Hello all,
 

As the title suggests I’m interested in the Canon 180mm f/3.5 L EF Macro as I have found a barely used copy for a really good price and think it would be fun to deviate from the 105mm once in a while.

Would your recommend this lens underwater?

 

I have extensively used a FX camera in DX mode with a 105mm lens and am curious about wether a 180 by itself or cropped (equivalent focal length of 288 mm) would be too much to handle when pointing and shooting.
 

Any experiences at these focal lengths would be much appreciated!

Edited March 14, 20241 yr by zvonimiri

You'll need to perfect maneuvering the strobes at distance.

You'll be further away for many pictures. 

On 7/31/2024 at 4:39 AM, hedonist222 said:

You'll need to perfect maneuvering the strobes at distance.

You'll be further away for many pictures. 

Closest focusing distance=0.48m / 1.6 ft

There are two advantages for long focal length macro lenses, extra working distance and narrower angle of view making backgrounds easier to control.  The narrower angle means that a small move to either side can move distracting background elements out of the frame.  On land this can be a big advantage.

 

The magnification on the 180mm macro is the same 1:1 as the 105mm so no advantage.  For many subjects extra working distance is not usually needed and the extra water means more particles and potential for backscatter.  The sole exception probably being portraits of smaller fish and other subjects which can move quickly.  The extra working distance also eats into strobe power.  The narrower angle of view also won't help you UW if you have black backgrounds, though it may make it easier to exclude nearby objects at a similar distance.

 

The 180mm is a nice lens but it's one of the very first L range lenses released in the EOS system so the autofocus can be quite slow.  I have one that I have used extensively on land for insects and other subjects that are hard to approach . 

As I am the original poster of this post, I wanted to come back and give an update.

 

As you pointed out @Chris Ross, my main aim was to capture shy fish portraits with ease from a distance and use it for super macro.

 

However, I haven't even bothered borrowing or buying an extension ring for this lens the whole summer as the RF 100mm Macro is a joy to use with its 1.4x magnification together with the R6 II.

 

I have found out that the R6 II digital teleconverter options of 2x and 4x upscales back the shots to original resolution with no loss in quality and no artefacts (Canon has a great algorithm in camera). This, essentially, makes this lens a 200mm and 400mm lens, respectively. The only drawback is that you must shoot JPEG only. However, if you get your settings right in camera along with correct strobe settings and positioning, the requirement for post-processing is minimal and any JPEG can handle it. 

 

This applies both for shy fish and its super macro application. So, I will not be using this lens underwater and only for shooting on land.

 

Edited September 29, 20241 yr by zvonimiri

2 hours ago, zvonimiri said:

As I am the original poster of this post, I wanted to come back and give an update.

 

As you pointed out @Chris Ross, my main aim was to capture shy fish portraits with ease from a distance and use it for super macro.

 

However, I haven't even bothered borrowing or buying an extension ring for this lens the whole summer as the RF 100mm Macro is a joy to use with its 1.4x magnification together with the R6 II.

 

I have found out that the R6 II digital teleconverter options of 2x and 4x upscales back the shots to original resolution with no loss in quality and no artefacts (Canon has a great algorithm in camera). This, essentially, makes this lens a 200mm and 400mm lens, respectively. The only drawback is that you must shoot JPEG only. However, if you get your settings right in camera along with correct strobe settings and positioning, the requirement for post-processing is minimal and any JPEG can handle it. 

 

This applies bot for shy fish and its super macro application. So, I will not be using this lens underwater and only for shooting on land.

 

Why do this in camera with jpg when you can get the same effect cropping with a raw file? You can upsize using topaz or adobe with impressive results.

Yes @Dave_Hicks, that will yield the exact same result. Forgot to mention that.

 

For my case, I do not like spending time post-processing and therefore, I try to sort out almost everything while shooting. This also applies for me shooting on land.

 

I also have been participating in the yearly national underwater shootouts here in Turkey where you have to submit straight out of the camera JPEGs to be judged in the original resolution of the camera without any crop. Therefore, I can also say that I have more of a shootout mentality underwater when it comes to the techniques I use.

Edited September 30, 20241 yr by zvonimiri

Another advantage is the longer the focal length the better the bokeh for the same aperture and magnification:

 

 

I regularly use the Sigma 150 macro underwater and the bokeh with these images is much nicer than i was ever able to obtain when using either the Canon 100 macro or Sony 90 macro.  Downsides are that the 150 is heavier and and focus speed is slower than both of these lenses.

Edited September 30, 20241 yr by Gudge