Pros - Cons Switching from DSLR to Mirrorless?

I’m a long time UW shooter from Nikonos II, V to Aquatica w/ Canon F1n Film to finally Seacam w/ Canon 1Ds Mark II (2005) which still works to this day but is long in the tooth. I currently shoot a Canon 5D Mark IV and Canon 1Dx Mark II above water and am thinking of:

1. House the 5D Mark IV in a Seacam and get immediate use with current lenses and ports.

2. Wait for the R5 Seacam housing to come out (but would have to use an adapter for my fisheye and macro lenses until Canon makes RF versions)

3. Jump ship to Sony A7R IV w/ Seacam housing and use my existing ports and viewfinder.

For underwater use, is the optical viewfinder still better more desirable over the EVF on mirrorless cameras? I would love to hear from someone who has made the switch between a DSLR and Mirrorless in the UW environment on the pros/cons. 

Thanks, Keith

You could indeed switch to the Sony but the  Sony with Metabones is reported to work well with Canon 8-15 and presumably other fisheye lenses, but AF with Canon macro is another matter and may be suspect.  Sony flash sync speed limitation in manual - 1/250 is only available in TTL as I recall and drops back to a lower speed in manual.

The Canon is going to be much more likely to AF well with your Canon lenses.  The Metabones adapters are there and work surprisingly well, but you are translating from one system to another, while the Canon adapter is much more likely to play well with your current lenses.

Assuming that you use strobes - on that old camera I guess you have electrical sync cables - it is more likely they will transfer across directly to a new Canon system.

You mention a view finder -is that an external viewfinder you plan to migrate over?  I know that there is a known issue with the EVF on Sony A7 mKIV using Nauticam's viewfinders - the viewfinder is universal - except on the Sony viewfinder.  May or may not apply to your viewfinder.  see this thread:

View archived post in: Nauticam viewfinder slr vs mil

After shooting Canon dSLRs for many years I switched to a Sony A7RIV earlier this year and am very happy with the switch.

All my Canon EF and EF-S lenses as well as other brands using these mounts (Tokina and Sigma) work very well on the A7RIV plus metabones adapter with no autofocus issues.  In fact, I would say that auto focus with my Canon 60 and 100 macros and Sigma 150 was better with the A7RIV than my old 7D MkII with the same lenses (AF-C with tracking flexible spot rocks for macro, none of my Canons had this).  I now have a Sony 90 macro lens and it is better all around lens than the Canon mount macro lenses I have.  I will be selling the Canon 60 and 100 macro lens and continue on with the Sony 90, Sigma 150 and Canon 8-15 fisheye.  Above water I will continue to use my Canon 70-200 f4 as I am getting excellent results with this lens on the A7RIV with Metabones adapter.

As to the reported issued with seeing all the viewfinder in a Nauticam housing using a 45° degree viewfinder I have had no problems at all.  I would suggest that the problem is dependent on how close you can get your eye to the 45° viewfinder eyepiece.  I have a very low volume mask, perhaps the person who reported the issue uses a higher volume mask and can't get their eye as close to the viewfinder eyepiece as I can.

As to the EVF vs optical viewfinder, at first I thought it would be a problem but after a couple of dives I don't really notice the difference anymore.  The ability to review a shot immediately after taking it in the viewfinder without having to take you eye away from the viewfinder and move the camera so you can review in the LCD on the back of the camera is a huge advantage.

12 hours ago, ChrisRoss said:

You could indeed switch to the Sony but the  Sony with Metabones is reported to work well with Canon 8-15 and presumably other fisheye lenses, but AF with Canon macro is another matter and may be suspect.  Sony flash sync speed limitation in manual - 1/250 is only available in TTL as I recall and drops back to a lower speed in manual.

The Can8

You mention a view finder -is that an external viewfinder you plan to migrate over?  I know that there is a known issue with the EVF on Sony A7 mKIV using Nauticam's viewfinders - the viewfinder is universal - except on the Sony viewfinder.  May or may not apply to your viewfinder.  see this thread:

View archived post in: Nauticam viewfinder slr vs mil

 

Thanks Chris! The viewfinder is Seacam S180 viewfinder and may very well have same issue as the Nauticam, but I am not sure. I have heard from another professional UW photographer, that he personally won’t switch to mirrorless now because he feels the DSLR optical viewfinder is superior to the EVF in a mirrorless camera. This is one reason I was thinking of housing a Canon 5D Mark IV. I currently use Inon strobes with Nikonos connectors. 

12 hours ago, Gudge said:

After shooting Canon dSLRs for many years I switched to a Sony A7RIV earlier this year and am very happy with the switch.

All my Canon EF and EF-S lenses as well as other brands using these mounts (Tokina and Sigma) work very well on the A7RIV plus metabones adapter with no autofocus issues.  In fact, I would say that auto focus with my Canon 60 and 100 macros and Sigma 150 was better with the A7RIV than my old 7D MkII with the same lenses (AF-C with tracking flexible spot rocks for macro, none of my Canons had this).  I now have a Sony 90 macro lens and it is better all around lens than the Canon mount macro lenses I have.  I will be selling the Canon 60 and 100 macro lens and continue on with the Sony 90, Sigma 150 and Canon 8-15 fisheye.  Above water I will continue to use my Canon 70-200 f4 as I am getting excellent results with this lens on the A7RIV with Metabones adapter.

As to the reported issued with seeing all the viewfinder in a Nauticam housing using a 45° degree viewfinder I have had no problems at all.  I would suggest that the problem is dependent on how close you can get your eye to the 45° viewfinder eyepiece.  I have a very low volume mask, perhaps the person who reported the issue uses a higher volume mask and can't get their eye as close to the viewfinder eyepiece as I can.

As to the EVF vs optical viewfinder, at first I thought it would be a problem but after a couple of dives I don't really notice the difference anymore.  The ability to review a shot immediately after taking it in the viewfinder without having to take you eye away from the viewfinder and move the camera so you can review in the LCD on the back of the camera is a huge advantage.

Thanks Gudge! This helps to clarify the viewfinder issues. I don’t use the Seacam 45 viewfinder but want to add that to my next housing for macro. I love the S180 viewfinder I have used for the last 15 years except when wanting to get low for a shot. Have you noticed any issues with the EVF in bright sunlight like shooting upwards with the sun in the frame?  

9 hours ago, kcf955 said:

Have you noticed any issues with the EVF in bright sunlight like shooting upwards with the sun in the frame?

Not something I've thought about, but noting that I don't recall having issues with the EVF but can recall a couple of times that I have been blinded by the sun while using an optical viewfinder for such shots, I'd say no.

I'd like to add that after using film and digital SLRs underwater for 36 years I was one of those guys who would never use an EVF because they couldn't match an optical viewfinder.  My main concern was that they weren't good enough to "lock and rock" for macro shooting.  The A7RIV's EVF proved me wrong, it performs very nicely for "locking and rocking" specially when used with the focus peaking display while focusing manually (see comment below).

Another advantage of the A7RIV when using Sony E mount lenses is that you can switch the lens to manual focus mode via the camera (vs using the switch on the lens) and have focus peaking display in the EVF while focusing manually.  This is not possible with my Canon lenses on the Metabones adapter.

Great, thank you for the additional information. Its good to hear your experience with the EVF and Sony's system.

 I have a R5 on order and I guess at this point will have to see if I want to wait for housings to come out or stick with my 5DIV and get a housing sooner. 

On 7/28/2020 at 9:56 AM, ChrisRoss said:

Sony flash sync speed limitation in manual - 1/250 is only available in TTL as I recall and drops back to a lower speed in manual.

I believe this comment may be based on my comments on the A7RIV's sync speed in this thread:

View archived post in: Dark bands with Z6 and YS-D1 TTL

I've just been playing around with my wife's and my strobes and now the A7RIV is syncing perfectly at 1/250 as I have reported in my latest comment in that thread.  I have no idea why, I haven't changed any settings.  It was only missing syncing at 1/250 when I first got it with a very small black band I could easily frame/crop around (easy to do when you've got 61MP to play with).  This small band has now disappeared when I use the strobes at 1/250 shutter speed.  Maybe the shutter has loosened up little with a bit of use and reacts fast enough now to sync at 1/250.

Any number of reasons it might change - technically the limitation is that the focal plane shutter is never fully open and the second curtain starts to close before the first finishes opening so you have a wide slot moving across the frame.  This is unlikely to be different between the 1/200 of non Sony strobes and 1/250 with Sony strobes.  1/250 needs to have the shutter open fully before the second curtain starts to move no matter what if any strobe is achieve sync at that speed.  In any case the shutter needs to move at the same speed for shutter speeds to remain accurate.

The flash needs to trigger just as the first curtain fully opens and the strobe needs to dump its full output before the second curtain starts to close .  The concern is the delay of triggering the strobe once the camera sends the signal to trigger the flash - the LED needs to power up, the flash slave sensor needs to react and the strobe needs to dump.  For this to change the flash needs to get it's triggering slightly sooner.