frame stills camera, it will be very different. (significantly less wide on scarlet)

For example, a 20mm lens on a 5DMKII is pretty wide. But a 20mm on Scarlet (or 16mm) is similar in field of view to a "normal" lens like a 50mm.

The approximate crop factor FF35mm to 2/3rds is 3.75. I.e. a 50mm standard lens on a Nikon or Canon full-frame dslr would equate to 187mm telephoto on a 2/3rds Scarlet (different aspect ratios though, so conversions are approximate).

See this

http://www.abelcine.com/fov/



Sensors: Cinema (RED) v Stills Terminology & Rough Guide


This information is spread across the site in various threads. It might be useful as a rough ‘at a glance’ guide (with the caveat that some figures are approximate, not all source posts are RED official and everything is subject to change......of course). Note that aspect ratio (full sensor) is listed only as an approximate guide, for comparison with the typical 35mm stills 3:2 format.


2/3" - 3072 x 1620 - 3K
10.1x 5.35mm MX
16:9 aspect ratio, approx 11.5mm diagonal,
3.3 micron pixels, approx: 5 mpx, 3.75 FOV crop factor.

R1 - 4520 x 2540 - 4K
24.4 x 13.7mm Mysterium
16:9 aspect ratio, approx 28mm diagonal,
5.4 micron pixels, approx: 12mpx, 1.5 FOV crop factor (APS-C).

S35 - 5120 x 2700 - 5K
30x15mm MX
16:9 aspect ratio, approx 33.5mm diagonal,
5.4 micron pixels, approx: 14mpx, 1.25 FOV crop factor (APS-H).

FF35 - 6000 x 4000 - 6k
36x24mm Monstro
3:2 aspect ratio, approx 43mm diagonal,
6 micron pixels, approx: 24mpx, 0 crop factor. (FF DSLR)


Crop Factor refers to Field of View (FOV) crop factor, or Focal Length Multiplier (FLM), referenced to Full-Frame 35mm.

APS-C (Canon1.6, Nikon1.5): Canon 7D, 550D etc, Nikon D300s, D90 etc.
APS-H (Canon 1.3 crop): Canon 1D MkIV.
FF DSLR: Canon 1Ds MkIII and 5D. Nikon D3s/x and D700.

 

[Nick Wernham]

It is similar in field of view. But that doesn't change the lens.

So if you are used to the field of view of a 10mm lens on a 16mm camera, it will be similar on a Scarlet.

If you are used to the field of view of a 10mm lens on a 35mm full frame stills camera, it will be very different. (significantly less wide on scarlet)

For example, a 20mm lens on a 5DMKII is pretty wide. But a 20mm on Scarlet (or 16mm) is similar in field of view to a "normal" lens like a 50mm.

Great. That's really what I was hoping for. So that 9mm-50mm lens is, at its widest equivalent in terms of field of view to a full frame 22.5mm lens on a 5D Mark II? And at its longest point it would be quite long indeed by my standards? (Given that the longest focal length we used on my last film was 50mm on S35 which is equivalent about 85mm on full frame, right?)

If I am understanding all of this correctly it sounds like it would cover all of my needs in terms of a zoom lens. This is very exciting!

 

[Matt Johnston]

The approximate crop factor FF35mm to 2/3rds is 3.75. I.e. a 50mm standard lens on a Nikon or Canon full-frame dslr would equate to 187mm telephoto on a 2/3rds Scarlet (different aspect ratios though, so conversions are approximate).

Awww, crap. You are right. For some reason in my head I had it as 2.5x. But it is more like 3.8something. So a 10mm on a scarlet would "look" like a standard lens (40 ish mm)

 

[G Lap]

I think you were right with the 2.5....

http://www.abelcine.com/fov/

It's actually 2.6 for Super 35... and 3.8 if compared to 5dii

Not from FF35mm to 2/3ds it isn't, that conversion (which is what Matt and I were comparing) is 3.75/3.8x.

And therein lies the difficulty with 'crop factors'..........care needs to be taken over what formats are being compared.


Edit.

I see your second line now, listing both S35 and FF35mm.

 

[Nick Wernham]

So on 2/3 would RED Pro Primes and RED Pro lenses (not mini) have a 2.5x crop factor? Compared to say Canon's at 3.75? Or am I mixing it all up.

I believe that is right. Lenses that cover a FF35 lenses have a 3.75 crop factor on 2/3", I think. S35 lenses on 2/3" is 2.5. I think that is why people modify a 7D for use with cine lenses like the master primes instead of a 5D Mark II because the cine lenses would not cover the whole sensor on the 5D.

 

[Jeff Kilgroe]

So on 2/3 would RED Pro Primes and RED Pro lenses (not mini) have a 2.5x crop factor? Compared to say Canon's at 3.75? Or am I mixing it all up.

You're mixing it up. Crop factors are related to imager (sensor/film) sizes and have nothing to do with lenses. A 50mm lens is a 50mm lens, regardless of whether it was designed for a 2/3" camera, FF35 or 6x4.5, etc..

If you put the 50mm RED mini prime on a 2/3" Scarlet, you will have the exact same FOV as if you were to use a 50mm RPP on the 2/3" Scarlet or a 50mm Canon F1.2L on the 2/3" Scarlet.

I believe that is right. Lenses that cover a FF35 lenses have a 3.75 crop factor on 2/3", I think. S35 lenses on 2/3" is 2.5. I think that is why people modify a 7D for use with cine lenses like the master primes instead of a 5D Mark II because the cine lenses would not cover the whole sensor on the 5D.

No!!!!! Focal length is always focal length and crop factors do not change based on lenses. A crop factor relates one sensor size to another. period.

 

[Nick Wernham]

My mistake. I suppose what I meant is that if you used a 10mm Canon L-series lens on a 2/3" sensor like the Scarlet with a Canon mount it would have the same field of view as a 37.5mm lens on a 5D Mark II. Apologies for my ignorance and for using incorrect terminology.

 

[G Lap]

Easy Jeff :smile:

........................A crop factor relates one sensor size to another. period.

Agreed, and that's what the original conversation was about........Matt did point out the '10mm is a 10mm is a 10mm' earlier.

 

[G Lap]

Anyway, enough of this for now............Scarlet should be here in less than five-hours .