I think it will allow around 10 seconds exposure without star trails, but needed to get inputs form anyone who had used this setup before. I couldn't find any sample photos online. From the chart here http://petapixel.com/2014/01/29/picking-great-lens-milky-way-photography/ ,the F1.4 lens is acceptable (i.e. with score >1000 as per the author), but would the F1.8 be totally useless with regard to night shots?

Also I am assuming with the 50mm lens on the 2x crop sensor, I will still get the 50mm focal length (i.e. same as if I was using a 25mm MFT lens) but the FOV will be less. Please correct me if I am wrong, to me this means that the only downside is that I will have to stitch together many images taken separately.

enter image description here

  • \$\begingroup\$ The FoV with a 50mm adapted lens will be the same as the FoV of a 50mm MFT lens unless you are using a "speedbooster" type of adapter. \$\endgroup\$
    – Michael C
    Aug 31, 2014 at 3:00

1 Answer 1


Generally, the rule of 600 is calculated with the crop factor.

On micro four-thirds, that would mean 600/50*2 = 600/100 = 6s as your longest exposure time (or 5s if you use a rule of 500) before star trails are liable to show. Any telephoto lens can be problematic for shooting longer exposures of the night sky. And yes, the longer lens will give you a much smaller FoV.

The 2x crop factor on micro four-thirds means that going wide angle on a G5 is probably going to require a native lens; and that it will be very difficult to find a wide angle lens with an adapted manual-focus lens that was designed for 35mm film. You might actually be best served using an Oly or Panasonic mft 14-42 kit lens @14mm: 600/28 => 21.4s. Or possibly consider buying the Panasonic 7-14/4 (if you win the lottery), or saving up for the Olympus 9-18 (I found one refurbished on the Oly USA website for $399) or the Samyang/Rokinon/etc. etc. 7.5mm f/3.5 fisheye for micro four-thirds.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.