1.4 extender effect on dof

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McNyat

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Ciaran
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Hi everyone, I havent been on for a while but any enjoying shooting when i get a chance. I have an r6 and an r7, both of which I use to shoot my kids football matches, paired with a 70-200f2.8 Canon. I would really love a 300mm f2.8 to get extra distance but they are so pricey, so thinking about a 1.4 extender. Im aware that this will change my maximum aperture down from f2.8, but am wondering if the extra focal length might help to offset this? Almost always shooting outdoors in daylight so light mostly not a problem. For context, I love the shallower dof on the ff r6 compared to the r7, but the r7 gives extra distance. Any experienced opinions and advice would be greatly appreciated, thanks.
 
Thanks. Yes i understand this ok. I may be wrong but think dof gets shallower with distance.... and wondering if the extra length guven by adding a 1.4 extender would offset the change in apperture?
Please advise folks....
 
Im using the r6 and r7 with converters to fit ef lenses, specifically a canon 70-200 f2.8 mk 1. Would i need the ef or rf extender, and would it be worth going for the mk3 version extender over the mk2? I read somewhere that the mk 3 would only see the full benefits on newer lenses.... is this totally correct?
 
McNyat said:
Im using the r6 and r7 with converters to fit ef lenses, specifically a canon 70-200 f2.8 mk 1. Would i need the ef or rf extender, and would it be worth going for the mk3 version extender over the mk2? I read somewhere that the mk 3 would only see the full benefits on newer lenses.... is this totally correct?
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EF, but totally and utterly pointless with that lens. It just won't resolve properly. Big fat whites may be a different story.
 
McNyat said:
Sorry, but i dont understand???
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neither do I and I have usde a 1.4 on my 70-200 ... unless its the camera 1.4 combination ?
 
LongLensPhotography said:
EF, but totally and utterly pointless with that lens. It just won't resolve properly. Big fat whites may be a different story.
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Can anyone help with this response, as i dont understand it. I would just like to know if the mk2 or 3 would be viable options, if so which one, and why? Any help woukd be greatly appreciated.
 
McNyat said:
Thanks. Yes i understand this ok. I may be wrong but think dof gets shallower with distance.... and wondering if the extra length guven by adding a 1.4 extender would offset the change in apperture?
Please advise folks....
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DOF does not get shallower with distance.
Adding a 1.4x does not (necessarily) increase the length.
Use the online DOF calculators.
 
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What is being suggested is that particular lens suffers IQ wise and possibly in relation to AF speed when used with a 1.4x converter.

However, that said, please see the response from Demilion above

Mike
 
McNyat said:
Can anyone help with this response, as i dont understand it. I would just like to know if the mk2 or 3 would be viable options, if so which one, and why? Any help woukd be greatly appreciated.
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Lens snobbery.
 
ecoleman said:
Ignore him. The 1.4x TC works perfectly well with the 70-200 f2.8.
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Thank you. I really need the extra reach but cant justify the expense of the 300mm. Plus I feel conscious enough with the 70-200mm without lugging a massive lens about. Ive read that the af speed and quality are reduced when using the 1.4 extender, but if i thought that this drop wasnt going to be massively noticed I would be really tempted to try it? Have also read that there is minimal difference between the mk 1, 2 and 3. Do you have any advice on this as well? Thanks
 
McNyat said:
Thank you. I really need the extra reach but cant justify the expense of the 300mm. Plus I feel conscious enough with the 70-200mm without lugging a massive lens about. Ive read that the af speed and quality are reduced when using the 1.4 extender, but if i thought that this drop wasnt going to be massively noticed I would be really tempted to try it? Have also read that there is minimal difference between the mk 1, 2 and 3. Do you have any advice on this as well? Thanks
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Your autofocus will be a tad slower but still perfectly useable. IQ will also be reduced but the 70-20. Is a superb lens so again the reduction in quality is negligible.

If I remember correctly I had the 1.4. V2 and was quite happy with the results. Never felt the need to upgrade.

I’ve moved on all Rf lenses now so no longer have the 70-200 or the 1.4TC in EF variety.
 
One thing I would add thats to your advantage.. used extenders dont really lose money so if you bought one for 200 quid and didnt like it you could probably sell for 200 quid so no harm done :) buying used is the way to go you wont lose out then . better still if you ahve a local contact who could loan you one ?
 
ecoleman said:
Your autofocus will be a tad slower but still perfectly useable. IQ will also be reduced but the 70-20. Is a superb lens so again the reduction in quality is negligible.

If I remember correctly I had the 1.4. V2 and was quite happy with the results. Never felt the need to upgrade.

I’ve moved on all Rf lenses now so no longer have the 70-200 or the 1.4TC in EF variety.
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Great, thank you. Think ill give it a go
 
This might help, or not ! . . . I have the Mkiii 1.4x : The leaves in the orange box of the fir tree are what I looked at to compare sharpness. All photos in this comparison were taken within seconds of each other.

The leaf order is 300mm f2.8 - 420mm f4 - 300mm f8 - 420mm f8 (The 420mm's are with the Mkiii1.4x).
The 300mm photos were enlarged to match the 420mm ones. Can you see a difference?

From my comparison below, is there a need for a teleconverter or is cropping in just as good? (the lens is the 300mm f2.8 IS USM ii),

Sharpness 300 and 300+1.4x _ 300mm f2.8 - 420mm f4 - 300mm f8 - 420mm f8 by Stephen_Photographs02, on Flickr
 
Cropping in loses MP so reduces the potential maximum print size. If you don't intend to print big (A3+), cropping is a decent option.
 
Nod said:
Cropping in loses MP so reduces the potential maximum print size. If you don't intend to print big (A3+), cropping is a decent option.
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As its stands atm, I am currently cropping in fairly heavily on players when they are a distance away, which is obviously resulting in loss of quality (compared to the other pics when players are closer). Thats what is
making me want the extra length, as I cant help but think that any slight loss of quality would still be better than very heavy cropping?
 
McNyat said:
As its stands atm, I am currently cropping in fairly heavily on players when they are a distance away, which is obviously resulting in loss of quality (compared to the other pics when players are closer). Thats what is
making me want the extra length, as I cant help but think that any slight loss of quality would still be better than very heavy cropping?
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Hi . . . you asked "any slight loss of quality would still be better than very heavy cropping?" . . . in my example above (on downloading and having a look at the original file size which you are welcome to do) the second leaf starting from the very left looks the best - this is WITH the 1.4xiii on the 300 2.8 IS ii. The 420mm f4.0 'combination' beats the 300mm f2.8 enlarged a bit. Other photos may vary but it is a close call either way. I say there is no loss of quality with the 1.4xiii on my 300 2.8 ii : NOTE - the 1.4xiii is a magnifying glass lens that will magnify and accentuate any lens issues - the 300mm 2.8 ii is an exceptionally good lens.
 
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Nod said:
Cropping in loses MP so reduces the potential maximum print size. If you don't intend to print big (A3+), cropping is a decent option.
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It really doesn't reduce maximum print size... at least not necessarily so. Maximum print size is really based upon recorded detail/resolution, and *not* megapixels/PPI. I.e. I have 46MP images that wouldn't print well above A4; and I have others that would print well at A0.
 
McNyat said:
Thanks. Yes i understand this ok. I may be wrong but think dof gets shallower with distance.... and wondering if the extra length guven by adding a 1.4 extender would offset the change in apperture?
Please advise folks....
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Any increase in the final magnification will result in less DOF; this includes:
Using a TC
Using a longer FL
Using a shorter subject distance
Using a crop sensor
Cropping in post
Viewing the output image from a shorter distance

And the opposite is also true. However, "DOF" doesn't really say anything about how the BG/OOF regions will render. I.e. if you use a longer FL and back up to maintian the same subject size the DOF will be ~ the *same; but the images could be VERY different.

(*assuming both are beyond/short of their respective HFD)
 
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Fixer said:
I say there is no loss of quality with the 1.4xiii on my 300 2.8 ii : NOTE - the 1.4xiii is a magnifying glass lens that will magnify and accentuate any lens issues - the 300mm 2.8 ii is an exceptionally good lens.
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This is really a system question/equation...

Adding a TC necessarily reduces lens resolution; it is impossible for it to not. If a lens is capable of resolving 100 L/mm, it is only resolving a maximum of 100 L/1.4mm with a 1.4x TC added (72L/mm). And that's only if the TC doesn't add any aberrations of its own.

However, if the lens was far out-resolving the sensor originally, then the loss may not be recorded. Or if situation/technique was limiting lens resolution more than the TC does, it may not be recorded. And if the TC adds few aberrations, then the increased sensor resolution/image area may result in a (nominal) increase in recorded resolution... it's really very situational.

IMO, one advantage using a TC usually has is that it tends to cause the user to use settings more appropriate for the increased magnification... i.e. SS ≥ effective FL.
 
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I am going to say.. for the most part.. I am lost now :) Hope the OP isn't a novice or he will have got lost way before I did :)
 
Have made the decision to go for it... with mk2 and mk3 versions available used on mpb. Is the mk3 worth the extra cash?
 
McNyat said:
Have made the decision to go for it... with mk2 and mk3 versions available used on mpb. Is the mk3 worth the extra cash?
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Yes . . . all reviews say it, the 1.4xiii is best (it therefore also has a better re-sale value for the future if need be).
 
McNyat said:
Have made the decision to go for it... with mk2 and mk3 versions available used on mpb. Is the mk3 worth the extra cash?
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From what I understand, the primary benefit of the MkIII is that when combined with some of the MKII supertele's it allows certain bodies to retain f/8 and cross type autofocus for all focus points. IMO, this must be due to a higher total/combined IQ for those combinations.
 
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