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Merry Christmas!

I am looking for a bit of advice, and perhaps some reassurance on my imminent setup choices. I am an avid snorkeler in the North of Scotland, in the water probably 300 days of the year. I also scuba dive here weekly. As I snorkel and freedive I have been enjoying using a small camera set up without strobes, olympus OMD EM5MKII in nauticam housing with an 8mm fisheye and mini dome. I really enjoy shooting split shots and like the versatility of the fisheye.

I've wanted to start using strobes for my scuba and now have two inon z330s, but I enjoy using the camera without strobes down to 10m whilst snorkeling as it is less bulky. This is my first underwater camera setup, and when I have come to print images larger, they just aren't as sharp as I'd like. So my research has lead me to look at something with a larger sensor that would be far more light sensitive, whilst not being too bulky. I've settled on a Sony A7Riv with a sigma 15mm fisheye and 14mm dome port.

Does this sound like the correct setup for how I dive or is there something out there that I am overlooking? Any advise would be greatly appreciated.

 

 

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Interesting.  I think the 8mm is super sharp even with large prints.  I would use the Inons to brighten the UW close subjects in your split photos.  With the Sony FF you will have VERY slightly improved sharpness but more bulk as well.

Are you shooting with RAW and applying some appropriate sharpening?  What F aperture are you using?

Edited by nudibranco
missing question

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What do you mean by correct? I'd first look into how you are doing with your current setup - when you say images are not sharp when you print big - how large do you want to print?  Is it sharpness you are concerned about or other issues as well? I use the the panasonic 8mm fisheye and it is very sharp lens.  The EM-5 mkII sensor will give you 39 x 29.2cm prints at 300 dpi natively and should go a bit bigger with some re-sampling work without too much trouble. 

You may run into noise issues in low light  and it can be a touch tricky framing and focusing on subjects for example if you have a scene with close elements and middle distance elements - focusing on the middle distance can cause the really close stuff to fall outside the depth of field - you actually need to focus on the closest element to get the most out of your depth of field - even with a fisheye lens.  What sort of settings are you typically using for your images (shutter speed - aperture - ISO).  Larger sensors can produce nice results for you but also can be more demanding and I'd hate to see you laying all the money down only to find that technique could give you a decent improvement. 

On the choice of Sony - it's one weakness is potentially white balance at depth without lights.

 

 

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Hey guys, many thanks for the speedy replies. When I mention sharpness i do indeed mean noise was the issue (I have the Cannon 8mm).  Most shooting whilst snorkeling is done in the top 5m, but in green water with a vis of 5-10m, on mainly cloudy days. Obviously I like to make the most of days when the sun shines!

I shoot with RAW and adjust in Lightroom, but I'd like to be able to print comfortably above 30x40 inches.

Yes I'm sure that my technique is awful Chris and I do truly welcome your advice! In natural light at 5m I am typically shooting at ISO 320 to 400, f3.2 and 1/100sec. I often have to shoot at ISO 800 at this depth too.  The low natural light obviously has an impact on the usable depth of field so I was hoping to find something that would make the most of this, whilst still keeping the strobes for really low light days/depth.

I dived the Med this year and was able to shoot at 25m, ISO 250 f5.6 1/200s without any issues, but I guess that is the difference that sunshine and 40m vis brings!

 

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Try shooting in a well lit swimming pool, bracing yourself on the bottom or side, shoot at 1/200th and f8, auto ISO and see if you have the same sharpness issues. I think f3.2 and 1/100th will give you crappy shots whatever gear you use.  Also try lighting an underwater subject with flash, say ISO 200, f11 and 1/200th and see if that's sharp. I doubt it's your gear that's a limitation. Let us know!

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2 hours ago, allyclaret said:

Hey guys, many thanks for the speedy replies. When I mention sharpness i do indeed mean noise was the issue (I have the Cannon 8mm).  Most shooting whilst snorkeling is done in the top 5m, but in green water with a vis of 5-10m, on mainly cloudy days. Obviously I like to make the most of days when the sun shines!

I shoot with RAW and adjust in Lightroom, but I'd like to be able to print comfortably above 30x40 inches.

Yes I'm sure that my technique is awful Chris and I do truly welcome your advice! In natural light at 5m I am typically shooting at ISO 320 to 400, f3.2 and 1/100sec. I often have to shoot at ISO 800 at this depth too.  The low natural light obviously has an impact on the usable depth of field so I was hoping to find something that would make the most of this, whilst still keeping the strobes for really low light days/depth.

I dived the Med this year and was able to shoot at 25m, ISO 250 f5.6 1/200s without any issues, but I guess that is the difference that sunshine and 40m vis brings!

 

f:3.2 is too wide open with the fisheye and the dome - try f:8.0 (at most 7.6) and increase ISO not to go slower than 1/60 s. Improve noise with LR. If this is not sufficient, the larger sensor may help. At the current situation (f:3.2) it is certainly NOT the camera that makes the image unsharp...

 

Wolfgang

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agree f3.2 is a bit limiting, getting everything in focus at that aperture and the aberrations from the lens itself and the dome - I see you call it a mini dome - the Zen 100mm dome? I would suggest lowering your shutter speed a little for a start, the IS in the body is very good, you will have issues with moving subjects of course, but 1/50 - 1/60 should help a little maybe 1/50 @ f4.5 ISO400 or 1/50 @ f5.6  ISO640?

I would think you could go to f5.6 probably still at the cost of corner sharpness perhaps, but better than f3.2. The full frame sensor will certainly be gathering more light but it is also more demanding , you need to go f6.3 at least to get the same depth of field as the current lens, preferably f11. So if you went f11 on the Sony, that's 3 2/3 stops over the current setting of f3.2 and assuming you do that all in ISO that's ISO5000.    So the summary if I've done counting of stops correctly 1/100 f3.2 ISO400 = 1/100 f11 ISO5000.  While full frame will still look better than the m43 system as you've gathered 4x the light  - will it be $$$ better?

If you are technically minded then this DXO mark page allows you to compare the sensors.  if you looks at the measurements ISO400 on EM-5 mkII is about equal to ISO 1600 on the SONY for Signal to noise and dynamic range:  https://www.dxomark.com/Cameras/Compare/Side-by-side/Olympus-OM-D-E-M5-Mark-II-versus-Olympus-OM-D-E-M1-Mark-II-versus-Sony-A7R-IV___1006_1136_1326

I also noted you are using the Canon lens (8-15 fisheye?) at f3.2 ?  I'm assuming this is with the speedbooster ?  The speedbooster might be good but you're adding the aberration from the booster to the abberation from the lens near wide open to the issues with a small dome shot at wide aperture and pasting noise over the top of it all.  It doesn't seem ideal to me.

An alternative you might consider is the WWL-1 it's specialty is shooting at wider apertures - it allows use of the either the 14-42 lenses or the 14mm f2.5 pancake lens and gives you a 130° field not quite fisheye but the fisheye angle of view mostly is in the extreme corners the horizontal field of view with an 8mm  fisheye is about 130° while the WWL will be about 115°.  I would think you could shoot that combo at f4 or maybe stopped down just a little more  and just touch up the ISO a little - maybe 1/60 f4 ISO400?   You can upgrade the WWL-1 to Sony full frame (or other options??) at a later date, there's been some posts on that here recently.

Having said all of that 30 x 40 inches is a stretch for any m43 sensor - it can be done but you are pushing things - the 20 MP EM1 mkII is 5188 x 3888 pixels and at 30" x 40" is 129 dpi - you can resample within reason but the starting material needs to be very good and the file carefully prepared to get the most out of it - just dropping the file into the print shop almost certainly is not giving you the best that can be obtained from the file.  If you are using 30x40 paper then a 1.5" border all round is 36x27 and 144 dpi which is geeting into printable territory natively.  other tricks include selective sharpening on main subject only and selective background noise reduction as well as careful sharpening techniques to avoid enhancing noise.  This is the definitive sharpening guide IMO https://manualzz.com/doc/17987997/image-sharpening-make-it-really-sharp-jeff-schewe  It's old but still perfectly valid and can be done with standard PS.

All this is centered around natural light - with strobes just turn up the power and shoot at f8-11 and keep the ISO down.

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I think the image softness is an aperture/dome port related issue, rather than a lens one. Shooting at f/3.2 will produce soft corners.

I am happy shooting underwater at much slower shutter speeds than others have suggested. The crucial ingredient is getting your camera set up completely neutrally buoyant. I regularly shoot at 1/10, and on occasion slower. But, this does require a super stable platform that may be difficult to achieve while snorkelling.

As others have suggested, I would aim to keep aperture at f/5.6 or, even better, f/8. Use the combination of slower shutter speeds (when possible) and ISO to get your exposure. 

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Thank you all so very much for taking the time out to reply and for your patience!  

@ChrisRoss, it's an Olympus 8mm not Canon that I currently have, apologies for this.  

I have been reluctant to increase the ISO over 800 due to noise, but today I listened to you all and the results were much better (of course!!!). Thank you all so much. I was shooting around 3-5m depth at f6.3 ISO 1600 1/50 and the noise wasn't that much different to at ISO 800.  That sharpening guide is excellent @ChrisRoss, thank you.

As you mention @adamhanlon it's hard to stay still at depth for long when snorkeling so I found 1/50 about the slowest speed, but next time I'll hike up the ISO again and see how I get on.

Still looking to be able to print big so will likely opt for the A7R iv, but now looking at the WWL-1 option with the 28-60mm Sony lens as I have seen talked about on here to give me a wider range of lens options and I'll keep the Olympus with the fisheye for now. Thank you for the for the Water Contacts review video!

 

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