B4 on a Canon EOS

[Lee Mullen]

Anyone successfully tried a B4 with a 2x doubler on a Canon EOS camera? Seems with ML you get a 3x crop function which is really nice (650D).

 

Adapter I've ordered.

http://www.ebay.com.au/itm/181213359007?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

[Lee Mullen]

Wow an EOS forum and nobody wants to talk about them? Quite an oxymoron.

[andy lee]

I use b4 on panasonic micro 4/3 - fujinon lenses they are great with the x2 converter

not used it on my canon ever

[Tim Fraser]

Any crop on an already cropped sensor is likely to make it harder to get wide enough angles to shoot with.

 

I don't currently own any canon dslr, but made this spreadsheet up to help me decide if I could live with the crop amount.  I'm wondering if I have the crop factors (formulae) worked out correctly for the lenses listed, particularly formulae in column J.      It tries to show effective focal lengths in 35mm full frame equivalent, using raw video crop modes, for a number of Canon lenses with both the 5D iii and APS-C Canon dslrs.

 

I previously played with a Nikon V1, loved the quality of raw and ability to zoom in post, but found the short clip time in raw mode of 1 sec plus limiting.

 

B4 lenses may match up pretty well with raw crop modes in APS-C cameras.  Maybe B4 lenses and their crop factor equivalents could be built into a spreadsheet with user comments on any vignetting issues.

 

B4 to EOS adapters seem really expensive?  And some B4 zooms need power?

 

Even wide B4 zooms seem to start around 6.5mm, and if spreadsheet formulae are correct, that might get one to about 30mm eq focal length on APS-C using a reasonable 1:1 mode?  Does this sound about right?

[andy lee]

you need a B4 lens that has a pop in x2 extender built into the lens of you will just get vignetting

and you need B4 lenses made for 2/3 inch sensors not 1/2 inch sensors

[tweak]

Not sure whether you are still thinking about this, but I recently purchased a YJ18x9 Cannon B4 2/3 inch lens and adapted it to my EOS m. The result is pretty good with no vignetting or noticeable blur on the edges of the picture in 3x crop mode. I'm actually fine with using 3x crop mode as I believe for shooting video it gives a better picture and is needed if you want to shoot RAW on the EOS m... Anyway just letting you know it works.