Canon RF 14mm F/1.4 – Is it the Astrophography Dream Lens for RF?

[Richard-CN]

It's been over a week since Canon announced the Canon RF 14mm f/1.4, and much has been read, said, and debated over this relatively expensive lens. I originally was going to do that as a summary of the reviews, and about halfway through the article, I had done enough of a divergence that I changed […]

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[benperrin]

One thing about these calculators that people seem to miss is that resolution plays a part. It really does seem like 8 seconds is a good exposure time without a star tracker. PetaPixel was really defensive when people called them out in the comments.

However one feature I'd really like Canon to implement is an infinity focus recall/set button. Hasselblad seems to have that feature where you press infinity and it focuses for you. If anyone knows how to do that on a Canon I'd love to know. It would save some time.

 

[neuroanatomist]

There were other aspects as well, lens profile (they used the RF 16mm profile), focusing, etc., on that image that I won’t get into. The workflow and exposure settings were not optimal decisions, so it seems odd to conclude it was a problematic lens.

I had thought PetaPixel was reasonably reputable. The wrong profile, and one for a relatively cheap, 2-stop slower non-L lens. He also applied additional manual distortion correction, which is linear and barrel only, while a proper profile corrects for the nonlinear nature of most distortion and any mustache components. The only conclusion I draw from that review is that I will no longer consider PetaPixel as a trustworthy source of information. Personally, I would not repost images from the review...it's not as egregious as some other misinformation that has been spread around over the past several years but better to be part of the solution than part of the problem, IMO.

 

[neuroanatomist]

However one feature I'd really like Canon to implement is an infinity focus recall/set button. Hasselblad seems to have that feature where you press infinity and it focuses for you. If anyone knows how to do that on a Canon I'd love to know. It would save some time.

Most lenses can focus beyond infinity (insert Buzz Lightyear motto here, if you like), because the position of the focusing group(s) for infinity focus varies based on the temperature of the lens. Does Hasselblad take that into account? Warm night? Cold night? Lens heater? For astrophotography, I would not rely on a preprogrammed infinity focus.

 

[Richard-CN]

One thing about these calculators that people seem to miss is that resolution plays a part. It really does seem like 8 seconds is a good exposure time without a star tracker. PetaPixel was really defensive when people called them out in the comments.

Our calculator takes into account resolution (or more accurately, the pixel pitch) as well as the target declination. Writing up the description of that calculator gave me a headache. I think with a 24MP sensor, you could get away with around 14 or so seconds, but if you want to pixel peep with a 45MP sensor, yeah you are looking at around 8 seconds.

I purposely left out peta pixel as the source, but yeah. i'm not sure what was going on with that review.

 

[Richard-CN]

Most lenses can focus beyond infinity (insert Buzz Lightyear motto here, if you like), because the position of the focusing group(s) for infinity focus varies based on the temperature of the lens. Does Hasselblad take that into account? Warm night? Cold night? Lens heater? For astrophotography, I would not rely on a preprogrammed infinity focus.

maybe constrast detect and the smallest point source?

but a hard and/or fixed infinity stop would be problematic for sure.

 

[benperrin]

maybe contrast detect and the smallest point source?

but a hard and/or fixed infinity stop would be problematic for sure.

Yes, something like that would be fantastic. Although I have to say that at least Canon has a good zoom in ratio on the R5 and other bodies. It makes it reasonably quick to get focus in the dark.

 

[mccasi]

Sorry to be that guy, but the Sony 14 1.8 gm is half the price, 2/3 the weight, smaller and famously has (almost) no aberrations wide open on a 60MP sensor… the canon 14mm has to be stopped down to 2.8 to be even remotely where the Sony is… and that’s before you consider the a7cr has 1 stop better noise performance (source:https://www.photonstophotos.net/Charts/RN_e.htm) - which gives it 2.33 stops advantage …

if you do wide angle Milky Way photography normally:
1. set the aperture to acceptable aberrations canon 14 1.4 @ 2.8, Sony 14 1.8 @ 1.8
2. Star tracker MSM nomad or something
3. 15-30 sec sub exposures
4. Stack the foreground and background etc
Then this lens needs somewhere between 2.33 to 3.33 the integration time for the same results!!

Buy this lens if you’re happy to spend EXTRA 13 sub exposures for EVERY 10 sub exposures you would take with the Sony setup.

the comparison is so ridiculous that CR has ignored it from the comparison

… avoid the ad hominem attacks guys. @Canon Rumors I’m disappointed you participate in pure tribalism

 

[alFR]

Sorry to be that guy, but the Sony 14 1.8 gm is half the price, 2/3 the weight, smaller and famously has no aberrations wide open on a 60MP sensor… the canon 14mm has to be stopped down to 2.8 to be even remotely where the Sony is… and that’s before you consider the a7cr has 1 stop better noise performance - which gives it 2.5 stops advantage … the comparison is so ridiculous that CR has ignored it from the comparison

Assuming that’s true (I’m not familiar with the noise data on the Sony, sorry) it would cost me £4000 (approx) to buy that lens/body combo. The Canon lens is £2400. Given I’ve already got Canon kit, even if I was “Astro-curious” and flush with cash so wanting to buy something wider than the Rokinon 2.8 I’d have a hard time justifying buying the Sony.

 

[benperrin]

Sorry to be that guy, but the Sony 14 1.8 gm is half the price, 2/3 the weight, smaller and famously has no aberrations wide open on a 60MP sensor… the canon 14mm has to be stopped down to 2.8 to be even remotely where the Sony is… and that’s before you consider the a7cr has 1 stop better noise performance - which gives it 2.5 stops advantage … the comparison is so ridiculous that CR has ignored it from the comparison

Are you sure that the Sony A7CR is a stop better? and compared to what? I just compared it to the R5 and the R5 looked better to me in every scene at ISO 6400 and both cameras had about the same iso range.

 

[Ian K]

If you want to focus correctly for astro work, you can’t do better than a bahtinov mask. Use the rear screen to zoom in to a bright star and centre it in the screen. Then place the bahtinov mask in front of the lens. Or simply hold it there, if like the RF 14mm there are no threads. Now manually focus until you have a sharp star. You now have perfect focus for Astro, remove the mask.

For example the Kase Night Focus Tool or Kase Bright Star circular filter. I’ve used the Bright star to great effect.

Batinov Masks

 

[benperrin]

If you want to focus correctly for astro work, you can’t do better than a bahtinov mask. Use the rear screen to zoom in to a bright star and centre it in the screen. Then place the bahtinov mask in front of the lens. Or simply hold it there, if like the RF 14mm there are no threads. Now manually focus until you have a sharp star. You now have perfect focus for Astro, remove the mask.

For example the Kase Night Focus Tool or Kase Bright Star circular filter. I’ve used the Bright star to great effect.

Batinov Masks

I looked into masks some time ago but the problem I have is that it makes the process more complicated rather than less. Focus on Stars has an option for 14mm that might work but some sort of adapter would be required.

 

[candyman]

Sorry to be that guy, but the Sony 14 1.8 gm is half the price, 2/3 the weight, smaller and famously has no aberrations wide open on a 60MP sensor… the canon 14mm has to be stopped down to 2.8 to be even remotely where the Sony is… and that’s before you consider the a7cr has 1 stop better noise performance - which gives it 2.5 stops advantage … the comparison is so ridiculous that CR has ignored it from the comparison

On paper that Sony lens does not impress me

https://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=1559&Camera=1538&Sample=0&FLI=0&API=0&LensComp=1762&CameraComp=1697&SampleComp=0&FLIComp=0&APIComp=1

But we have to see the real world tests/examples

 

[David - Sydney]

A good overview.
The Sony/sigma options are substantially cheaper if you already are in that system.
Getting the RF20/1.4 + RF14/1.4 locally would be about the same cost as a A7iii (new) + 14/1.8 + 20/1.8. Or even a second hand A7iv. The Sony stuff gets on sale and available second hand. The RF14 and RF20 won't be discounted or available used (for a long time).

Canon threw everything into a great 14mm but if they asked me (and they didn't), a better astro lens would have been manual focus with dew heater and focus lock as you mentioned. the cost would have been a lot cheaper.

If you can afford or justify its use then it is a great choice but there are only ~10 new moons a year to use it - if the weather cooperates.
Coma isn't everything but it is annoying if substantial. All depends on stitching for corner sharpness.

The alternative is to get good at tracking and use a slower lens for a longer exposure. The Samyang 14/2.8 and lots of trackers would be a cheaper option. Of course, certain foregrounds don't lend themselves to tracking/longer exposures especially trees reaching up in the sky.

 

[Richard-CN]

Sorry to be that guy, but the Sony 14 1.8 gm is half the price, 2/3 the weight, smaller and famously has no aberrations wide open on a 60MP sensor… the canon 14mm has to be stopped down to 2.8 to be even remotely where the Sony is… and that’s before you consider the a7cr has 1 stop better noise performance - which gives it 2.5 stops advantage … the comparison is so ridiculous that CR has ignored it from the comparison

that's cute but what does it have to do with the RF mount? it was literally in the title and I'm not sure you actually read the article. Comparisons were not even a core part of this article.

sorry to be that guy, but no, you re a little wrong on - everything?

Let's see coma.


while, "okay" .. it's certainly not "nothing".

secondly on what planet is 1750 50% of 2600?

third:



I am looking for that miraculous 1EV better high ISO.

and finally.

60MP means if you are concerned about point sharpness (which you mentioned) your light gathering aka exposure time would be shorter. around 8 seconds versus 10 seconds for 5 trailing pixels.

 

[Richard-CN]

If you want to focus correctly for astro work, you can’t do better than a bahtinov mask. Use the rear screen to zoom in to a bright star and centre it in the screen. Then place the bahtinov mask in front of the lens. Or simply hold it there, if like the RF 14mm there are no threads. Now manually focus until you have a sharp star. You now have perfect focus for Astro, remove the mask.

For example the Kase Night Focus Tool or Kase Bright Star circular filter. I’ve used the Bright star to great effect.

Batinov Masks

100% absolutely .. tried and true and works on literally anything.

 

[blackcoffee17]

Sorry to be that guy, but the Sony 14 1.8 gm is half the price, 2/3 the weight, smaller and famously has no aberrations wide open on a 60MP sensor… the canon 14mm has to be stopped down to 2.8 to be even remotely where the Sony is… and that’s before you consider the a7cr has 1 stop better noise performance - which gives it 2.5 stops advantage … the comparison is so ridiculous that CR has ignored it from the comparison

On which planet is the Sony A7CR 1 stop better? So you telling me that ISO 6400 on the Sony is as clean as ISO 3200 on Canon?

 

[Alastair Norcross]

Sorry to be that guy, but the Sony 14 1.8 gm is half the price,

False, and it's 2/3 stop slower.

2/3 the weight, smaller and famously has no aberrations wide open on a 60MP sensor… the canon 14mm has to be stopped down to 2.8 to be even remotely where the Sony is…

False.

and that’s before you consider the a7cr has 1 stop better noise performance

False

- which gives it 2.5 stops advantage …

False

the comparison is so ridiculous

The only thing that's true, but not for the reasons you are claiming.

that CR has ignored it from the comparison

 

[Canon Rumors]

Sorry to be that guy, but the Sony 14 1.8 gm is half the price, 2/3 the weight, smaller and famously has no aberrations wide open on a 60MP sensor… the canon 14mm has to be stopped down to 2.8 to be even remotely where the Sony is… and that’s before you consider the a7cr has 1 stop better noise performance - which gives it 2.5 stops advantage … the comparison is so ridiculous that CR has ignored it from the comparison

Being wrong so many times in such a short post. A+. I'm still trying to sort out how the Sony mounts on RF

 

[neuroanatomist]

Being wrong so many times in such a short post. A+. I'm still trying to sort out how the Sony mounts on RF

Give the guy a break, he was spot on regarding one point…he definitely is “that guy“.