Idly thinking about an EF speedbooster

[kye]

I'm idly contemplating buying a Metabones Ultra 0.64x speed booster for my GH7.  This would take me into the world of EF for the first time.

I'm completely familiar with speed boosting and crop factors and all that jazz, with years of experience from my 0.71x M42 to MFT speed booster and (many) M42 lenses.

What's the deal with speed boosting to EF?  
Is the Ultra 0.64x worth it over the normal 0.71x adapter? (they seem to be similarly priced used).
Is there a different one I should consider (other than Metabones)?

Essentially I'd be getting it to shoot shallow DOF (like I do with my M42 Takumar 50mm F1.4, etc) but with more modern / cleaner results as M42 lenses are quite vintage and far dirtier than fast EF glass, especially when shooting wide open.  AF is of little importance to me, so I'd be expecting manual focus.

[stephen]

I've used Metabones Ultra 0.64x speed booster with my Blackmagic Pocket 4K. Compared to 0.71x is moves your crop factor a tad closer to FF 0.64x -> 1.28x vs 0.71 -> 1.42x  and gives you a little bit more light (1/3 stops) and a little bit more DOF. You can use it not only with Canon EF but all lenses which have flange distance > than Canon EF. Like Contax Yashica, Nikon, m42, Pentax. Biggest issues for me is the weird crop factor. x2x0.64 = x1.28. Now I want an angle of view equivalent to 35mm in FF. Which lens should I use ? 28mm as 28x1.28=35.84 And so on. That's why I moved to FF. 35mm is 35mm no matter if lens is vintage or modern, plus I can use Minolta MD, and a bunch or other brands and bayonets. No need for speed boosters. Lens is used exactly as it was intended by the manufacturer. Sensor if big and has no problem with low light. For vintage lenses and in general for lenses alone FF is the way to go for me. I was tiered to calculate crop factors and deal with speed boosters.

[eatstoomuchjam]

7 hours ago, kye said:

What's the deal with speed boosting to EF?  
Is the Ultra 0.64x worth it over the normal 0.71x adapter? (they seem to be similarly priced used).
Is there a different one I should consider (other than Metabones)?

The difference is not huge.  When wide open on very fast lenses, you're more likely to see some speed booster artifacts with the 0.64x.  Whether those artifacts are acceptable is personal taste.  If the prices weren't similar, I'd just take the cheaper one.

I was also surprised to find that the 0.64x covers the slightly small S35 sensor in my Z Cam E2-S6G.

Anyway, as far as other brands, I think that Kipon's focal reducers are well-regarded.  Otherwise, most of the third-party ones are skippable/don't seem to be too good.

7 hours ago, kye said:

Essentially I'd be getting it to shoot shallow DOF (like I do with my M42 Takumar 50mm F1.4, etc) but with more modern / cleaner results as M42 lenses are quite vintage and far dirtier than fast EF glass, especially when shooting wide open.  AF is of little importance to me, so I'd be expecting manual focus.

FWIW, you can also have your cake and eat it with a focal reducer, if you want.  Pentax K, Nikon F, Leica R, Olympus OM, and M42 lenses (including your Takumar) can all be adapted to EF mount.  I've also thought about building a recessed M39 adapter since it would be theoretically possible on any camera without a mirror assembly (M39 is 28.8mm and EF is 44mm, but I have several M39 lenses with controls near the front and that are skinny enough that they could just sit further back in the EF mount).

Anyway, for EF lenses otherwise, do you know which you're considering? 

[kye]

3 hours ago, stephen said:

I've used Metabones Ultra 0.64x speed booster with my Blackmagic Pocket 4K. Compared to 0.71x is moves your crop factor a tad closer to FF 0.64x -> 1.28x vs 0.71 -> 1.42x  and gives you a little bit more light (1/3 stops) and a little bit more DOF. You can use it not only with Canon EF but all lenses which have flange distance > than Canon EF. Like Contax Yashica, Nikon, m42, Pentax. Biggest issues for me is the weird crop factor. x2x0.64 = x1.28. Now I want an angle of view equivalent to 35mm in FF. Which lens should I use ? 28mm as 28x1.28=35.84 And so on. That's why I moved to FF. 35mm is 35mm no matter if lens is vintage or modern, plus I can use Minolta MD, and a bunch or other brands and bayonets. No need for speed boosters. Lens is used exactly as it was intended by the manufacturer. Sensor if big and has no problem with low light. For vintage lenses and in general for lenses alone FF is the way to go for me. I was tiered to calculate crop factors and deal with speed boosters.

Thanks for the info.  

They're definitely not for everyone, but I'm more than comfortable using them and all the associated math.  I'm even a fan of the in-between focal lengths.  I discovered that I absolutely adore shooting with my 42.5mm F0.95 lens paired with my Sirui 1.25x anamorphic adapter, and that's equivalent to a 68mm F1.5 lens on FF.  50mm would be too wide and 85mm too long - so the fact that FF lenses are exactly 50mm or 85mm on FF is actually a disadvantage for me.

The economics of it are also pretty straightforward, I can get one of these for half of what a Panasonic S9 or OG S5 would cost, and it means I don't have to carry around two bodies etc either.

1 hour ago, eatstoomuchjam said:

The difference is not huge.  When wide open on very fast lenses, you're more likely to see some speed booster artifacts with the 0.64x.  Whether those artifacts are acceptable is personal taste.  If the prices weren't similar, I'd just take the cheaper one.

I was also surprised to find that the 0.64x covers the slightly small S35 sensor in my Z Cam E2-S6G.

Anyway, as far as other brands, I think that Kipon's focal reducers are well-regarded.  Otherwise, most of the third-party ones are skippable/don't seem to be too good.

FWIW, you can also have your cake and eat it with a focal reducer, if you want.  Pentax K, Nikon F, Leica R, Olympus OM, and M42 lenses (including your Takumar) can all be adapted to EF mount.  I've also thought about building a recessed M39 adapter since it would be theoretically possible on any camera without a mirror assembly (M39 is 28.8mm and EF is 44mm, but I have several M39 lenses with controls near the front and that are skinny enough that they could just sit further back in the EF mount).

Anyway, for EF lenses otherwise, do you know which you're considering? 

I think focal reducers and adapters and front anamorphic adapters all provide a myriad of potentially interesting options, which I brought up in the Adapters are BACK.. and better than ever! thread.

The main candidate would be a 50mm F1.4 to be a 64mm F1.8 equivalent lens for shooting "night cinema".  This would be to replace my M42 Takumar 50mm F1.4 + SB combo (which is very vintage and has distracting bokeh and isn't great on the sides) and the 42.5mm F0.95 + Sirui 1.25x combo (which is heavy and also isn't great on the sides).

Between Canon and Sigma and Zeiss I'm sure there will be a range of lenses that are as pristine as I'm willing to pay for.

I've found that the 65-70mm range is really great for crowded street work like markets etc where you can shoot a range of compositions from wides to portraits to macros, and is also great for shooting wider shots on the other side of the street.  I'm also wondering if a wider fast prime might be useful too, so maybe a 24/1.4 (which would be a 31mm F1.8 equivalent) or a 28/1.4 (which would be a 36mm F1.8 equivalent) might also be interesting but I feel like I'm just getting started with this style of shooting.

[kye]

I could even sacrifice a small amount of aperture and go with the Sigma 50-100mm F1.8 zoom (equivalent to a 64-128mm F2.3), which would have all the benefits of a zoom.  It's a pity there isn't a mid-range offering in that series so I could go both wider and longer than the 50mm mark.

There's always the Canon CN-E 31.5-95mm T1.7 zoom, which would be perfect if it wasn't 7.8lbs / 3.5kg, enormous, and USD24,000!