I bought a Sony 400-800 to pair with an A1 towards the end of March. When I first took it out and got home the results were far below what I’ve been used to seeing, and nothing like the reviews of the lens I’d read.
Of the 1500 shots I took that day, maybe 100 were what I’d consider usably sharp. Now I was coming from a Nikon 600 PF so I was expecting some fall off, but nothing like what I’ve been seeing. I chalked it up to the additional 200mm and weight and I needed to work on technique.
Yesterday I took the lens out with me on a wildlife photography trip. I kept chimping to see the results and again was just not seeing anything close to the performance I’ve been accustomed to in the past. So I tried f/9 and all of a sudden I was getting sharp images. I started going back and forth and sure enough the shots at f/9 blew f/8 away, BUT every now and again a shot at f8 would be fantastic.
When I got the shots home yesterday I noticed it’s not a sharpness issue at all at f8, it appears to just be missing focus, just enough to muddy the image. Has anyone seen anything like this before?
I thought I was losing certain shots to shutter shock or missed AF until I switched to the A9iii, and it became blindingly obvious SS was too low in certain situations because the A9iii AF hit rate is like 99.9% at high SS, the camera has no shutter and yet some shots in a burst sequence were still blur.
Some of my mental shutter speed "look up tables" learned when shooting a 4 / 6 / 8MP cameras had to be un-learned.
If you are shooting BIF start at 1/8000s. If the light sucks you can use 1/3200s but expect some shots to be blur.
I also made a post about how AF at 200/2.8 is considerably better than 200/5.6. The amount of light hitting the sensor does make a big difference to autofocus performance on mirrorless cameras.
The 600GM will have an easier time auto-focusing in poor light than a 800mm f/8, because its a f/4.
icantbebigwill wrote:
I bought a Sony 400-800 to pair with an A1 towards the end of March. When I first took it out and got home the results were far below what I’ve been used to seeing, and nothing like the reviews of the lens I’d read.
Of the 1500 shots I took that day, maybe 100 were what I’d consider usably sharp. Now I was coming from a Nikon 600 PF so I was expecting some fall off, but nothing like what I’ve been seeing. I chalked it up to the additional 200mm and weight and I needed to work on technique.
Yesterday I took the lens out with me on a wildlife photography trip. I kept chimping to see the results and again was just not seeing anything close to the performance I’ve been accustomed to in the past. So I tried f/9 and all of a sudden I was getting sharp images. I started going back and forth and sure enough the shots at f/9 blew f/8 away, BUT every now and again a shot at f8 would be fantastic.
When I got the shots home yesterday I noticed it’s not a sharpness issue at all at f8, it appears to just be missing focus, just enough to muddy the image. Has anyone seen anything like this before? ...Show more →
Since f8 kicks in as the maximum aperture at various zoom settings (and it may kick in quite early), two possibiities are that: 1) at that aperture you are getting the worst normal performance of the lens; or, 2) at that maximum aperture, there is some degree of miscentering, tilt, or misadjustment in the lens that is more impactful than it is at smaller apertures--it is a zoom lens, which almost inevitably have some tilt.
Yoy could very carefully and with a tripod do Fred's lens-centering test at f8 and at f9 at a zoom setting where f8 is the maximum aperture and then compare the two for miscentering or tilt effects on the image.
If you find a problem that is unacceptable to you, then you would need to get the lens serviced by a tech that takes the problem as real and has the skills to fix it.
Another possibility (that seems less likely but possible) is that the focusing accuracy is different at f8 and at f9, either because of the very slight change in depth of field between those two apertures (especially at longer zoom ranges where f8 is the max ap), or because the slight reduction in contrast and resolution at the max ap affects the accuracy of the AF system.
Also, make sure your A1 and the lens have current firmware.
Sounds like the copy of the 200-600 I used to have. Even though some of my 600 f/6.3 shots looked nice and sharp, most of the time if I shot at f/7.1 it made a crazy difference.
I know other copies of the 200-600 were better than mine at 600 f/6.3 and I bet there is similar variation with the 400-800 at 800 wide open.
I certainly wouldn't expect anything on par with the 600PF which is a super sharp lens even wide open. I even wonder if a 600PF shot cropped to 800mm FOV would look better most of the time than a Sony 400-800 shot at 800??
Closing down 1/3 stop commonly results in a little better contrast with zoom lenses, but inconsistent AF seems like a different issue possibly a bit of sticking somewhere. My 200-600 is sharp in the center at f/6.3 but the periphery gets better to f/8. AF was unreliable on the a7rIV but good on the a7rV. Hopefully your lens it is still under warranty. I'm still on the fence about buying a 400-800.
I have noticed this also, but I have chalked it up to technique. A small bird against a busy background at a distance, it is necessary to wait for the eye Af box to appear. The shot will be razor sharp, but failing to have patience will result in a blurry shot. Pumping your shot's af to get the box to appear is my way of guaranteeing focus.
arbitrage wrote:
Sounds like the copy of the 200-600 I used to have. Even though some of my 600 f/6.3 shots looked nice and sharp, most of the time if I shot at f/7.1 it made a crazy difference.
I know other copies of the 200-600 were better than mine at 600 f/6.3 and I bet there is similar variation with the 400-800 at 800 wide open.
I certainly wouldn't expect anything on par with the 600PF which is a super sharp lens even wide open. I even wonder if a 600PF shot cropped to 800mm FOV would look better most of the time than a Sony 400-800 shot at 800??...Show more →
Yeah I noticed the same thing with my 200-600. I was never happy with that lens. It didn’t work at all with filters. I couldn’t even get it sharp in manual focus on a tripod with a filter on and even without a filter the AF was hit or miss.
My 400-800 is so much better in every single way. Tack sharp wide open and focuses perfectly every time even with a clear filter.
I think both lenses have a lot of copy variation and if you get a good copy they are great and if you don’t they aren’t.
I moved from the 600 PF to the 400-800 and I do not have issues with sharpness at f8. It would be scary if it got sharper at f9, but I haven't seen that. I guess I need to test.
Soooo many variables! Atmospheric compression and dampness and temp variances are in their prime right now Spring weather at least around my area.
200mm more of compression, magnification of movement etc can and will contribute. Did you shoot at 600 (580 is where you get the f/stop break and check results? Were you shooting over water? Over damp grass?
Curious as I have the same package you do right now and I’m thrilled but I do get some softer shots by occasion but have not related it to f/8 vs f/9. What focus point settings, did you have bird eye AF on or Animal? Had you shot any other long lenses on the Sony A1 before? What firmware version currently?
What you learned shooting at 600 should be helpful with what happens at 800.
p.1 #11 · Sony 400-800 Poor AF accuracy at 800 f/8
I've had the same issue with my 400-800. At 800mm It RARELY focuses properly. I've tested this indoors on a model bird and the AF-C is very inconsistent. Putting it to AF-S solves this issue. I'm sending it in for warranty.
p.1 #12 · Sony 400-800 Poor AF accuracy at 800 f/8
Logan Nolag wrote:
Yeah I noticed the same thing with my 200-600. I was never happy with that lens. It didn’t work at all with filters. I couldn’t even get it sharp in manual focus on a tripod with a filter on and even without a filter the AF was hit or miss.
My 400-800 is so much better in every single way. Tack sharp wide open and focuses perfectly every time even with a clear filter.
I think both lenses have a lot of copy variation and if you get a good copy they are great and if you don’t they aren’t.
p.1 #13 · Sony 400-800 Poor AF accuracy at 800 f/8
I used filters on Canon and Nikon big teles lenses for many years. They have a holder for small filters of various types including a slot with a dial for the polarizer. The cheap lenses like 200-600 and 400-800 don't have it. If you want to use a front filter they are expensive and need to be very flat. 95mm is not as bad as 112 for the Sigma 120-300.
p.1 #14 · Sony 400-800 Poor AF accuracy at 800 f/8
Sorry to take so long to get back. I posted this on my way out in the field for day 2 of my inaugural trip with the 400-800 and then went to a work conference after that. Here's an example of what I'm talking about. As much as I could the same shot, from a car blind. Lens was as stable as is possible outside of putting it on a tripod. You can see in the f/8 shot it back focuses (the grass behind the bird is in focus), while in the f9 show the bird is in focus.
Here's a link to my iCloud Drive to download the full res jpegs (no edits, just exported from Lightroom)
p.1 #15 · Sony 400-800 Poor AF accuracy at 800 f/8
Definitely a lot of variables! I have experience shooting at 800 on canon with the 800 f/11 and the 200-800. My 200-800 was substantially better at f/9 than my 400-800 at f/8 which I was not expecting given all the reviews I’ve read. At f/9 the Sony is better. Is a shame, but if I have to keep it at f/9 it is what it is. It just becomes annoying to dial the aperture back at 400, but so far I’ve just kept it at f/9 because in the field I don’t want to have to think about it when something happens fast.
Karl Witt wrote:
Soooo many variables! Atmospheric compression and dampness and temp variances are in their prime right now Spring weather at least around my area.
200mm more of compression, magnification of movement etc can and will contribute. Did you shoot at 600 (580 is where you get the f/stop break and check results? Were you shooting over water? Over damp grass?
Curious as I have the same package you do right now and I’m thrilled but I do get some softer shots by occasion but have not related it to f/8 vs f/9. What focus point settings, did you have bird eye AF on or Animal? Had you shot any other long lenses on the Sony A1 before? What firmware version currently?
What you learned shooting at 600 should be helpful with what happens at 800.
p.1 #16 · Sony 400-800 Poor AF accuracy at 800 f/8
Yeah talking to you is what convinced me to get the 400-800 over the 200-600. Unfortunately it seems my copy is less than ideal, but that happens! I may rent another one to test against it and if the rental is clearly better, may reach out it Sony. I have my doubts about whether they’d actually do anything.
billsnature wrote:
I moved from the 600 PF to the 400-800 and I do not have issues with sharpness at f8. It would be scary if it got sharper at f9, but I haven't seen that. I guess I need to test.
p.1 #17 · Sony 400-800 Poor AF accuracy at 800 f/8
Some reviews I’ve read/watched like Steve Perry’s compare the 400-800 quite well at 800 vs the Nikon 800 6.3 so I was expecting it to be in the ballpark of my 600 cropped to 800. At f/9 I think it is.
arbitrage wrote:
Sounds like the copy of the 200-600 I used to have. Even though some of my 600 f/6.3 shots looked nice and sharp, most of the time if I shot at f/7.1 it made a crazy difference.
I know other copies of the 200-600 were better than mine at 600 f/6.3 and I bet there is similar variation with the 400-800 at 800 wide open.
I certainly wouldn't expect anything on par with the 600PF which is a super sharp lens even wide open. I even wonder if a 600PF shot cropped to 800mm FOV would look better most of the time than a Sony 400-800 shot at 800??...Show more →
p.1 #18 · Sony 400-800 Poor AF accuracy at 800 f/8
If you look at the MTF for the two lenses you can see what is going on.
The 400-800 has substantial divergence between the sagittal and tangential (meridional) performance and that starts at quite a low radius. The Nikkor has a fine flat curve as you would expect from a high-grade lens. So if you are a bullseye type of user then maybe the 400-800 is considered plenty adequate, but deteriorates with increasing radius.
p.1 #19 · Sony 400-800 Poor AF accuracy at 800 f/8
icantbebigwill wrote:
Yeah talking to you is what convinced me to get the 400-800 over the 200-600. Unfortunately it seems my copy is less than ideal, but that happens! I may rent another one to test against it and if the rental is clearly better, may reach out it Sony. I have my doubts about whether they’d actually do anything.
You may want to try this test again outside of the car. Shooting from a car especially when there is a temperature difference is between the inside car and outside temp is notorious for giving variable and non-reproducible results. You may indeed have a bad copy, but I would test again on a tripod on a day that has low potential for heat distortion before I sent it in for repair or sold it.
p.1 #20 · Sony 400-800 Poor AF accuracy at 800 f/8
icantbebigwill wrote:
Sorry to take so long to get back. I posted this on my way out in the field for day 2 of my inaugural trip with the 400-800 and then went to a work conference after that. Here's an example of what I'm talking about. As much as I could the same shot, from a car blind. Lens was as stable as is possible outside of putting it on a tripod. You can see in the f/8 shot it back focuses (the grass behind the bird is in focus), while in the f9 show the bird is in focus.
Here's a link to my iCloud Drive to download the full res jpegs (no edits, just exported from Lightroom)
Can you drop the RAW files in that folder ? The f9 seems to be better exposed than the f8 version - or the light changed outside - but there is no metadata to see what the settings are.
