Canon EF 8-15mm Fisheye Questions

1 minute ago, TimG said:

LOL, a buddy of mine here in Sint Maarten combined u/w photog AND rebreathers.

I could see the reason but, mercy, the amount of gear, the space he needed on the boat - and the care to set up and monitor was incredible.

Yep - for sure -- not to mention getting all the gear to wherever you are going (along with drysuits, "regular" scuba gear, etc.).

However, for diving deep wrecks, it is the "right" way to do it. OC is just too limiting IMHO.

- brett

55 minutes ago, Interceptor121 said:

I have also decided that priority is portability not absolute performance which is for sure a compromise solution

I think you make a good point there. You can add more and more pixels and better and better "image quality". But to what end?

For many of us (most of us?) looking at an image on screen does not require tons of pixels or tons of IQ. And even for commercial usage, as Alex M pointed out recently, magazine cover images need to be interesting images not megapixels. I'm still selling images taken on a Nikon Coolpix 5000. No-one has muttered about the lack of pixels or the dodgy IQ. 

Maybe if you want to create massive prints and have the house walls to handle them, then fair enough. Otherwise, what is the point? As I've written here before, we are seduced by camera manufacturer marketing. 

Moving gear around now is such a headache with airline limitations. Seems to me being able to transport gear to dive locations is now a bigger issue than having loads of megapixels and the sharpest optics.

Sorry this is all Off Topic but, hey..... 

And I'll now shut up......

28 minutes ago, TimG said:

I think you make a good point there. You can add more and more pixels and better and better "image quality". But to what end?

For many of us (most of us?) looking at an image on screen does not require tons of pixels or tons of IQ. And even for commercial usage, as Alex M pointed out recently, magazine cover images need to be interesting images not megapixels. I'm still selling images taken on a Nikon Coolpix 5000. No-one has muttered about the lack of pixels or the dodgy IQ. 

Maybe if you want to create massive prints and have the house walls to handle them, then fair enough. Otherwise, what is the point? As I've written here before, we are seduced by camera manufacturer marketing. 

Moving gear around now is such a headache with airline limitations. Seems to me being able to transport gear to dive locations is now a bigger issue than having loads of megapixels and the sharpest optics.

Sorry this is all Off Topic but, hey..... 

And I'll now shut up......

 

Going back in topic the Canon 8-15 is a superb lens. It is a bit longer than what a mirrorless lens would be however to get that quality you need glass

I am not sure Sony will do a fisheye and I am even less sure it will perform better that the 8-15 which is literally laser sharp

I find the AF of the 8-15mm much more hunty than the 28-60mm with the WWL/WACP. Surely because of the adaptor. And as such I've not considered it when evaluating the AF of the Sonys I have tried. It works fine - but the AF is definitely prone to hunting, especially with the smaller dome. I know that fisheye AF performance is rarely a deal breaker. And optically, I am very happy with the Canon lens at 61MP. 

I do think if Sony makes a native fisheye then it might be a short barrel length lens. Which would mean that there won't be space for the N100-N120 converter, currently needed for Nauticam's best domes the 140 and 230mm. And if it is really short could mean some specially designed domes. This is all wild speculation. But it is something to ponder, especially if the 8-15mm is seen a temporary solution. 

Anyone with full-resolution samples U/W with 8-15 mm with distortion correction on LR ON to be rectilinear? Thanks :)!

7 hours ago, Interceptor121 said:

Going back in topic the Canon 8-15 is a superb lens. It is a bit longer than what a mirrorless lens would be however to get that quality you need glass

I am not sure Sony will do a fisheye and I am even less sure it will perform better that the 8-15 which is literally laser sharp

I agree I wouldn't be holding my breath waiting and it's hard to imagine it being significantly better than the Canon lens.  

2 hours ago, stillviking said:

Anyone with full-resolution samples U/W with 8-15 mm with distortion correction on LR ON to be rectilinear? Thanks :)!

Reduced IQ noticeable even at web rez. Note also the significant crop. It will be a s***storm if LR does not allow one to disable this correction for forthcoming fisheye lenses.

3 hours ago, Alex_Mustard said:

I find the AF of the 8-15mm much more hunty than the 28-60mm with the WWL/WACP. Surely because of the adaptor. And as such I've not considered it when evaluating the AF of the Sonys I have tried. It works fine - but the AF is definitely prone to hunting, especially with the smaller dome. I know that fisheye AF performance is rarely a deal breaker. And optically, I am very happy with the Canon lens at 61MP. 

I do think if Sony makes a native fisheye then it might be a short barrel length lens. Which would mean that there won't be space for the N100-N120 converter, currently needed for Nauticam's best domes the 140 and 230mm. And if it is really short could mean some specially designed domes. This is all wild speculation. But it is something to ponder, especially if the 8-15mm is seen a temporary solution. 

Which adapter are you using? They are not all the same in fact

The AF on my A1 is super snappy as it was on my GH5. Sure I have not taken the Sony underwater but I would be surprised by any hunting

3 hours ago, stillviking said:

Anyone with full-resolution samples U/W with 8-15 mm with distortion correction on LR ON to be rectilinear? Thanks :)!

It is not a good idea as obviously corners are very low resolution and the amount of crop becomes considerable

9 hours ago, Interceptor121 said:

Which adapter are you using? They are not all the same in fact

The AF on my A1 is super snappy as it was on my GH5. Sure I have not taken the Sony underwater but I would be surprised by any hunting

I have a Metabones adaptor. I have not tried others.

I only have 3 lenses with the Sony A7RV I have here. The 28-60mm with the WWL/WACP definitely focuses much better than my reference Nikon 28-70mm with WACP on D850. The 90mm is much better at tracking fish than the Nikon 105mm. Although the 90mm is less impressive at smaller macro and looses its advantage over the 105mm/D850 combo.

However, the 8-15mm Canon/Metabones does not focus as well as the Nikon 8-15mm on D850. When both are confident, they both snap onto the subject so instantly that there is not significant difference between them and no real point in commenting on the performance as even if one was better it would not really be worth commenting on. However, with strongly backlit, monochromatic, strange shaped subjects (as most wide angle foregrounds look to a camera underwater) the 8-15mm Canon will hunt at times. This is much more prevalent with a smaller dome port. The hunting is common enough for me to want to comment on. But while it has slowed me down shooting, I've not missed any shots. The best solution is to switch to back button/thumb focus (Focus With Shutter Off in Sony-speak) with this lens.

So overall, I find the A7RV to be the best autofocusing underwater cameras I have used. It is logical to expect the A1 to be better. But it also clearly has areas of strength, and areas of weakness. The latter really a result of Sony's poor lens availability for underwater shooting, which hopefully will be redressed. 

Alex

4 minutes ago, Alex_Mustard said:

I have a Metabones adaptor. I have not tried others.

I only have 3 lenses with the Sony A7RV I have here. The 28-60mm with the WWL/WACP definitely focuses much better than my reference Nikon 28-70mm with WACP on D850. The 90mm is much better at tracking fish than the Nikon 105mm. Although the 90mm is less impressive at smaller macro and looses its advantage over the 105mm/D850 combo.

However, the 8-15mm Canon/Metabones does not focus as well as the Nikon 8-15mm on D850. When both are confident, they both snap onto the subject so instantly that there is not significant difference between them and no real point in commenting on the performance as even if one was better it would not really be worth commenting on. However, with strongly backlit, monochromatic, strange shaped subjects (as most wide angle foregrounds look to a camera underwater) the 8-15mm Canon will hunt at times. This is much more prevalent with a smaller dome port. The hunting is common enough for me to want to comment on. But while it has slowed me down shooting, I've not missed any shots. The best solution is to switch to back button/thumb focus (Focus With Shutter Off in Sony-speak) with this lens.

So overall, I find the A7RV to be the best autofocusing underwater cameras I have used. It is logical to expect the A1 to be better. But it also clearly has areas of strength, and areas of weakness. The latter really a result of Sony's poor lens availability for underwater shooting, which hopefully will be redressed. 

Alex

Alex

When you attach the metabones there is a little led on the side of the converter. It can either have blue or red color

What color is on your adapter? This can be configured and controls how focus works

12 hours ago, Interceptor121 said:

It is not a good idea as obviously corners are very low resolution and the amount of crop becomes considerable

So in a EF 8-15 mm vs RF 16 mm battle if I want straight lines (really don't enjoy Fisheye distortion effects) maybe even RF 16 mm is better, because 15 mm corners will also have few resolution and crop will look at least 16 mm..

4 minutes ago, stillviking said:

So in a EF 8-15 mm vs RF 16 mm battle if I want straight lines (really don't enjoy Fisheye distortion effects) maybe even RF 16 mm is better, because 15 mm corners will also have few resolution and crop will look at least 16 mm..

If  you want straight lines you shoot a rectilinear lens. Correcting a fisheye lens to rectilinar normally looks much worse than a rectilinear lens after you have cropped the image

A fisheye lens in my mind is for shots where you are not aware of the shape of things and the geometry 

When having real proportion is a requirement across the same you need a solution with an acceptable amount of distortion

19 hours ago, Interceptor121 said:

If  you want straight lines you shoot a rectilinear lens. Correcting a fisheye lens to rectilinar normally looks much worse than a rectilinear lens after you have cropped the image

A fisheye lens in my mind is for shots where you are not aware of the shape of things and the geometry 

When having real proportion is a requirement across the same you need a solution with an acceptable amount of distortion

Agree, using a fisheye for what it is good at the fisheye distortion is not really apparent, you do have to pick the angle you shoot from and what you include in the frame and watch the corners, but for what a fisheye is good at - a rectilinear wide is not a great substitute.  I'm talking CFWA, reef scenics and really big animals.  The rectilinear is more suited to wrecks perhaps and also comes into play when you need more reach for shier subjects, but the penalty is poor corner performance and needing a 230mm dome to do its best.

Put it another way when talking about which lens to use you really need to specify the subject matter.

8 minutes ago, ChrisRoss said:

Agree, using a fisheye for what it is good at the fisheye distortion is not really apparent, you do have to pick the angle you shoot from and what you include in the frame and watch the corners, but for what a fisheye is good at - a rectilinear wide is not a great substitute.  I'm talking CFWA, reef scenics and really big animals.  The rectilinear is more suited to wrecks perhaps and also comes into play when you need more reach for shier subjects, but the penalty is poor corner performance and needing a 230mm dome to do its best.

Put it another way when talking about which lens to use you really need to specify the subject matter.

The example posted by Tom is not a good example as it is #1. a split shot, where the over water region is, of course, not in focus and #2.: it is CFWA, where the DOF region is thin and most of parts of the image are not in focus, even under the water. Stretching out the unsharp regions will results in complete destruction of IQ, as is shown...

In my experience, partial fisheye correction in LR does not degrade image quality. I frequently use this for images, e.g. from divers or from wrecks...

100% correction is, of course, too much - for a 180° fisheye this would equal a rectilinear WA lens with less than 1mm focal length that does not exist - I doubt that IQ would be better with such a lens if it would exist. Correction also requires a good lensprofile that is often non-existing (e.g. for WWL/WACP) and needed to be made in DIY mode...

Maybe, in order not to hijack this thread, we should open up a separate thread on fisheye correction were we post more examples and discuss in detail...

Wolfgang

On 1/20/2023 at 12:09 PM, Interceptor121 said:

When you attach the metabones there is a little led on the side of the converter. It can either have blue or red color

What color is on your adapter? This can be configured and controls how focus works

This could definitely be a factor, but I don't know the answer. The Metabones adaptor I am using does not have a LED on it. It has a red dot on it to help line up the lens - see picture. 

I would expect it to be a good one, as my friend who has lent it to me usually has all the best gear (hence why he has a A7RV and housing to lend). Tape is to stop the lens zooming to any of the useless focal lengths!

Regarding FE correction - a big issue for me is that if you plan to routinely correct fisheye shots - the compositions that are are deciding on underwater, though your viewfinder, really aren't the ones you are getting in your final shots. You are trusting a reasonably amount to guesstimates for pleasing looking framing. 

This could definitely be a factor, but I don't know the answer. The Metabones adaptor I am using does not have a LED on it. It has a red dot on it to help line up the lens - see picture. 

I would expect it to be a good one, as my friend who has lent it to me usually has all the best gear (hence why he has a A7RV and housing to lend). Tape is to stop the lens zooming to any of the useless focal lengths!
 

I am probably just being dumb. But I have it on the camera and I am taking photos, and I really can't see any LED on my adaptor. Can you find a picture of one online and share, so that I know what I am looking for.

I am probably just being dumb. But I have it on the camera and I am taking photos, and I really can't see any LED on my adaptor. Can you find a picture of one online and share, so that I know what I am looking for.