bettyberg wrote:
I'm viewing on a large iMac and sharpness between the images is indistinguishable, although maybe that's due to image compression on the forum? Regardless, I am convinced the 2x TC is a viable option to start with. Appreciate you sharing your images (which are fantastic) and knowledge.
I'm glad this helped...
The 2x will do the job, it will let you down if wildlife photography becomes a long term passion. If you get hooked into wildlife photography, there are a lot of great options in lenses that can fill your "wants/needs" bucket.
Masque wrote:
I loaned my 70-200/2.8Sii + 2.0TC to a friend when we went to the Oregon Air Show a couple of weekends back. She's over at @whenshesawlight on Instagram, though I can ask for permission to post some full-size samples here.
I can say that her 24MP shots and my 600PF-fed 45MP shots were similar enough in sharpness that I'd have delivered either to a client. Heat shimmer, angles, timing, and focus accuracy were far bigger factors when picking between ours.
With heat shimmer visible with the 70-200 w 2x TC?
Not a knock on Bruce's shots, but the compression required to host them here renders them rather meaningless for critical sharpness inspection. You'd need to see the uncompressed full res for that (i.e. embedding from Flickr or similar).
OwlsEyes wrote:
I'm glad this helped...
The 2x will do the job, it will let you down if wildlife photography becomes a long term passion. If you get hooked into wildlife photography, there are a lot of great options in lenses that can fill your "wants/needs" bucket.
bruce
That might happen. I recently captured a golden-mantled ground squirrel at 200mm and it was fascinating how it sat there and looked straight at me.
RoamingScott wrote:
Not a knock on Bruce's shots, but the compression required to host them here renders them rather meaningless for critical sharpness inspection. You'd need to see the uncompressed full res for that (i.e. embedding from Flickr or similar).
Thanks Scott for the disclaimer...
You are 100% accurate when it comes to sharing image quality on a forum, Facebook, or whatever platform you choose. One must see the full res work to know if the compromise in quality is acceptable. With that stated, I'll offer the following:
1. I specifically stated in a follow-up comment that if you are going to invest yourself in wildlife photography, you will eventually outgrow the limits of the 70-200 + 2x converter as your sole wildlife lens. For my own kit, the 70-200 f2.8 w/ and w/out the 1.4x offer a level of optical acuity and performance that pairs well with the 400mm f2.8TC. If I were to plan on going light instead of heavy, I'd bring the 180-600 w/ the 24-120 and call that good enough. When I bring the 400TC, the 180-600 stays home.
2. Most... 90% of the nature photography community never prints, and if they do, it's once or twice a year. If you are going to be sharing work online and that is your primary objective, most of my gear is overkill. My 400 2.8 offers me shallow depth of field and the opportunity to drop my ISO, but for FB, IG, YouTube, FM, etc... by the time you squash your image to 2000px at 72dpi, the quality you get from the top primes can be re-created in post for a small digital presentation. My high quality optics stand out when I print, and I print my work in house and go larger than 24" via a small boutique print shop.
3. I hope that my work throughout the Nikon forum and my website speaks for my integrity when it comes to making suggestions about gear. I have fully acknowledged that the 70-200 + 2x has limits, but if you are looking for an economical entry into photographing wildlife and want to find out if that genre is for you, the lens and converter is a great place to start.
bettyberg wrote:
With heat shimmer visible with the 70-200 w 2x TC?
Yep. Hot sun, and an airport on the plains with a hot runway. It wasn't a factor for close passes, but for approach shots, 100%.
Also to Scott's earlier point, the comparison I posted uses photos I'm hosting outside this site, so you're getting actual uncompressed-other-than-camera-JPG output.
I should probably do a better comparison at ISO 64. Maybe I'll do that next sunrise over at Mt. Hood or something.
RE Atmospheric softness due to temperature differences between the ground and air above are not a lens specific phenomenon. You could have the most expensive lens in the world and a cheapo zoom, both would show a decline in sharpness at equivalent focal lengths... In fact, the images will be mushy and unusable for just about anything but an Instagram pictures for a phone.
The longer the focal length, the more profound effect due to the narrower field of view that is often referred to as "compression."
OwlsEyes wrote:
RE Atmospheric softness due to temperature differences between the ground and air above are not a lens specific phenomenon. You could have the most expensive lens in the world and a cheapo zoom, both would show a decline in sharpness at equivalent focal lengths...
I don't believe that to be quite true. Variations in the index of refraction in the atmosphere which are on a spatial scale of the aperture of the lens may be reduced by using a larger aperture, hence potentially resulting in less blurry image when a fast long lens is used wide open than when a smaller-aperture lens is used. I've seen several instances of side-by-side comparisons presented between a faster and slower long lens (both of very high quality) where the faster lens produced a sharper image at a long distance (i.e. 100 m) while the difference was smaller in the near to mid range. I believe it's not only a question of lens design (some lenses are more optimized for near or mid range performance than infinity while others are optimized for long distance) but inherently the larger aperture can help with fighting the atmospheric effects.
Additionally, the effects that degrade image quality (such as atmospheric distortion, lens aberrations, and focus accuracy) are cumulative and having a lens that has lower aberrations and focuses more accurately over long distances, can take a bit more blurring due to atmospheric effects before the images become unusable. Focus accuracy is affected by the image quality, and lens design as well as the camera's performance. A better quality, faster long lens has several things going for it.
This discussion is interesting to me for several reasons. Disclaimer: All my lenses are manual-focus through an FTZ on a Z5ii. That being said...
My longest lens is a Nikkor 300mm f/4.5 AIS (as I've said before). Not long ago I acquired a Nikon TC-14B, the version optimized for 300mm or longer. Of course I end up cropping and processing for various Internet or phone displays or for my sweetie's Auraframe or to send to friends who see them on whatever device they want. (I don't expect anything ever to be printed unless I get lucky and Audubon or similar accepts it, in which case I'll start with the original file.)
I've wondered whether the TC reduces the image quality enough to nullify the extended range. To put it another way, could a tighter, i.e. lower-pixel-count, cropping of the image w/o the TC be [almost] as good as the equivalent cropping of the optically-enlarged TC image? I need to do that experiment. Lots of variables though, for example over what range of apertures and distances. Much of the discussion above would seem to be about that exact subject, though with newer glass.
A second thought is about how it's easy to over-spend for no real return. Three of my lenses are from the old days, three and the TC were bought used, some were gifted. None of the recent purchases cost as much as $100. A superb modern AF lens would cost twenty to thirty times that. I wouldn't miss as many shots but I doubt the results would be much better.
ilkka_nissila wrote:
I don't believe that to be quite true. Variations in the index of refraction in the atmosphere which are on a spatial scale of the aperture of the lens may be reduced by using a larger aperture, hence potentially resulting in less blurry image when a fast long lens is used wide open than when a smaller-aperture lens is used. I've seen several instances of side-by-side comparisons presented between a faster and slower long lens (both of very high quality) where the faster lens produced a sharper image at a long distance (i.e. 100 m) while the difference was smaller in the near to mid range. I believe it's not only a question of lens design (some lenses are more optimized for near or mid range performance than infinity while others are optimized for long distance) but inherently the larger aperture can help with fighting the atmospheric effects.
Additionally, the effects that degrade image quality (such as atmospheric distortion, lens aberrations, and focus accuracy) are cumulative and having a lens that has lower aberrations and focuses more accurately over long distances, can take a bit more blurring due to atmospheric effects before the images become unusable. Focus accuracy is affected by the image quality, and lens design as well as the camera's performance. A better quality, faster long lens has several things going for it. ...Show more →
Some times these discussions go so deeply in the weeds, that they miss the point. I had begun to write that zoom lenses are more prone to the impact of heat distortion because they have more complex optical formulas with more air to glass surfaces which reduces light transmission. But, I chose not to go through the latter point because if your shooting conditions allow you to see heat haze while looking through a lens, your images will be mushy. There may be degrees of mushiness based on the lens, but it still is there.
Under these conditions I suggest two things... 1: Shoot a high speed burst at a wider aperture and hope that one out of ten shots results in heat waves that align "better" in the vertical plane, as you may get one shot that can be massaged in post... or 2:, Take the camera away from your eye and enjoy what you are seeing, and create a memory... not everything can be a perfect photo.
I use a 400mm f2.8, one of Nikon's best lenses and when the sun shines above snow and my angle is on the horizontal plane with my subject, no amount of optical greatness will reduce the mush that I see... my delete button and computer trash has born witness to this on countless occasions
OwlsEyes wrote:
Under these conditions I suggest two things... 1: Shoot a high speed burst at a wider aperture and hope that one out of ten shots results in heat waves that align "better" in the vertical plane, as you may get one shot that can be massaged in post... or 2:, Take the camera away from your eye and enjoy what you are seeing, and create a memory... not everything can be a perfect photo.
Very good advice. But there is a third option! Take the imperfect shot and enjoy it despite its flaws.
I know this thread is supposed to be about Z teleconverters. So I admit I am an interloper with only F-mount lenses and TC on a Z camera.. But it and few pics I posted in the Manual Focus Nikon Glass thread a day or so ago prompted me to do a study today.
I wanted to see if a TC on my 300mm f/4.5 AIS degraded the IQ more than simply resizing a cropping from a plain 300mm image by x1.4. I posted the result here:
[url]https://www.fredmiranda.com/forum/topic/929565/2682?nc=1#17097042[/url]
Spoiler alert: The TC-14B made an improvement over a resized 300mm image. A resized copping from my 200mm f/4 from the early 70's was as, or almost as, good, at least for the long distance of my test. Better than the 300mm which as done well over shorter distances An astounding result. Not an exhausting study but eye-opening nevertheless.
