Choosing a camera format for Underwater Photography

[Interceptor121]

Can you point me to one of your shot and tell me what equipment you have? Orcas shots I have seen are snorkelling and therefore shallow
I have seen shots taken with GH5 and were a bit grainy indeed but nothing a good post processing could not cure

 

[Interceptor121]

The fastest lens equivalent to your 12mm is the Nikkor 24-85 that is f/3.5 and therefore a D5 would give you 0.33 Ev vs cost of 5000 euros plus frankly not worth it
A better solution would be a metabones speedbooster on your GH5 with an extension ring 30+35 and a Nauticam WACP that would give you 0.66 Ev
Or the same sigma 18-35 on APSC that would be f/1.8 but have 1 stop advantage
If I were you I would consider housing the Panasonic 12mm 1.4 (I have this lens) that will give you another stop. If you have a Nauticam housing I can probably help you building the right extension or choosing the right port

 

[tarponchik]

If you shoot macro or close-ups of slow or immovable objects, this may be true. If you shoot fish schools or dolphin pods at 40 ft on a cloudy day, or coral reef landscape, there is no way your strobes will help you. You can't shoot at exposures longer than 1/250, and the depth of field requirement pushes your aperture to f/4.5-5.6 (for APS-C). Moreover, most lenses peak their performance at f/4.5-5.6. Hence, your ISO is pushed up and size matters.

 

[Interceptor121]

It still won't matter f/4.5-f/5.6 are pretty slow lenses equivalent to f/3.5 for MFT (widely available) and f/7.1 Full frame if you wanted to go there

To give you an example if you wanted to compare fisheye (I would not shoot a fisheye at less than f/4-f/5.6-f/8 respectively) Olympus has a 1.8 lens this is 2.4 in APSC and 3.5 in full frame. Sure you could go and shoot a sigma at f/2.8 on full frame but this is not the most common use case and at the end the benefit is 0.7 Ev all netted out
Between APSC and MFT in particular the Ev difference is 0.8 Ev is really very little to make considerations of any sort

Full frame 2 Ev away is where you wanted to be if you had special cases. At the end is down to user preference but for the large majority of use cases the DOF equivalence and availability of lenses balances everything out. If you really want to shoot in low light go and get a Nauticam WACP and a full frame camera this combination is the strongest on the field but it has a significant cost as well then you can shoot f/5 on full frame and have more sharpness lower ISO and at the end best IQ

 

[Interceptor121]

By the way fish schools at 40 ft are not an issue and I shoot them with strobes

Snapper Photography by Interceptor121, on Flickr
This is at 20 meters which is 65 feet I think

 

[Interceptor121]

Also I want to clarify that at wide angle the issue is not depth of field but field of curvature of a dome that is resolved stepping down
If you dont the image gets soft in the edges and off centre
This has nothing to do with depth of field for macro in fact for macro a full frame camera may offer a better color rendition than smaller format
DOF equivalence is done to balance light and coincidentally works in favour of smaller sensor when using domes
I will update the article as clearly some concepts are unclear

 

[Storker]

it just depends

This.

One size doesn't fit all. Different situations, different demands, different optimal solutions. It all depends.

 

[Interceptor121]

This.

One size doesn't fit all. Different situations, different demands, different optimal solutions. It all depends.

Who said that? The important thing is not to make assumptions based on incorrect facts there are so many misconceptions around it is frightening then once you know you can make informed decisions. Sensor format is just one aspect of the choice then comes availability of lenses and ports, ergonomics, other performance etc etc etc

 

[Storker]

at equivalent DOF

You seem rather fixated on DOF. What if DOF isn't the end-all, be-all, but if decent SNR is more important than optimal DOF?

Many of us shoot under less than optimal conditions. Often, we have to decide on our priorities. Which are given by the situation at hand, not by some keyboard warrior musings. And we have to choose what to let go. Which may be different from what you choose. What you choose may well be perfect for you, but don't bet your savings that it's perfect for everybody else. Which you seem to do.

I, like you, have chosen to shoot m43 under water. Because given all the pros and cons, it's the best solution for me. I know people who choose to shoot 24x36. Instead of quarreling with them, strongly believing that my solution is the best for them, I choose to accept that they have other priorities and that they - who more than often present as at least as competent as I am - have weighed the pros and cons differently.

 

[Storker]

Who said that?

I did. And you quoted it.