Laowa FFII 10mm F2.8 coming soon

[Malm]

View attachment 213773
The lens diagram is not to scale is it? Those are some awfully small looking lens elements for a 10mm f2.8.

Based on the image of that lens: That is unfortunately the correct scale of the lenses and it makes sense. A 10/2.8 lens is collecting halve the amount of light as a 14/2.8 lens (14/2.8=5mm, so pi * 5^2 = pi * 25 versus 10/2.8=3.57mm, so pi * 3.57^2 = pi * 12.8). So even that the MTF curve is looking promising (has to be confirmed by real photos), a 10/2.8 Laowa would be a poor replacement for a 14/2.8 lens for night/astro photography. It can be of interest in certain situations (e.g. very wide polar light) which did not allow for stitching or for tracked images. I'm recently using the good Samyang XP 10/3.5 lens for such extreme aurora events and if the (astro) quality of the Laowa 10/2.8 is good I might change. Based on my experience with the Laowa Zero-D 12/2.8 and reviews in the internet I'm not really convinced by Laowa lenses. They have a good quality for the price, but there are better (astro) lenses on the market in a similar price range (e.g. Samyang XP).
The difference in the size of the front lens between the Samyang XP 10/3.5 and this Laowa 10/2.8 is really big, so I'm getting interested how good this Laowa lens will be (and if I have to change my opinion).

 

[scyrene]

Eye of newt?

 

[mxwphoto]

Based on the image of that lens: That is unfortunately the correct scale of the lenses and it makes sense. A 10/2.8 lens is collecting halve the amount of light as a 14/2.8 lens (14/2.8=5mm, so pi * 5^2 = pi * 25 versus 10/2.8=3.57mm, so pi * 3.57^2 = pi * 12.8). So even that the MTF curve is looking promising (has to be confirmed by real photos), a 10/2.8 Laowa would be a poor replacement for a 14/2.8 lens for night/astro photography. It can be of interest in certain situations (e.g. very wide polar light) which did not allow for stitching or for tracked images. I'm recently using the good Samyang XP 10/3.5 lens for such extreme aurora events and if the (astro) quality of the Laowa 10/2.8 is good I might change. Based on my experience with the Laowa Zero-D 12/2.8 and reviews in the internet I'm not really convinced by Laowa lenses. They have a good quality for the price, but there are better (astro) lenses on the market in a similar price range (e.g. Samyang XP).
The difference in the size of the front lens between the Samyang XP 10/3.5 and this Laowa 10/2.8 is really big, so I'm getting interested how good this Laowa lens will be (and if I have to change my opinion).

I am not too clear on the calculation. Shouldn't lenses set to f2.8 have same light exposure to sensor regardless of focal length (assuming no wild differences in T stop)?

 

[dancan]

I am done with Laowa in general!
I tested the 2,8 Zero D 12mm for my Canon R5 and it was a nightmare in comparison with the Sigma Art 12-24.
Meanwhile I am absolutely happy with the new 10-20 from Canon which saves so much weight and is even sharper!

 

[Malm]

I am not too clear on the calculation. Shouldn't lenses set to f2.8 have same light exposure to sensor regardless of focal length (assuming no wild differences in T stop)?

No. What counts is the 'light gathering' of the lens and that is the lens aperture area. And the area of a circle is r^2 * pi with 2 * r = diameter = focal length / max aperture (e.g. 10 / 2.8). That's why ultra-wide angle (UWA) lenses aren't that well suitable for MW images (poor light gathering) and many photographers use fast 24mm or 35mm lenses instead for a panorama. The advantage of UWA lenses is the simplicity (no stitching). Here an in-depth article with more details and examples about that topic: https://clarkvision.com/articles/ch...-and-lenses-for-nightscape-astro-photography/

 

[neuroanatomist]

What counts is the 'light gathering' of the lens and that is the lens aperture area.

While that’s true (on these forums it’s often discussed in terms of SNR for telephoto lenses), it’s not the only factor. The other big one is exposure time.

IMO, the distinction between casual and serious ILC astro shooters comes down to whether or not you have a tracking mount. For casual shooters (myself included), a wider AoV enables a longer exposure without star trails. With the 500/FL approximation, a 10mm lens allows a 50 s exposure, 3.6 times longer than with a 35mm lens.

If lens aperture area were all that mattered, my 600/4 at ~150mm diameter would be the best choice for astro.

 

[Nemorino]

If lens aperture area were all that mattered, my 600/4 at ~150mm diameter would be the best choice for astro.

Didn't Canon gave a couple of 400 2.8 II to a university or similar for astro work after releasing the third version? I remember someone posted a link on CR.

 

[neuroanatomist]

Didn't Canon gave a couple of 400 2.8 II to a university or similar for astro work after releasing the third version? I remember someone posted a link on CR.

More than a couple. Was called the Dragonfly, IIRC. But I suspect they used the array with a tracking mount.

 

[Nemorino]

Yes! That is what I had in mind!
Serious sientific work for sure.

 

[EricN]

No. What counts is the 'light gathering' of the lens and that is the lens aperture area. And the area of a circle is r^2 * pi with 2 * r = diameter = focal length / max aperture (e.g. 10 / 2.8). That's why ultra-wide angle (UWA) lenses aren't that well suitable for MW images (poor light gathering) and many photographers use fast 24mm or 35mm lenses instead for a panorama. The advantage of UWA lenses is the simplicity (no stitching). Here an in-depth article with more details and examples about that topic: https://clarkvision.com/articles/ch...-and-lenses-for-nightscape-astro-photography/

Not being much for astro photography, I only read the "ethics" part and took a look about equipment. Very interesting, thanks for the link!

 

[EricN]

More than a couple. Was called the Dragonfly, IIRC. But I suspect they used the array with a tracking mount.

My memory is not great but dragonfly array sounds right.

 

[mxwphoto]

No. What counts is the 'light gathering' of the lens and that is the lens aperture area. And the area of a circle is r^2 * pi with 2 * r = diameter = focal length / max aperture (e.g. 10 / 2.8). That's why ultra-wide angle (UWA) lenses aren't that well suitable for MW images (poor light gathering) and many photographers use fast 24mm or 35mm lenses instead for a panorama. The advantage of UWA lenses is the simplicity (no stitching). Here an in-depth article with more details and examples about that topic: https://clarkvision.com/articles/ch...-and-lenses-for-nightscape-astro-photography/

I read the article and understand what it is saying. I suppose it all boils down to the right tool for the right job.

You can certainly use a 24 or 35mm 1.2 and stitch a pano for Milky Way and get greater resolution, finer detail, and lower SNR. That said, if it comes to aurora and other types of environmental night photography (or if one just want simplicity as it will more likely be a desktop wallpaper than printed 80" across), 10mm 2.8 one shot will reign supreme.

I for one would be fairly interested in seeing how this Laowa performs vs the 11-24.

 

[tron]

For astrophotography, it depends whether or not the lens will not have serious coma issues. A little can be acceptable, a lot is a problem. Just my opinion.

 

[tron]

Just a few more remarks. Astrophoto tests with my 5DMkIV and R5 showed that the 500 rule is not enough. I see star trails at 100% magnification.

For example 14mm at 30sec which multiplied gives 420 gets star trails. To get rid of them I have to use around 15 sec but sometimes I use 20sec to save on ISO which gets a hit anyway.

Also, to lower ISO I use Sigma 14mm 1.8

I have an amateur mount which is enough for wide angle shots but the issue is when I want to include foreground too. I like landscape astrophotography a lot more.

I would like to avoid taking two shots and combining because I would feel a little like cheating. On the other hand I do not publish anywhere so all the photos are just for me (but it's the same because I know!)

Also since the tracking mount does not have 1/2 sidereal tracking option I could try to cut its power in the middle of a say 30 sec (so 15sec) exposure to avoid blurring foreground - just an untested thought - but it is a little too much.

Eventually digital cameras coupled with lenses like 14mm 1.8 or 10mm 2.8 may improve so much that all the above could be unnecessary.

Lastly, I rarely have the opportunity to be in areas that are not light polluted so maybe I am overthinking...

 

[tron]

I am done with Laowa in general!
I tested the 2,8 Zero D 12mm for my Canon R5 and it was a nightmare in comparison with the Sigma Art 12-24.
Meanwhile I am absolutely happy with the new 10-20 from Canon which saves so much weight and is even sharper!

Thanks for the info. But, could you please elaborate? Which issues did you have?

 

[dancan]

Sharpness in corners was so bad, I just couldn't believe it. I tried a second copy which was the same!
I tried to get in touch with Laowa but even this did not work.
As I already wrote the Sigma Art 12-24 is pretty good in the corners, the Canon 10-20 is superb!!!

 

[tron]

Sharpness in corners was so bad, I just couldn't believe it. I tried a second copy which was the same!
I tried to get in touch with Laowa but even this did not work.
As I already wrote the Sigma Art 12-24 is pretty good in the corners, the Canon 10-20 is superb!!!

Thanks! This is useful info.

 

[P-visie]

Just a few more remarks. Astrophoto tests with my 5DMkIV and R5 showed that the 500 rule is not enough. I see star trails at 100% magnification.

For example 14mm at 30sec which multiplied gives 420 gets star trails. To get rid of them I have to use around 15 sec but sometimes I use 20sec to save on ISO which gets a hit anyway.

Also, to lower ISO I use Sigma 14mm 1.8

I have an amateur mount which is enough for wide angle shots but the issue is when I want to include foreground too. I like landscape astrophotography a lot more.

I would like to avoid taking two shots and combining because I would feel a little like cheating. On the other hand I do not publish anywhere so all the photos are just for me (but it's the same because I know!)

Also since the tracking mount does not have 1/2 sidereal tracking option I could try to cut its power in the middle of a say 30 sec (so 15sec) exposure to avoid blurring foreground - just an untested thought - but it is a little too much.

Eventually digital cameras coupled with lenses like 14mm 1.8 or 10mm 2.8 may improve so much that all the above could be unnecessary.

Lastly, I rarely have the opportunity to be in areas that are not light polluted so maybe I am overthinking...

The 500 rule is not a ‘good’ rule for astrophotography with high mpx sensors. You should use the NPF rule. Here is a link to an article on petapixel. Apps like Photopills have a calculator for the NPF rule.

 

[tron]

The 500 rule is not a ‘good’ rule for astrophotography with high mpx sensors. You should use the NPF rule. Here is a link to an article on petapixel. Apps like Photopills have a calculator for the NPF rule.

Thanks. I just decrease the number of seconds (practically increase the speed) until I am satisfied with the result. Star trails depend also on the specific part of the sky being photographed so I take some test photos until I am satisfied with the result.

 

[Surab]

What is your experience with the Laowa 15mm F2 Zero-D lens?