EM-5 and 9-18mm soft images

[waterboy 1]

Hi All,

 

I have recently bought the EM-5 and the Nauticam housing. I love the combo (I was using the G-12 for U/W before and the 5D Mk2 for land).

I shoot mainly natural light and always while FreeDiving.

I have bought the 9-18mm lens and the Nauticam 4inch port for it as a long awaited upgrade.

I have spent a month in Tonga and during that month shot hundreds of Whale and Freediving photos - all of them were not usable due to being super soft and not contrasty.

 

Most were shot on F5.6 on base ISO @1/160 and above.

 

After about two weeks I was told by Nauticam to use F8 and above but I know that past F5.6 on M43 you get diffraction and loose IQ... I tried anyway and the results were not much better. Corners were a bit better but center sharpness was not great any-more.

 

After the trip I have contacted the shop that sold me the lens and have received a new one.

This new lens seems much better but still - images are not really sharp or contrasty. DOF seems very shallow and only a tiny portion of the frame is actually in focus.

I shoot RAW (on the G12 as well) and the images actually look much better ooc from the G12 with a cheap Airdome...

 

I also tried shooting with a strobe and although it is slightly better - its not good (not for a 4K setup).

Anything that is not 100% in the middle of the frame is not sharp.

Zooming to 11mm results in slightly better sharpness but defeats the point of having a wide angle lens.

 

I am happy to post high Rez versions but just to show the general idea - the closer shot was on 9mm with the whale around 3m away in clear water.

 

What am I doing wrong?

I was Told to use a larger dome (to get better edge sharpness), told to buy a fisheye, told to buy the 7-14mm.....

 

As most of my work involves shooting Freedivers I wanted the zoom lens to allow a bit of flexibility..

I have seen some amazing shots with the EM-5. I love the camera but am very frustrated at the moment..

 

Thank you very much,

Erez

[Deep6 7]

I have bought the 9-18mm lens and the Nauticam 4inch port for it as a long awaited upgrade.

I have spent a month in Tonga and during that month shot hundreds of Whale and Freediving photos - all of them were not usable due to being super soft and not contrasty.

 

Most were shot on F5.6 on base ISO @1/160 and above.

 

 

What is the camera distance to subject in your examples?

 

Bob

[JackConnick 76]

These look quite underexposed to me and pretty far away. A higher ISO may help. You may want to consider shooting with a red filter inside the port and doing manual white balance.

 

Jack

[coroander 16]

The first image appears to be out of focus. The second image just appears to be suffering from low contrast and shooting through so much water. I can't comment specifically about the 9-18mm in it's 4" dome.

 

If you're not using Lightroom 4.1, download it (its free for 30 days), open up the second RAW image, increase the Exposure so the whites are brighter (but not near being blown out), increase the Contrast just a bit to about +10, set Clarity to about +30 (just an initial guess), push the Blacks down until contrast is improved (try -45, but whatever looks right), push Whites up as well (maybe as high as +40), go back to Clarity and look for a more optimal position (maybe closer to +50 given the distance of water being shot through), adjust Whites and Blacks again if needed. Now play with Highlights and Shadows and see if the image can be further improved (perhaps around Shadows -30, Highlights +10). Click on Remove Chromatic Aberration.

 

I really like Clarity -- it improves the local contrast that shooting through water destroys -- don't really use it for above water photos or macro much, but it's great for WA shots underwater.

 

You might want to adjust white balance a bit -- increase the Temp a few thousand degrees and then increase the Tint until the water looks nicely blue (and the white bits haven't started turning pink).

Edited December 12, 2012 by coroander

[waterboy 1]

Thanks for the replies.

I shot most of the whales from around 4-6m.

Some shots were from a bit further - up to 12m away for the ones with a few whales.

 

I use Aperture to edit my work and the thing that surprised me most was the difference between the files from the E-M5 and the G-12 out of the camera - the G12 looked much sharper and with more contrast.

When I edited the shots I had to add a lot of contrast and definition (I think its the parallel to clarity with LR).

 

The only way for me to add a filter will be to add it to the front of the lens, but as i mainly shoot whales from the surface I didnt think I really needed that.. guess I was wrong.I played with the white balance in editing and it does help - but produces noise.

 

When I increase exposure I get lots of noise in those images.. Next time I will shoot overexposed and then darken the images. Will shooting brighter with high ISO produce less noise when darkening in post?

 

My other question was about F-stop. Should I shoot on F8-11 (and increase ISO) or stay around F5.6?

 

Will getting a larger port (like the 7-14 6inch) help with corner sharpness more than increasing F-stop? I was surprised by the shallow DOF (a Freedivers head is in focus but his shoulders are already blurred).

so many questions, so much to learn..

Thanks

[tdtaylor 1]

I haven't used my 9-18 UW, but on land it is very sharp. Not quite as sharp as the 7-14, but very respectable. Do you get the same results on land. Might be worth a try to make sure the camera and lens are working well. If it works well, then it is an UW issue.

[coroander 16]

I've been using Aperture since it came out and have a huge collection of photos in it, so it would be a huge advantage to continue using it. However, since i've been using the E-M5, i've abandoned using Aperture in favour of Lightroom 4. Lightroom is just so much better, that even though i prefer Aperture's UI and integration with the Apple universe, i'm using Lightroom because the image quality obtained can be so much better. You simply will not understand how good a camera the E-M5 is until you use Lightroom.

 

Lightroom's noise reduction is also better than Aperture's, and combined with the E-M5's fine grained noise and lack of chroma clumping, you'll get fantastic, detailed images even at high ISO and even when you've had to push the images in post. Generally, i only use NR Luminance correction with the E-M5 and only push NR Detail up a bit when using NR Luminance > 20.

 

The best ISO to use is the one that allows you to achieve the correct exposure, underexposing and pushing in post is less optimal than using a higher ISO and not adjusting the exposure in post. However, you don't want to burn out the brighter areas of the image. The Shadows & Highlight clipping indicators in the EVF are very useful for getting the best exposure.

Edited December 13, 2012 by coroander

[waterboy 1]

Thanks,

I will download LR and give it a shot...

 

No one seems to answer my question about F stops...

 

Cheers,

Erez

[coroander 16]

On diffraction, see:

http://wetpixel.com/forums/index.php?showtopic=25360

[Nicool 26]

Hi Waterboy,

 

As a freediver, I imagine you move a lot underwater, especially with whales around.

Would it be better if you increased a bit the shutter speed? I'm thinking that 1/200th might not be enough.

cheers

Nicolas

[Deep6 7]

Thanks,

I will download LR and give it a shot...

 

No one seems to answer my question about F stops...

 

Cheers,

Erez

 

I don’t own this lens, but here is a quote from dpreview:

 

Central sharpness is generally very high, but the extreme corners are somewhat soft in comparison. Optimum results are generally obtained about a stop down from wide open - around F5.6 at 9mm, and F8 at 18mm. Diffraction starts to have a serious negative impact at F16, with F22 on the whole best avoided.

 

 

Here’s my two cents:

Water has a MAJOR diffusing impact on the image quality. Even in very clear water do not expect image sharpness beyond 1 meter. Darker water exposure tends to hide some of this in the background.

 

“If your pictures aren’t good enough, you aren’t close enough.” – Robert Capa

 

OK, I am spoofing you a little with the Capa quote.

 

Bob

[waterboy 1]

Nicolas, My issue was that i wanted to keep the speed at around 160-250 in order not to have to boost ISO. Now that i realise I can increase iso i will try with faster speeds. Saying that, we had a guy on the group with the 5D MK3 with the 17mmL and he was using F4.5 and 1/100 and he got good results... This is what frustrate me... Being a m43 setup I thought i will have greater DOF @F5.6 that he would have on a FF@F4.5.

 

Bob,

the issue with the whales is that you cant really get too close unless they let you... and when they do - they might suddenly be so close that they will will not fit in the frame even at 9mm. humpbacks are 12m long so there will be at least part of the shot that has more than 1 meter away...

I will try and experiment with different apertures and iso next time i am in the water.

I am now positive that my first lens was a lemon - looking at some test shots i took with it and with the replacement I clearly see a major difference in sharpness.

 

would the Panasonic 8mm fisheye be supirior to the 9-18mm in terms of performance? Has anyone tried the Samyang 7.5mm? Will the fact the samyang is full manual be a major limiting factor here?

 

Thanks,

Erez

[coroander 16]

Erez,

I haven't seen much formal testing of m43 lenses and ports underwater. I'm also curious as to which UWA performs best underwater: the 8mm FE, the 7-14mm or the 9-18mm. One solution would simply be to do the tests ourselves.

 

We can't draw many conclusions about underwater use from above water tests for several reasons:

1) behind a dome, a virtual image is formed underwater, and it's the virtual image we are focusing on. This virtual image is close focus, far closer than lenses are normally tested at, and it's difficult to draw conclusions about lens performance at mid distance or infinity when we want to know about close focus performance; ( http://wetpixel.com/...ll/dome-theory/ )

2) behind a dome, the virtual image is curved and so one needs to use small apertures so that both the centre and edges (which are much closer to the sensor plane) are in focus. Larger domes have the advantage that they move the virtual image further away from the sensor, which increases the depth of field, making it easier to have the corners and centre of the virtual image in focus;

3) the forward and backward location of the lens in the port will alter the relative distances of the centre and corners of the virtual image (and the angle to the dome surface at which the light rays enter);

4) particularly with flat ports, the refraction that occurs between the water/air interface creates chromatic aberration (and spherical aberration?) that increases with the angle of view; and

5) the water itself seriously reduces resolution and the lower the vis the shorter distance over which this occurs.

 

There's a pinned thread here that discusses lens testing:

http://wetpixel.com/...showtopic=35605

 

My preference would be to use the chart below and run a line of these charts along a flat wall of a pool, printed on A4 and laminated, from the centre of the field of view to one of the corners -- maybe 6 charts from centre to corner, placing the corner of the viewfinder exactly in the centre of the last chart and focusing on the centre one with the camera directly in front of point of focus and perpendicular to the wall at 1m from the wall. Repeat the test for a range of apertures from wide open to f/22, and at 3 focal lengths for the zooms...

http://www.panavisio...Siemen_Star.pdf

 

I could test the 8mm FE in this way, although the last chart may have to be placed differently to deal with the 180 degree FOV.

Edited December 16, 2012 by coroander

[Deep6 7]

Nicolas, My issue was that i wanted to keep the speed at around 160-250 in order not to have to boost ISO. Now that i realise I can increase iso i will try with faster speeds. Saying that, we had a guy on the group with the 5D MK3 with the 17mmL and he was using F4.5 and 1/100 and he got good results... This is what frustrate me... Being a m43 setup I thought i will have greater DOF @F5.6 that he would have on a FF@F4.5.

 

Bob,

the issue with the whales is that you cant really get too close unless they let you... and when they do - they might suddenly be so close that they will will not fit in the frame even at 9mm. humpbacks are 12m long so there will be at least part of the shot that has more than 1 meter away...

I will try and experiment with different apertures and iso next time i am in the water.

I am now positive that my first lens was a lemon - looking at some test shots i took with it and with the replacement I clearly see a major difference in sharpness.

 

would the Panasonic 8mm fisheye be supirior to the 9-18mm in terms of performance? Has anyone tried the Samyang 7.5mm? Will the fact the samyang is full manual be a major limiting factor here?

 

Thanks,

Erez

 

Hi Erez,

 

You are right of course about approching whales. What I was trying to point out is the sharpness of your image will always suffer from the subject to the lens distance in water. I don't have the 8 mm, but reviews tend to rate it above the 9-18. It is a 180 deg. FE vs. 100 deg. (@ 9 mm). You may or may not like the fish eye affect on your subjects.

 

I don't know how your images are to be viewed (size of print, web, ....). You should get acceptable results post processing raw data at ISO 400, 800, ...?

 

Bob

[coroander 16]

Actually, i wonder if the first image is out of focus because the whale was too close? I see the minimum focus distance of the 9-18mm is 0.25m. I'm not sure what the optical radius of the 4" dome is, but it's easy to check focus distances. Open up the 2nd image in Aperture (which appears in focus and is for all practical purposes at infinity) and click on the Info tab, then select EXIF Info. You'll find the focus distance there. If the second shot was focused close to 0.25m, then you'll struggle to get in-focus shots at near distances without using a diopter (or stopping down further). Everything behind dome ports underwater is focused between the distance from the sensor to the front of the dome (for objects touching the dome), to the distance you'll find in the EXIF Info for an image which is a focused on an object a considerable distance from the port.

Edited December 16, 2012 by coroander

[coroander 16]

The last thing is where was the focus point, and did the camera achieve focus? I always select a single autofocus point and generally always use the small Magnify focus point ( http://wetpixel.com/forums/index.php?showtopic=48625 ). I focus on some area with high contrast, since the OM-D's contrast detect autofocus doesn't work in areas of the scene with low contrast. If the camera is set to use any autofocus point, then it will find someplace with some good contrast (like the water at the surface) and focus there.

 

In Aperture there's a "Show / Hide Focus Points on Viewer" icon in the upper right of the Info tab; very useful for investigating focus issues...

[waterboy 1]

Had a look at the focus points and the focus distance - Focus was good and focus distance was .45 so within the workable focus range.

The more I look at the photos the more I can see how soft and faulty was my old lens.

I have one set of images that I shot at 11mm and on F11 and they are by far the best ones (even though they needed cropping and lots of work). I know the WB is not the best..

I have downloaded LR4 and can't seem to notice a huge difference in processing over Aperture..

I will have to jump into the pool and conduct some tests...

 

I am getting really tempted to get the 12-50mm after seeing Alex's last few shots. Either this lens or the 60mm...

 

cheers,

Erez

[chris_l 6]

I assume you have the 14-42 lens also.

Have you tried it?

my 9-18 is definitely sharper than my kit 14-42, so you probably did have a bad lens.

[waterboy 1]

I actually only have this one lens so I couldn't test any other option until I returned from tonga and swapped lenses.

 

[deepbluemd 9]

If you're not using Lightroom 4.1, download it (its free for 30 days), open up the second RAW image, increase the Exposure so the whites are brighter (but not near being blown out), increase the Contrast just a bit to about +10, set Clarity to about +30 (just an initial guess), push the Blacks down until contrast is improved (try -45, but whatever looks right), push Whites up as well (maybe as high as +40), go back to Clarity and look for a more optimal position (maybe closer to +50 given the distance of water being shot through), adjust Whites and Blacks again if needed. Now play with Highlights and Shadows and see if the image can be further improved (perhaps around Shadows -30, Highlights +10). Click on Remove Chromatic Aberration.

 

I really like Clarity -- it improves the local contrast that shooting through water destroys -- don't really use it for above water photos or macro much, but it's great for WA shots underwater.

 

You might want to adjust white balance a bit -- increase the Temp a few thousand degrees and then increase the Tint until the water looks nicely blue (and the white bits haven't started turning pink).

 

I wanted to echo Coroander's suggestion to try Lightroom 4. I've been a long time Aperture user, and have been pleased with the ease of workflow and organization, and until now, happy with the image quality. I was intrigued when Coroander stated that LR4 is really yields a tangible difference in image quality. I decided to download the free trial, and what can I say, I'm hooked. While the LR4 workflow requires a greater upfront time investment to understand, the dividends are huge. I'm impressed with this program on so many levels, and as I get increasingly comfortable with the workflow, (developing, rating, and placing images in collections) the array of preset adjustments and image tools is convincing me that Aperture will no longer suffice. Even simple one click presets seem to do a better job of improving image quality, and the results are often right on the money, without need for excessive tweaking, trial and error. After deciding to try it, I asked a fellow photographer about LR4 learning aids and he recommended Scott Kelby's Adobe Photoshop Lightroom 4 for Digital Photographers. I've read most of it now and he offers great advice for setting up a workflow process, which is very important if you are coming from an application like Aperture, and a million tips and examples on how to get the most out of your images. In every chapter, kelby gives shortcut commands and how they can simplify and speedup the work of importing, editing and storing images. I know this app will keep me learning for some time to come, but I'll happily put in the effort to keep improving. Here's one non UW example, as I've only loaded about 50 topside pictures into it so far and haven't been underwater since I got the program. This was a complete crap, poor color, image that I decided to experiment on while learning LR4. One click with a B&W preset and this image was the result. I'm at work so I pulled this image from an email I sent to my wife otherwise I'd post the original along with it. Still not going to win any awards, but if you'd seen the original you'd be smiling like me.

Anyway, like the commercial for life cereal used to say...try it, you'll like it.

 

Edited December 20, 2012 by deepbluemd