Ideal zoom lens for peculiar situation?

F

Fili Gee La Padella

New member
Dear community,
I am a DP currently working on a low-budget short film which will require the anamorphic look to be achieved, somehow.
Not having much money at all, the way we'll get there is going to have to be via an anamorphic projection lens attached on to a photographic one, the latter needing to be a zoom with very peculiar characteristics, which I'll enlist down below:

- 58mm front diameter
- T2.8 maximum aperture
- Internal zoom
- 50mm-150mm or 70mm-200mm range.
- EF mount (or somehow adaptable to EF)

Does anyone know of a lens with such characteristics?
Thank you for your time.

Filippo
 
Unless you need the characteristics associated with anamorphic, e.g. elliptical bokeh, horizontal flares, optical distortion etc., it will be cheaper and easier to shoot with spherical lenses and crop the footage in post to a wide screen aspect ratio.
 
That sounds like a nightmare! If you don't have the resources to shoot anamorphic properly, then get yourself a flare filter, shoot spherically and crop to 2.39:1.

If you REALLY need the squeezed bokeh, rent a set of Dog Schidt Optics, with oval irises.

Jury rigged anamorphic adapters are a nightmare, better to shoot spherically and focus your energies on other aspects of the imagery that are important.
 
It is going to be a nightmare indeed, but I already happen to own most of the elements required in a successful makeshift-anamorphic set-up. I will only need to buy some clamps (for 45£) and a decent diopter set for around 100£. The total would be significantly less than any rental price for most lenses, and it will give me the opportunity to practice with the set-up for virtually as long as I'll like before the actual shoot, since I also own the camera.
 
What about the SLRMagic adapter and their variable diopter for focus? Seems like it should be easier to accomplish. Not sure about the zoom lens though.
 
Mitch Gross said:
You will never find a zoom with a 58mm front diameter that is also a T2.8.
Click to expand...

I understand why that would probably be a very long shot. The maximum I can compromise for is a 4.5, and I am aware of the existence of some 58mm front diameter Soligors, Vivitars and whatnot that do fall in the T3.8-4.5 range and are internal zooms. However, I don't have a clue of how these lenses would perform and they would also probably be needing some sort of adapting solution to Canon EF, which is kind of an ulterior headache. Can you recommend a slightly more modern lens with native EF mount as an alternative?
 
Greg_E said:
What about the SLRMagic adapter and their variable diopter for focus? Seems like it should be easier to accomplish. Not sure about the zoom lens though.
Click to expand...

I did look into SLRMagic but that solution, although possibly more practical, would still be significantly more expensive than going with an anamorphic adapter, since there doesn't seem to be a real rental market here in the UK for that kind of thing, and buying is obviously out of the question for aforementioned reasons. Also, the fact that ShareGrid and other similar peer-to-peer renting services haven't really taken off here yet makes this stuff insanely hard to find even if there were single individuals somewhere willing to rent them out privately.
 
If the 58mm number came from the rear diameter of your anamorphic lens, the good news is that because you are going to be shooting at a maximum of a 24.3mm image circle (Red Epic 4/3 Ana 5k), just about any zoom will do, regardless of front diameter. That's because the lenses you're looking at were designed for a full frame coverage of 43.3mm.

24.3mm [RED sensor] / 43.3mm [Lens Coverage] = 0.561 * 77mm [Front Diameter of Lens] = 43.2mm [Usable front diameter that is seen by the sensor]. Basically you'll only be using the center-most part of the lens and that is the only area that needs to be covered by the rear element of the anamorphic projector lens.

Using that anamorphic projector lens, A 70-200mm zoom will do better vignetting-wise on that image circle (see here: http://www.tferradans.com/blog/?p=13386 - it has more to do with the angle of view than the front diameter). You're also going to get a bit of a wide angle effect, so that 70-200mm will appear as a 35-100mm lens horizontally.

One of the cheapest/nicest 70-200mm zooms out there is the 1st Generation Sigma 70-200mm, which comes native in EF. Most importantly, it has fully internal zooming and focusing. Also, based on reviews, it seems to be a bit sharper in the center at 200mm than the newer versions, which have much better corner performance (of which you won't be using.)

If you're using a 2x anamorphic lens, you may want to shoot at 6:5 anamorphic, which de-squeezes to a 2.4 ratio. It also reduces the image circle. 6:5 on the Epic would put you at about a 22.77mm image diagonal.

As well, the Scarlett W has smaller pixels than the Epic ( .005mm vs .0054mm). So, 4:3 on the Scarlet W would be about a 22.5mm image diagonal, and 6:5 would put you around a 21.09mm image diagonal.

What anamorphic lens will you be using?
 
Joshua Cadmium said:
If the 58mm number came from the rear diameter of your anamorphic lens, the good news is that because you are going to be shooting at a maximum of a 24.3mm image circle (Red Epic 4/3 Ana 5k), just about any zoom will do, regardless of front diameter. That's because the lenses you're looking at were designed for a full frame coverage of 43.3mm.

24.3mm [RED sensor] / 43.3mm [Lens Coverage] = 0.561 * 77mm [Front Diameter of Lens] = 43.2mm [Usable front diameter that is seen by the sensor]. Basically you'll only be using the center-most part of the lens and that is the only area that needs to be covered by the rear element of the anamorphic projector lens.

Using that anamorphic projector lens, A 70-200mm zoom will do better vignetting-wise on that image circle (see here: http://www.tferradans.com/blog/?p=13386 - it has more to do with the angle of view than the front diameter). You're also going to get a bit of a wide angle effect, so that 70-200mm will appear as a 35-100mm lens horizontally.

One of the cheapest/nicest 70-200mm zooms out there is the 1st Generation Sigma 70-200mm, which comes native in EF. Most importantly, it has fully internal zooming and focusing. Also, based on reviews, it seems to be a bit sharper in the center at 200mm than the newer versions, which have much better corner performance (of which you won't be using.)

If you're using a 2x anamorphic lens, you may want to shoot at 6:5 anamorphic, which de-squeezes to a 2.4 ratio. It also reduces the image circle. 6:5 on the Epic would put you at about a 22.77mm image diagonal.

As well, the Scarlett W has smaller pixels than the Epic ( .005mm vs .0054mm). So, 4:3 on the Scarlet W would be about a 22.5mm image diagonal, and 6:5 would put you around a 21.09mm image diagonal.

What anamorphic lens will you be using?
Click to expand...

Dear Joshua, thank you so much for your reply, it clarified a lot of things that I really wasn't taking into account.

To answer your question right away, I was thinking of using an ISCO Ultra Star due to the more appealing MFD (of around 5 feet, according to the seller). I was also considering a Kowa, but those seem to be a bit trickier in that sense. However, I'm not gonna hide the fact that I'm really not an expert in the matter, so your advice would be much appreciated.

Also, after running a couple of tests with a Canon 70-200 f2.8 that I managed to get a hold of during the weekend, I came to the unfortunate conclusion that the range it covers won't be enough to achieve the kind of shot we had in mind. I have been looking into 10x and 12x zoom lenses within my budget, and I have been finding some very appealing options. The only issue with these is that they all come in C-mount, which I really haven't had any past experience with. I bought a very cheap Canon one with the intent of running some tests with it, but it's still on its way. Do you know wether it would be a good idea to go with these? How easy is it to adapt them to EF or PL? Also, I read somewhere that they can be easily used on a full-frame camera with a 2x teleconverter (which I also bought dirt cheap for test purposes), but in case that didn't work, would it be possible to use them natively at 2k resolution on the Epic utilising the Mysterium-X crop factor? I read of people doing it with S16 Zeiss Superspeeds and achieving pretty stunning results. Again, your opinion would be much appreciated.

Thank you very much for your time, looking forward to your reply.
 
You're welcome!

I have an ISCO as well - not the Ultra Star, but something similar.

A C-mount lens is probably not going to work. One, the flange focal distance (the space between the lens and the sensor) is very short. C-mount is around 17.5mm, while Canon EF is 44mm. PL is even greater, at 52mm. Red does has an interchangeable mount system with a flange of 27.3mm, but it doesn't look like anyone makes a C-Mount interchangeable mount. The reason is because a greater flange distance in general means that any normal adapters out there (like this one: https://www.amazon.com/Fotodiox-Adapter-C-Mount-EOS-Camera/dp/B003EAY5S6) don't hit infinity focus, and seem to be more used for macro purposes.

I don't have much experience with C-Mount lenses, though, so there may be some odd 2x teleconverter combo out there that would work. However, the old Canon TV zoom lenses aren't really the sharpest things out there. Add a 2x teleconverter, plus the softening from the anamorphic, and the image might be unacceptably soft.

As for the second reason - are you trying to get a much wider angle - is that why a 70-200 range won't work? That's almost going to be impossible with the combination (Ultra Star + C-mount zoom) you're looking at. One, the angle of view will quickly see the inside of the anamorphic lens. The ISCO Ultra Star (the separate anamorphic attachment) is a long lens, and any wide angle is quickly going to see the inside of the lens. In photography, you'll often see wide angle filters that are thinner by a millimeter. The Ultra Star, however, is somewhere in the neighborhood of 10cm or greater, so that really narrows the angle of view that will fully see through that. There are other anamorphic projection lenses that will give you a wider angle of view, but it isn't going to be super wide. You might want to look at that calculator that I linked again - it will give an approximation of when vignetting will began, based on the type of anamorphic attachment and the focal length of the lens.

On top of that, small format super zooms typically have a large front element, whether they are designed to cover a B4 (11mm diagonal), Super 16 (14.54mm diagonal), or 1" sensor size (16mm diagonal - which is most likely what the Canon you bought covers). That is most likely for the wide side of things, but it will cause vignetting attaching it to a anamorphic lens, since (unlike a full frame lens) you now are going to be using the full diagonal of the front element. Based on the lens, zooming in may help with that vignetting, but that might put you right back where you started from.

If the 2k resolution crop on the Epic is an option, you may just want to use a Blackmagic Cinema Camera or Pocket, as the end results might be similar, but the Blackmagic option would be much cheaper.
 
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