Hi all,

I’m building an underwater rig for my Sony A7RIII and would love some advice from those with experience using different lenses underwater.

What I have:

• Seafrogs case with a macro port and a 6 and 8 inch dome

• S&S strobes

• Sigma 15mm f2.8 fisheye (adapted from canon)

• Planning to get the Tamron 90mm macro later down the line

Now I’m looking for a versatile zoom to fill the gap. Based on my research, here are the three I’m considering, along with what I see as their main pros:

• Tamron 17-50: close focus on the wide end, good zoom range, fixed length, affordable

• Sony 20-70: useful zoom range, would also be my main lens topside, good magnification on the long end

• Sony 16-35 PZ: widest of the three, no zoom gear needed, fixed length, sharp

Would love to hear from anyone who has used two or more of these, especially underwater. Which would you pick, if any!

I would delay this choice until I have a better understanding of what I like to shoot, but it affects my choice of topside lenses too (new to the hobby all together), so looking to form an early opinion

Thanks!

Edited Monday at 05:55 AM1 day by dimsak
Slight updates for clarity

Hey dimsak

I'm sure you'll get lots of great advice on the qualities of each. I'd like to give you a different perspective:

My experience has been that a fisheye and a macro are the essentials - anything else is marginal and I'm not convinced by the need for something mid-range.

The fisheye covers the vast majority of wide-angle stuff unless you are determined to use a rectilinear lens. Then a macro lens covers the majority of the fish portrait and macro type images. You have the excellent Sigma 15mm; and are planning the macro.

The only potential use for a mid-range, for me, is maybe pelagic that won't come close. But even then, really marginal use

I've found it better to plan the dive setup for macro or fisheye and then search for subjects that fit that criteria. Mid-range is very much neither here nor there.

My advice: save your cash.

I can only say about the Sony 20-70mm, that I use behind Zen DP170. It is very sharp, maybe it is the lens with the sharpest UW performance that I have.

For me 20mm at the wide end is plenty of rectilinear WA and it is very useful for zooming in (I also have the Laowa 10mm, but used it so far only twice - I personally find rectilnear at such wide angle distracting). I use it mostly for fish portraits (and moderate WA), the focal length depends on how shy the creatures are, but I try to go to the minimum possible...

When a wider angle than 20mm is needed, I use fisheye (Canon 8-15mm w/o and with Sony 2x TC; WACP-C/Sony 28-60mm), similar to what Tim was writing...

Wolfgang

I would suggest matching your UW lenses to what you might want to shoot UW. UW shooting is different in that the goal is to get close to minimize the amount of water between you and your subject. Not all good lenses translate well into UW shooting - the main requirement is close focusing and even then it pays to choose lenses that are proven UW performers.

A lot depends on what you shoot and in in what conditions. Clean tropical waters are somewhat different to shooting in temperate waters where there may be lower visibility and more particulate matter to deal with. In the tropics for WA I like my adapted Canon 8-15 for wide angle work and it works nicely for CFWA as well. In temperate waters the narrower fields of something like a 20-24 lens are a little easier to deal with and you can swap between things like fish schools and larger single fish, big nudis and other critters which are physically large enough to shoot with a mid range zoom.

The Tamron 17-50 I don't know I've heard of anyone using UW, the min focus at the long end seems a bit too long to work well UW. The 20-70 on the other hand has been used by a few people on the forum and is reported to work well. The 6 and 8" seafrogs domes might be a little small and not have ideal extensions to work with lenses in the 16-17mm range and corner performance may suffer. This becomes less critical at narrower angles of view and 20-24 lenses will not have the same penalty. Fisheye lenses are different and work quite well in smaller dome sizes.

Personally I would try using what you have now for a while and see what you find you are missing out on in experience. Again though this might vary depending on where you are diving and the subjects you find you like.

Also consider a pre-owned Sony Zeiss 16-35 f4 which may be the lowest cost option with Seafrogs.

3 hours ago, TimG said:

Hey dimsak

I'm sure you'll get lots of great advice on the qualities of each. I'd like to give you a different perspective:

My experience has been that a fisheye and a macro are the essentials - anything else is marginal and I'm not convinced by the need for something mid-range.

The fisheye covers the vast majority of wide-angle stuff unless you are determined to use a rectilinear lens. Then a macro lens covers the majority of the fish portrait and macro type images. You have the excellent Sigma 15mm; and are planning the macro.

The only potential use for a mid-range, for me, is maybe pelagic that won't come close. But even then, really marginal use

I've found it better to plan the dive setup for macro or fisheye and then search for subjects that fit that criteria. Mid-range is very much neither here nor there.

My advice: save your cash.

2 hours ago, Chris Ross said:

I would suggest matching your UW lenses to what you might want to shoot UW. UW shooting is different in that the goal is to get close to minimize the amount of water between you and your subject. Not all good lenses translate well into UW shooting - the main requirement is close focusing and even then it pays to choose lenses that are proven UW performers.

A lot depends on what you shoot and in in what conditions. Clean tropical waters are somewhat different to shooting in temperate waters where there may be lower visibility and more particulate matter to deal with. In the tropics for WA I like my adapted Canon 8-15 for wide angle work and it works nicely for CFWA as well. In temperate waters the narrower fields of something like a 20-24 lens are a little easier to deal with and you can swap between things like fish schools and larger single fish, big nudis and other critters which are physically large enough to shoot with a mid range zoom.

The Tamron 17-50 I don't know I've heard of anyone using UW, the min focus at the long end seems a bit too long to work well UW. The 20-70 on the other hand has been used by a few people on the forum and is reported to work well. The 6 and 8" seafrogs domes might be a little small and not have ideal extensions to work with lenses in the 16-17mm range and corner performance may suffer. This becomes less critical at narrower angles of view and 20-24 lenses will not have the same penalty. Fisheye lenses are different and work quite well in smaller dome sizes.

Personally I would try using what you have now for a while and see what you find you are missing out on in experience. Again though this might vary depending on where you are diving and the subjects you find you like.

Thanks Tim, Chris.

My initial plan was to not buy anything more yet (as you also suggest)

What has lead me to these thoughts is the fact that I will also need a "main" topside lens.

There I was considering the 28-200 tamron, with the 20-70 sony being a close second. The 20-70 being useful underwater could tip the scales.

I am currently optimizing for a trip to the Galapagos, do you think the 20-70 could be useful there (i.e., would you ever pick it over the 15mm fisheye?)

Aware that this is a. very specific questions and you may not have a view on the matter :) I am just not familiar at all with what subjects at different distances look like in different focal lengths!

Dimi

3 hours ago, Architeuthis said:

I can only say about the Sony 20-70mm, that I use behind Zen DP170. It is very sharp, maybe it is the lens with the sharpest UW performance that I have.

For me 20mm at the wide end is plenty of rectilinear WA and it is very useful for zooming in (I also have the Laowa 10mm, but used it so far only twice - I personally find rectilnear at such wide angle distracting). I use it mostly for fish portraits (and moderate WA), the focal length depends on how shy the creatures are, but I try to go to the minimum possible...

When a wider angle than 20mm is needed, I use fisheye (Canon 8-15mm w/o and with Sony 2x TC; WACP-C/Sony 28-60mm), similar to what Tim was writing...

Wolfgang

Thank you for your input, good to know!

Do you find yourself using the 20-70 much, or do you reach out for your fisheye/WACP more often?

Hey dimi

I use a fisheye for almost everything wide-angle. I had the Signa 15mm for my D800 and loved it. No, I wouldn’t go with the 20-70.

If you want a topside zoom - which is a no-brainer - I’d go with the 28-200. Even better a 24-200 if you can. I got the Nikkor 24-200 topside and love it. It’d be perfect I’d think for topside Galapagos. Useless underwater!

10 minutes ago, TimG said:

Hey dimi

I use a fisheye for almost everything wide-angle. I had the Signa 15mm for my D800 and loved it. No, I wouldn’t go with the 20-70.

If you want a topside zoom - which is a no-brainer - I’d go with the 28-200. Even better a 24-200 if you can. I got the Nikkor 24-200 topside and love it. It’d be perfect I’d think for topside Galapagos. Useless underwater!

Very helpful, thanks! haven't seen a 24-200 for E-mount. Just the 24-240, but that one appears to be much worse than the Tamron optically.

1 hour ago, dimsak said:

Thank you for your input, good to know!

Do you find yourself using the 20-70 much, or do you reach out for your fisheye/WACP more often?

From the range of angles of view (AOV) available, it is no question that I prefer the fisheye/WACP option. As already said, my personal preference is similar to what Tim was writing: Macro +/- SMC-1(3) (Almost for sure I will acquire also the rumored Laowa 180mm AF 1.5x lens as a second macro option, when the UW performance is good) or, alternatively, the fisheye...

The 20-70mm is a nice third option, when there are multiple dives possible, certainly no substitute for the fisheye. It is always good to have different lenses/perspectives for a slide show/image collection. It requires, however, an additional and bigger domeport plus substantial extension (170mm sphere section domeport for 20-70mm vs. 140mm hemisphere for Canon 8-15mm fisheye)...

Amongst the fisheye setups (Canon 8-15mm w/o TC; Canon 8-15mm + 2x Sony TC; WACP-C/28-60mm), I clearly prefer the Canon 8-15mm + 2x Sony TC - it has the most versatile AOV range. I am still not at a final cinclusion regarding IQ, but according to my (very subjective) judgement, Canon 8-15mm + 2x Sony TC has very similar IQ compared to WACP-C/28-60mm (I look mostly at sharpness in the middle of the frame). The pure Canon 8-15mm gives maybe a little bit better IQ, but it can not much, it is maybe possible, but certainly hard to tell, which image was taken with TC and which w/o. Over time this lead me to prefer the Canon 8-15mm + 2x Sony TC setup: Just yesterday I returned from a 9-day diving holiday in Croatia and I always was using the Canon 8-15mm + 2x Sony TC (or, alternatively, the Sony 90mm macro +/- SMC1). The WACP-C remained untouched in the suitcase (and also the 20-70mm, but I rather would have taken the 20-70mm before the WACP-C, because of its excellent sharpness)...

Wolfgang

P.S.: you write that you plan to use the 20-70mm also for topside and you have already the Sigma 15mm (which domeport? can it also be used with the 20-70mm?). Certainly these two lenses are very good for the beginning and after a while you will know what is best for you...

Edited Monday at 12:13 PM1 day by Architeuthis

26 minutes ago, Architeuthis said:

From the range of angles of view (AOV) available, it is no question that I prefer the fisheye/WACP option. As already said, my personal preference is similar to what Tim was writing: Macro +/- SMC-1(3) (Almost for sure I will acquire also the rumored Laowa 180mm AF 1.5x lens as a second macro option, when the UW performance is good) or, alternatively, the fisheye...

The 20-70mm is a nice third option, when there are multiple dives possible, certainly no substitute for the fisheye. It is always good to have different lenses/perspectives for a slide show/image collection. It requires, however, an additional and bigger domeport plus substantial extension (170mm sphere section domeport for 20-70mm vs. 140mm hemisphere for Canon 8-15mm fisheye)...

Amongst the fisheye setups (Canon 8-15mm w/o TC; Canon 8-15mm + 2x Sony TC; WACP-C/28-60mm), I clearly prefer the Canon 8-15mm + 2x Sony TC - it has the most versatile AOV range. I am still not at a final cinclusion regarding IQ, but according to my (very subjective) judgement, Canon 8-15mm + 2x Sony TC has very similar IQ compared to WACP-C/28-60mm (I look mostly at sharpness in the middle of the frame). The pure Canon 8-15mm gives maybe a little bit better IQ, but it can not much, it is maybe possible, but certainly hard to tell, which image was taken with TC and which w/o. Over time this lead me to prefer the Canon 8-15mm + 2x Sony TC setup: Just yesterday I returned from a 9-day diving holiday in Croatia and I always was using the Canon 8-15mm + 2x Sony TC (or, alternatively, the Sony 90mm macro +/- SMC1). The WACP-C remained untouched in the suitcase (and also the 20-70mm, but I rather would have taken the 20-70mm before the WACP-C, because of its excellent sharpness)...

Wolfgang

P.S.: you write that you plan to use the 20-70mm also for topside and you have already the Sigma 15mm (which domeport? can it also be used with the 20-70mm?). Certainly these two lenses are very good for the beginning and after a while you will know what is best for you...

Thank you for the detailed viewpoint!

This thread (and the others i ve looked at) consistently mention that fisheye or macro is usually the best option. I think I will thus skip the 20-70 (at least for now) and go with the 28-200 for topside (which should be a bit better suited for a all-in-one travel lens)

On fish-eye, I was also considering the 8-15 canon too, but went with the 15mm Sigma as a very cheap alternative (got the lens for just 80 USD, and the metabones adapter was 100, but I ll need it for the 8-15 too if I choose to switch).

The main appeal of the Canon with the teleconverter is of course the zoom, which I understand you also find very useful.

On macro, I am thinking the 90mm from Tamron, but I am not sure if the diopters will work nicely, since the lens is a bit shorter than the Sony 90mm (for which the port I have is designed). May I ask what you are using there?

41 minutes ago, Architeuthis said:

you write that you plan to use the 20-70mm also for topside and you have already the Sigma 15mm (which domeport? can it also be used with the 20-70mm?)

I plan to use the Sigma with the 6 inch, and would probably use the 20-70 with the 8 inch. I have some options (in 20mm increments) in terms of port lengths, which I can use with both domes, so I should be able to get a decent fit (a bit wary of the 20-70, as I am not sure it will be shallow enough to avoid vignetting but long enough to support the 70mm end; but I am getting convinced to skip that lens at least for now as mentioned above!)

If you're looking for a bit more "reach" with the fisheye, does the Sigma 15mm work with a Kenko 1.4TC? Hmmmm, not sure but others will have view. I think it does.

That'd be a cheap way of increasing your options. You'd only need the TC and a 20mm extension.

33 minutes ago, TimG said:

If you're looking for a bit more "reach" with the fisheye, does the Sigma 15mm work with a Kenko 1.4TC? Hmmmm, not sure but others will have view. I think it does.

That'd be a cheap way of increasing your options. You'd only need the TC and a 20mm extension.

Good idea, I think it works (I saw Phil mention it does on a different post I believe). The extension I would need is only ~50USD, so it is indeed quite cheap overall.

Downside is that I would need to make my choice before the dive. Will probably hold o that one, but I ll keep it in mind for sure if I find myself wanting more reach!

1 minute ago, dimsak said:

Downside is that I would need to make my choice before the dive. Will probably hold o that one, but I ll keep it in mind for sure if I find myself wanting more reach!

That's always the case no matter how many or what lenses you have. It goes to the heart of what I often bang on about. You have to decide before you dive what you want to photograph and go equipped for that. That, to me, is where it does wrong with a mid-zoom: neither here nor there. It's not just the equipment but the mindset too. Go set up for macro and you hunt for macro subjects and their frames. Fisheye and you're hunting wide-angle, looking for sunballs etc; mid-zoom - errrr, heaven knows - bit of this, bit of that, a lot of nothing......

I am shooting a A7RV in a Seafrogs Housing with the 17-50 Tamron. I designed a zoom ring for it, if you want the file :)

5 hours ago, muude.dk said:

I am shooting a A7RV in a Seafrogs Housing with the 17-50 Tamron. I designed a zoom ring for it, if you want the file :)

Hey there!

Good to hear! Is that your main setup? which dome do you use, and which extension ring?

I d appreciate the file for the zoom gear, yes! A photo or two on either side of the zoom range would also be useful, if you have any readily available!

Thanks!