Subscribe to see EXIF info for this image (if available) ©PanasonicUSA Background Sometimes you just fall into multiple good deals and that is what we found here. not only was I able to find a used copy of the Panasonic 12-35, but got a great deal on this Panasonic 35-100 and will be using it on the Olympus EM5 Mark 2 for our review. I used to own the Olympus 40-150/2.8 PRO and will provide my thoughts on both the lenses and how they compare. Handling/Size/Weight When you think about this lens and its equivalent field of view of something like a Nikon FX 70-200/2.8 VR lens, this thing is absolutely tiny! Even against the Olympus 40-150/2.8 - we are still in the tiny realm. Subscribe to see EXIF info for this image (if available) ©camerasize.com (left to right) Nikon D700 w/ 70-200/2.8 VR Olympus EM5.2 w/ oly 40-150/2.8 PRO Olympus EM5.2 w/ Panasonic 35-100/2.8 One of the differences between the Olympus 40-150/2.8 and this lens is the material that covers the lens. Living in an area where the winters here can be quite brutal, having a barrier between your ungloved hand and the metal of a camera lens is often a welcome thing. The Olympus is an all metal construction, even the zoom/focus rings are metal. Panasonic went with a rubbery material around the rings. This will be a great benefit to me in those cold shooting months. If you remember, the 12-35 Panny also had this benefit. Subscribe to see EXIF info for this image (if available) 1/3200, f/2.8, ISO 200 @ 80mm Focusing rings are different between the Olympus and the Panasonic lenses as well. The Olympus has a manual override clutch system (which I prefer). The Panasonic, you must select manual focus or the AF+MF mode within the camera body. The focus ring on the Panasonic is well dampened and smooth for those that might have need to use it. The only switch on the lens is the Power OIS switch. I leave this on OFF as I allow the fantastic Olympus IBIS (in body image stabilization) to handle my stabilization needs. Subscribe to see EXIF info for this image (if available) 1/1600, f/2.8, ISO 200 @ 56mm The lens is weather sealed as well, so has protection against water, snow, dust and extremes of temperature. Always remember, though that weather sealing is a an all or nothing concept. Weather sealing is only at its most beneficial when you have both a weather sealed camera body as well. The EM5.2 is indeed weather sealed, so makes for a good pairing. The Olympus has a tripod ring, which is removable. It can take some getting used to if you are trying to hand hold the lens. Quite a few people either spin the foot to the top of the lens or remove the tripod foot ring all together when they don't need it. I spun it to the top. Subscribe to see EXIF info for this image (if available) 1/320, f/4, ISO 200 @ 44mm The Panasonic is 50mm focal length shorter than the Olympus on the long end and 5mm wider on the wide end. In practice, I never notice this difference in the wider end. I do find that it is taking me some time to get used to not having that extra 50mm with equivalent 300mm field of view. The Panasonic only gives you a 200mm field of view. So long as I have good light, that is not much of a concern as I do have the Olympus 75-300mm f/4.8-6.7II to handle the longer stuff. Image Quality I cannot honestly see much of a difference between the images I get from this lens against the Olympus equivalent in regards to sharpness. Straight out of camera, I might give a slight advantage in contrast to the Panasonic. However, any differences can be made up for if you have a good grasp of your post processing. This is very similar to what I experienced with the Panny 12-35 and Oly 12-40 characteristics. Subscribe to see EXIF info for this image (if available) 1/640, f/2.8, ISO 200 @ 75mm One thing to note as a "negative" on the Panasonic. On the EM5.2, I have issues with all Panasonic lenses of the shutter shock variety. I've had issues with all these lenses that I've owned and reviewed: 14/2.5, 12-32/3.5-5.6, 12-35/2.8 - the 35-100/2.8 is no different. I would ensure that any Olympus camera you choose to use this lens on should have an anti-shock mode. Another point that a lot of people will want to discuss is bokeh quality. First off, I do conceed that this is a subjective topic. Now, with that out of the way... A lot of things contribute to the out of focus rendering. Focus distance, background distance, aperture, type of subject in the background, distance to subject and focal length. I did find some instances where the Panasonic showed some nervous tendencies in some shots, it seemed less intense than when it was experienced with the Olympus 40-150 PRO. The image of the dog below is one example. The OOF background is a little nervous, but in similar situations using the Olympus, I feel the rendition would have been a bit more nervous. I take this as a fact of how a lot of modern lenses do their thing. Since more and more lenses are pushing maximum sharpness, this seems to be a more common phenomenon. Focusing Auto focusing is fast and accurate, as you would expect from a micro four thirds camera and lens of this caliber. I did notice some times, and they were very few that the 35-100 would miss focus from time to time or hunt and give up. Maybe it did that 2 times out of the 500 some images I've taken with it so far. If my memory serves, that seems pretty similar to the ratio I remember with the Olympus 40-150/2.8. This very well might be a focusing system issue. I'll do some additional test with the PEN-F and this lens to see of it reacts differently. The lens is still relatively new to me, so I just may need some more time to get used to using it. Subscribe to see EXIF info for this image (if available) 1/1000, f/2.8, ISO 200 @ 89mm Against the Olympus - while I do not have both to test head to head, I can't imagine if one were faster than the other it is most likely negligible. My gut wants to tell me that the Oly might be a bit faster. At least that is what my mind wants to tell me. Again, we are talking a relatively negligible amount for most applications here. I'm really picking nits. Bottom Line Brand new, the pro line m43 lenses are an expensive proposition if you look at them against the other lenses in the m43 lineup. However, if you look at them against other systems - even brand new they are a bargain. A new Nikon 70-200/2.8 VR II lens will run you $2100USD, where are the Oly/Panny field of view equivalents are under $1500/1100 new, respectively! I was able to pick up this Panasonic lens used for a little more than half the price of a new one! You are not going to touch even a used 70-200/2.8 lens for that price unless you go third party options like Tamron or Sigma. Subscribe to see EXIF info for this image (if available) 1/1600, f/2.8, ISO 200 @ 45mm If you look at other head to head reviews on the Panasonic/Olympus 35-150 range lenses, you'll see that most people couldn't really give one an advantage over the other from a purely "lens only" view. However, if you look at the other traits, it might make the decision fall more to one over the other. If you have an m43 camera with no IBIS, then the Panny makes sense. If you do a lot of manual focusing but don't like to have your camera in AF+MF mode, then the Oly makes more sense. Shutter shock is a reality on the Olympus EM5.2 for the 12-35, so keep in mind that used on an Olympus body - ensure that you have anti-shock enabled! You'll need to decide if you really need that extra 50mm on the long end to pick the Oly over the Panny. Weight and size wise, the Panasonic has a large advantage. Subscribe to see EXIF info for this image (if available) 1/1000, f/3.5, ISO 200 @ 47mm Unlike the wide to medium telephoto PRO lenses, the differences outside of IQ are a lot more vast and may have a larger impact on your purchasing choices. So, if you are on the fence on which to get, don't worry about AF speed or image quality. Consider them equal for all intents and purposes in those regards and look more to the other things like size, weight, cost and additional reach. I plan on shooting with the 35-100 and the 12-35 and will provide more sample images from it in the future.