Second Thoughts on Using a Teleconverter: More than twenty years ago I tried using a Canon 1.4x teleconverter on the Canon 500mm L lens and the sharpness results were not good enough...

John Gerlach Loc: Island Park, Idaho

More than twenty years ago I tried using a Canon 1.4x teleconverter on the Canon 500mm L lens and the sharpness results were not good enough for me, so I stopped trying to use teleconverters for many years. In the past couple of months I decided to try the RF 1.4x teleconverter on the Canon 100-500mm lens and figured I would find the same loss of sharpness and drop it. So, while leading a photo workshop at Laguna Seca Ranch in South Texas, I spent one entire morning shooting several thousand images using the 1.4x teleconverter on the 100-500mm while using my best technique on a Wimberley gimbal head inside the photo hide. When I looked at the results with some dread about how they might not be what I was hoping for, I was surprised to see how sharp the images were. Clearly the 1.4x teleconverter did not reduce sharpness much at all and the results were acceptable to me and the folks who publish my images to go along with my articles. I still have not tried the 2x teleconverter on my Canon RF lenses, but I hope to do so this summer.

I suspect that the sharpness would have been good enough all along if only I had AF microadjusted my older Canon lenses with the 1.4x teleconverter on that era. I know when I was AF microadjusting camera/lens combinations, I nearly always found some adjustment was beneficial and was also surprised the few times I did AF microadjust the lens with a teleconverter on it how thing changes. It was not unusual to find a lens by itself my autofocus better with say a +4 AF microadjustment, and when you put at 1.4x teleconverter in the optical path, that adjustment would change, and sometimes by quite a bit such as -3 when the lens by itself was a +4. Now that I have mirrorless Canon R5, the autofocus is much more precise and I am getting suitable photos with or without the 1.4x teleconverter. I think the loss of some sharpness was more the fault of the camera not hitting sharp focus rather than the glass causing it. I should have listened to the reviews of the RF teleconverters sooner as nearly all are glowing reports and I agree with them. Anyway, after carefully looking at thousands of bird images shot with the 100-500mm and the RF 1.4x teleconverter, I give the combination a "two thumbs up." Here are more examples of recent images shot with the RF 1.4x teleconverter on the Canon R5.

burrowing owl
burrowing owl...

(Download)

burrowing owl
burrowing owl...

(Download)

anhinga
anhinga...

(Download)

burrowing owl
burrowing owl...

(Download)

snowy egret
snowy egret...

(Download)

burrowing owls
burrowing owls...

(Download)

Attached file:
(Download)

roseate spoonbill
roseate spoonbill...

(Download)

green heron
green heron...

(Download)

UTMike Loc: South Jordan, UT

Your usual usual excellent work, John! Thanks for sharing.

Elias Amador

Super photos. Love the green heron about to enjoy dinner!

Architect1776 Loc: In my mind

John Gerlach wrote:

More than twenty years ago I tried using a Canon 1.4x teleconverter on the Canon 500mm L lens and the sharpness results were not good enough for me, so I stopped trying to use teleconverters for many years. In the past couple of months I decided to try the RF 1.4x teleconverter on the Canon 100-500mm lens and figured I would find the same loss of sharpness and drop it. So, while leading a photo workshop at Laguna Seca Ranch in South Texas, I spent one entire morning shooting several thousand images using the 1.4x teleconverter on the 100-500mm while using my best technique on a Wimberley gimbal head inside the photo hide. When I looked at the results with some dread about how they might not be what I was hoping for, I was surprised to see how sharp the images were. Clearly the 1.4x teleconverter did not reduce sharpness much at all and the results were acceptable to me and the folks who publish my images to go along with my articles. I still have not tried the 2x teleconverter on my Canon RF lenses, but I hope to do so this summer.

I suspect that the sharpness would have been good enough all along if only I had AF microadjusted my older Canon lenses with the 1.4x teleconverter on that era. I know when I was AF microadjusting camera/lens combinations, I nearly always found some adjustment was beneficial and was also surprised the few times I did AF microadjust the lens with a teleconverter on it how thing changes. It was not unusual to find a lens by itself my autofocus better with say a +4 AF microadjustment, and when you put at 1.4x teleconverter in the optical path, that adjustment would change, and sometimes by quite a bit such as -3 when the lens by itself was a +4. Now that I have mirrorless Canon R5, the autofocus is much more precise and I am getting suitable photos with or without the 1.4x teleconverter. I think the loss of some sharpness was more the fault of the camera not hitting sharp focus rather than the glass causing it. I should have listened to the reviews of the RF teleconverters sooner as nearly all are glowing reports and I agree with them. Anyway, after carefully looking at thousands of bird images shot with the 100-500mm and the RF 1.4x teleconverter, I give the combination a "two thumbs up." Here are more examples of recent images shot with the RF 1.4x teleconverter on the Canon R5.

More than twenty years ago I tried using a Canon 1... (show quote)

I have found that the EF 2X III matched to the EF 100-400MM MII doesn't degrade the photo that I can see. So the RF 2X Should be at least as good .

PHRubin Loc: Nashville TN USA

I wonder if the difference is the focus system. If in the past you used a SLR, the focus plane might have been slightly different than the film plane, which as you mentioned, would require a focus calibration. With the mirrorless, the same sensor that makes the image is used for focusing, so the planes must be the same. For critical focusing with my DSLR I used to use Live View to accomplish the same thing.

Gourmand Loc: Dallas

Like you, I have resisted doublers for decades - but time and quality have marched on. Since Nikon's Z TC-1.4x converter is almost impossible to find, I took a deep breath and tried out the Z TC-2.0x as follows: Nikkor Z 600mm f/4 TC with internal 1.4 inserted (bringing it up to 840mm) and added the TC-2.0x for a 1680mm, mounted on a Z9 set to 1/2000 sec at f/11, ISO 2200 and the entire rig steadied on a unipod. The detail in the feathers stunned me (I think the baby egret was two counties away at the time). The quality is not unique to the series of images shot that day.

John Gerlach Loc: Island Park, Idaho

PHRubin wrote:

I wonder if the difference is the focus system. If in the past you used a SLR, the focus plane might have been slightly different than the film plane, which as you mentioned, would require a focus calibration. With the mirrorless, the same sensor that makes the image is used for focusing, so the planes must be the same. For critical focusing with my DSLR I used to use Live View to accomplish the same thing.

Yes, I think having the DSLR misfocus was more the problem for unsharp images and not the extra glass so much. Now that autofocus is vastly superior with mirrorless cameras, we are all doing better with our focus.

John Gerlach Loc: Island Park, Idaho

Gourmand wrote:

Like you, I have resisted doublers for decades - b... (show quote)

Nice feather detail. Clearly, the images shot with teleconverters on mirrorless cameras are of better quality in terms of sharpness.

Architect1776 Loc: In my mind

John Gerlach wrote:

Yes, I think having the DSLR misfocus was more the problem for unsharp images and not the extra glass so much. Now that autofocus is vastly superior with mirrorless cameras, we are all doing better with our focus.

Also have found that DSLRS struggled to AF at all.
Now with mirrorless there is no problem at all and is faster than I can respond.

Gourmand Loc: Dallas

Thanks John, as a post script: I let the Z9 do the tracking and focusing on the eye. Having concentrated on landscapes for years, Nature photography has become my current passion due to all the enhancements available with the mirrorless system - it is so much faster and more accurate than I ever dreamed of being (but always wanted to be).

User ID

PHRubin wrote:

I wonder if the difference is the focus system. If in the past you used a SLR, the focus plane might have been slightly different than the film plane, which as you mentioned, would require a focus calibration. With the mirrorless, the same sensor that makes the image is used for focusing, so the planes must be the same. For critical focusing with my DSLR I used to use Live View to accomplish the same thing.

Exactly. A focal magnifier magnifies all errors. SLRs are just more error prone than EVFs. This is not new news.

mundy-F2 Loc: Chicago suburban area

John Gerlach wrote:

More than twenty years ago I tried using a Canon 1.4x teleconverter on the Canon 500mm L lens and the sharpness results were not good enough for me, so I stopped trying to use teleconverters for many years. In the past couple of months I decided to try the RF 1.4x teleconverter on the Canon 100-500mm lens and figured I would find the same loss of sharpness and drop it. So, while leading a photo workshop at Laguna Seca Ranch in South Texas, I spent one entire morning shooting several thousand images using the 1.4x teleconverter on the 100-500mm while using my best technique on a Wimberley gimbal head inside the photo hide. When I looked at the results with some dread about how they might not be what I was hoping for, I was surprised to see how sharp the images were. Clearly the 1.4x teleconverter did not reduce sharpness much at all and the results were acceptable to me and the folks who publish my images to go along with my articles. I still have not tried the 2x teleconverter on my Canon RF lenses, but I hope to do so this summer.

I suspect that the sharpness would have been good enough all along if only I had AF microadjusted my older Canon lenses with the 1.4x teleconverter on that era. I know when I was AF microadjusting camera/lens combinations, I nearly always found some adjustment was beneficial and was also surprised the few times I did AF microadjust the lens with a teleconverter on it how thing changes. It was not unusual to find a lens by itself my autofocus better with say a +4 AF microadjustment, and when you put at 1.4x teleconverter in the optical path, that adjustment would change, and sometimes by quite a bit such as -3 when the lens by itself was a +4. Now that I have mirrorless Canon R5, the autofocus is much more precise and I am getting suitable photos with or without the 1.4x teleconverter. I think the loss of some sharpness was more the fault of the camera not hitting sharp focus rather than the glass causing it. I should have listened to the reviews of the RF teleconverters sooner as nearly all are glowing reports and I agree with them. Anyway, after carefully looking at thousands of bird images shot with the 100-500mm and the RF 1.4x teleconverter, I give the combination a "two thumbs up." Here are more examples of recent images shot with the RF 1.4x teleconverter on the Canon R5.

More than twenty years ago I tried using a Canon 1... (show quote)

Very nice images. Love the owls. I am considering a teleconverter for a 70-200 zoom.
Thanks.
Mundy

J-SPEIGHT Loc: Akron, Ohio

John Gerlach wrote:

More than twenty years ago I tried using a Canon 1.4x teleconverter on the Canon 500mm L lens and the sharpness results were not good enough for me, so I stopped trying to use teleconverters for many years. In the past couple of months I decided to try the RF 1.4x teleconverter on the Canon 100-500mm lens and figured I would find the same loss of sharpness and drop it. So, while leading a photo workshop at Laguna Seca Ranch in South Texas, I spent one entire morning shooting several thousand images using the 1.4x teleconverter on the 100-500mm while using my best technique on a Wimberley gimbal head inside the photo hide. When I looked at the results with some dread about how they might not be what I was hoping for, I was surprised to see how sharp the images were. Clearly the 1.4x teleconverter did not reduce sharpness much at all and the results were acceptable to me and the folks who publish my images to go along with my articles. I still have not tried the 2x teleconverter on my Canon RF lenses, but I hope to do so this summer.

I suspect that the sharpness would have been good enough all along if only I had AF microadjusted my older Canon lenses with the 1.4x teleconverter on that era. I know when I was AF microadjusting camera/lens combinations, I nearly always found some adjustment was beneficial and was also surprised the few times I did AF microadjust the lens with a teleconverter on it how thing changes. It was not unusual to find a lens by itself my autofocus better with say a +4 AF microadjustment, and when you put at 1.4x teleconverter in the optical path, that adjustment would change, and sometimes by quite a bit such as -3 when the lens by itself was a +4. Now that I have mirrorless Canon R5, the autofocus is much more precise and I am getting suitable photos with or without the 1.4x teleconverter. I think the loss of some sharpness was more the fault of the camera not hitting sharp focus rather than the glass causing it. I should have listened to the reviews of the RF teleconverters sooner as nearly all are glowing reports and I agree with them. Anyway, after carefully looking at thousands of bird images shot with the 100-500mm and the RF 1.4x teleconverter, I give the combination a "two thumbs up." Here are more examples of recent images shot with the RF 1.4x teleconverter on the Canon R5.

More than twenty years ago I tried using a Canon 1... (show quote)

Outstanding images John.

Manglesphoto Loc: 70 miles south of St.Louis

John Gerlach wrote:

More than twenty years ago I tried using a Canon 1.4x teleconverter on the Canon 500mm L lens and the sharpness results were not good enough for me, so I stopped trying to use teleconverters for many years. In the past couple of months I decided to try the RF 1.4x teleconverter on the Canon 100-500mm lens and figured I would find the same loss of sharpness and drop it. So, while leading a photo workshop at Laguna Seca Ranch in South Texas, I spent one entire morning shooting several thousand images using the 1.4x teleconverter on the 100-500mm while using my best technique on a Wimberley gimbal head inside the photo hide. When I looked at the results with some dread about how they might not be what I was hoping for, I was surprised to see how sharp the images were. Clearly the 1.4x teleconverter did not reduce sharpness much at all and the results were acceptable to me and the folks who publish my images to go along with my articles. I still have not tried the 2x teleconverter on my Canon RF lenses, but I hope to do so this summer.

I suspect that the sharpness would have been good enough all along if only I had AF microadjusted my older Canon lenses with the 1.4x teleconverter on that era. I know when I was AF microadjusting camera/lens combinations, I nearly always found some adjustment was beneficial and was also surprised the few times I did AF microadjust the lens with a teleconverter on it how thing changes. It was not unusual to find a lens by itself my autofocus better with say a +4 AF microadjustment, and when you put at 1.4x teleconverter in the optical path, that adjustment would change, and sometimes by quite a bit such as -3 when the lens by itself was a +4. Now that I have mirrorless Canon R5, the autofocus is much more precise and I am getting suitable photos with or without the 1.4x teleconverter. I think the loss of some sharpness was more the fault of the camera not hitting sharp focus rather than the glass causing it. I should have listened to the reviews of the RF teleconverters sooner as nearly all are glowing reports and I agree with them. Anyway, after carefully looking at thousands of bird images shot with the 100-500mm and the RF 1.4x teleconverter, I give the combination a "two thumbs up." Here are more examples of recent images shot with the RF 1.4x teleconverter on the Canon R5.

More than twenty years ago I tried using a Canon 1... (show quote)

imagemeister Loc: mid east Florida

John Gerlach wrote:

More than twenty years ago I tried using a Canon 1.4x teleconverter on the Canon 500mm L lens and the sharpness results were not good enough for me,

Nice shots of great subjects ! - but, IMHO they are all on the soft side.......tho I have shot the Canon 2X II on the original EF 300 2.8 and the 1.4X II on the EF 400 5.6 with very satisfactory results - so I am not necessarily down on TC's ! ......Having used Sony's Clear Image Zoom, today, I lean towards cropping and applying pixel enlargement software over using an optical TC.

Here is my test of the Sony RX10 with 2X CIZ - https://www.uglyhedgehog.com/t-749907-1.html
.