Super 16 Bolex RX-5

[Alain LeTourneau]

I know there's a conversion process for the Bolex RX-5 that allows one to switch back and forth between standard and super 16. Of course, you lose the turrent in place of a single C mount but I don't use the turrent anyway.

 

What Switars lenses cover super 16?

 

 

Alain

[Mister X]

Anything wider than 25mm is said to show "portholing," thus you should be safe with 25mm and longer lenses, as well as zoom lenses set above this limit. This is what I've been told.

 

Edited to add: If you only plan to use one lens mount, you really should have a Bolex SB or SBM, (rather than a RX-5, if you have a choice), converted to Super 16. You'll have a bayonet lens mount built for heavier lenses and can use an adapter for C-mount lenses.

[Alain LeTourneau]

Edited to add: If you only plan to use one lens mount, you really should have a Bolex SB or SBM, (rather than a RX-5, if you have a choice), converted to Super 16. You'll have a bayonet lens mount built for heavier lenses and can use an adapter for C-mount lenses.

<{POST_SNAPBACK}>

 

 

I only have a RX-5. Not an SB or ESB or EL. I agree...bayo would be a better option.

 

Your mention of 25mm lenses seems conservative though. I thought it would be closer to 16mm?

 

 

Thanks,

Alain

[Alain LeTourneau]

I talked on the phone with Dieter at ProCam and he thinks the 10mm Switar will cover super 16. As long as one is not hanging filters or lens hoods out off the front of the lens it will cover super 16 without vignetting, or creating a tunnel effect.

 

Not exactly what I've been hearing, but he claims that he's now heard it from a good number of his clients.

 

 

Alain

[Bruce McNaughton]

We convert Bolex cameras, all models, to Super 16 daily. You can definitely cover the super 16 frame with a 10mm Switar. The quality at the edges is low but no one is measuring that.

 

The Bolex makes an excellent super 16mm camera because there is no need to buy any new lenses.

 

When we convert a turret model we supply a new turret. The middle port and top ports are re-centred for super 16. We leave the lower port standard, so that the turret locking plug still does its work. With this locking plug and the chrome turret 'holding' mechanism in place, you have a very solid lens mount. Retaining the standard 16 port is thought to be valuable by some (for shooting standard 16) but you can extract standard 16 from the super 16 frame when you go through the mandatory telecine or Oxberry stage.

 

Bruce McNaughton

[Sam Wells]

You can definitely cover the super 16 frame with a 10mm Switar. The quality at the edges is low but no one is measuring that.

 

 

?? If the quality is low and I'm going to see it, then I am certainly "measuring" it.

 

Does it exhibit portholing, or are you talking about edge sharpness, or both ?

 

Is it a rapid falloff of sharpness in the extended S16 area ? Dependent on F stop ?

 

-Sam

[Alain LeTourneau]

Does it exhibit portholing, or are you talking about edge sharpness, or both ?

 

Is it a rapid falloff of sharpness in the extended S16 area ? Dependent on F stop ?

 

-Sam

<{POST_SNAPBACK}>

 

 

 

Bruce,

 

I too am curious about the comment you made regarding edge detail.

 

Alain

[Bruce McNaughton]

Looks like I've overstated the position. All lenses fall off in sharpness at the edges. Go to a Omnimax screen and you wouldn't give the time of day for the quality of the picture at the edges, grain swirling around like a whirlpool.

 

The 10mm Switar covers the super 16 area but JUST. The corners are just inside the darkening (vignette) circle which is the edge of the lens. If you shot a resolution chart you would not like the result at the edges. BUT on the screen, with your best eyeglasses, it is not apparent in a normal scene, especially when your attention is drawn to the centre and/or the action. I'm only talking about the lens under test conditions, not general usage.

 

Sorry.

 

Bruce

[Alain LeTourneau]

Bruce,

 

I wish there was a way to shoot super 16 for making standard 16 contact prints, and if the opportunity became available (say 2 years, 10 years, 15 years later) one could make a super 16 > 35 interneg and RP for theatrical projection.

 

I don't telecine and I edit on a Steenbeck. Then, make contact prints from negative shot standard 16.

 

I could shoot s16, cropping for 1.33, then telecine and do a DI to 35mm interneg but I still want to be able to make standard 16 prints.

 

 

Alain

[Bruce McNaughton]

Alian

 

You have only 2 choices really... Frame for standard 16 ignoring the extra picture area in the old soundtrack. Print your super 16 neg to standard 16 (this will automatically ignore the soundtrack BUT it might scratch your neg as printers are not relieved as cameras are...

 

However if you decide to release in super 16 your framings will be a bit 'lopsided.'

 

Or frame your picture so that you can extract a standard 16 image from the middle (or actually anywhere) and still use it later as super 16.

 

No magic wand... just 20% more quality (with super 16)

 

Bruce

[Mister X]

To quote from Andrew Alden's "Bolex Bible": "All the originally specified Kern lenses for the reflex H16s are usuable on Super 16, with the exception of the 10mm Switar wide-angle lens and the 86, 86EE and 86OE zoom lenses. The POE 16 to 100 zoom lens can be used with restrictions on the short focal length of the range, the PTL can show 'port-holing' effects at focal lengths less than 25mm. The MC and PTL lenses may, however, be modified to give a useable zoom range from 14.5mm to 115mm. The Aspheron is still useable, its focal length becomes 7.5mm when used on Super 16."

[Alain LeTourneau]

To quote from Andrew Alden's "Bolex Bible": [...]

<{POST_SNAPBACK}>

 

 

Yes, I too have read this as I have a copy of the Bolex Bible. However, it never hurts to ask and from the responses I have received there's not a common agreement. Alden says a 10mm will porthole, Dieter Schaeffer (and Bruce above) says soemthing different.

 

Who's right? I guess one just has to run a test.

 

 

Alain

[Rachel Oliver]

Hi;

 

I shoot with a 10mm Switar alot with my Les Bosher RX-5 conversion, It goes very slightly dark on the right hand side of the image and I stress this is VERY minimal, As most of my shooting has been for video transfer this occurs well outside the area shown by domestic TVs and even when projected is not destracting at all as it's so mild. I found my POE zoom to cover S16 completely, I have just tested the Switar 26mm and 50mm but have yet to see the results, they apparantly cover fine. I love these lenses :)

Olly

[Sam Wells]

Thanks for your report from the front lines Rachel !

 

I've never seen a 10mm Switar (mine or any other) on a test projector; I dunno literally how much sharpness falls off, only from observation (in straight 16 that is) that whatever falloff must happen pretty nicely. It *would* be nice to be able to use this lens in S16 if I go that route with my current Bolex camera.

 

-Sam

[Rachel Oliver]

Hi;

 

I think your right about the fall off being a "Nice" kinda fall off Sam, ie you really dont percieve it, I found once I started shooting with the 10mm in S16 all my "coverage" worries went away when I saw the results on normal video and TV monitors, only in overscan could I see a slight corner shadow. I'll post the results of the 26mm and 50mm Switars soon.

Olly

[Bruce McNaughton]

Rachel

 

If your 10mm is giving you a dark side , your lens port is not correctly lined up with the gate. I know that this is obvious but if it were correct, you would enjoy a full super 16 frame

 

Bruce

[Rachel Oliver]

Hi;

 

Interesting, I figured it was a quirk of the lens being Overstreched but it seems not! I must say it's so very much occuring on the absolute edge of the frame I'm not even sure if it even falls within the actual S16 ratio? For my current usage its working great, perhaps someday I shall endevour to have it looked at again..... If I start shooting for film projection especially.

Thanks for the info.

Olly

[Rachel Oliver]

Hi;

 

An update, I was able to study some footage shot with my set up with the 10mm and realised it actually has slight corner darkening on both bottom left and right side and some less top left and right side, This was viewed on a computer monitor from Final Cut which seems to overscan the image big time. I assume this is the vignette circle of the lens which is clipping the very edges of the frame, so it seems my lens centering is spot on, just that the Switar as you say only JUST manages to scrape the S16 frame. I also took a good look at edge sharpness and it's quite funny how bad it is when you really look, it just blurs out like a post effect or something (nice in a way) it just shows though that I never really noticed it before I was made aware of it!

Olly

[Bruce McNaughton]

Yes, that comes back to my original comment, that the 10mm Switar is perfectly fine for super 16 use and that you dont 'measure' the sharpness drop off when you are viewing a normal scene.

 

Interesting that you mention 'overscan' in your editing programme... The super 16 frame, when printed to 35mm (1.85:1) is used pretty well edge to edge. Most oxberry operators try to get the absolute maximum out of it, left and right. So what you get on your film you pretty well see on the big screen.

 

Bruce

[Rachel Oliver]

Hi;

 

I mean it overscans the video master I captured from, ie it has the absolute edges in frame plus even a slither of black either side in the viewing window, this is ofcourse totally cropped out by normal TVs, However this does mean that if I'm seeeing the corners of the lens in the shot then my Switar is fractionally overstretched no? I figure for a film blow up I'd have them zoom in a tad to just miss the corners.

PS anything i've shot with my Peleng 8mm has sharp and bright edges and corners on the same cam so I know what a non vignetting wide angle lens looks like too ;)

Olly

[Phil Rhodes]

Hi,

 

Your desktop edit system isn't really overscanning anything, it's just showing you the whole picture. The black bars are part of a complex and almost unknown aspect of the 601 digital video standards; the reason you don't see them on TV is that they don't come out of the composite outputs of your DV device. The area inside them is the 4:3 frame; ITU-R reccomendation BT.601 says that they may optionally contain picture, but don't have to, and may not contain anything else. Because putting picture in them would mean that manufacturers would have to get even more CCD photosites to work in order to pass QC, it's almost never done. Picture in that area would be outside the 4:3 area and represent a slightly widescreen image.

 

The only reason this is interesting is that almost nobody knows about it, including the people who wrote Adobe Premiere. Anything in PAL which tells you that the pixel aspect ratio of 16:9 footage is 1.422:1 is wrong in this regard - it's very fractional, but that number is worked out assuming that the PAL image is 720 pixels wide. It's actually only 704 - those black bars make up the rest. Yes, this means that a lot of kit does aspect ratio conversion very very slightly wrong!

 

Phil

[Rachel Oliver]

Hi;

 

Phil are you just a giant pulsating brain with eyes and hands in a room with a computer?

 

Olly

[DanStewart]

Actually he's a strapping six footer in the Brendan Frasier mould.

 

Back in London, pint, anyone?