Tele-converter or DX mode

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bobellisjr said:
Yes! Z8 using the Z180-600mm lens
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I just posted my tests with Z8 and Z 180-600 on its own with cropping and with 1.4x tc and 2x tc:

Z 180-600 Teleconverter Test

BACKGROUND I started in Nikon Z system with a Z8 and Z 70-200 f2.8. Soon after got a used Z 2x to get to 400mm (a setup that works well). Eventually got Z 180-600 f5.6-6.3. Recently purchased used Z 1.4x to get closer to distant coyote pups with the longer lens. Photos and results follow, but...
bcgforums.com bcgforums.com
 
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apakett said:
Several reviewers make that claim, a TC gives sharper rests than cropping. What is missing is an actual comparison. It will make a difference between what lens you are comparing and the camera resolution. Fast high end lenses can take advantage of a TC. High resolution cameras do well when cropped.

I would like to see a link to an actual comparison.
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See above for link to my test.
 
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Roy said:
tests seem to show that a TC is sharper than a DX crop.
the only real drawback is losing 1-2 stops of light 🦘
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With F mount equipment I found the first part of your opinion to be reasonably true using my own equipment.
The however I find is that often less efficient auto focus, usually a slower shutter speed, less DOF compared to no TC or DX et cetera make it more difficult to get a first class image using TC's without resorting to a good tripod
Z lenses and particularly the Z TC's make it easier to obtain distinctly higher resolution than with the F generation - making either option more viable when a longer focal length is not available.
 
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While using a TC means a loss of light and a higher aperture, DX cropping carries a higher level of noise by about 1.2 stops. So it ends up being close to a wash. Compare any recent full frame camera to the same camera in DX mode on www.Photonstophotos.net .

In general, with a fast lens the TC works very well and has no meaningful impact on image quality. You still have the option of cropping later, but the loss of image quality with a given combination may mean you don't want deep cropping. When you are using an f/5.6 or f/6.3 lens and adding a teleconverter, it does not work very well on a DSLR but on a mirrorless camera it still works reasonably well depending on the lens. I found the 200-500 f/5.6 + 1.4 TC would work better on my Z6/Z7ii than on my D850, but it was still not acceptably sharp for much cropping. My 200-400 f/4 + the same 1.4 TC was much better on the Z cameras and provided more ability to crop even after using the TC.
 
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On DSLRs you couldn't pay me to use a TC. I shot the D850 for a short time and mostly the D500 with the 500PF and regularly found much better IQ without the TC in either FX or DX or cropping as much as 100%. On my Z9 with the 500PF the TC was very close in IQ that without. Since I shoot the Z9+800PF now, the light is much more important to me as my style of shooting is wide open, f9 or smaller isn't for me. I would rather a few less pixels to get a sharper image.

Cropping the Z9 images as much as 100% isn't a problem, even for large prints up to 20x30.

Also, cropping and the noise issue people talk about isn't really an issue. I shoot full manual and never auto ISO. Unless I just have to go higher I usually shoot ISO500 since the Z9 is a dual gain sensor and just adjust me shutter speed when I have enough light. This also gets me to my point with noise. Shooting at ISO500 basically builds in shadow recovery. For example, if I shoot ISO2000 and have to say recover 2 stops of shadows, I am exposing 2 stops of ISO so the equivalent of about ISO6400. But if I am shooting at ISO500, those same 2 stops of recovery is about ISO1600. This also exposes much less noise when cropping in.

So for me. a TC is a no no, the loss of light will impact the image far more and in more ways then one for me. Crop or DX for me. Also, I generally only use DX to improve the AF for subjects a little further out as increasing the size of the subject in the EVF helps the AF system
 
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EricKlees said:
On DSLRs you couldn't pay me to use a TC.
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As I mentioned earlier - you did not have to pay me as with care to stabilise the camera and lens I am one of several I know that obtained moderately more image resolution with an F mount TC on a D850 than cropping.
I agree with a Z8/9 and IBIS/Z mount VR it is possible to get usefully more resolution just with cropping than was possible with F mount - and also find with care I can get even more resolution with a Z TC.
To some extent software like Lightroom Denoise can help - as higher ISO's can be used to offset noise at higher ISO's to help keep shutter speeds high when using TC's.
 
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EricKlees said:
On DSLRs you couldn't pay me to use a TC. I shot the D850 for a short time and mostly the D500 with the 500PF and regularly found much better IQ without the TC in either FX or DX or cropping as much as 100%. On my Z9 with the 500PF the TC was very close in IQ that without. Since I shoot the Z9+800PF now, the light is much more important to me as my style of shooting is wide open, f9 or smaller isn't for me. I would rather a few less pixels to get a sharper image.

Cropping the Z9 images as much as 100% isn't a problem, even for large prints up to 20x30.

Also, cropping and the noise issue people talk about isn't really an issue. I shoot full manual and never auto ISO. Unless I just have to go higher I usually shoot ISO500 since the Z9 is a dual gain sensor and just adjust me shutter speed when I have enough light. This also gets me to my point with noise. Shooting at ISO500 basically builds in shadow recovery. For example, if I shoot ISO2000 and have to say recover 2 stops of shadows, I am exposing 2 stops of ISO so the equivalent of about ISO6400. But if I am shooting at ISO500, those same 2 stops of recovery is about ISO1600. This also exposes much less noise when cropping in.

So for me. a TC is a no no, the loss of light will impact the image far more and in more ways then one for me. Crop or DX for me. Also, I generally only use DX to improve the AF for subjects a little further out as increasing the size of the subject in the EVF helps the AF system
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You’re throwing bombshells here. And I love reading it. I’m still trying to grasp the concept of shooting ISO 500 instead of ISO 2000.
What’s the formula of the calculation?

Regarding TC’s…
Is it because f/6.3 is as high as your like, or is it a TC in general?
In other words; With a faster lens like the 400/4.5, would you still DX instead of using a 1.4TC?

All those presented photos with the 600pf + 1.4 TC, according to your knowledge they would get a better IQ and cleaner results just DX’ing?
 
BillW said:
I've always found that a bit confusing, since you can view a photo with pixels at 1:1 even if you have not cropped it. It seems to speak more to how you view the photo than how you crop it.
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I agree. It's something people say, and I usually can figure out what they mean when they say it. Kind of like the word literally.
 
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I use a Canon R7 with a Canon 100-400 mk 2 zoom and either a Sigma 1.4 or Sigma 2x converter. The combo works good enough for me and I guess the image stabilization is combined body and lens.

Scally 11 06 24-5813-DeNoiseAI-standard resize.jpg
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Combo with 1.4 converter.

Peace Park 21 03 24-4848 resize.jpg
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Combo with 2x converter.

Peace Park duck 2x converter crop-2.JPG
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Cropped a lot.

These two photos were handheld.
 
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I'm not into Nikon, Canon, Sony, Fuji etc. wars. All are excellent tools that are much better at photographing things than me. I would be interested in seeing photos taken with a full frame and cropped. [ Canon R5 or Nikon whatever, or Sony or Fuji or Phase 1, or even James Webb clone if anyone has one ]
One benefit I get from using my present set up is that minimum distance of focus is not affected by the extender. Helps a lot when getting close to visiting birds on the deck of the granny flat.
 
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Len Shepherd said:
As I mentioned earlier - you did not have to pay me as with care to stabilise the camera and lens I am one of several I know that obtained moderately more image resolution with an F mount TC on a D850 than cropping.
I agree with a Z8/9 and IBIS/Z mount VR it is possible to get usefully more resolution just with cropping than was possible with F mount - and also find with care I can get even more resolution with a Z TC.
To some extent software like Lightroom Denoise can help - as higher ISO's can be used to offset noise at higher ISO's to help keep shutter speeds high when using TC's.
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Well you're one of the few as i know dozens of people who feel the same way, that IQ suffered far too much compared to cropping and no loss of light resulting in higher ISO's. But it's always what you feel works best for you.
 
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bleirer said:
This was a good recent video, hope I didn't repeat:

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I find your utter disregard for the feelings of the people that gave us hope that by using a switch on the camera body we could get something we can never have an insult to the brave men and women of constructive marketing. I take it you believe that these wonderful people, that only want to provide photographers with hope against common sense, are doing it for ulterior motives. Shame on you!

Anyway enough of that. I am presently looking for second hand Canon extension tubes. I do have some 'el cheapo' ones but they are a bit of a worry; also they do not allow stacking of extenders as they strengthen the structure of them by not making the hole in the middle round. If I ever get a suitable extension tube I will place it between the two extenders I have and see what results I get.
 
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I usually end up doing both, TC's + cropping.

I think often times it's pretty close to a wash. As others have said, cropping increases noise similar to decreasing aperture (say going from f2.8 to f4, losing 1 stop of light - compared to a moderate crop which is 1.3 stops worse in terms of noise, or a heavy crop which is 2-3 stops worse). However, adding a TC also degrades IQ on its own - which is essentially another penalty on top of the strictly ISO pain.

In theory, the best practice would be to crop first, then use TC's - as it would allow you to retain more DOF/"bokeh", as well as IQ I think. a cropped 400mm f2.8 image shot at f2.8 will have the same background characteristics as a full frame 400mm f2.8 image, whereas when you flick on the TC to 560mm f4, you will now have a different "look".
 
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bleirer said:
Cropping also reduces depth of field.
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do you have any literature or videos on this?

I'm sure you're right, I just can't process "why" in my head.

DOF/Background separation/Bokeh, etc. is something I'm still always very confused about...

Nimi said:
And dynamic range. 🤠
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literature on this as well?

is it purely because it "removes" a lot of the image, and often the corners and outer portions contain a lot of color?
 
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