Test: KIPON Baveyes 0.7x LPL to Mamiya 645 Focal Reducer

[Tim Sessler]

Hi everybody -

I recently bought a Kipon Baveyes 0.7x focal reducer for my Mamiya Sekor C 645 lenses. The 80mm was the lens I was most excited about as with the speedbooster it should match one of my all time favorite lenses: a Canon FD 55mm. Funny enough all the Mamiyas felt much longer than what I would have expected. The 35mm should match a 24, the 45 a 32 and the 80 a 55.

To verify my suspicion I used a PL to LPL adapter, which would allow me to quickly swap from the LPL Kipon focal reducer to my rehoused Canon FDs.

Here is what I found:







As you can see the Mamiyas are significantly tighter. In fact the actual crop factor/focal reduction seems to be closer to 0.8x.

Which means the 80 isn't matching a 55 but rather 64mm and the 35mm isn't as wide as 24mm but much rather matching a 28mm.

Here is a full write up with more samples (both from me and also shots from other lens tests):

http://brooklynaerials.com/blog/2022...ue-crop-factor



This seems to be a pretty big deal and very misleading advertising on Kipon's end. I am surprised nobody else has pointed this out (at least I could not find anything along those lines).

I'd be curious if this is the same for the other KIPON Baveyes adapters like the LPL to Hasselblad V Mount or the Baveyes focal reducer made for RED DSMC2.




Let me know what you think and if you've seen similar discrepancies with focal reducers.



Cheers!

 

[Phil Holland]

I oddly made my own a long, long time ago for DSMC2 bodies, but I'll eventually take a look at this. Generally they have said it's a 0.71X, but there's not much explanation from there.

Glad you enjoy the Mamiyas as much as I do. They are special lenses.

 

[Zack Birlew]

I have one as well for toying with medium format lenses, it's great! While it's not 100%, I know it's the closest thing there is short of someone finally making a full medium format sensor and not the slightly bigger than 35mm sensors found in the Fuji GFX and Hasselblad cameras. There are some very interesting medium format lenses that don't have mainstream adapters as of yet, thankfully the eBay DIY crowd picked up on them and I know the speed booster would actually be more useful for those but it is what it is for now.

Do note, long telephoto lenses like the Mamiya 500mm and Pentax 67 500mm will not work as it vignettes. I haven't gotten my hands on a 400mm medium format lens to test but 300mm looks to be the maximum with the Kipon. Also, the only other solution I can think of is to get a 1.4x or 2x teleconverter for whatever camera you're using, mine being E mount is a bit disappointing as Sony is the only one that makes them and they are quite pricey, as that could be the optical trick to get around the vignette. Still, as some have said in a previous thread, it would be more of a bonus to use the 500mm lenses without the speedbooster as you're going for reach anyway but until I can get a teleconverter to test, I have nothing to compare it to.

 

[Tim Sessler]

I oddly made my own a long, long time ago for DSMC2 bodies, but I'll eventually take a look at this. Generally they have said it's a 0.71X, but there's not much explanation from there.

Glad you enjoy the Mamiyas as much as I do. They are special lenses.

Right - I forgot about that. I remember seeing you tease your mounts but never saw any results. Did yours match the 0.71x/0.7x claim?

 

[Phil Holland]

Right - I forgot about that. I remember seeing you tease your mounts but never saw any results. Did yours match the 0.71x/0.7x claim?

We used the correct optics. I'm wondering if Kipon is using one of their 0.8 optics in here potentially either on accident or otherwise.

 

[Tim Sessler]

We used the correct optics. I'm wondering if Kipon is using one of their 0.8 optics in here potentially either on accident or otherwise.

Curious if you ever did any direct comparisons with (hypothetically) matching primes?

I was wondering about this too - maybe my KIPON had a defect but that theory doesn't seem to make sense, as all other tests on the web that I could find show similar discrepancies.

 

[Phil Holland]

Curious if you ever did any direct comparisons with (hypothetically) matching primes?

I was wondering about this too - maybe my KIPON had a defect but that theory doesn't seem to make sense, as all other tests on the web that I could find show similar discrepancies.

I didn't use their optics, so that would be a wash in my case. I think what would be worth doing is contacting them and seeing if it's actually a .8 or .71 and go from there. Next free moment I have I'll do a quick comparison of their adapters I have here.

 

[Bruce Allen]

I think I can help as I also have one (think it's the v1 M645-LPL version).

Only issue is I'm slammed right now - my friend and I currently doing all nighters on post on this commercial we directed.

Thanks for testing this, this is very good info to know!

Bruce Allen
www.bruceallen.tv

 

[Michael Lindsay]

Interesting thread… We have the adapter but also have a TLS Mamiya focal length reduced set (little crap blog on them from me)… I can check both.

I will try have a look this weekend.. I did do a rough test when selecting my lenses for the project and did notice they seem slightly wider with the wide ones but figured this was simply (as I was comparing to ARRI signatures) the product of them being less rectilinear and (to a lesser extent) having their entrance pupils further back..

I also noticed the more modern N versions of the 45mm was quite a bit tighter… so maybe it is not the Kipon adapter but a few different factors playing in…

 

[Tim Sessler]

Interesting thread… We have the adapter but also have a TLS Mamiya focal length reduced set (little crap blog on them from me)… I can check both.

I will try have a look this weekend.. I did do a rough test when selecting my lenses for the project and did notice they seem slightly wider with the wide ones but figured this was simply (as I was comparing to ARRI signatures) the product of them being less rectilinear and (to a lesser extent) having their entrance pupils further back..

I also noticed the more modern N versions of the 45mm was quite a bit tighter… so maybe it is not the Kipon adapter but a few different factors playing in…

Oh thats fascinating. Would be super interesting to see how they compare. I double checked with TLS and they are using the Kipon Baveyes 0.7x for their rehoused sets. So in theory they should be all the same.

Very interesting to hear RE: 45mm being different. From everything I've heard all the different versions are the same lens design with only coating changes. Odd that the 45 would be noticeably different.

Curious to hear what you find in your testing this weekend!

Thanks!

 

[Michael Lindsay]

Hi Tim

It is annoyingly more complicated than just coatings… the 45mm was a complete optical change others have tiny optical changes and some just coatings.

I really wanted to pick the old C lenses but with the 45mm for example it was just not possible due to colour.. the new 45mm also flares much better! I am having TLS detune my 45mm (32mm) as it is maybe a little too good…

just a few of the 45mm lenses I looked at…

worth it in the end but annoying to do

Oh thats fascinating. Would be super interesting to see how they compare. I double checked with TLS and they are using the Kipon Baveyes 0.7x for their rehoused sets. So in theory they should be all the same.

Very interesting to hear RE: 45mm being different. From everything I've heard all the different versions are the same lens design with only coating changes. Odd that the 45 would be noticeably different.

Curious to hear what you find in your testing this weekend!

Thanks!

 

[Drew Kass]

Tim - I tested the Mamiya's on the Mini LF and found your claim to be true. To my eye the Baveyes 0.7x appears to be more of a 0.77x (roughly). See attached frames.

 

[Kemalettin Sert]

Tim - I tested the Mamiya's on the Mini LF and found your claim to be true. To my eye the Baveyes 0.7x appears to be more of a 0.77x (roughly). See attached frames.

thanks for doing this..Against Signature primes, Mamiya looks soft AF...And then Mamiya 35mm compared to 24mm and that FD 24mm looks like the bottom of a coca cola bottle. Imagine the hype on FDs lol.

 

[Drew Kass]

Looks like Kipon's new Baveyes models are 0.8x

 

[Zack Birlew]

Coming back to this thread, yeah, like I said before, the Kipon is not 100% but until somebody makes a digital cinema 645, 6x6, 6x7, or 6x9 camera, there's just going to be some concessions when adapting legacy medium format lenses. The 80mm 1.9 is an unfortunate case as I can tell from images online that the 1.9 should look better than it does with the Kipon but stopped down it shapes up and the 80mm 2.8 is actually the more sensible buy if you want clarity the whole way through the aperture range. However, for dreamy close ups and extreme low light, the 80mm 1.9 is the only game in town aside from taking a 0.1 drop to F2 with the wildly expensive Contax 645 80mm F2 or the also pricey Noritar 6x6 80mm F2 (although Norita lenses don't currently have a speedbooster option and they don't adapt to Mamiya 645, Pentax 645 , or Contax 645 so it is what it is).

Remember, while the Canon FD and Arri cinema primes show similar looks and sharpness, the medium format lenses have an aesthetic that 35mm lenses can't quite grasp. Again, until somebody makes a native digital cinema 645+ medium format camera or Kipon perhaps improves their speedbooster formula, there's going to be some caveats with using medium format lenses on smaller sensors.

 

[Phil Holland]

The 80mm 1.9 is an unfortunate case as I can tell from images online that the 1.9 should look better than it does with the Kipon but stopped down it shapes up and the

I've mentioned a few times in regards to using Expanders and Focal Reducers, best to stop down at least a stop if you want to take some of the optical adapter out of the equation when it comes to optical performance.

I own various sets of 645 glass that I enjoy a lot on VV, but most of the time I'm using the straight lens as there are benefits to all that. It is interesting to see various rehousing efforts with an integrated focal reducer however to gain that stop. Works well if that's the goal.

But for the picky and real discerning, most go with the straight glass on all lenses.

 

[Kemalettin Sert]

I've mentioned a few times in regards to using Expanders and Focal Reducers, best to stop down at least a stop if you want to take some of the optical adapter out of the equation when it comes to optical performance.

I own various sets of 645 glass that I enjoy a lot on VV, but most of the time I'm using the straight lens as there are benefits to all that. It is interesting to see various rehousing efforts with an integrated focal reducer however to gain that stop. Works well if that's the goal.

But for the picky and real discerning, most go with the straight glass on all lenses.

But kipon claims optical adapter makes lenses sharper ie. Mamiyas in this instance.

By the way anyone tested newer version of the focal reducer they released? 0.8x version

 

[Phil Holland]

But kipon claims optical adapter makes lenses sharper ie. Mamiyas in this instance.

By the way anyone tested newer version of the focal reducer they released? 0.8x version

Center frame a focal reducer will shine. Outside of center through field out to edges is where the issues really come into play. Plus the enhanced vignetting, enhanced distortion, etc.

In a perfect world, the thing to do would be designing purpose designed focal reducers on a per lens basis. That would be rather expensive however.

I own about 75% of the reducers Kipon has ever made.

It's all about choice really. I mean people are now rehousing medium format glass with integrated reducers and are happy with that concept and I think that's pretty cool. I am likely the most picky when it comes to stuff like this. We went through a few years of people just praising speed boosters without mentioning the drawbacks. Always be weary when you see a bunch of stuff suddenly pop up on YouTube during a marketing splash.

In this case, it's all about the balance of the gains versus the loses.

Gains:
- increased FOV for a given focal length on your format size
- increased light transmission via reduction
- increased resolution center frame

Loses:
- Increased chromatic aberrations near edge and corner frame
- enhanced vignetting
- enhanced distortion
- potentially some unwanted flare characteristics
- likely a slight lost in image contrast, usually negligible.

One of my personal main reasons to use larger format optics on a smaller format is to get less vignetting, shooting within a sweet spot of the lens with lower chance of aberrations, and avoiding cats eye bokeh. I have reducers/speed boosters and use them for their strengths. But you also lose a bit of the interesting bits you may get with larger format optics.